Barriers and facilitators to use of compression therapy by people with venous leg ulcers: A qualitative exploration.

AIMS: To explore barriers to, and facilitators of, adherence to compression therapy, from the perspective of people with venous leg ulcers. DESIGN: An interpretive, qualitative, descriptive study involving interviews with patients. METHODS: Participants were purposively sampled from respondents to a survey exploring attitudes to compression therapy in people with venous leg ulcers. Sampling continued until data saturation: 25 interviews between December 2019 and July 2020. Inductive thematic analysis of interview transcripts was undertaken to create a framework for the data, followed by deductive analysis informed by the Common-Sense Model of Self-Regulation. RESULTS: A range of knowledge and understanding about the cause of venous leg ulcers and the mechanisms of compression therapy was demonstrated, which was not particularly related to adherence. Participants talked about their experience with different compression methods and their concerns about the length of time healing could take. They also spoke about aspects of the organization of services which affected their care. CONCLUSION: Identifying specific, individual barriers/facilitators to compression therapy is not simple, rather factors combine to make adherence more or less likely or possible. There was no clear relationship between an understanding of the cause of VLUs or the mechanism of compression therapy and adherence; different compression therapies presented different challenges for patients; unintentional non-adherence was frequently mentioned; and the organization of services could impact on adherence. Ways in which people could be supported to adhere to compression therapy are indicated. Implications for practice include issues relating to communication with patients; taking into account patients' lifestyles and ensuring that they know about useful 'aids'; providing services that are accessible and provide continuity of appropriately trained staff; minimizing unintentional non-adherence; and acknowledging that healthcare professionals will always need to support/advise those who cannot tolerate compression. IMPACT: Compression therapy is a cost-effective, evidence-based treatment for venous leg ulcers. However, there is evidence that patients do not always adhere to this therapy and there is limited research investigating reasons why patients do not wear compression. The study found no clear relationship between an understanding of the cause of VLUs or the mechanism of compression therapy and adherence; that different compression therapies presented different challenges for patients; that unintentional non-adherence was frequently mentioned and that the organization of services could impact on adherence. Attending to these findings offers the opportunity to increase the proportion of people undergoing appropriate compression therapy and achieving complete wound healing, the main outcome desired by this group. PATIENT/PUBLIC CONTRIBUTION: A patient representative sits on the Study Steering Group, contributing to the work from developing the study protocol and interview schedule to interpretation and discussion of findings. Members of a Wounds Research Patient and Public Involvement Forum were consulted about interview questions.

Pressure redistributing static chairs for preventing pressure ulcers.

BACKGROUND: Sitting can be viewed as a therapeutic intervention and an important part of a person's recovery process; but the risk of ulceration must be mitigated. Interventions for ulcer prevention in those at risk from prolonged sitting include the use of specialist cushions and surfaces, especially for wheelchair users. Whilst there is interest in the effects of different pressure redistributing cushions for wheelchairs, the benefits of pressure redistributing static chairs, compared with standard chairs, for pressure ulcer development in at-risk people are not clear. OBJECTIVES: To assess the effects of pressure redistributing static chairs on the prevention of pressure ulcers in health, rehabilitation and social care settings, and places of residence in which people may spend their day. SEARCH METHODS: In June 2021 we searched the following electronic databases to identify reports of relevant randomised clinical trials: the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid Embase and EBSCO CINAHL Plus (Cumulative Index to Nursing and Allied Health Literature). We also searched clinical trials registers for ongoing and unpublished studies, and reference lists of relevant systematic reviews, meta-analyses and health technology reports. There were no restrictions by language, date of publication or study setting. SELECTION CRITERIA: We sought to include published or unpublished randomised controlled trials that assessed pressure redistributing static chairs in the prevention or management of pressure ulcers. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection. We planned that two review authors would also assess the risk of bias, extract study data and assess the certainty of evidence according to GRADE methodology. MAIN RESULTS: We did not identify any studies that met the review eligibility criteria, nor any registered studies investigating the role of pressure redistributing static chairs in the prevention or management of pressure ulcers. AUTHORS' CONCLUSIONS: Currently, there is no randomised evidence that supports or refutes the role of pressure redistributing static chairs in the prevention or management of pressure ulcers. This is a priority area and there is a need to explore this intervention with rigorous and robust research.

Reconstructive surgery for treating pressure ulcers.

BACKGROUND: There are several possible interventions for managing pressure ulcers (sometimes referred to as pressure injuries), ranging from pressure-relieving measures, such as repositioning, to reconstructive surgery. The surgical approach is usually reserved for recalcitrant wounds (where the healing process has stalled, or the wound is not responding to treatment) or wounds with full-thickness skin loss and exposure of deeper structures such as muscle fascia or bone. Reconstructive surgery commonly involves wound debridement followed by filling the wound with new tissue. Whilst this is an accepted means of ulcer management, the benefits and harms of different surgical approaches, compared with each other or with non-surgical treatments, are unclear. This is an update of a Cochrane Review published in 2016. OBJECTIVES: To assess the effects of different types of reconstructive surgery for treating pressure ulcers (category/stage II or above), compared with no surgery or alternative reconstructive surgical approaches, in any care setting. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was January 2022. SELECTION CRITERIA: Published or unpublished randomised controlled trials (RCTs) that assessed reconstructive surgery in the treatment of pressure ulcers. DATA COLLECTION AND ANALYSIS: Two review authors independently selected the studies, extracted study data, assessed the risk of bias and undertook GRADE assessments. We would have involved a third review author in case of disagreement. MAIN RESULTS: We identified one RCT conducted in a hospital setting in the USA. It enrolled 20 participants aged between 20 and 70 years with stage IV ischial or sacral pressure ulcers (involving full-thickness skin and tissue loss). The study compared two reconstructive techniques for stage IV pressure ulcers: conventional flap surgery and cone of pressure flap surgery, in which a large portion of the flap tip is de-epithelialised and deeply inset to obliterate dead space. There were no clear data for any of our outcomes, although we extracted some information on complete wound healing, wound dehiscence, pressure ulcer recurrence and wound infection. We graded the evidence for these outcomes as very low-certainty. The study provided no data for any other outcomes. AUTHORS' CONCLUSIONS: Currently there is very little randomised evidence on the role of reconstructive surgery in pressure ulcer management, although it is considered a priority area. More rigorous and robust research is needed to explore this intervention.

Negative pressure wound therapy for surgical wounds healing by primary closure.

BACKGROUND: Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). Existing evidence for the effectiveness of NPWT on postoperative wounds healing by primary closure remains uncertain. OBJECTIVES: To assess the effects of NPWT for preventing SSI in wounds healing through primary closure, and to assess the cost-effectiveness of NPWT in wounds healing through primary closure. SEARCH METHODS: In January 2021, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries and references of included studies, systematic reviews and health technology reports. There were no restrictions on language, publication date or study setting. SELECTION CRITERIA: We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, assessment using the Cochrane risk of bias tool, and quality assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. Our primary outcomes were SSI, mortality, and wound dehiscence. MAIN RESULTS: In this fourth update, we added 18 new randomised controlled trials (RCTs) and one new economic study, resulting in a total of 62 RCTs (13,340 included participants) and six economic studies. Studies evaluated NPWT in a wide range of surgeries, including orthopaedic, obstetric, vascular and general procedures. All studies compared NPWT with standard dressings. Most studies had unclear or high risk of bias for at least one key domain. Primary outcomes Eleven studies (6384 participants) which reported mortality were pooled. There is low-certainty evidence showing there may be a reduced risk of death after surgery for people treated with NPWT (0.84%) compared with standard dressings (1.17%) but there is uncertainty around this as confidence intervals include risk of benefits and harm; risk ratio (RR) 0.78 (95% CI 0.47 to 1.30; I2 = 0%). Fifty-four studies reported SSI; 44 studies (11,403 participants) were pooled. There is moderate-certainty evidence that NPWT probably results in fewer SSIs (8.7% of participants) than treatment with standard dressings (11.75%) after surgery; RR 0.73 (95% CI 0.63 to 0.85; I2 = 29%). Thirty studies reported wound dehiscence; 23 studies (8724 participants) were pooled. There is moderate-certainty evidence that there is probably little or no difference in dehiscence between people treated with NPWT (6.62%) and those treated with standard dressing (6.97%), although there is imprecision around the estimate that includes risk of benefit and harms; RR 0.97 (95% CI 0.82 to 1.16; I2 = 4%). Evidence was downgraded for imprecision, risk of bias, or a combination of these. Secondary outcomes There is low-certainty evidence for the outcomes of reoperation and seroma; in each case, confidence intervals included both benefit and harm. There may be a reduced risk of reoperation favouring the standard dressing arm, but this was imprecise: RR 1.13 (95% CI 0.91 to 1.41; I2 = 2%; 18 trials; 6272 participants). There may be a reduced risk of seroma for people treated with NPWT but this is imprecise: the RR was 0.82 (95% CI 0.65 to 1.05; I2 = 0%; 15 trials; 5436 participants). For skin blisters, there is low-certainty evidence that people treated with NPWT may be more likely to develop skin blisters compared with those treated with standard dressing (RR 3.55; 95% CI 1.43 to 8.77; I2 = 74%; 11 trials; 5015 participants). The effect of NPWT on haematoma is uncertain (RR 0.79; 95 % CI 0.48 to 1.30; I2 = 0%; 17 trials; 5909 participants; very low-certainty evidence). There is low-certainty evidence of little to no difference in reported pain between groups. Pain was measured in different ways and most studies could not be pooled; this GRADE assessment is based on all fourteen trials reporting pain; the pooled RR for the proportion of participants who experienced pain was 1.52 (95% CI 0.20, 11.31; I2 = 34%; two studies; 632 participants). Cost-effectiveness Six economic studies, based wholly or partially on trials in our review, assessed the cost-effectiveness of NPWT compared with standard care. They considered NPWT in five indications: caesarean sections in obese women; surgery for lower limb fracture; knee/hip arthroplasty; coronary artery bypass grafts; and vascular surgery with inguinal incisions. They calculated quality-adjusted life-years or an equivalent, and produced estimates of the treatments' relative cost-effectiveness. The reporting quality was good but the evidence certainty varied from moderate to very low. There is moderate-certainty evidence that NPWT in surgery for lower limb fracture was not cost-effective at any threshold of willingness-to-pay and that NPWT is probably cost-effective in obese women undergoing caesarean section. Other studies found low or very low-certainty evidence indicating that NPWT may be cost-effective for the indications assessed. AUTHORS' CONCLUSIONS: People with primary closure of their surgical wound and treated prophylactically with NPWT following surgery probably experience fewer SSIs  than people treated with standard dressings but there is probably no difference in wound dehiscence (moderate-certainty evidence). There may be a reduced risk of death after surgery for people treated with NPWT compared with standard dressings but there is uncertainty around this as confidence intervals include risk of benefit and harm (low-certainty evidence). People treated with NPWT may experience more instances of skin blistering compared with standard dressing treatment (low-certainty evidence). There are no clear differences in other secondary outcomes where most evidence is low or very low-certainty. Assessments of cost-effectiveness of NPWT produced differing results in different indications. There is a large number of ongoing studies, the results of which may change the findings of this review. Decisions about use of NPWT should take into account surgical indication and setting and consider evidence for all outcomes.

Evidence assessing the development, evaluation and implementation of digital health technologies in wound care: A rapid scoping review.

OBJECTIVE: To scope published data on the development, evaluation and implementation of digital health technologies for use in wound care. We focused on digital health technologies that supported one or more of the following functions: system level (such as electronic health records, management systems), wound imaging and measurement, and communication. METHODS: For this rapid scoping review, Ovid MEDLINE and Ovid Embase were searched in January 2021 and relevant experts were consulted. We identified English language publications that reported the development, evaluation, and/or implementation of relevant digital health technologies. Studies were screened and data extracted and coded following the established scoping review methodology. Data were presented narratively, and in tabular formats. RESULTS: We included 156 studies in the review. After reported technologies were categorised based on their predominant function, 51 (32.7%) studies reported on system level technologies; 123 (78.8%) on wound imaging and measurement technologies; and 34 (21.8%) on communication-focused technologies such as video-conferencing technologies, messaging technologies). Of the 156 studies, 37 (23.7%) reported data on development of the technology; 135 (86.5%) reported evaluation activities, mainly for wound imaging and measurement technologies; and 2 (1.3%) reported implementation research. CONCLUSION: There is increasing focus on digital health technologies in wound care. Assessment of digital health technologies aimed at wound care has mainly been for those with a primary function around wound imaging and measurement. Most studies reported evaluation whilst evidence suggests the field may lack transparent reporting of technology development and implementation activities that could aid further decision-making.

Bacteria and bioburden and healing in complex wounds: A prognostic systematic review.

The wound microbiome may play an important role in the wound healing process. We conducted the first systematic prognosis review investigating whether aspects of the wound microbiome are independent prognostic factors for the healing of complex wounds. We searched Medline, Embase, CINAHL and the Cochrane Library to February 2019. We included longitudinal studies which assessed the independent association of aspects of wound microbiome with healing of complex wounds while controlling for confounding factors. Two reviewers extracted data and assessed risk of bias and certainty of evidence using the GRADE approach. We synthesised studies narratively due to the clinical and methodological heterogeneity of included studies and sparse data. We identified 28 cohorts from 21 studies with a total of 38,604 participants, including people with diabetes and foot ulcers, open surgical wounds, venous leg ulcers and pressure ulcers. Risk of bias varied from low (2 cohorts) to high (17 cohorts); the great majority of participants were in cohorts at high risk of bias. Most evidence related to the association of baseline clinical wound infection with healing. Clinical infection at baseline may be associated with less likelihood of wound healing in foot ulcers in diabetes (HR from cohort with moderate risk of bias 0.53, 95% CI 0.33 to 0.83) or slower healing in open surgical wounds (HR 0.65, 95% CI 0.51 to 0.83); evidence in other wounds is more limited. Most other associations assessed showed no clear relationship with wound healing; evidence was limited and often sparse; and we documented gaps in the evidence. There is low certainty evidence that a diagnosis of wound infection may be prognostic of poorer healing in foot ulcers in diabetes, and some moderate certainty evidence for this in open surgical wounds. Low certainty evidence means that more research could change these findings.

Compression bandages or stockings versus no compression for treating venous leg ulcers.

BACKGROUND: Leg ulcers are open skin wounds on the lower leg that can last weeks, months or even years. Most leg ulcers are the result of venous diseases. First-line treatment options often include the use of compression bandages or stockings. OBJECTIVES: To assess the effects of using compression bandages or stockings, compared with no compression, on the healing of venous leg ulcers in any setting and population. SEARCH METHODS: In June 2020 we searched the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE (including In-Process & Other Non-Indexed Citations), Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions by language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that compared any types of compression bandages or stockings with no compression in participants with venous leg ulcers in any setting. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, and risk-of-bias assessment using the Cochrane risk-of-bias tool. We assessed the certainty of the evidence according to GRADE methodology. MAIN RESULTS: We included 14 studies (1391 participants) in the review. Most studies were small (median study sample size: 51 participants). Participants were recruited from acute-care settings, outpatient settings and community settings, and a large proportion (65.9%; 917/1391) of participants had a confirmed history or clinical evidence of chronic venous disease, a confirmed cause of chronic venous insufficiency, or an ankle pressure/brachial pressure ratio of greater than 0.8 or 0.9. The average age of participants ranged from 58.0 to 76.5 years (median: 70.1 years). The average duration of their leg ulcers ranged from 9.0 weeks to 31.6 months (median: 22.0 months), and a large proportion of participants (64.8%; 901/1391) had ulcers with an area between 5 and 20 cm2. Studies had a median follow-up of 12 weeks. Compression bandages or stockings applied included short-stretch bandage, four-layer compression bandage, and Unna's boot (a type of inelastic gauze bandage impregnated with zinc oxide), and comparator groups used included 'usual care', pharmacological treatment, a variety of dressings, and a variety of treatments where some participants received compression (but it was not the norm). Of the 14 included studies, 10 (71.4%) presented findings which we consider to be at high overall risk of bias. Primary outcomes There is moderate-certainty evidence (downgraded once for risk of bias) (1) that there is probably a shorter time to complete healing of venous leg ulcers in people wearing compression bandages or stockings compared with those not wearing compression (pooled hazard ratio for time-to-complete healing 2.17, 95% confidence interval (CI) 1.52 to 3.10; I2 = 59%; 5 studies, 733 participants); and (2) that people treated using compression bandages or stockings are more likely to experience complete ulcer healing within 12 months compared with people with no compression (10 studies, 1215 participants): risk ratio for complete healing 1.77, 95% CI 1.41 to 2.21; I2 = 65% (8 studies with analysable data, 1120 participants); synthesis without meta-analysis suggests more completely-healed ulcers in compression bandages or stockings than in no compression (2 studies without analysable data, 95 participants). It is uncertain whether there is any difference in rates of adverse events between using compression bandages or stockings and no compression (very low-certainty evidence; 3 studies, 585 participants). Secondary outcomes Moderate-certainty evidence suggests that people using compression bandages or stockings probably have a lower mean pain score than those not using compression (four studies with 859 participants and another study with 69 ulcers): pooled mean difference -1.39, 95% CI -1.79 to -0.98; I2 = 65% (two studies with 426 participants and another study with 69 ulcers having analysable data); synthesis without meta-analysis suggests a reduction in leg ulcer pain in compression bandages or stockings, compared with no compression (two studies without analysable data, 433 participants). Compression bandages or stockings versus no compression may improve disease-specific quality of life, but not all aspects of general health status during the follow-up of 12 weeks to 12 months (four studies with 859 participants; low-certainty evidence). It is uncertain if the use of compression bandages or stockings is more cost-effective than not using them (three studies with 486 participants; very low-certainty evidence). AUTHORS' CONCLUSIONS: If using compression bandages or stockings, people with venous leg ulcers probably experience complete wound healing more quickly, and more people have wounds completely healed. The use of compression bandages or stockings probably reduces pain and may improve disease-specific quality of life. There is uncertainty about adverse effects, and cost effectiveness. Future research should focus on comparing alternative bandages and stockings with the primary endpoint of time to complete wound healing alongside adverse events including pain score, and health-related quality of life, and should incorporate cost-effectiveness analysis where possible. Future studies should adhere to international standards of trial conduct and reporting.

Alternative reactive support surfaces (non-foam and non-air-filled) for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Reactive surfaces that are not made of foam or air cells can be used for preventing pressure ulcers. OBJECTIVES: To assess the effects of non-foam and non-air-filled reactive beds, mattresses or overlays compared with any other support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to non-foam or non-air-filled reactive beds, overlays or mattresses. Comparators were any beds, overlays or mattresses used. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. If a non-foam or non-air-filled surface was compared with surfaces that were not clearly specified, then the included study was recorded and described but not considered further in any data analyses. MAIN RESULTS: We included 20 studies (4653 participants) in this review. Most studies were small (median study sample size: 198 participants). The average participant age ranged from 37.2 to 85.4 years (median: 72.5 years). Participants were recruited from a wide range of care settings but were mainly from acute care settings. Almost all studies were conducted in Europe and America. Of the 20 studies, 11 (2826 participants) included surfaces that were not well described and therefore could not be fully classified. We synthesised data for the following 12 comparisons: (1) reactive water surfaces versus alternating pressure (active) air surfaces (three studies with 414 participants), (2) reactive water surfaces versus foam surfaces (one study with 117 participants), (3) reactive water surfaces versus reactive air surfaces (one study with 37 participants), (4) reactive water surfaces versus reactive fibre surfaces (one study with 87 participants), (5) reactive fibre surfaces versus alternating pressure (active) air surfaces (four studies with 384 participants), (6) reactive fibre surfaces versus foam surfaces (two studies with 228 participants), (7) reactive gel surfaces on operating tables followed by foam surfaces on ward beds versus alternating pressure (active) air surfaces on operating tables and subsequently on ward beds (two studies with 415 participants), (8) reactive gel surfaces versus reactive air surfaces (one study with 74 participants), (9) reactive gel surfaces versus foam surfaces (one study with 135 participants), (10) reactive gel surfaces versus reactive gel surfaces (one study with 113 participants), (11) reactive foam and gel surfaces versus reactive gel surfaces (one study with 166 participants) and (12) reactive foam and gel surfaces versus foam surfaces (one study with 91 participants). Of the 20 studies, 16 (80%) presented findings which were considered to be at high overall risk of bias. PRIMARY OUTCOME: Pressure ulcer incidence We did not find analysable data for two comparisons: reactive water surfaces versus foam surfaces, and reactive water surfaces versus reactive fibre surfaces. Reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds (14/205 (6.8%)) may increase the proportion of people developing a new pressure ulcer compared with alternating pressure (active) air surfaces applied on both operating tables and hospital beds (3/210 (1.4%) (risk ratio 4.53, 95% confidence interval 1.31 to 15.65; 2 studies, 415 participants; I2 = 0%; low-certainty evidence). For all other comparisons, it is uncertain whether there is a difference in the proportion of participants developing new pressure ulcers as all data were of very low certainty. Included studies did not report time to pressure ulcer incidence for any comparison in this review. Secondary outcomes Support-surface-associated patient comfort: the included studies provide data on this outcome for one comparison. It is uncertain if there is a difference in patient comfort between alternating pressure (active) air surfaces and reactive fibre surfaces (one study with 187 participants; very low-certainty evidence). All reported adverse events: there is evidence on this outcome for one comparison. It is uncertain if there is a difference in adverse events between reactive gel surfaces followed by foam surfaces and alternating pressure (active) air surfaces applied on both operating tables and hospital beds (one study with 198 participants; very low-certainty evidence). We did not find any health-related quality of life or cost-effectiveness evidence for any comparison in this review. AUTHORS' CONCLUSIONS: Current evidence is generally uncertain about the differences between non-foam and non-air-filled reactive surfaces and other surfaces in terms of pressure ulcer incidence, patient comfort, adverse effects, health-related quality of life and cost-effectiveness. Reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds may increase the risk of having new pressure ulcers compared with alternating pressure (active) air surfaces applied on both operating tables and hospital beds. Future research in this area should consider evaluation of the most important support surfaces from the perspective of decision-makers. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Trials should be designed to minimise the risk of detection bias; for example, by using digital photography and adjudicators of the photographs being blinded to group allocation. Further review using network meta-analysis will add to the findings reported here.

ANTECEDENTES: Las úlceras por presión (también conocidas como úlceras y escaras de decúbito) son lesiones localizadas en la piel o en los tejidos blandos subyacentes, o en ambos, causadas por la presión, el cizallamiento o la fricción no aliviados. Las superficies estáticas que no son de espuma o celdas de aire se pueden utilizar para prevenir las úlceras por presión. OBJETIVOS: Evaluar los efectos de las camas, los colchones o los sobrecolchones estáticos sin espuma y sin aire en comparación con cualquier otra superficie especial para el manejo de la presión (SEMP) o sobre la incidencia de las úlceras por presión en cualquier población y en cualquier contexto. MÉTODOS DE BÚSQUEDA: En noviembre de 2019 se hicieron búsquedas en el Registro especializado del Grupo Cochrane de Heridas (Cochrane Wounds), en el Registro Cochrane central de ensayos controlados (Cochrane Central Register of Controlled Trials, CENTRAL); Ovid MEDLINE (incluido In­Process & Other Non­Indexed Citations); Ovid Embase y EBSCO CINAHL Plus. También se buscaron estudios en curso y no publicados en los registros de ensayos clínicos, y se examinaron las listas de referencias de los estudios incluidos pertinentes, así como de las revisiones, los metanálisis y los informes de tecnología sanitaria para identificar estudios adicionales. No hubo restricciones en cuanto al idioma, la fecha de publicación ni el contexto de los estudios. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos controlados aleatorizados que asignaron a participantes de cualquier edad a camas, colchones o sobrecolchones estáticos sin espuma y sin aire. Los comparadores fueron todas las camas, sobrecolchones o colchones utilizados. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Al menos dos autores de la revisión evaluaron de forma independiente los ensayos según criterios de inclusión predeterminados. Se realizó la extracción de los datos, la evaluación del riesgo de sesgo mediante la herramienta Cochrane "Risk of bias" y la evaluación de la certeza de la evidencia según el método Grading of Recommendations, Assessment, Development and Evaluations. Si se comparaba una superficie sin espuma o sin aire con superficies que no estaban claramente especificadas, se registraba y describía el estudio incluido, pero no se tenía en cuenta en ningún análisis de datos. RESULTADOS PRINCIPALES: En esta revisión se incluyeron 20 estudios (4653 participantes). La mayoría de los estudios eran pequeños (mediana del tamaño muestral de los estudios: 198 participantes). La edad promedio de los participantes varió entre 37,2 y 85,4 años (mediana: 72,5 años). Los participantes se reclutaron en una amplia variedad de ámbitos asistenciales, pero principalmente en ámbitos de cuidados intensivos y de agudos. Casi todos los estudios se realizaron en Europa y América. De los 20 estudios, 11 (2826 participantes) incluían superficies que no estaban bien descritas y, por lo tanto, no se podían clasificar completamente. Se resumieron los datos de las 12 comparaciones siguientes: (1) superficies de agua estáticas versus superficies de aire de presión alternante (activas) (tres estudios con 414 participantes), (2) superficies de agua estáticas versus superficies de espuma (un estudio con 117 participantes), (3) superficies de agua estáticas versus superficies de aire estáticas (un estudio con 37 participantes), (4) superficies de agua estáticas versus superficies de fibras estáticas (un estudio con 87 participantes), (5) superficies de fibras estáticas versus superficies de aire de presión alternante (activas) (cuatro estudios con 384 participantes), (6) superficies de fibras estáticas versus superficies de espuma (dos estudios con 228 participantes), (7) superficies de gel estáticas en las mesas de operaciones, seguidas de superficies de espuma en las camas de las salas, versus superficies de aire de presión alternante (activas) en las mesas de operaciones y posteriormente en las camas de las salas (dos estudios con 415 participantes), (8) superficies de gel estáticas versus superficies de aire estáticas (un estudio con 74 participantes) (9) superficies de gel estáticas versus superficies de espuma (un estudio con 135 participantes), (10) superficies de gel estáticas versus superficies de gel estáticas (un estudio con 113 participantes), (11) superficies de espuma y gel estáticas versus superficies de gel estáticas (un estudio con 166 participantes) y (12) superficies de espuma y gel estáticas versus superficies de espuma (un estudio con 91 participantes). De los 20 estudios, 16 (80%) presentaron resultados que se consideraron con alto riesgo general de sesgo. Desenlace principal: incidencia de las úlceras por presión No se encontraron datos analizables para dos comparaciones: superficies de agua estáticas versus superficies de espuma, ni superficies de agua estáticas versus superficies de fibras estáticas. Las superficies de gel estáticas utilizadas en las mesas de operaciones seguidas de las superficies de espuma aplicadas en las camas de hospital (14/205 [6,8%]) podrían aumentar la proporción de personas que presentan una nueva úlcera por presión en comparación con las superficies de aire de presión alternante (activas) aplicadas en las mesas de operaciones y en las camas de hospital (3/210 [1,4%]) (razón de riesgos 4,53; intervalo de confianza del 95%: 1,31 a 15,65; dos estudios, 415 participantes; I2 = 0%; evidencia de certeza baja). Para todas las demás comparaciones, no hay certeza de que haya una diferencia en la proporción de participantes que presentan nuevas úlceras por presión, ya que todos los datos eran de certeza muy baja. Los estudios incluidos no informaron el tiempo hasta la incidencia de las úlceras por presión para ninguna comparación en esta revisión. Desenlaces secundarios Comodidad del paciente asociada con la SEMP: los estudios incluidos proporcionan datos sobre este desenlace para una comparación. No está claro si existe una diferencia en la comodidad del paciente entre las superficies de aire de presión alternante (activas) y las superficies de fibras estáticas (un estudio con 187 participantes; evidencia de certeza muy baja). Todos los eventos adversos informados: hay evidencia sobre este desenlace para una comparación. No se sabe si existe una diferencia en los eventos adversos entre las superficies de gel estáticas seguidas de superficies de espuma y las superficies de aire de presión alternante (activas) aplicadas tanto en las mesas de operaciones como en las camas de hospital (un estudio con 198 participantes; evidencia de certeza muy baja). No se encontró evidencia acerca de la calidad de vida relacionada con la salud ni de la coste­efectividad para ninguna comparación en esta revisión. CONCLUSIONES DE LOS AUTORES: Por lo general no se desconoce la evidencia actual sobre las diferencias entre las superficies estáticas sin espuma y sin aire y otras superficies en términos de la incidencia de las úlceras por presión, la comodidad del paciente, los efectos adversos, la calidad de vida relacionada con la salud y la coste­efectividad. Las superficies de gel estáticas utilizadas en las mesas de operaciones, seguidas de las superficies de espuma aplicadas en las camas de hospital, podrían aumentar el riesgo de aparición de nuevas úlceras por presión en comparación con las superficies de aire de presión alternante (activas) aplicadas en las mesas de operaciones y en las camas de hospital. Los estudios de investigación futuros en este campo deberían considerar la evaluación de las SEMP más importantes desde la perspectiva de aquellos que toman decisiones. En los estudios futuros se deben considerar los desenlaces de tiempo hasta el evento, la evaluación cuidadosa de los eventos adversos y la evaluación de la coste­efectividad a nivel de ensayo. Los ensayos deben estar diseñados para minimizar el riesgo de sesgo de detección; por ejemplo, con el uso de fotografía digital y el cegamiento de los adjudicatarios de las fotografías a la asignación a los grupos. Una revisión posterior mediante metanálisis en red ampliará los resultados aquí proporcionados.

Foam surfaces for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Foam surfaces (beds, mattresses or overlays) are widely used with the aim of preventing pressure ulcers. OBJECTIVES: To assess the effects of foam beds, mattresses or overlays compared with any support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to foam beds, mattresses or overlays. Comparators were any beds, mattresses or overlays. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. If a foam surface was compared with surfaces that were not clearly specified, then the included study was recorded and described but not considered further in any data analyses. MAIN RESULTS: We included 29 studies (9566 participants) in the review. Most studies were small (median study sample size: 101 participants). The average age of participants ranged from 47.0 to 85.3 years (median: 76.0 years). Participants were mainly from acute care settings. We analysed data for seven comparisons in the review: foam surfaces compared with: (1) alternating pressure air surfaces, (2) reactive air surfaces, (3) reactive fibre surfaces, (4) reactive gel surfaces, (5) reactive foam and gel surfaces, (6) reactive water surfaces, and (7) another type of foam surface. Of the 29 included studies, 17 (58.6%) presented findings which were considered at high overall risk of bias. PRIMARY OUTCOME: pressure ulcer incidence Low-certainty evidence suggests that foam surfaces may increase the risk of developing new pressure ulcers compared with (1) alternating pressure (active) air surfaces (risk ratio (RR) 1.59, 95% confidence interval (CI) 0.86 to 2.95; I2 = 63%; 4 studies, 2247 participants), and (2) reactive air surfaces (RR 2.40, 95% CI 1.04 to 5.54; I2 = 25%; 4 studies, 229 participants). We are uncertain regarding the difference in pressure ulcer incidence in people treated with foam surfaces and the following surfaces: (1) reactive fibre surfaces (1 study, 68 participants); (2) reactive gel surfaces (1 study, 135 participants); (3) reactive gel and foam surfaces (1 study, 91 participants); and (4) another type of foam surface (6 studies, 733 participants). These had very low-certainty evidence. Included studies have data on time to pressure ulcer development for two comparisons. When time to ulcer development is considered using hazard ratios, the difference in the risk of having new pressure ulcers, over 90 days' follow-up, between foam surfaces and alternating pressure air surfaces is uncertain (2 studies, 2105 participants; very low-certainty evidence). Two further studies comparing different types of foam surfaces also reported time-to-event data, suggesting that viscoelastic foam surfaces with a density of 40 to 60 kg/m3 may decrease the risk of having new pressure ulcers over 11.5 days' follow-up compared with foam surfaces with a density of 33 kg/m3 (1 study, 62 participants); and solid foam surfaces may decrease the risk of having new pressure ulcers over one month's follow-up compared with convoluted foam surfaces (1 study, 84 participants). Both had low-certainty evidence. There was no analysable data for the comparison of foam surfaces with reactive water surfaces (one study with 117 participants). Secondary outcomes Support-surface-associated patient comfort: the review contains data for three comparisons for this outcome. It is uncertain if there is a difference in patient comfort measure between foam surfaces and alternating pressure air surfaces (1 study, 76 participants; very low-certainty evidence); foam surfaces and reactive air surfaces (1 study, 72 participants; very low-certainty evidence); and different types of foam surfaces (4 studies, 669 participants; very low-certainty evidence). All reported adverse events: the review contains data for two comparisons for this outcome. We are uncertain about differences in adverse effects between foam surfaces and alternating pressure (active) air surfaces (3 studies, 2181 participants; very low-certainty evidence), and between foam surfaces and reactive air surfaces (1 study, 72 participants; very low-certainty evidence). Health-related quality of life: only one study reported data on this outcome. It is uncertain if there is a difference (low-certainty evidence) between foam surfaces and alternating pressure (active) air surfaces in health-related quality of life measured with two different questionnaires, the EQ-5D-5L (267 participants) and the PU-QoL-UI (233 participants). Cost-effectiveness: one study reported trial-based cost-effectiveness evaluations. Alternating pressure (active) air surfaces are probably more cost-effective than foam surfaces in preventing pressure ulcer incidence (2029 participants; moderate-certainty evidence). AUTHORS' CONCLUSIONS: Current evidence suggests uncertainty about the differences in pressure ulcer incidence, patient comfort, adverse events and health-related quality of life between using foam surfaces and other surfaces (reactive fibre surfaces, reactive gel surfaces, reactive foam and gel surfaces, or reactive water surfaces). Foam surfaces may increase pressure ulcer incidence compared with alternating pressure (active) air surfaces and reactive air surfaces. Alternating pressure (active) air surfaces are probably more cost-effective than foam surfaces in preventing new pressure ulcers. Future research in this area should consider evaluation of the most important support surfaces from the perspective of decision-makers. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Trials should be designed to minimise the risk of detection bias; for example, by using digital photography and by blinding adjudicators of the photographs to group allocation. Further review using network meta-analysis will add to the findings reported here.

ANTECEDENTES: Las úlceras por presión (también conocidas como úlceras de decúbito) son lesiones localizadas en la piel o en los tejidos blandos subyacentes, o en ambos, y causadas por la presión, el cizallamiento o la fricción no aliviados. Las superficies de espuma (camas, colchones o sobrecolchones) se utilizan ampliamente con el objetivo de prevenir las úlceras por presión. OBJETIVOS: Evaluar los efectos de las camas, los colchones o los sobrecolchones de espuma en comparación con cualquier superficie especial de manejo de presión (SEMP) sobre la incidencia de las úlceras por presión en cualquier población y en cualquier ámbito. MÉTODOS DE BÚSQUEDA: En noviembre de 2019 se realizaron búsquedas en el Registro especializado del Grupo Cochrane de Heridas (Cochrane Wounds); en el Registro Cochrane central de ensayos controlados (Cochrane Central Register of Controlled Trials; CENTRAL); en Ovid MEDLINE (incluido In­Process & Other Non­Indexed Citations); en Ovid Embase y en EBSCO CINAHL Plus. También se buscaron estudios en curso y no publicados en los registros de ensayos clínicos, y se examinaron las listas de referencias de los estudios incluidos pertinentes, así como de las revisiones, los metanálisis y los informes de tecnología sanitaria para identificar estudios adicionales. No hubo restricciones en cuanto al idioma, la fecha de publicación ni el contexto de los estudios. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos controlados aleatorizados que asignaron a participantes de cualquier edad a camas, colchones o sobrecolchones de espuma. Los comparadores fueron cualquier cama, colchón o sobrecolchón. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Al menos dos autores de la revisión evaluaron de forma independiente los ensayos según los criterios de inclusión predeterminados. Se realizó la extracción de los datos, la evaluación del "riesgo de sesgo" mediante la herramienta Cochrane "Risk of bias" y la evaluación de la certeza de la evidencia según el método Grading of Recommendations, Assessment, Development and Evaluations. Si se comparaba una superficie de espuma con superficies que no estaban claramente especificadas, se registraba y describía el estudio incluido, pero no se tenía en cuenta en ningún análisis de datos. RESULTADOS PRINCIPALES: En la revisión se incluyeron 29 estudios (9566 participantes). La mayoría de los estudios eran pequeños (mediana del tamaño muestral de los estudios: 101 participantes). El promedio de edad de los participantes varió entre 47,0 y 85,3 años (mediana: 76,0 años). Los participantes procedían principalmente de ámbitos de cuidados intensivos y de agudos. En la revisión se analizaron los datos de siete comparaciones: superficies de espuma comparadas con: (1) superficies de aire de presión alternante, (2) superficies de aire estáticas, (3) superficies de fibra estáticas, (4) superficies de gel estáticas, (5) superficies de espuma y gel estáticas, (6) superficies de agua estáticas y (7) otro tipo de superficie de espuma. De los 29 estudios incluidos, 17 (58,6%) presentaron resultados que se consideraron con alto riesgo general de sesgo. Desenlace principal: incidencia de úlceras por presión Evidencia de certeza baja indica que las superficies de espuma podrían aumentar el riesgo de desarrollar nuevas úlceras por presión en comparación con (1) las superficies de aire de presión alternante (activas) (razón de riesgos [RR] 1,59; intervalo de confianza [IC] del 95%: 0,86 a 2,95; I2 = 63%; cuatro estudios, 2247 participantes) y (2) las superficies de aire estáticas (RR 2,40; IC del 95%: 1,04 a 5,54; I2 = 25%; cuatro estudios, 229 participantes). No hay certeza acerca de la diferencia en la incidencia de las úlceras por presión en las personas tratadas con superficies de espuma y las siguientes superficies: (1) superficies de fibras estáticas (un estudio, 68 participantes); (2) superficies de gel estáticas (un estudio, 135 participantes); (3) superficies estáticas de gel y espuma (un estudio, 91 participantes); y (4) otro tipo de superficies de espuma (seis estudios, 733 participantes). Al respecto se cuenta con evidencia de certeza muy baja. Los estudios incluidos cuentan con datos sobre el tiempo hasta la aparición de úlceras por presión para dos comparaciones. Cuando se considera el tiempo hasta la aparición de la úlcera con el uso de los cocientes de riesgos instantáneos, no está clara la diferencia en el riesgo de tener nuevas úlceras por presión, durante 90 días de seguimiento, entre las superficies de espuma y las de aire de presión alternante (dos estudios, 2105 participantes; evidencia de certeza muy baja). Otros dos estudios que compararon diferentes tipos de superficies de espuma también proporcionaron datos sobre el tiempo hasta el evento, e indicaron que las superficies de espuma viscoelástica con una densidad de 40 a 60 kg/m3 podrían disminuir el riesgo de presentar nuevas úlceras por presión durante 11,5 días de seguimiento en comparación con las superficies de espuma con una densidad de 33 kg/m3 (un estudio, 62 participantes) y las superficies de espuma sólida podrían disminuir el riesgo de presentar nuevas úlceras por presión durante un mes de seguimiento en comparación con las superficies de espuma alveolar (un estudio, 84 participantes). Ambos con evidencia de certeza baja. No hubo datos que se pudieran analizar para la comparación de las superficies de espuma con las de agua estáticas (un estudio con 117 participantes). Desenlaces secundarios Comodidad del paciente asociada con la SEMP: la revisión contiene datos de tres comparaciones para este desenlace. No se sabe si existe una diferencia en la medida de comodidad del paciente entre las superficies de espuma y las superficies de aire de presión alternante (un estudio, 76 participantes; evidencia de certeza muy baja); las superficies de espuma y las superficies de aire estáticas (un estudio, 72 participantes; evidencia de certeza muy baja); y los diferentes tipos de superficies de espuma (cuatro estudios, 669 participantes; evidencia de certeza muy baja). Todos los eventos adversos informados: la revisión contiene datos de dos comparaciones para este desenlace. No están claras las diferencias en los efectos adversos entre las superficies de espuma y las superficies de aire de presión alternante (activas) (tres estudios, 2181 participantes; evidencia de certeza muy baja), ni entre las superficies de espuma y las superficies de aire estáticas (un estudio, 72 participantes; evidencia de certeza muy baja). Calidad de vida relacionada con la salud: sólo un estudio proporcionó datos sobre este desenlace. No se sabe si existe una diferencia (evidencia de certeza baja) entre las superficies de espuma y las superficies de aire de presión alternante (activas) en la calidad de vida relacionada con la salud medida con dos cuestionarios diferentes, el EQ­5D­5L (267 participantes) y el PU­QoL­UI (233 participantes). Coste­efectividad: un estudio proporcionó evaluaciones de coste­efectividad a nivel de ensayo. Las superficies de aire de presión alternante (activas) son probablemente más coste­efectivas que las superficies de espuma en la prevención de la incidencia de las úlceras por presión (2029 participantes; evidencia de certeza moderada). CONCLUSIONES DE LOS AUTORES: La evidencia actual indica que no hay certeza acerca de las diferencias en la incidencia de las úlceras por presión, la comodidad del paciente, los eventos adversos ni la calidad de vida relacionada con la salud entre el uso de superficies de espuma y otras SEMP (superficies de fibras estáticas, superficies de gel estáticas, superficies de espuma y gel estáticas o superficies de agua estáticas). Las superficies de espuma podrían aumentar la incidencia de las úlceras por presión en comparación con las superficies de aire de presión alternante (activas) y las superficies de aire estáticas. Las superficies de aire de presión alternante (activas) son probablemente más coste­efectivas que las superficies de espuma para prevenir nuevas úlceras por presión. Los estudios de investigación futuros en este campo deberían considerar la evaluación de las SEMP más importantes desde la perspectiva de los responsables de la toma de decisiones. En los estudios futuros se deben considerar los desenlaces de tiempo hasta el evento, la evaluación cuidadosa de los eventos adversos y la evaluación de la coste­efectividad a nivel de ensayo. Los ensayos deben estar diseñados para minimizar el riesgo de sesgo de detección; por ejemplo, con el uso de fotografía digital y el cegamiento de los adjudicatarios de las fotografías a la asignación a los grupos. Una revisión posterior mediante metanálisis en red ampliará los resultados aquí proporcionados.

Beds, overlays and mattresses for treating pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Beds, overlays or mattresses are widely used with the aim of treating pressure ulcers. OBJECTIVES: To assess the effects of beds, overlays and mattresses on pressure ulcer healing in people with pressure ulcers of any stage, in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to pressure-redistributing beds, overlays or mattresses. Comparators were any beds, overlays or mattresses that were applied for treating pressure ulcers. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: We included 13 studies (972 participants) in the review. Most studies were small (median study sample size: 72 participants). The average age of participants ranged from 64.0 to 86.5 years (median: 82.7 years) and all studies recruited people with existing pressure ulcers (the baseline ulcer area size ranging from 4.2 to 18.6 cm2,median 6.6 cm2). Participants were recruited from acute care settings (six studies) and community and long-term care settings (seven studies). Of the 13 studies, three (224 participants) involved surfaces that were not well described and therefore could not be classified. Additionally, six (46.2%) of the 13 studies presented findings which were considered at high overall risk of bias. We synthesised data for four comparisons in the review: alternating pressure (active) air surfaces versus foam surfaces; reactive air surfaces versus foam surfaces; reactive water surfaces versus foam surfaces, and a comparison between two types of alternating pressure (active) air surfaces. We summarise key findings for these four comparisons below. (1) Alternating pressure (active) air surfaces versus foam surfaces: we are uncertain if there is a difference between alternating pressure (active) air surfaces and foam surfaces in the proportion of participants whose pressure ulcers completely healed (two studies with 132 participants; the reported risk ratio (RR) in one study was 0.97, 95% confidence interval (CI) 0.26 to 3.58). There is also uncertainty for the outcomes of patient comfort (one study with 83 participants) and adverse events (one study with 49 participants). These outcomes have very low-certainty evidence. Included studies did not report time to complete ulcer healing, health-related quality of life, or cost effectiveness. (2) Reactive air surfaces versus foam surfaces: it is uncertain if there is a difference in the proportion of participants with completely healed pressure ulcers between reactive air surfaces and foam surfaces (RR 1.32, 95% CI 0.96 to 1.80; I2 = 0%; 2 studies, 156 participants; low-certainty evidence). When time to complete pressure ulcer healing is considered using a hazard ratio, data from one small study (84 participants) suggests a greater hazard for complete ulcer healing on reactive air surfaces (hazard ratio 2.66, 95% CI 1.34 to 5.17; low-certainty evidence). These results are sensitive to the choice of outcome measure so should be interpreted as uncertain. We are also uncertain whether there is any difference between these surfaces in patient comfort responses (1 study, 72 participants; very low-certainty evidence) and in adverse events (2 studies, 156 participants; low-certainty evidence). There is low-certainty evidence that reactive air surfaces may cost an extra 26 US dollars for every ulcer-free day in the first year of use (1 study, 87 participants). Included studies did not report health-related quality of life. (3) Reactive water surfaces versus foam surfaces: it is uncertain if there is a difference between reactive water surfaces and foam surfaces in the proportion of participants with healed pressure ulcers (RR 1.07, 95% CI 0.70 to 1.63; 1 study, 101 participants) and in adverse events (1 study, 120 participants). All these have very low-certainty evidence. Included studies did not report time to complete ulcer healing, patient comfort, health-related quality of life, or cost effectiveness. (4) Comparison between two types of alternating pressure (active) air surfaces: it is uncertain if there is a difference between Nimbus and Pegasus alternating pressure (active) air surfaces in the proportion of participants with healed pressure ulcers, in patient comfort responses and in adverse events: each of these outcomes had four studies (256 participants) but very low-certainty evidence. Included studies did not report time to complete ulcer healing, health-related quality of life, or cost effectiveness. AUTHORS' CONCLUSIONS: We are uncertain about the relative effects of most different pressure-redistributing surfaces for pressure ulcer healing (types directly compared are alternating pressure air surfaces versus foam surfaces, reactive air surfaces versus foam surfaces, reactive water surfaces versus foam surfaces, and Nimbus versus Pegasus alternating pressure (active) air surfaces). There is also uncertainty regarding the effects of these different surfaces on the outcomes of comfort and adverse events. However, people using reactive air surfaces may be more likely to have pressure ulcers completely healed than those using foam surfaces over 37.5 days' follow-up, and reactive air surfaces may cost more for each ulcer-free day than foam surfaces. Future research in this area could consider the evaluation of alternating pressure air surfaces versus foam surfaces as a high priority. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Further review using network meta-analysis will add to the findings reported here.

Alternating pressure (active) air surfaces for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Alternating pressure (active) air surfaces are widely used with the aim of preventing pressure ulcers. OBJECTIVES: To assess the effects of alternating pressure (active) air surfaces (beds, mattresses or overlays) compared with any support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to alternating pressure (active) air beds, overlays or mattresses. Comparators were any beds, overlays or mattresses. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: We included 32 studies (9058 participants) in the review. Most studies were small (median study sample size: 83 participants). The average age of participants ranged from 37.2 to 87.0 years (median: 69.1 years). Participants were largely from acute care settings (including accident and emergency departments). We synthesised data for six comparisons in the review: alternating pressure (active) air surfaces versus: foam surfaces, reactive air surfaces, reactive water surfaces, reactive fibre surfaces, reactive gel surfaces used in the operating room followed by foam surfaces used on the ward bed, and another type of alternating pressure air surface. Of the 32 included studies, 25 (78.1%) presented findings which were considered at high overall risk of bias. PRIMARY OUTCOME: pressure ulcer incidence Alternating pressure (active) air surfaces may reduce the proportion of participants developing a new pressure ulcer compared with foam surfaces (risk ratio (RR) 0.63, 95% confidence interval (CI) 0.34 to 1.17; I2 = 63%; 4 studies, 2247 participants; low-certainty evidence). Alternating pressure (active) air surfaces applied on both operating tables and hospital beds may reduce the proportion of people developing a new pressure ulcer compared with reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds (RR 0.22, 95% CI 0.06 to 0.76; I2 = 0%; 2 studies, 415 participants; low-certainty evidence). It is uncertain whether there is a difference in the proportion of people developing new pressure ulcers between alternating pressure (active) air surfaces and the following surfaces, as all these comparisons have very low-certainty evidence: (1) reactive water surfaces; (2) reactive fibre surfaces; and (3) reactive air surfaces. The comparisons between different types of alternating pressure air surfaces are presented narratively. Overall, all comparisons suggest little to no difference between these surfaces in pressure ulcer incidence (7 studies, 2833 participants; low-certainty evidence). Included studies have data on time to pressure ulcer incidence for three comparisons. When time to pressure ulcer development is considered using a hazard ratio (HR), it is uncertain whether there is a difference in the risk of developing new pressure ulcers, over 90 days' follow-up, between alternating pressure (active) air surfaces and foam surfaces (HR 0.41, 95% CI 0.10 to 1.64; I2 = 86%; 2 studies, 2105 participants; very low-certainty evidence). For the comparison with reactive air surfaces, there is low-certainty evidence that people treated with alternating pressure (active) air surfaces may have a higher risk of developing an incident pressure ulcer than those treated with reactive air surfaces over 14 days' follow-up (HR 2.25, 95% CI 1.05 to 4.83; 1 study, 308 participants). Neither of the two studies with time to ulcer incidence data suggested a difference in the risk of developing an incident pressure ulcer over 60 days' follow-up between different types of alternating pressure air surfaces. Secondary outcomes The included studies have data on (1) support-surface-associated patient comfort for comparisons involving foam surfaces, reactive air surfaces, reactive fibre surfaces and alternating pressure (active) air surfaces; (2) adverse events for comparisons involving foam surfaces, reactive gel surfaces and alternating pressure (active) air surfaces; and (3) health-related quality of life outcomes for the comparison involving foam surfaces. However, all these outcomes and comparisons have low or very low-certainty evidence and it is uncertain whether there are any differences in these outcomes. Included studies have data on cost effectiveness for two comparisons. Moderate-certainty evidence suggests that alternating pressure (active) air surfaces are probably more cost-effective than foam surfaces (1 study, 2029 participants) and that alternating pressure (active) air mattresses are probably more cost-effective than overlay versions of this technology for people in acute care settings (1 study, 1971 participants). AUTHORS' CONCLUSIONS: Current evidence is uncertain about the difference in pressure ulcer incidence between using alternating pressure (active) air surfaces and other surfaces (reactive water surfaces, reactive fibre surfaces and reactive air surfaces). Alternating pressure (active) air surfaces may reduce pressure ulcer risk compared with foam surfaces and reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds. People using alternating pressure (active) air surfaces may be more likely to develop new pressure ulcers over 14 days' follow-up than those treated with reactive air surfaces in the nursing home setting; but as the result is sensitive to the choice of outcome measure it should be interpreted cautiously. Alternating pressure (active) air surfaces are probably more cost-effective than reactive foam surfaces in preventing new pressure ulcers. Future studies should include time-to-event outcomes and assessment of adverse events and trial-level cost-effectiveness. Further review using network meta-analysis will add to the findings reported here.

Reactive air surfaces for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Reactive air surfaces (beds, mattresses or overlays) can be used for preventing pressure ulcers. OBJECTIVES: To assess the effects of reactive air beds, mattresses or overlays compared with any support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to reactive air beds, overlays or mattresses. Comparators were any beds, overlays or mattresses that were applied for preventing pressure ulcers. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. If a reactive air surface was compared with surfaces that were not clearly specified, then we recorded and described the concerned study but did not included it in further data analyses. MAIN RESULTS: We included 17 studies (2604 participants) in this review. Most studies were small (median study sample size: 83 participants). The average participant age ranged from 56 to 87 years (median: 72 years). Participants were recruited from a wide range of care settings with the majority being acute care settings. Almost all studies were conducted in the regions of Europe and America. Of the 17 included studies, two (223 participants) compared reactive air surfaces with surfaces that were not well described and therefore could not be classified. We analysed data for five comparisons: reactive air surfaces compared with (1) alternating pressure (active) air surfaces (seven studies with 1728 participants), (2) foam surfaces (four studies with 229 participants), (3) reactive water surfaces (one study with 37 participants), (4) reactive gel surfaces (one study with 66 participants), and (5) another type of reactive air surface (two studies with 223 participants). Of the 17 studies, seven (41.2%) presented findings which were considered at high overall risk of bias. PRIMARY OUTCOME: Pressure ulcer incidence Reactive air surfaces may reduce the proportion of participants developing a new pressure ulcer compared with foam surfaces (risk ratio (RR) 0.42; 95% confidence interval (CI) 0.18 to 0.96; I2 = 25%; 4 studies, 229 participants; low-certainty evidence). It is uncertain if there is a difference in the proportions of participants developing a new pressure ulcer on reactive air surfaces compared with: alternating pressure (active) air surfaces (6 studies, 1648 participants); reactive water surfaces (1 study, 37 participants); reactive gel surfaces (1 study, 66 participants), or another type of reactive air surface (2 studies, 223 participants). Evidence for all these comparisons is of very low certainty. Included studies have data on time to pressure ulcer incidence for two comparisons. When time to pressure ulcer incidence is considered using a hazard ratio (HR), low-certainty evidence suggests that in the nursing home setting, people on reactive air surfaces may be less likely to develop a new pressure ulcer over 14 days' of follow-up than people on alternating pressure (active) air surfaces (HR 0.44; 95% CI 0.21 to 0.96; 1 study, 308 participants). It is uncertain if there is a difference in the hazard of developing new pressure ulcers between two types of reactive air surfaces (1 study, 123 participants; very low-certainty evidence). Secondary outcomes Support-surface-associated patient comfort: the included studies have data on this outcome for three comparisons. We could not pool any data as comfort outcome measures differed between included studies; therefore a narrative summary is provided. It is uncertain if there is a difference in patient comfort responses between reactive air surfaces and foam surfaces over the top of an alternating pressure (active) air surfaces (1 study, 72 participants), and between those using reactive air surfaces and those using alternating pressure (active) air surfaces (4 studies, 1364 participants). Evidence for these two comparisons is of very low certainty. It is also uncertain if there is a difference in patient comfort responses between two types of reactive air surfaces (1 study, 84 participants; low-certainty evidence). All reported adverse events: there were data on this outcome for one comparison: it is uncertain if there is a difference in adverse events between reactive air surfaces and foam surfaces (1 study, 72 participants; very low-certainty evidence). The included studies have no data for health-related quality of life and cost-effectiveness for all five comparisons. AUTHORS' CONCLUSIONS: Current evidence is uncertain regarding any differences in the relative effects of reactive air surfaces on ulcer incidence and patient comfort, when compared with reactive water surfaces, reactive gel surfaces, or another type of reactive air surface. Using reactive air surfaces may reduce the risk of developing new pressure ulcers compared with using foam surfaces. Also, using reactive air surfaces may reduce the risk of developing new pressure ulcers within 14 days compared with alternating pressure (active) air surfaces in people in a nursing home setting. Future research in this area should consider evaluation of the most important support surfaces from the perspective of decision-makers. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Trials should be designed to minimise the risk of detection bias; for example, by using digital photography and adjudicators of the photographs being blinded to group allocation. Further review using network meta-analysis will add to the findings reported here.

ANTECEDENTES: Las úlceras por presión (también conocidas como escaras o úlceras de decúbito) son lesiones localizadas en la piel o en los tejidos blandos subyacentes, o en ambos, causadas por la presión, el roce o la fricción no aliviados. Las superficies de aire estáticas (camas, colchones o sobrecolchones) se pueden utilizar para prevenir las úlceras por presión. OBJETIVOS: Evaluar los efectos de las camas, los colchones o los sobrecolchones de aire estáticos en comparación con cualquier superficie especial para el manejo de la presión (SEMP) sobre la incidencia de las úlceras por presión en cualquier población y en cualquier ámbito. MÉTODOS DE BÚSQUEDA: En noviembre de 2019 se hicieron búsquedas en el Registro especializado del Grupo Cochrane de Heridas (Cochrane Wounds), en el Registro Cochrane central de ensayos controlados (CENTRAL); Ovid MEDLINE (incluido In­Process & Other Non­Indexed Citations); Ovid Embase y EBSCO CINAHL Plus. También se buscaron estudios en curso y no publicados en los registros de ensayos clínicos, y se examinaron las listas de referencias de los estudios incluidos pertinentes, así como de las revisiones, los metanálisis y los informes de tecnología sanitaria para identificar estudios adicionales. No hubo restricciones en cuanto al idioma, la fecha de publicación ni el contexto de los estudios. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos controlados aleatorizados que asignaron a participantes de cualquier edad a camas, colchones o sobrecolchones de aire estáticos. Los comparadores fueron cualquier cama, colchón o sobrecolchón utilizados para prevenir las úlceras por presión. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Al menos dos autores de la revisión evaluaron de forma independiente los ensayos según criterios de inclusión predeterminados. Se realizó la extracción de los datos, la evaluación del riesgo de sesgo mediante la herramienta Cochrane "Risk of bias" y la evaluación de la certeza de la evidencia según el método Grading of Recommendations, Assessment, Development and Evaluations. Si se comparaba una superficie de aire estática con superficies que no estaban claramente especificadas, se registraba y describía el estudio en cuestión pero no se incluía en análisis de datos adicionales. RESULTADOS PRINCIPALES: En esta revisión se incluyeron 17 estudios (2604 participantes). La mayoría de los estudios eran pequeños (mediana del tamaño muestral de los estudios: 83 participantes). La media de edad de los participantes varió entre 56 y 87 años (mediana: 72 años). Los participantes fueron reclutados en una amplia variedad de ámbitos asistenciales, siendo la mayoría de ellos ámbitos de cuidados intensivos y de agudos. Casi todos los estudios se realizaron en las regiones de Europa y América. De los 17 estudios incluidos, dos (223 participantes) compararon superficies de aire estáticas con superficies que no estaban bien descritas y, por tanto, no pudieron clasificarse. Se analizaron los datos de cinco comparaciones: superficies de aire estáticas comparadas con (1) superficies de aire de presión alternante (activas) (siete estudios con 1728 participantes), (2) superficies de espuma (cuatro estudios con 229 participantes), (3) superficies de agua estáticas (un estudio con 37 participantes), (4) superficies de gel estáticas (un estudio con 66 participantes) y (5) otro tipo de superficies de aire estáticas (dos estudios con 223 participantes). De los 17 estudios incluidos, siete (41,2%) presentaron resultados que se consideraron con alto riesgo general de sesgo. Desenlace principal: incidencia de úlceras por presión Las superficies de aire estáticas podrían reducir la proporción de participantes que desarrollan nuevas úlceras por presión en comparación con las superficies de espuma (razón de riesgos [RR] 0,42; intervalo de confianza [IC] del 95%: 0,18 a 0,96; I2 = 25%; cuatro estudios, 229 participantes; evidencia de certeza baja). No se sabe si existe una diferencia en las proporciones de participantes que desarrollan una nueva úlcera por presión en superficies de aire estáticas en comparación con: superficies de aire de presión alternante (activas) (seis estudios, 1648 participantes); superficies de agua estáticas (un estudio, 37 participantes); superficies de gel estáticas (un estudio, 66 participantes) u otro tipo de superficies de aire estáticas (dos estudios, 223 participantes). La evidencia para todas estas comparaciones es de certeza muy baja. Los estudios incluidos cuentan con datos sobre el tiempo hasta la incidencia de úlceras por presión para dos comparaciones. Cuando el tiempo hasta la incidencia de la úlcera por presión se considera con el cociente de riesgos instantáneos (CRI), la evidencia de certeza baja indica que en el ámbito de las residencia de ancianos, las personas sobre superficies de aire estáticas podrían tener menos probabilidades de presentar una nueva úlcera por presión a lo largo de 14 días de seguimiento que las personas sobre superficies de aire de presión alternante (activas) (CRI 0,44; IC del 95%: 0,21 a 0,96; un estudio, 308 participantes). No se sabe si hay una diferencia en el riesgo de presentar nuevas úlceras por presión entre dos tipos de superficies de aire estáticas (un estudio, 123 participantes; evidencia de certeza muy baja). Desenlaces secundarios Comodidad del paciente asociada con la SEMP: los estudios incluidos contienen datos de tres comparaciones para este desenlace. No fue posible agrupar los datos puesto que las medidas de desenlace de comodidad difirieron entre los estudios incluidos; por lo tanto, se proporciona un resumen narrativo. No se sabe si existe una diferencia en las respuestas de comodidad del paciente entre las superficies de espuma y las superficies de aire estáticas sobre superficies de aire de presión alternante (activas) (un estudio, 72 participantes) ni entre aquellos que utilizaron superficies de aire estáticas y los que utilizaron superficies de aire de presión alternante (activas) (cuatro estudios, 1364 participantes). La evidencia para estas dos comparaciones es de certeza muy baja. Tampoco se sabe si hay una diferencia en las respuestas de comodidad de los pacientes entre dos tipos de superficies de aire estáticas (un estudio, 84 participantes; evidencia de certeza baja). Todos los eventos adversos notificados: hubo datos sobre este desenlace para una comparación: no se sabe si existe una diferencia en los eventos adversos entre las superficies de aire estáticas y las superficies de espuma (un estudio, 72 participantes; evidencia de certeza muy baja). Los estudios incluidos no tienen datos sobre la calidad de vida relacionada con la salud y la coste­efectividad para ninguna de las cinco comparaciones. CONCLUSIONES DE LOS AUTORES: La evidencia actual es incierta en cuanto a las diferencias en los efectos relativos de las superficies de aire estáticas sobre la incidencia de úlceras y la comodidad del paciente, cuando se compararon con las superficies de agua estáticas, las superficies de gel estáticas u otro tipo de superficies de aire estáticas. El uso de superficies de aire estáticas podría reducir el riesgo de aparición de nuevas úlceras por presión en comparación con el uso de superficies de espuma. Además, el uso de superficies de aire estáticas podría reducir el riesgo de aparición de nuevas úlceras por presión en los 14 días siguientes en comparación las superficies de aire de presión alternante (activas) en personas en una residencia de ancianos. Los estudios de investigación futuros en este campo deberían considerar la evaluación de las SEMP más importantes desde la perspectiva de aquellos que toman decisiones. En los estudios futuros se deben considerar los desenlaces de tiempo hasta el evento, la evaluación cuidadosa de los eventos adversos y la evaluación de la coste­efectividad a nivel de ensayo. Los ensayos deben estar diseñados para minimizar el riesgo de sesgo de detección; por ejemplo, con el uso de fotografía digital y el cegamiento de los adjudicatarios de las fotografías a la asignación a los grupos. Una revisión posterior mediante metanálisis en red ampliará los resultados aquí proporcionados.

Beds, overlays and mattresses for preventing and treating pressure ulcers: an overview of Cochrane Reviews and network meta-analysis.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Specific kinds of beds, overlays and mattresses are widely used with the aim of preventing and treating pressure ulcers. OBJECTIVES: To summarise evidence from Cochrane Reviews that assess the effects of beds, overlays and mattresses on reducing the incidence of pressure ulcers and on increasing pressure ulcer healing in any setting and population. To assess the relative effects of different types of beds, overlays and mattresses for reducing the incidence of pressure ulcers and increasing pressure ulcer healing in any setting and population. To cumulatively rank the different treatment options of beds, overlays and mattresses in order of their effectiveness in pressure ulcer prevention and treatment. METHODS: In July 2020, we searched the Cochrane Library. Cochrane Reviews reporting the effectiveness of beds, mattresses or overlays for preventing or treating pressure ulcers were eligible for inclusion in this overview. Two review authors independently screened search results and undertook data extraction and risk of bias assessment using the ROBIS tool. We summarised the reported evidence in an overview of reviews. Where possible, we included the randomised controlled trials from each included review in network meta-analyses. We assessed the relative effectiveness of beds, overlays and mattresses for preventing or treating pressure ulcers and their probabilities of being, comparably, the most effective treatment. We assessed the certainty of the evidence using the GRADE approach. MAIN RESULTS: We include six Cochrane Reviews in this overview of reviews, all at low or unclear risk of bias. Pressure ulcer prevention: four reviews (of 68 studies with 18,174 participants) report direct evidence for 27 pairwise comparisons between 12 types of support surface on the following outcomes: pressure ulcer incidence, time to pressure ulcer incidence, patient comfort response, adverse event rates, health-related quality of life, and cost-effectiveness. Here we focus on outcomes with some evidence at a minimum of low certainty. (1) Pressure ulcer incidence: our overview includes direct evidence for 27 comparisons that mostly (19/27) have very low-certainty evidence concerning reduction of pressure ulcer risk. We included 40 studies (12,517 participants; 1298 participants with new ulcers) in a network meta-analysis involving 13 types of intervention. Data informing the network are sparse and this, together with the high risk of bias in most studies informing the network, means most network contrasts (64/78) yield evidence of very low certainty. There is low-certainty evidence that, compared with foam surfaces (reference treatment), reactive air surfaces (e.g. static air overlays) (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.29 to 0.75), alternating pressure (active) air surfaces (e.g. alternating pressure air mattresses, large-celled ripple mattresses) (RR 0.63, 95% CI 0.42 to 0.93), and reactive gel surfaces (e.g. gel pads used on operating tables) (RR 0.47, 95% CI 0.22 to 1.01) may reduce pressure ulcer incidence. The ranking of treatments in terms of effectiveness is also of very low certainty for all interventions. It is unclear which treatment is best for preventing ulceration. (2) Time to pressure ulcer incidence: four reviews had direct evidence on this outcome for seven comparisons. We included 10 studies (7211 participants; 699 participants with new ulcers) evaluating six interventions in a network meta-analysis. Again, data from most network contrasts (13/15) are of very low certainty. There is low-certainty evidence that, compared with foam surfaces (reference treatment), reactive air surfaces may reduce the hazard of developing new pressure ulcers (hazard ratio (HR) 0.20, 95% CI 0.04 to 1.05). The ranking of all support surfaces for preventing pressure ulcers in terms of time to healing is uncertain. (3) Cost-effectiveness: this overview includes direct evidence for three comparisons. For preventing pressure ulcers, alternating pressure air surfaces are probably more cost-effective than foam surfaces (moderate-certainty evidence). Pressure ulcer treatment: two reviews (of 12 studies with 972 participants) report direct evidence for five comparisons on: complete pressure ulcer healing, time to complete pressure ulcer healing, patient comfort response, adverse event rates, and cost-effectiveness. Here we focus on outcomes with some evidence at a minimum of low certainty. (1) Complete pressure ulcer healing: our overview includes direct evidence for five comparisons. There is uncertainty about the relative effects of beds, overlays and mattresses on ulcer healing. The corresponding network meta-analysis (with four studies, 397 participants) had only three direct contrasts and a total of six network contrasts. Again, most network contrasts (5/6) have very low-certainty evidence. There was low-certainty evidence that more people with pressure ulcers may heal completely using reactive air surfaces than using foam surfaces (RR 1.32, 95% CI 0.96 to 1.80). We are uncertain which surfaces have the highest probability of being the most effective (all very low-certainty evidence). (2) Time to complete pressure ulcer healing: this overview includes direct evidence for one comparison: people using reactive air surfaces may be more likely to have healed pressure ulcers compared with those using foam surfaces in long-term care settings (HR 2.66, 95% CI 1.34 to 5.17; low-certainty evidence). (3) Cost-effectiveness: this overview includes direct evidence for one comparison: compared with foam surfaces, reactive air surfaces may cost an extra 26 US dollars for every ulcer-free day in the first year of use in long-term care settings (low-certainty evidence). AUTHORS' CONCLUSIONS: Compared with foam surfaces, reactive air surfaces may reduce pressure ulcer risk and may increase complete ulcer healing. Compared with foam surfaces, alternating pressure air surfaces may reduce pressure ulcer risk and are probably more cost-effective in preventing pressure ulcers. Compared with foam surfaces, reactive gel surfaces may reduce pressure ulcer risk, particularly for people in operating rooms and long-term care settings. There are uncertainties for the relative effectiveness of other support surfaces for preventing and treating pressure ulcers, and their efficacy ranking. More high-quality research is required; for example, for the comparison of reactive air surfaces with alternating pressure air surfaces. Future studies should consider time-to-event outcomes and be designed to minimise any risk of bias.

Protease activity as a prognostic factor for wound healing in complex wounds.

Healing mechanisms are disrupted in complex wounds. Proteases may persist longer in nonhealing wounds. We sought to investigate whether protease activity, protease inhibitor activity, or their combinations are independent prognostic factors for healing of complex wounds. We searched MEDLINE, EMBASE, CINAHL, and The Cochrane Library to March 2019. Study selection comprised longitudinal studies assessing the independent effect of proteases, their inhibitors or ratios of the two, on healing of complex wounds, while controlling for confounding factors. Two reviewers independently extracted data and assessed risk of bias. We conducted meta-analyses separately for proteases, inhibitors, and ratios. We graded the evidence certainty (quality). We identified eight eligible studies in 10 cohorts involving 343 participants. Risk of bias was moderate or high. Elevated protease activity may be associated with less wound healing (standardized mean difference [SMD]: -0.41, 95% CI -0.72 to -0.11; nine cohorts); and elevated protease inhibitor activity with more healing (SMD: 0.37, 95% CI 0.06-0.68; five cohorts), this is low certainty evidence. Increased protease: inhibitor ratios may be associated with less healing (SMD -0.47, 95% CI -0.94 to -0.01; four cohorts), but this evidence is of very low certainty. Heterogeneity in protease activity was unexplained by prespecified subgroup analyses for wound type or protease activity status, but partially explained by protease class. Posthoc analysis suggested elevated levels of a particular protease, MMP-1, may be associated with more healing and other proteases with less healing. This is low/very low certainty evidence. Limitations were small included studies at moderate or high risk of bias, and the use of posthoc analyses. Elevated protease activity and protease: inhibitor ratios may be associated with less healing, and elevated inhibitor levels with more healing. There may be important differences between MMP-1 and other proteases. High quality research is needed to explore these new findings further.

Negative pressure wound therapy for surgical wounds healing by primary closure.

BACKGROUND: Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). Existing evidence for the effectiveness of NPWT on postoperative wounds healing by primary closure remains uncertain. OBJECTIVES: To assess the effects of NPWT for preventing SSI in wounds healing through primary closure, and to assess the cost-effectiveness of NPWT in wounds healing through primary closure. SEARCH METHODS: In June 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries and references of included studies, systematic reviews and health technology reports. There were no restrictions on language, publication date or study setting. SELECTION CRITERIA: We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another type of NPWT. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, assessment using the Cochrane 'Risk of bias' tool, and quality assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: In this third update, we added 15 new randomised controlled trials (RCTs) and three new economic studies, resulting in a total of 44 RCTs (7447 included participants) and five economic studies. Studies evaluated NPWT in the context of a wide range of surgeries including orthopaedic, obstetric, vascular and general procedures. Economic studies assessed NPWT in orthopaedic, obstetric and general surgical settings. All studies compared NPWT with standard dressings. Most studies had unclear or high risk of bias for at least one key domain. Primary outcomes Four studies (2107 participants) reported mortality. There is low-certainty evidence (downgraded twice for imprecision) showing no clear difference in the risk of death after surgery for people treated with NPWT (2.3%) compared with standard dressings (2.7%) (risk ratio (RR) 0.86; 95% confidence interval (CI) 0.50 to 1.47; I2 = 0%). Thirty-nine studies reported SSI; 31 of these (6204 participants), were included in meta-analysis. There is moderate-certainty evidence (downgraded once for risk of bias) that NPWT probably results in fewer SSI (8.8% of participants) than treatment with standard dressings (13.0% of participants) after surgery; RR 0.66 (95% CI 0.55 to 0.80 ; I2 = 23%). Eighteen studies reported dehiscence; 14 of these (3809 participants) were included in meta-analysis. There is low-certainty evidence (downgraded once for risk of bias and once for imprecision) showing no clear difference in the risk of dehiscence after surgery for NPWT (5.3% of participants) compared with standard dressings (6.2% of participants) (RR 0.88, 95% CI 0.69 to 1.13; I2 = 0%). Secondary outcomes There is low-certainty evidence showing no clear difference between NPWT and standard treatment for the outcomes of reoperation and incidence of seroma. For reoperation, the RR was 1.04 (95% CI 0.78 to 1.41; I2 = 13%; 12 trials; 3523 participants); for seroma, the RR was 0.72 (95% CI 0.50 to 1.05; I2 = 0%; seven trials; 729 participants). The effect of NPWT on occurrence of haematoma or skin blisters is uncertain (very low-certainty evidence); for haematoma, the RR was 0.67 (95% CI 0.28 to 1.59; I2 = 0%; nine trials; 1202 participants) and for blisters the RR was 2.64 (95% CI 0.65 to 10.68; I2 = 69%; seven trials; 796 participants). The overall effect of NPWT on pain is uncertain (very low-certainty evidence from seven trials (2218 participants) which reported disparate measures of pain); but moderate-certainty evidence suggests there is probably little difference between the groups in pain after three or six months following surgery for lower limb fracture (one trial, 1549 participants). There is also moderate-certainty evidence for women undergoing caesarean sections (one trial, 876 participants) and people having surgery for lower limb fractures (one trial, 1549 participants) that there is probably little difference in quality of life scores at 30 days or 3 or 6 months, respectively. Cost-effectiveness Five economic studies, based wholly or partially on trials included in our review, assessed the cost-effectiveness of NPWT compared with standard care. They considered NPWT in four indications: caesarean sections in obese women; surgery for lower limb fracture; knee/hip arthroplasty and coronary artery bypass graft surgery. They calculated quality-adjusted life-years for treatment groups and produced estimates of the treatments' relative cost-effectiveness. The reporting quality was good but the grade of the evidence varied from moderate to very low. There is moderate-certainty evidence that NPWT in surgery for lower limb fracture was not cost-effective at any threshold of willingness-to-pay and that NPWT is probably cost-effective in obese women undergoing caesarean section. Other studies found low or very low-certainty evidence indicating that NPWT may be cost-effective for the indications assessed. AUTHORS' CONCLUSIONS: People experiencing primary wound closure of their surgical wound and treated prophylactically with NPWT following surgery probably experience fewer SSI than people treated with standard dressings (moderate-certainty evidence). There is no clear difference in number of deaths or wound dehiscence between people treated with NPWT and standard dressings (low-certainty evidence). There are also no clear differences in secondary outcomes where all evidence was low or very low-certainty. In caesarean section in obese women and surgery for lower limb fracture, there is probably little difference in quality of life scores (moderate-certainty evidence). Most evidence on pain is very low-certainty, but there is probably no difference in pain between NPWT and standard dressings after surgery for lower limb fracture (moderate-certainty evidence). Assessments of cost-effectiveness of NPWT produced differing results in different indications. There is a large number of ongoing studies, the results of which may change the findings of this review. Decisions about use of NPWT should take into account surgical indication and setting and consider evidence for all outcomes.

Negative pressure wound therapy for surgical wounds healing by primary closure.

BACKGROUND: Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). Existing evidence for the effectiveness of NPWT on postoperative wounds healing by primary closure remains uncertain. OBJECTIVES: To assess the effects of NPWT for preventing SSI in wounds healing through primary closure, and to assess the cost-effectiveness of NPWT in wounds healing through primary closure. SEARCH METHODS: In June 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries and references of included studies, systematic reviews and health technology reports. There were no restrictions on language, publication date or study setting. SELECTION CRITERIA: We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another type of NPWT. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, assessment using the Cochrane 'Risk of bias' tool, and quality assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: In this third update, we added 15 new randomised controlled trials (RCTs) and three new economic studies, resulting in a total of 44 RCTs (7447 included participants) and five economic studies. Studies evaluated NPWT in the context of a wide range of surgeries including orthopaedic, obstetric, vascular and general procedures. Economic studies assessed NPWT in orthopaedic, obstetric and general surgical settings. All studies compared NPWT with standard dressings. Most studies had unclear or high risk of bias for at least one key domain. Primary outcomes Four studies (2107 participants) reported mortality. There is low-certainty evidence (downgraded twice for imprecision) showing no clear difference in the risk of death after surgery for people treated with NPWT (2.3%) compared with standard dressings (2.7%) (risk ratio (RR) 0.86; 95% confidence interval (CI) 0.50 to 1.47; I2 = 0%). Thirty-nine studies reported SSI; 31 of these (6204 participants), were included in meta-analysis. There is moderate-certainty evidence (downgraded once for risk of bias) that NPWT probably results in fewer SSI (8.8% of participants) than treatment with standard dressings (13.0% of participants) after surgery; RR 0.66 (95% CI 0.55 to 0.80 ; I2 = 23%). Eighteen studies reported dehiscence; 14 of these (3809 participants) were included in meta-analysis. There is low-certainty evidence (downgraded once for risk of bias and once for imprecision) showing no clear difference in the risk of dehiscence after surgery for NPWT (5.3% of participants) compared with standard dressings (6.2% of participants) (RR 0.88, 95% CI 0.69 to 1.13; I2 = 0%). Secondary outcomes There is low-certainty evidence showing no clear difference between NPWT and standard treatment for the outcomes of reoperation and incidence of seroma. For reoperation, the RR was 1.04 (95% CI 0.78 to 1.41; I2 = 13%; 12 trials; 3523 participants); for seroma, the RR was 0.72 (95% CI 0.50 to 1.05; I2 = 0%; seven trials; 729 participants). The effect of NPWT on occurrence of haematoma or skin blisters is uncertain (very low-certainty evidence); for haematoma, the RR was 0.67 (95% CI 0.28 to 1.59; I2 = 0%; nine trials; 1202 participants) and for blisters the RR was 2.64 (95% CI 0.65 to 10.68; I2 = 69%; seven trials; 796 participants). The overall effect of NPWT on pain is uncertain (very low-certainty evidence from seven trials (2218 participants) which reported disparate measures of pain); but moderate-certainty evidence suggests there is probably little difference between the groups in pain after three or six months following surgery for lower limb fracture (one trial, 1549 participants). There is also moderate-certainty evidence for women undergoing caesarean sections (one trial, 876 participants) and people having surgery for lower limb fractures (one trial, 1549 participants) that there is probably little difference in quality of life scores at 30 days or 3 or 6 months, respectively. Cost-effectiveness Five economic studies, based wholly or partially on trials included in our review, assessed the cost-effectiveness of NPWT compared with standard care. They considered NPWT in four indications: caesarean sections in obese women; surgery for lower limb fracture; knee/hip arthroplasty and coronary artery bypass graft surgery. They calculated quality-adjusted life-years for treatment groups and produced estimates of the treatments' relative cost-effectiveness. The reporting quality was good but the grade of the evidence varied from moderate to very low. There is moderate-certainty evidence that NPWT in surgery for lower limb fracture was not cost-effective at any threshold of willingness-to-pay and that NPWT is probably cost-effective in obese women undergoing caesarean section. Other studies found low or very low-certainty evidence indicating that NPWT may be cost-effective for the indications assessed. AUTHORS' CONCLUSIONS: People experiencing primary wound closure of their surgical wound and treated prophylactically with NPWT following surgery probably experience fewer SSI than people treated with standard dressings (moderate-certainty evidence). There is no clear difference in number of deaths or wound dehiscence between people treated with NPWT and standard dressings (low-certainty evidence). There are also no clear differences in secondary outcomes where all evidence was low or very low-certainty. In caesarean section in obese women and surgery for lower limb fracture, there is probably little difference in quality of life scores (moderate-certainty evidence). Most evidence on pain is very low-certainty, but there is probably no difference in pain between NPWT and standard dressings after surgery for lower limb fracture (moderate-certainty evidence). Assessments of cost-effectiveness of NPWT produced differing results in different indications. There is a large number of ongoing studies, the results of which may change the findings of this review. Decisions about use of NPWT should take into account surgical indication and setting and consider evidence for all outcomes.

Negative pressure wound therapy for surgical wounds healing by primary closure.

BACKGROUND: Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). While existing evidence for the effectiveness of NPWT remains uncertain, new trials necessitated an updated review of the evidence for the effects of NPWT on postoperative wounds healing by primary closure. OBJECTIVES: To assess the effects of negative pressure wound therapy for preventing surgical site infection in wounds healing through primary closure. SEARCH METHODS: We searched the Cochrane Wounds Specialised Register, CENTRAL, Ovid MEDLINE (including In-Process & Other Non-Indexed Citations), Ovid Embase, and EBSCO CINAHL Plus in February 2018. We also searched clinical trials registries for ongoing and unpublished studies, and checked reference lists of relevant included studies as well as reviews, meta-analyses, and health technology reports to identify additional studies. There were no restrictions on language, publication date, or setting. SELECTION CRITERIA: We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another type of NPWT. DATA COLLECTION AND ANALYSIS: Four review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and quality assessment according to GRADE methodology. MAIN RESULTS: In this second update we added 25 intervention trials, resulting in a total of 30 intervention trials (2957 participants), and two economic studies nested in trials. Surgeries included abdominal and colorectal (n = 5); caesarean section (n = 5); knee or hip arthroplasties (n = 5); groin surgery (n = 5); fractures (n = 5); laparotomy (n = 1); vascular surgery (n = 1); sternotomy (n = 1); breast reduction mammoplasty (n = 1); and mixed (n = 1). In three key domains four studies were at low risk of bias; six studies were at high risk of bias; and 20 studies were at unclear risk of bias. We judged the evidence to be of low or very low certainty for all outcomes, downgrading the level of the evidence on the basis of risk of bias and imprecision.Primary outcomesThree studies reported mortality (416 participants; follow-up 30 to 90 days or unspecified). It is uncertain whether NPWT has an impact on risk of death compared with standard dressings (risk ratio (RR) 0.63, 95% confidence interval (CI) 0.25 to 1.56; very low-certainty evidence, downgraded once for serious risk of bias and twice for very serious imprecision).Twenty-five studies reported on SSI. The evidence from 23 studies (2533 participants; 2547 wounds; follow-up 30 days to 12 months or unspecified) showed that NPWT may reduce the rate of SSIs (RR 0.67, 95% CI 0.53 to 0.85; low-certainty evidence, downgraded twice for very serious risk of bias).Fourteen studies reported dehiscence. We combined results from 12 studies (1507 wounds; 1475 participants; follow-up 30 days to an average of 113 days or unspecified) that compared NPWT with standard dressings. It is uncertain whether NPWT reduces the risk of wound dehiscence compared with standard dressings (RR 0.80, 95% CI 0.55 to 1.18; very low-certainty evidence, downgraded twice for very serious risk of bias and once for serious imprecision).Secondary outcomesWe are uncertain whether NPWT increases or decreases reoperation rates when compared with a standard dressing (RR 1.09, 95% CI 0.73 to 1.63; 6 trials; 1021 participants; very low-certainty evidence, downgraded for very serious risk of bias and serious imprecision) or if there is any clinical benefit associated with NPWT for reducing wound-related readmission to hospital within 30 days (RR 0.86, 95% CI 0.47 to 1.57; 7 studies; 1271 participants; very low-certainty evidence, downgraded for very serious risk of bias and serious imprecision). It is also uncertain whether NPWT reduces incidence of seroma compared with standard dressings (RR 0.67, 95% CI 0.45 to 1.00; 6 studies; 568 participants; very low-certainty evidence, downgraded twice for very serious risk of bias and once for serious imprecision). It is uncertain if NPWT reduces or increases the risk of haematoma when compared with a standard dressing (RR 1.05, 95% CI 0.32 to 3.42; 6 trials; 831 participants; very low-certainty evidence, downgraded twice for very serious risk of bias and twice for very serious imprecision. It is uncertain if there is a higher risk of developing blisters when NPWT is compared with a standard dressing (RR 6.64, 95% CI 3.16 to 13.95; 6 studies; 597 participants; very low-certainty evidence, downgraded twice for very serious risk of bias and twice for very serious imprecision).Quality of life was not reported separately by group but was used in two economic evaluations to calculate quality-adjusted life years (QALYs). There was no clear difference in incremental QALYs for NPWT relative to standard dressing when results from the two trials were combined (mean difference 0.00, 95% CI -0.00 to 0.00; moderate-certainty evidence).One trial concluded that NPWT may be more cost-effective than standard care, estimating an incremental cost-effectiveness ratio (ICER) value of GBP 20.65 per QALY gained. A second cost-effectiveness study estimated that when compared with standard dressings NPWT was cost saving and improved QALYs. We rated the overall quality of the reports as very good; we did not grade the evidence beyond this as it was based on modelling assumptions. AUTHORS' CONCLUSIONS: Despite the addition of 25 trials, results are consistent with our earlier review, with the evidence judged to be of low or very low certainty for all outcomes. Consequently, uncertainty remains about whether NPWT compared with a standard dressing reduces or increases the incidence of important outcomes such as mortality, dehiscence, seroma, or if it increases costs. Given the cost and widespread use of NPWT for SSI prophylaxis, there is an urgent need for larger, well-designed and well-conducted trials to evaluate the effects of newer NPWT products designed for use on clean, closed surgical incisions. Such trials should initially focus on wounds that may be difficult to heal, such as sternal wounds or incisions on obese patients.

Dressings and topical agents for treating venous leg ulcers.

BACKGROUND: Venous leg ulcers are open skin wounds on the lower leg which can be slow to heal, and are both painful and costly. The point prevalence of open venous leg ulcers in the UK is about 3 cases per 10,000 people, and many people experience recurrent episodes of prolonged ulceration. First-line treatment for venous leg ulcers is compression therapy, but a wide range of dressings and topical treatments are also used. This diversity of treatments makes evidence-based decision-making challenging, and a clear and current overview of all the evidence is required. This review is a network meta-analysis (NMA) which assesses the probability of complete ulcer healing associated with alternative dressings and topical agents. OBJECTIVES: To assess the effects of (1) dressings and (2) topical agents for healing venous leg ulcers in any care setting and to rank treatments in order of effectiveness, with assessment of uncertainty and evidence quality. SEARCH METHODS: In March 2017 we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also scanned reference lists of relevant included studies as well as reviews, meta-analyses, guidelines and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. We updated this search in March 2018; as a result several studies are awaiting classification. SELECTION CRITERIA: We included published or unpublished randomised controlled trials (RCTs) that enrolled adults with venous leg ulcers and compared the effects of at least one of the following interventions with any other intervention in the treatment of venous leg ulcers: any dressing, or any topical agent applied directly to an open venous leg ulcer and left in situ. We excluded from this review dressings attached to external devices such as negative pressure wound therapies, skin grafts, growth factors and other biological agents, larval therapy and treatments such as laser, heat or ultrasound. Studies were required to report complete wound healing to be eligible. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection, 'Risk of bias' assessment and data extraction. We conducted this NMA using frequentist meta-regression methods for the efficacy outcome; the probability of complete healing. We assumed that treatment effects were similar within dressings classes (e.g. hydrocolloid, foam). We present estimates of effect with their 95% confidence intervals (CIs) for individual treatments focusing on comparisons with widely used dressing classes, and we report ranking probabilities for each intervention (probability of being the best, second best, etc treatment). We assessed the certainty (quality) of the body of evidence using GRADE for each network comparison and for the network as whole. MAIN RESULTS: We included 78 RCTs (7014 participants) in this review. Of these, 59 studies (5156 participants, 25 different interventions) were included in the NMA; resulting in 40 direct contrasts which informed 300 mixed-treatment contrasts.The evidence for the network as a whole was of low certainty. This judgement was based on the sparsity of the network leading to imprecision and the general high risk of bias in the included studies. Sensitivity analyses also demonstrated instability in key aspects of the network and results are reported for the extended sensitivity analysis. Evidence for individual contrasts was mainly judged to be low or very low certainty.The uncertainty was perpetuated when the results were considered by ranking the treatments in terms of the probability that they were the most effective for ulcer healing, with many treatments having similar, low, probabilities of being the best treatment. The two most highly-ranked treatments both had more than 50% probability of being the best (sucralfate and silver dressings). However, the data for sucralfate was from one small study, which means that this finding should be interpreted with caution. When exploring the data for silver and sucralfate compared with widely-used dressing classes, there was some evidence that silver dressings may increase the probability of venous leg ulcer healing, compared with nonadherent dressings: RR 2.43, 95% CI 1.58 to 3.74 (moderate-certainty evidence in the context of a low-certainty network). For all other combinations of these five interventions it was unclear whether the intervention increased the probability of healing; in each case this was low- or very low-certainty evidence as a consequence of one or more of imprecision, risk of bias and inconsistency. AUTHORS' CONCLUSIONS: More research is needed to determine whether particular dressings or topical agents improve the probability of healing of venous leg ulcers. However, the NMA is uninformative regarding which interventions might best be included in a large trial, largely because of the low certainty of the whole network and of individual comparisons.The results of this NMA focus exclusively on complete healing; whilst this is of key importance to people living with venous leg ulcers, clinicians may wish to take into account other patient-important outcomes and factors such as patient preference and cost.

Negative pressure wound therapy for open traumatic wounds.

BACKGROUND: Traumatic wounds (wounds caused by injury) range from abrasions and minor skin incisions or tears, to wounds with extensive tissue damage or loss as well as damage to bone and internal organs. Two key types of traumatic wounds considered in this review are those that damage soft tissue only and those that involve a broken bone, that is, open fractures. In some cases these wounds are left open and negative pressure wound therapy (NPWT) is used as a treatment. This medical device involves the application of a wound dressing through which negative pressure is applied and tissue fluid drawn away from the area. The treatment aims to support wound management, to prepare wounds for further surgery, to reduce the risk of infection and potentially to reduce time to healing (with or without surgical intervention). There are no systematic reviews assessing the effectiveness of NPWT for traumatic wounds. OBJECTIVES: To assess the effects of NPWT for treating open traumatic wounds in people managed in any care setting. SEARCH METHODS: In June 2018 we searched the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE (including In-Process & Other Non-Indexed Citations), Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: Published and unpublished randomised controlled trials that used NPWT for open traumatic wounds involving either open fractures or soft tissue wounds. Wound healing, wound infection and adverse events were our primary outcomes. DATA COLLECTION AND ANALYSIS: Two review authors independently selected eligible studies, extracted data, carried out a 'Risk of bias' assessment and rated the certainty of the evidence. Data were presented and analysed separately for open fracture wounds and other open traumatic wounds (not involving a broken bone). MAIN RESULTS: Seven RCTs (1377 participants recruited) met the inclusion criteria of this review. Study sample sizes ranged from 40 to 586 participants. One study had three arms, which were all included in the review. Six studies compared NPWT at 125 mmHg with standard care: one of these studies did not report any relevant outcome data. One further study compared NPWT at 75 mmHg with standard care and NPWT 125mmHg with NPWT 75 mmHg.Open fracture wounds (four studies all comparing NPWT 125 mmHg with standard care)One study (460 participants) comparing NPWT 125 mmHg with standard care reported the proportions of wounds healed in each arm. At six weeks there was no clear difference between groups in the number of participants with a healed, open fracture wound: risk ratio (RR) 1.01 (95% confidence interval (CI) 0.81 to 1.27); moderate-certainty evidence, downgraded for imprecision.We pooled data on wound infection from four studies (596 participants). Follow-up varied between studies but was approximately 30 days. On average, it is uncertain whether NPWT at 125 mmHg reduces the risk of wound infection compared with standard care (RR 0.48, 95% CI 0.20 to 1.13; I2 = 56%); very low-certainty evidence downgraded for risk of bias, inconsistency and imprecision.Data from one study shows that there is probably no clear difference in health-related quality of life between participants treated with NPWT 125 mmHg and those treated with standard wound care (EQ-5D utility scores mean difference (MD) -0.01, 95% CI -0.08 to 0.06; 364 participants, moderate-certainty evidence; physical component summary score of the short-form 12 instrument MD -0.50, 95% CI -4.08 to 3.08; 329 participants; low-certainty evidence downgraded for imprecision).Moderate-certainty evidence from one trial (460 participants) suggests that NPWT is unlikely to be a cost-effective treatment for open fractures in the UK. On average, NPWT was more costly and conferred few additional quality-adjusted life years (QALYs) when compared with standard care. The incremental cost-effectiveness ratio was GBP 267,910 and NPWT was shown to be unlikely to be cost effective at a range of cost-per-QALYs thresholds. We downgraded the certainty of the evidence for imprecision.Other open traumatic wounds (two studies, one comparing NPWT 125 mmHg with standard care and a three-arm study comparing NPWT 125 mmHg, NPWT 75 mmHg and standard care)Pooled data from two studies (509 participants) suggests no clear difference in risk of wound infection between open traumatic wounds treated with NPWT at 125 mmHg or standard care (RR 0.61, 95% CI 0.31 to 1.18); low-certainty evidence downgraded for risk of bias and imprecision.One trial with 463 participants compared NPWT at 75 mmHg with standard care and with NPWT at 125 mmHg. Data on wound infection were reported for each comparison. It is uncertain if there is a difference in risk of wound infection between NPWT 75 mmHg and standard care (RR 0.44, 95% CI 0.17 to 1.10; 463 participants) and uncertain if there is a difference in risk of wound infection between NPWT 75 mmHg and 125 mmHg (RR 1.04, 95% CI 0.31 to 3.51; 251 participants. We downgraded the certainty of the evidence for risk of bias and imprecision. AUTHORS' CONCLUSIONS: There is moderate-certainty evidence for no clear difference between NPWT and standard care on the proportion of wounds healed at six weeks for open fracture wounds. There is moderate-certainty evidence that NPWT is not a cost-effective treatment for open fracture wounds. Moderate-certainty evidence means that the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. It is uncertain whether there is a difference in risk of wound infection, adverse events, time to closure or coverage surgery, pain or health-related quality of life between NPWT and standard care for any type of open traumatic wound.

Protease activity as a prognostic factor for wound healing in venous leg ulcers.

BACKGROUND: Venous leg ulcers (VLUs) are a common type of complex wound that have a negative impact on people's lives and incur high costs for health services and society. It has been suggested that prolonged high levels of protease activity in the later stages of the healing of chronic wounds may be associated with delayed healing. Protease modulating treatments have been developed which seek to modulate protease activity and thereby promote healing in chronic wounds. OBJECTIVES: To determine whether protease activity is an independent prognostic factor for the healing of venous leg ulcers. SEARCH METHODS: In February 2018, we searched the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid Embase and CINAHL. SELECTION CRITERIA: We included prospective and retrospective longitudinal studies with any follow-up period that recruited people with VLUs and investigated whether protease activity in wound fluid was associated with future healing of VLUs. We included randomised controlled trials (RCTs) analysed as cohort studies, provided interventions were taken into account in the analysis, and case-control studies if there were no available cohort studies. We also included prediction model studies provided they reported separately associations of individual prognostic factors (protease activity) with healing. Studies of any type of protease or combination of proteases were eligible, including proteases from bacteria, and the prognostic factor could be examined as a continuous or categorical variable; any cut-off point was permitted. The primary outcomes were time to healing (survival analysis) and the proportion of people with ulcers completely healed; the secondary outcome was change in ulcer size/rate of wound closure. We extracted unadjusted (simple) and adjusted (multivariable) associations between the prognostic factor and healing. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion at each stage, and undertook data extraction, assessment of risk of bias and GRADE assessment. We collected association statistics where available. No study reported adjusted analyses: instead we collected unadjusted results or calculated association measures from raw data. We calculated risk ratios when both outcome and prognostic factor were dichotomous variables. When the prognostic factor was reported as continuous data and healing outcomes were dichotomous, we either performed regression analysis or analysed the impact of healing on protease levels, analysing as the standardised mean difference. When both prognostic factor and outcome were continuous data, we reported correlation coefficients or calculated them from individual participant data.We displayed all results on forest plots to give an overall visual representation. We planned to conduct meta-analyses where this was appropriate, otherwise we summarised narratively. MAIN RESULTS: We included 19 studies comprising 21 cohorts involving 646 participants. Only 11 studies (13 cohorts, 522 participants) had data available for analysis. Of these, five were prospective cohort studies, four were RCTs and two had a type of case-control design. Follow-up time ranged from four to 36 weeks. Studies covered 10 different matrix metalloproteases (MMPs) and two serine proteases (human neutrophil elastase and urokinase-type plasminogen activators). Two studies recorded complete healing as an outcome; other studies recorded partial healing measures. There was clinical and methodological heterogeneity across studies; for example, in the definition of healing, the type of protease and its measurement, the distribution of active and bound protease species, the types of treatment and the reporting of results. Therefore, meta-analysis was not performed. No study had conducted multivariable analyses and all included evidence was of very low certainty because of the lack of adjustment for confounders, the high risk of bias for all studies except one, imprecision around the measures of association and inconsistency in the direction of association. Collectively the research indicated complete uncertainty as to the association between protease activity and VLU healing. AUTHORS' CONCLUSIONS: This review identified very low validity evidence regarding any association between protease activity and VLU healing and there is complete uncertainty regarding the relationship. The review offers information for both future research and systematic review methodology.