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BACKGROUND: Exact quantification of volumetric changes of the extremities is difficult and often error-prone. The aim of this study was to establish a standardized method based on 3-dimensional (3D) scans. Furthermore, this study tests the method in terms of reproducibility and evaluates volume changes after surgical therapy in patients suffering from lymphedema on the lower extremity. METHODS: 3D scans of the lower limb were performed with a mobile 3D scanner; "repeatability" and "interobserver reliability" of digital volumetry were tested. Furthermore, the method was applied on 31 patients suffering from chronic lymphedema. RESULTS: Calculations of repeatability of the volume based on 20 3D scans of the same lower leg showed a mean volume of 2.488 ± 0.011 liters (range: 2.470-2.510). The mean volume of the different examiners did not differ significantly (F(2,18) = 1.579, P = 0.233). The paired t-test showed a significant mean volume decrease of 375 mL (95% confidence interval = 245/505 mL) between pretreatment and post-treatment (t (30) = 5.892, P < 0.001). CONCLUSIONS: 3D volumetry is a noninvasive, easy, and quick method to assess volume changes of the lower leg. Other than the low costs, it is reproducible and precise and therefore ideal for evolution of therapy in lymphedema.
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Imagenología Tridimensional , Extremidad Inferior , Linfedema , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Humanos , Reproducibilidad de los Resultados , Linfedema/diagnóstico por imagen , Linfedema/terapia , Femenino , Persona de Mediana Edad , Masculino , Resultado del Tratamiento , Anciano , Adulto , Enfermedad CrónicaRESUMEN
Background: Complex decongestive therapy (CDT) is the standard and basic therapy for lymphedema. The central component of CDT is manual lymphatic drainage (MLD). In addition to CDT, other measures such as intermittent pneumatic compression therapy (IPCT) (active compression machine therapy) are available. In this prospective research study, the objective and subjective effects of MLD and IPCT on lymphedema of the lower extremity were investigated and both therapies were directly compared. Furthermore, the patients' body mass index (BMI) and stage of lymphedema were tested for their effect on the respective therapy. Methods: Patients participating in the study received both therapies (MLD and IPCT) on the same lymphedema-affected limb at an interval of two days. The objective volumetric therapy effect was measured by the digital volume measurement of the affected limb. The subjective effects of the therapies were measured using two specially designed questionnaires. Results: A total of 40 patients were included in the study. There was no significant difference in the volume differences between the interventions, BMI categories, lymphedema, or treatment order regarding the immediate and two-day effect. Conclusions: No significant difference was found in the subjective or objective therapy efficacy of the two methods. Intermittent pneumatic compression therapy is considered a comparable therapeutic procedure when properly indicated.
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CONTEXT: Global sales of compression garments have risen sharply in recent years. Due to the availability of a wide range of compression garments, this study aims to evaluate the effect of two types of compression garments and kinesio tape on edema formation and tissue perfusion in the lower extremities. Over-the-counter compression knee stockings and kinesio tape were compared with a prototype of high-end compression stockings that combine kinesio tape and a common knee bandage. The high-end compression stockings were designed by Cube with the aim of combining the positive effects of kinesio tape and compression garments on edema formation and tissue perfusion. DESIGN: Clinical cross-over study. METHODS: Before and after a 6-hour compression period, the knee regions on both, the treated and non-treated leg, of participants were examined using a 3-D scan to detect changes in volume. Also measured were local temperature (°C), oxygen saturation (SpO2), perfusion index (Pi), blood pressure (mmHg), compression pressure (mmHg), range of motion, body-mass-index (BMI) and limb-circumference (cm). Two different types of compression garments were examined: a novel high-end compression stocking (A) and a common compression stocking (B). In addition, kinesio tape was compared to compression garments (C). After each experimental day, a one-day break was taken to prevent an unwanted overlay effect. Male and female participants between the ages of 18 and 60 were randomly selected. RESULTS: The high-end compression garment (A) showed a statistically significant (Pâ=â0.009) reduction of edema intraindividually. Comparing the three treatment groups, compression (A) lead to a reduction of edema. However, the reduction was not statistically significant (Pâ=â0.585). The compression garment B and kinesio tape showed an increase in edema in the lower limb. There was a positive correlation between the highest compression pressure (A: 9.8 mmHg) and volume decrease over the period of 6 hours. Lighter compression (B: 8.2 mmHg) led to an increase in leg volume after compression application over 6 hours. There was no significant difference in tissue oxygen saturation with the two types of compression and kinesio tape. The tissue temperature below the compression garment was highest in the compression group A. Nevertheless, we could not demonstrate a statistically significant correlation between tissue temperature and volume difference.The range in motion of the lower limb decreased after 6 hours with both compression A and B and with kinesio tape. CONCLUSION: The novel bandage showed a statistically significant reduction in edema when compared intraindividually, but no statistically significant advantage was found when compared with the other compression garment B and kinesio tape.Despite the widespread use of kinesio tape, we did not find any improvement in the range of motion, edema prevention and circulation in the lower limb after application of kinesio tape.
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Cinta Atlética , Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Estudios Cruzados , Edema/prevención & control , Medias de Compresión , Extremidad Inferior , Vestuario , PerfusiónRESUMEN
Key Clinical Message: Early and complete surgical resection is the most important therapeutic and diagnostic measure. Adjuvant radiation is suggested for malign phyllode tumors, phyllode tumors larger than 10 cm or those with a low distance to the resection margins. Abstract: Phyllodes tumors are rare fibroepithelial tumors of the breast. Histologically, they are usually classified as benign, borderline or malignant, though these classifications do not necessarily reflect the clinical course of the disease. These tumors may stay undetected for years, or show sudden and rapid progression. There is currently no consistent therapy recommendation based upon histological findings, the localization of the tumor and/or whether it is recurrent. Using the examples of three patients, we show how courses and therapy may differ widely, and discuss this in the context of the current state of the literature.
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BACKGROUND: Complication rates of up to 46 percent are reported following pressure sore surgery. Pressure sore patients often exhibit ineffective postoperative wound healing despite tension-free flap coverage, necessitating surgical revision and prolonged hospitalization. Rather than pressure sore recurrence, such impaired healing reflects a failed progress through the physiologic stages of the normal wound-healing cascade. The principal objective of the study reported here was to elucidate potentially modifiable inherent variables that predict predisposition to impaired healing and to provide a tool for identifying cases at risk for complicated early postoperative recovery following pressure sore reconstruction. METHODS: A retrospective chart review of late-stage (stage 3 or higher) sacral and ischial pressure sore patients who underwent flap reconstruction from 2014 to 2019 was performed. A multivariable logistic regression model was used to identify key patient and operative factors predictive of impaired healing. Furthermore, the Assessment Score to Predict Pressure Sore Impaired Healing (A-PePSI) was established based on the identified risk factors. RESULTS: In a cohort of 121 patients, 36 percent exhibited impaired healing. Of these, 34 patients suffered from dehiscences, necessitating surgical revision. Statistically significant risk factors comprising late recurrence (OR, 3.8), immobility (OR, 12.4), greater surface (>5 cm diameter; OR, 7.3), and inhibited thrombocytes (aspirin monotherapy; OR, 5.7) were combined to formulate a prognostic scoring system (A-PePSI LIGhT). CONCLUSIONS: The A-PePSI LIGhT score serves as a prognostic instrument for assessing individual risk for impaired healing in pressure sore patients. Preoperative risk stratification supports rational decision-making regarding operative candidacy, allows evidence-based patient counseling, and supports the implementation of individualized treatment protocols. . CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.
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Plaquetas/fisiología , Complicaciones Posoperatorias/epidemiología , Úlcera por Presión/fisiopatología , Úlcera por Presión/cirugía , Cicatrización de Heridas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Recurrencia , Reoperación , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Adulto JovenRESUMEN
OBJECTIVE: Chronic primary or secondary lymphedema has huge effects on patients' quality of life (QOL) because of the associated swelling and pain, decreased range of motion, and depression and anxiety and generally requires numerous adaptations. Many studies have shown a positive objective effect of lymphovenous anastomoses (LVAs) on chronic lymphedema. In the present study, we assessed the effect of LVAs on QOL in patients with primary or secondary lymphedema of the lower extremity at 6 months after surgery and examined the correlation between changes in the QOL and volumetric measurements. METHODS: Only patients with either primary or secondary lymphedema of the lower extremity who had undergone LVAs were included in the present study. To assess QOL, a specially designed questionnaire based on the Lymphedema Quality of Life Inventory was used to evaluate the subjective therapeutic results from the patients' perspective. Objective therapy success was assessed using three-dimensional volumetric measurements of the lower leg. The measuring points, for both the subjective and the objective measurements, were the day before and 6 months after therapy. RESULTS: The mean change in volume at 6 months after LVA was -6.5% ± 5.6% (P < .001). Significantly better QOL in terms of physical (37.6% ± 25.2%) and psychosocial (27.0% ± 43.0%) domains and practical restrictions (22.3% ± 24.8%) was found (P < .001 for all). No correlation was found between QOL improvement and volume decrease (P > .05). CONCLUSIONS: For patients with lymphedema of the lower extremity, LVAs can lead to a significant volumetric decrease and QOL improvement at 6 months after treatment with no demonstrable relationship between QOL improvement and volume reduction.
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Extremidad Inferior/cirugía , Linfedema/cirugía , Calidad de Vida , Encuestas y Cuestionarios , Adulto , Anciano , Anastomosis Quirúrgica , Enfermedad Crónica , Costo de Enfermedad , Femenino , Humanos , Extremidad Inferior/patología , Extremidad Inferior/fisiopatología , Linfedema/patología , Linfedema/fisiopatología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Tiempo , Resultado del TratamientoRESUMEN
The superficial circumflex iliac artery perforator (SCIP) flap is a well-documented, thin, free tissue flap with a minimal donor site morbidity, and has the potential to become the new method for resurfacing moderate-size skin defects. The aim of this study is to describe an easy, reliable, systematic, and standardized approach for preoperative SCIP flap design and perforator characterization, using color-coded duplex sonography (CCDS). A list of customized settings and a straightforward algorithm are presented, which are easily applied by an operator with minimal experience. Specific settings for SCIP flap perforator evaluation were investigated and tested on 12 patients. Deep and superficial superficial circumflex iliac artery (SCIA) branches, along with their corresponding perforators and cutaneous veins, were marked individually with a permanent marker and the anatomy was verified intraoperatively. From this, a simplified procedure for preoperative flap design of the SCIP flap was developed. Branches could be localized and evaluated in all patients. A preoperative structured procedure for ultrasonically guided flap design of the SCIP flap is described. A 100% correlation between the number and emergence points of the branches detected by preoperative CCDS mapping and the intraoperative anatomy was found.
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BACKGROUND: During negative pressure wound therapy (NPWT), open wounds are draped with a nontransparent sponge, making daily wound evaluation impossible. Sometimes, late or undetected bacterial infections and postoperative bleeding result in repetitive surgery, thus prolonging inpatient time. With the introduction of additional fluid instillation (NPWTi), the wound surface is rinsed, and bacteria, proteins and biomarkers are flushed into a collecting canister, which is later discarded. METHODS: The aim of this pilot study was to analyze rinsing fluid samples (0.9% sodium chloride) from the NPWTi device in patients with acute and chronic wounds. In 31 consecutive patients a standardized laboratory analysis was performed to evaluate cellular composition and potassium, phosphate, lactate dehydrooxygenase, pH and total protein levels. RESULTS: While there was an increase in the total cellular amount and the number of polymorphonuclear cells, the number of red blood cells (RBC) decreased after surgery. Potassium and pH showed no significant changes in the first three postoperative days, whereas total protein showed an undulant and partially significant course. CONCLUSION: We were able to quantify cellular metabolites by analyzing the rinsing fluid of NPWTi. We propose the analysis of this material as a novel and potentially promising tool to monitor wound status without removal of the dressing. The establishment of reference values might help to improve the NPWTi therapy.
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Terapia de Presión Negativa para Heridas , Cicatrización de Heridas , Heridas y Lesiones/terapia , Enfermedad Aguda , Enfermedad Crónica , Recuento de Eritrocitos , Femenino , Humanos , Concentración de Iones de Hidrógeno , Instilación de Medicamentos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Potasio/análisis , Proteínas/análisis , Heridas y Lesiones/sangreRESUMEN
BACKGROUND: Thanks to 3D imaging, it is possible to measure the influence of different parameters on breast augmentation. In this study, we compare the effect of different shapes and sizes of breast implants on the topography of the resulting breast. Furthermore, the impact of different breast implants on inter-landmark distances and on changes of the nipple position was assessed. METHODS: This interventional prospective study was carried out on 10 female patients after collecting informed consent. 3D scans of the native and augmented breasts were performed intraoperatively with small, medium, and large sizes of both anatomical and round implants, resulting in a total of n = 130 single breast scans. These scans were analyzed for topographic shift quantification, nipple migration, and inter-landmark distances of the breast. RESULTS: Implant size, but not implant shape leads to significant topographic shifts of the breast (p < 0.001 and p = 0.900, respectively). Both round and anatomical implants lead to a significantly higher volumetric increase in the upper quadrants compared to the lower quadrants (p < 0.001). Nipple migration into the superomedial quadrant was seen in about 90% of augmentations. No evident differences in inter-landmark distances were observed when round and anatomical implants of different sizes were compared. CONCLUSIONS: Implant size rather than shape influences the postoperative aesthetic results. No significant difference in topographic shift was found comparing round and anatomical implants, suggesting that both implant shapes result in comparable aesthetic outcomes.
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PURPOSE: To assess precise topographic changes of the breast, objective documentation and evaluation of pre- and postoperative results are crucial. New technologies for mapping the body using digital, three-dimensional surface measurements have offered novel ways to numerically assess the female breast. Due to the lack of clear demarcation points of the breast contour, the selection of landmarks on the breast is highly dependent on the examiner, and, therefore, is prone to error when conducting before-after comparisons of the same breast. This study describes an alternative to volumetric measurements, focusing on topographic changes of the female breast, based on three-dimensional scans. METHOD: The study was designed as an interventional prospective study of 10 female volunteers who had planned on having aesthetic breast augmentation with anatomical, textured implants. Three dimensional scans of the breasts were performed intraoperatively, first without and then with breast implants. The topographic change was determined as the mean distance between two three-dimensional layers before and after augmentation. This mean distance is defined as the Topographic Shift. RESULTS: The mean implant volume was 283 cc (SD = 68.6 cc, range = 210-395 cc). The mean Topographic Shift was 7.4 mm (SD = 1.9 mm, range = 4.8-10.7 mm). The mean Topographic Shifts per quadrant were: I: 8.0 mm (SD = 3.3 mm); II: 9.2 mm (SD = 3.1 mm); III: 6.9 mm (SD = 3.5 mm); IV: 1.9 mm (SD = 4.3 mm). CONCLUSION: The Topographic Shift, describing the mean distance between two three-dimensional layers (for example before and after a volume changing therapy), is a new approach that can be used for assessing topographic changes of a body area. It was found that anatomical, textured breast implants cause a topographic change, particularly on the upper breast, in quadrant II, the décolleté.
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Implantación de Mama/métodos , Implantes de Mama , Mama/cirugía , Imagenología Tridimensional/métodos , Mamoplastia/métodos , Adulto , Estética , Femenino , Humanos , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
PURPOSE: In this trial, we used a previously developed prototype software to assess aesthetic results after reconstructive surgery for congenital breast asymmetry using automated anthropometry. To prove the consensus between the manual and automatic digital measurements, we evaluated the software by comparing the manual and automatic measurements of 46 breasts. METHODS: Twenty-three patients who underwent reconstructive surgery for congenital breast asymmetry at our institution were examined and underwent 3D surface imaging. Per patient, 14 manual and 14 computer-based anthropometric measurements were obtained according to a standardized protocol. Manual and automatic measurements, as well as the previously proposed Symmetry Index (SI), were compared. RESULTS: The Wilcoxon signed-rank test revealed no significant differences in six of the seven measurements between the automatic and manual assessments. The SI showed robust agreement between the automatic and manual methods. CONCLUSION: The present trial validates our method for digital anthropometry. Despite the discrepancy in one measurement, all remaining measurements, including the SI, showed high agreement between the manual and automatic methods. The proposed data bring us one step closer to the long-term goal of establishing robust instruments to evaluate the results of breast surgery. LEVEL OF EVIDENCE: IV.
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Mama/anatomía & histología , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Antropometría/métodos , Estética , Femenino , Humanos , Mastectomía , Reproducibilidad de los Resultados , Programas InformáticosRESUMEN
BACKGROUND: Breast reconstruction is an important coping tool for patients undergoing a mastectomy. There are numerous surgical techniques in breast reconstruction surgery (BRS). Regardless of the technique used, creating a symmetric outcome is crucial for patients and plastic surgeons. Three-dimensional surface imaging enables surgeons and patients to assess the outcome's symmetry in BRS. To discriminate between autologous and alloplastic techniques, we analyzed both techniques using objective optical computerized symmetry analysis. Software was developed that enables clinicians to assess optical breast symmetry using three-dimensional surface imaging. METHODS: Twenty-seven patients who had undergone autologous (n = 12) or alloplastic (n = 15) BRS received three-dimensional surface imaging. Anthropomorphic data were collected digitally using semiautomatic measurements and automatic measurements. Automatic measurements were taken using the newly developed software. To quantify symmetry, a Symmetry Index is proposed. RESULTS: Statistical analysis revealed that there is no difference in the outcome symmetry between the two groups (t test for independent samples; p = 0.48, two-tailed). CONCLUSION: This study's findings provide a foundation for qualitative symmetry assessment in BRS using automatized digital anthropometry. In the present trial, no difference in the outcomes' optical symmetry was detected between autologous and alloplastic approaches. Level of evidence Level IV. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Neoplasias de la Mama , Mamoplastia , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Estudios de Cohortes , Estética , Humanos , Mastectomía , Estudios Retrospectivos , Medición de Riesgo , Resultado del TratamientoRESUMEN
Background: The influence of pulsed electromagnetic field therapy (PEMFT) on medium-sized vessels as well as capillary microcirculation is well known. Effects on lymphatic vessels, however, are difficult to visualize and have not been investigated to date. One of the operative treatment options in primary and secondary lymphedemas is lymphovenous anastomoses using supermicrosurgery. To prove patency of the anastomosis, the lymphatic flow is visualized by fluorescence using indocyanine green. The aim of this study was to investigate the influence of PEMFT on the lymphatic microcirculation, and compare it with conventional manual lymphatic drainage (MLD) during supermicrosurgery. Methods and Results: Ten patients with lymphedema were included. Indocyanine green was injected before the operation for intraoperative visualization of the lymphatic vessels using a microscope equipped with an integrated near-infrared illumination system (Zeiss). The PEMFT system (Bio-Electro-Magnetic-Energy Regulation [BEMER]) was used as our standard device during a single 2-minute application period (AP) followed by MLD or vice versa. The mean light intensity in the calibration period (CP) was 46.53 ± 24.3 and 33.41 ± 12.92 for PEMFT and MLD, respectively. During the AP, the mean light intensity changed to 45.61 ± 24.40 for PEMFT and 57.05 ± 18.80 during MLD. This change between CP and AP did not differ significantly for the PEMFT application (p = 0.26), but showed an increase in light intensity during MLD (p < 0.001). Conclusion: We found a light intensity enhancement equivalent to a flow increase during MLD of 78.7% ± 45.7% (range 20%-144%) and no significant difference during the PEMFT application. A single period application of PEMFT did not affect the lymphatic flow.
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Vasos Linfáticos , Linfedema , Magnetoterapia , Microcirugia , Campos Electromagnéticos , Humanos , Verde de Indocianina , Vasos Linfáticos/diagnóstico por imagen , Linfedema/terapia , Linfografía , Drenaje Linfático ManualRESUMEN
INTRODUCTION: Multiple symmetric lipomatosis (MSL) (syn.: Launois-Bensaude Syndrome, benign symmetric lipomatosis) is a rare disease of fatty tissue. The pathophysiology of MSL still remains unclear, although several approaches have been described in order to understand it. Beside morphological characteristics and some molecular cell biological approaches, little is known about the histological and immunohistochemical characterization of adipose tissue from patients with MSL. METHODS: From the 45 patients with MSL in our database, 10 were included in the study. Fat tissue samples were collected from affected and unaffected areas. The forearm served as a control area as this area is not affected in MSL. The specimens were analyzed after selected stainings were taken (hematoxylin-eosin = HE, Elastica van Gieson, Ladewig, CD200, CIDEA, myf5, p107, Prdm16, Sca-1, syndecan, UCP1, MAC387, Glut4). RESULTS: In patients suffering from MSL, no macroscopic or microscopic morphological difference could be found between affected and unaffected adipose tissue in HE stainings. The majority of samples showed positivity for UCP1 (9/10 clinically affected tissues, 7/10 clinically unaffected tissues) and CD200. CONCLUSION: Marker profiles support the hypothesis that affected adipose tissue derives from brown or beige adipose tissue rather than from white fat. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
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Tejido Adiposo Beige , Lipomatosis Simétrica Múltiple , Tejido Adiposo , Humanos , Lipomatosis Simétrica Múltiple/cirugíaRESUMEN
AIM OF THE STUDY: Negative pressure wound therapy is thought to improve wound healing by altering capillary perfusion. However, despite many theories, the underlying mechanism of action remains controversial. Recent evidence suggests an increased tissue pressure and a temporary decreased microvascular blood flow as the main reasons for the good clinical results [1]. In an attempt to further explain the mechanism of action, we investigated the pressure distribution on the foam interface, and the influence on perfusion in a pre-experimental design. MATERIALS AND METHODS: Pressure distribution was measured using a sensor based on a capacitive dielectric elastomer with flexible electrodes. In vitro flow measurements were done with vessel imitations in a block of 300 bloom ballistic gel to simulate soft tissue. RESULTS: A peak pressure of up to 187 mmHg (255 g/cm2) within the foam interface, as well as decreased perfusion, were found using a standard negative pressure wound therapy setup. In conclusion, negative pressure wound therapy applies positive pressure to adjacent tissue and decreases local flow. The amount of suction applied is proportional to the pressure on the foam interface and reduction in flow. CONCLUSION: In line with previous studies investigating the underlying mechanism of action, these findings may contribute to possible alterations in the use of negative pressure wound therapy, e.g. lowering suction pressure in patients with diminished peripheral blood flow.
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Terapia de Presión Negativa para Heridas , Úlcera por Presión/terapia , Fenómenos Biomecánicos , Humanos , Presión , Úlcera por Presión/fisiopatología , Flujo Sanguíneo Regional , Cicatrización de HeridasRESUMEN
AIM OF THE STUDY: Negative pressure wound therapy (NPWT) has become an established treatment modality when dealing with chronic and infected wounds. The underlying mechanism of action is still under discussion and remains controversial. Evidence exists showing rather hypoxic conditions as the main reason for the positive results and bacterial clearance. In an attempt to further explain the mechanism of action, we investigated oxygen levels within the foam interface of a NPWT device. MATERIALS AND METHODS: We used an optical sensor based on the principle of dynamic fluorescence quenching and tested five different commonly available NPWT systems used during our daily clinical routine. All measurements were done in an in vitro experimental design for at least 24â¯h and multiple vacuum intensities were investigated. RESULTS: Oxygen levels decreased as much as 22.8% and the amount of vacuum applied inversely correlated with the oxygen reduction. A stepwise increase in vacuum of 25â¯mmHg showed a linear mean drop of 2.75% per setting. All devices were able to maintain a constant level of negative pressure, and no significant difference between the various dressings was found (pâ¯>â¯0.05). CONCLUSION: Therefore, oxygen levels are decreased within the foam of NPWT dressings, likely leading to oxygen deprivation effects in the underlying wound tissue.
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Células Espumosas/metabolismo , Terapia de Presión Negativa para Heridas/instrumentación , Oxígeno/análisis , Cicatrización de Heridas/fisiología , Células Espumosas/química , Células Espumosas/fisiología , Humanos , Terapia de Presión Negativa para Heridas/normas , Terapia de Presión Negativa para Heridas/estadística & datos numéricos , Oxígeno/metabolismoRESUMEN
BACKGROUND: Reconstruction of soft tissue defects with free flaps is a common procedure in plastic and reconstructive surgery. Most postoperative complications occur within the first 48-72 hours after surgery. After postoperative complications, short perfusion restoration times may improve flap survival rates by up to 30-50%. Ratiometric fluorescence imaging is an additional or alternative method of postoperative flap monitoring. OBJECTIVE: To test the efficacy and utility of transepidermal oxygen flux imaging to evaluate postoperative skin oxygenation of free and local flaps in the first 48 hours after surgery. METHODS: The study included 32 patients (aged between 18 and 80 years; mean age 52.9) with a tissue defect covered with a free flap transplant at the Department of Plastic and Reconstructive Surgery of the University Medical Center Regensburg. Postoperative oxygen flux was measured with the 'VisiSens system' placed on the vascular pedicle as well as on the peripheral and central part of the flap. RESULTS: Values of oxygen flux were higher in case of flap congestion (0.069±0.012) or flap necrosis (0.155±0.083) than in cases without any complications (0.061±0.006). Flux values of different areas of the same flap showed only minimal differences (central part: 0.065±0.008, peripheral part: 0.070±0.009, vascular pedicle: 0.056±0.004); the level of significance was pâ=â0.904. CONCLUSION: Imaging transepidermal oxygen flux by ratiometric luminescence seems to be a reliable alternative, indirect method of postoperative flap monitoring with regard to microcirculatory function and flap viability.