Meta-analysis of the potential economic impact following introduction of absorbable antimicrobial sutures.

BACKGROUND: Despite several randomized trials, systematic reviews and meta-analyses that have demonstrated the effectiveness of antimicrobial (triclosan-coated or -impregnated) sutures (TCS), the clinical and economic impact of using these sutures compared with conventional non-antimicrobial-coated absorbable sutures (NCS) remains poorly documented. METHODS: An independent systematic review and meta-analysis of all published evidence from January 2005 to September 2016 comparing TCS with NCS was conducted. Surgical-site infection (SSI) was the primary outcome. The results of the meta-analysis were used in a decision-tree deterministic and stochastic cost model, using the National Health Service (NHS England)-based cost of inpatient admissions for infections and differential costs of TCS versus NCS. RESULTS: Thirty-four studies were included in the final assessment from an initial 163 identified citations; 20 of 34 studies were randomized, and 17 of 34 reported blinding of physicians and assessors. Using a random-effects model, the odds ratio for SSI in the TCS compared with NCS control groups was statistically significant (odds ratio 0·61, 95 per cent c.i. 0·52 to 0·73; P < 0·001). There was significant heterogeneity (I2 = 49 per cent). Using random-effects event estimates of SSI for TCS and NCS for each individual wound type, the mean savings per surgical procedure from using antimicrobial sutures were significant: £91·25 (90 per cent c.i. 49·62 to 142·76) (€105·09 (57·15 to 164·41); exchange rate 15 November 2016) across all wound types. CONCLUSION: The reviewed literature suggested that antimicrobial sutures may result in significant savings across various surgical wound types.

Measurements of chlorhexidine, p-chloroaniline, and p-chloronitrobenzene in saliva after mouth wash before and after operation with 0.2% chlorhexidine digluconate in maxillofacial surgery: a randomised controlled trial.

Chlorhexidine gluconate is used to prevent the accumulation of dental plaque and gingivitis, infection of the surgical site, and ventilator-associated pneumonia in maxillofacial surgery, but it is not clear whether the metabolites of chlorhexidine are detectable in the patient's saliva at clinically relevant concentrations. Forty-three patients who had orofacial operations were randomised to use a 0.2% chlorhexidine gluconate (n=23), or an octenidine-based, chlorhexidine-free (n=20), mouthwash once preoperatively and three times daily for five postoperative days. After the first, 8.7 (23.3) mg/L chlorhexidine (0.7%-2.5% of the total amount used) was measured in saliva. The concentration increased to 15.2 (6.2) mg/L after the second rinse (first postoperative day), and peaked at 29.4 (11.2) mg/L on the fourth postoperative day. It remained detectable for up to 12hours after the last one, but was not detectable in serum or urine at any time. The potentially carcinogenic metabolite p-chloroaniline was detectable in saliva at higher concentrations in the chlorhexidine group (0.55mg/L) than the octenidine group (0.21mg/L), and p-chloronitrobenzene was detected in both groups in only minimal concentrations (0.001-0.21mg/L). Chlorhexidine gluconate mouthwashes do increase the concentration of p-chloroaniline, but a single use seems to be safe. Whether prolonged exposure over many years may have carcinogenic potential is still not clear. Based on the hitherto unknown kinetics of p-chloroaniline in saliva, the recent recommendation of the Federal Drug Administration (FDA) in the USA to limit the use of a chlorhexidine gluconate mouthwash to a maximum of six months seems to be justified.

A narrative review of microbial biofilm in postoperative surgical site infections: clinical presentation and treatment.

OBJECTIVE: The global impact of surgical site infections (SSIs) on health-care systems is considerable: many are related to the formation of a microbial biofilm. Biofilm plays a significant role in the pathogenesis of implantable device-related infections and are also important in persistent postoperative skin and soft tissue wound infections. METHOD: PubMed and OVID databases were searched for relevant articles regarding biofilm-associated infection in surgery, including epidemiology, diagnosis, treatment and management. RESULTS: Biofilm-associated infections increase the use of health-care resources, prolong length of stay, increase cost of antibiotic therapy, result in additional surgical revisions and extend rehabilitation after discharge from health care. Staphylococcus aureus and Staphylococcus epidermidis are the most common isolates recovered from device-related infections. Early infection occurs within two weeks of implantation and is associated with intraoperative wound contamination; late-onset infections are often occult prolonging recognition by weeks, months and in some cases, years. Biofilm is a physical barrier against antibodies and granulocytic cell populations which may also impede the penetration of antibiotics. The ideal strategy for preventing biofilm-associated SSI is to prevent intraoperative contamination through compliance with effective surgical care bundles. Management of postoperative biofilm-associated infections involves surgical debridement followed by irrigation with antimicrobial agents and removal of infected devices, followed by insertion of antimicrobial adjuncts such as antimicrobial spacers, beads or sutures together with selective therapeutic agents that penetrate the mature biofilm. CONCLUSION: Biofilm-associated infections are a significant source of postoperative morbidity and mortality. Appropriate interventional strategies are warranted to reduce the risk of intraoperative contamination. DECLARATION OF INTEREST: The authors have no conflicts.

Can the design of glove dispensing boxes influence glove contamination?

BACKGROUND: Few studies have explored the microbial contamination of glove boxes in clinical settings. The objective of this observational study was to investigate whether a new glove packaging system in which single gloves are dispensed vertically, cuff end first, has lower levels of contamination on the gloves and on the surface around the box aperture compared with conventional glove boxes. METHODS: Seven participating sites were provided with vertical glove dispensing systems (modified boxes) and conventional boxes. Before opening glove boxes, the surface around the aperture was sampled microbiologically to establish baseline levels of superficial contamination. Once the glove boxes were opened, the first pair of gloves in each box was sampled for viable bacteria. Thereafter, testing sites were visited on a weekly basis over a period of six weeks and the same microbiological assessments were made. RESULTS: The surface near the aperture of the modified boxes became significantly less contaminated over time compared with the conventional boxes (P<0.001), with an average of 46.7% less contamination around the aperture. Overall, gloves from modified boxes showed significantly less colony-forming unit contamination than gloves from conventional boxes (P<0.001). Comparing all sites over the entire six-week period, gloves from modified boxes had 88.9% less bacterial contamination. CONCLUSION: This simple improvement to glove box design reduces contamination of unused gloves. Such modifications could decrease the risk of microbial cross-transmission in settings that use gloves. However, such advantages do not substitute for strict hand hygiene compliance and appropriate use of non-sterile, single-use gloves.

Infection control hazards associated with the use of forced-air warming in operating theatres.

A review is presented of the published experimental and clinical research into the infection control hazards of using forced air-warming (FAW) in operating theatres to prevent inadvertent hypothermia. This evidence has been reviewed with emphasis on the use of ultra-clean ventilation, any interaction it has with different types of patient warming (and FAW in particular), and any related increased risk of surgical site infection (SSI). We conclude that FAW does contaminate ultra-clean air ventilation; however, there appears to be no definite link to an increased risk of SSI based on current research. Nevertheless, whereas this remains unproven, we recommend that surgeons should at least consider alternative patient-warming systems in areas where contamination of the operative field may be critical. Although this is not a systematic review of acceptable randomized controlled clinical trials, which do not exist, it does identify that there is a need for definitive research in this field.

Role of oxygen in wound healing: a review of evidence.

OBJECTIVE: To review the evidence regarding the influence of oxygen as an intrinsic factor on cutaneous wound healing. METHOD: A literature search was performed using Ovid and the Cochrane Database with the search terms: 'Wound healing', 'Oxygen', 'Collagen', 'Angiogenesis', 'Inflammation' and 'Surgical Site Infection'. Human and animal studies were included if relevant and examined for methodological quality. RESULTS: There are no meta-analyses of the use of oxygen in wound healing and only two randomised controlled trials (RCTs). Studies vary in methodological quality. The majority of the data comes from animal models. In total 1568 studies on wound healing and oxygen were found. CONCLUSION: Oxygen is vital throughout wound healing, especially in the inflammatory and proliferative phases. Research suggests that patient supplementation with oxygen could enhance bacterial killing and angiogenesis, reduce surgical site infection rates and increase wound tensile strength, facilitating improved healing. CONFLICT OF INTEREST: None.

Classification of wounds at risk and their antimicrobial treatment with polihexanide: a practice-oriented expert recommendation.

Currently, there are no generally accepted definitions for wounds at risk of infection. In clinical practice, too many chronic wounds are regarded as being at risk of infection, and therefore many topical antimicrobials - in terms of frequency and duration of use - are applied to wounds. Based on expert discussion and current knowledge, a clinical assessment score was developed. The objective of this wounds at risk (W.A.R.) score is to allow decision-making on the indication for the use of antiseptics on the basis of polihexanide. The proposed clinical classification of W.A.R. shall facilitate the decision for wound antisepsis and allow an appropriate general treatment regimen with the focus on the prevention of wound infection. The W.A.R. score is based on a clinically oriented risk assessment using concrete patient circumstances. The indication for the use of antiseptics results from the addition of differently weighted risk causes, for which points are assigned. Antimicrobial treatment is justified in the case of 3 or more points.

Plasminogen activator system in oral squamous cell carcinoma.

BACKGROUND: The plasminogen activator system consists of two plasminogen activators, urokinase (uPA) and tissue (tPA); PA inhibitors (PAI-1, and -2), and a cell surface receptor for uPA (uPAR). The plasminogen activator system is involved at many stages of the metastatic cascade, including matrix remodelling, cell proliferation, and migration. AIMS: To compare tissue concentrations of the components of the plasminogen activator system in paired tumour tissue and normal tissue in patients with oral squamous cell carcinoma, and to correlate these with the histopathological grading of the tumour. METHODS: Thirty-eight paired tissue samples were analysed by enzyme-linked immunosorbent assays (ELISA; ng/mg protein) for uPA, tPA, uPAR, PAI-1, and PAI-2. RESULTS: Concentrations of uPA, uPAR, PAI-1, and PAI-2 were significantly higher in tumour than in normal oral tissue (median in uPAR tumour 1.6 (range; 0.1-7.5) ng/mg protein; normal=0.2 (0-2.3), p<0.05). There were strong correlations between the concentrations of certain components of the plasminogen activator system in particular between uPA, uPAR, and PAI-1 (p<0.05). Tissue concentrations of some components of the plasminogen activator system correlated with clinical and pathological indexes of aggression of tumours, including differentiation and T-stage. CONCLUSION: The relation between components of the plasminogen activator system, in particular uPA, uPAR, and PAI-1 in invasion, metastasis, prognosis, and survival, requires further investigation in oral squamous cell carcinomas.

Randomized clinical trial of perioperative systemic warming in major elective abdominal surgery.

BACKGROUND: Hypothermia is common in the operating theatre and may increase susceptibility to postoperative complications. Intraoperative systemic warming has been shown to improve outcomes of surgery. This study aimed to examine the effects of additional perioperative systemic warming on postoperative morbidity. METHODS: All patients admitted for elective major abdominal surgery and fulfilling the inclusion criteria were randomized into control or warming groups. Both groups were warmed during surgery, but patients in the warming group were additionally warmed 2 h before and after surgery using a conductive carbon polymer mattress. RESULTS: The trial recruited 103 patients (56 in the control group, 47 in the warming group). Both groups were well matched for age, sex and clinical state. Patients in the warming group had lower blood loss (median 200 (range 5-1000) ml versus median 400 (range 50-2300) ml in the control group; P = 0.011) and complication rates (15 (32 per cent) of 47 versus 30 (54 per cent) of 56 in the control group; P = 0.027). There were three deaths; two in the control group (P = 0.566). CONCLUSION: Extending systemic warming to the perioperative period had additional beneficial effects, with minimal additional cost and patient discomfort.

The impact of warming on pain and wound healing after hernia surgery: a preliminary study.

OBJECTIVE: To determine whether the application of warmth after hernia surgery reduces pain and aids wound healing. METHOD: Forty-five patients were recruited and randomised to receive either no warming;two hours of warming immediately after surgery; or seven days of warming. RESULTS: Postoperative pain scores were significantly lower after two hours of warming immediately after surgery compared with the non-warmed patients (p<0.05). Pain scores were lower on each of the first seven postoperative days in the warmed groups compared with the non-warmed subjects. Patients in the warmed groups also had lower ASEPSIS wound scores. CONCLUSION: Warming may allow wounds to heal with fewer complications. In addition, warming for only two hours immediately after surgery may provide similar benefits to seven days of warming.

The matrix metalloproteinase system in oral squamous cell carcinoma.

BACKGROUND: The matrix metalloproteinase (MMP) system is responsible for degradation of tissue in both normal and pathological processes, including tumour invasion and metastasis. AIM: To compare tissue concentrations of components of the MMP system between tumour tissue and normal tissue in patients with oral squamous cell carcinoma, and to correlate concentrations with pathological grade of tumour. METHODS: Thirty-eight paired tissue samples from tumours and normal tissue were analysed by three laboratory techniques: firstly, enzyme linked immunosorbent assays (ELISA) in ng/mg protein for MMP-1, MMP-3, and tissue inhibitors of metalloproteinases (TIMPs) -1 and -2. Secondly, gelatinase activity assays to measure concentrations of total and endogenous active gelatinases, MMP-2 and MMP-9 (ng/mg protein). And thirdly to use quenched fluorescent substrate hydrolysis to measure total MMP activity (pM/min). RESULTS: The concentration of all MMPs was significantly higher in tumour than in normal oral tissue (p < 0.05, Mann-Whitney U-test). Tissue concentrations of some of these factors correlated with clinical and pathological indices of aggressiveness of tumours, including T-stage, N-stage, tumour differentiation, and anatomical level of involved nodes. However, the study was not powered to show statistical significance. CONCLUSION: It is the balance between proteinases and their inhibitors that controls tissue degradation at each stage of tumour invasion and metastasis. Measurement of MMPs in oral mucosal biopsy samples may establish the invasive potential of tumours at their initial presentation.

Antibiotic regimens for secondary peritonitis of gastrointestinal origin in adults.

BACKGROUND: Secondary peritonitis is associated with a high mortality rate and if not treated successfully leads to development of abscesses, severe sepsis and multi-organ failure. Source control and adjunctive antibiotics are the mainstay of treatment. However, no conclusive evidence suggest that one antibiotic regimen is better than any other but at the same time have a lower toxicity. OBJECTIVES: To ascertain the efficacy and adverse effects of different antibiotic regimens in treating intra-abdominal infections in adults. Outcomes were divided into primary (clinical success and effectiveness in reducing mortality) and secondary (microbiological success, preventing wound infection, intra-abdominal abscess, clinical sepsis, remote infection, superinfection, adverse reactions, duration of treatment required, effectiveness in reducing hospitalised stay, and time to defervescence). SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library, Issue 4, 2004), MEDLINE (from 1966 to November 2004), EMBASE (from 1980 to November 2004) and Cochrane Colorectal Cancer Group specialised register SR-COLOCA. Bibliographies of identified studies were screened for further relevant trials. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing different antibiotic regimens in the treatment of secondary peritonitis in adults were selected. Trials reporting gynaecological or traumatic peritonitis were excluded from this review. Ambiguity regarding suitability of trials were discussed among the review team. DATA COLLECTION AND ANALYSIS: Six reviewers independently assessed trial quality and extracted data. Data collection was standardised using data collection form to ensure uniformity among reviewers. Statistical analyses were performed using the random effects model and the results expressed as odds ratio for dichotomous outcomes, or weight mean difference for continuous data with 95% confidence intervals. MAIN RESULTS: Fourty studies with 5094 patients met the inclusion criteria. Sixteen different comparative antibiotic regimens were reported. All antibiotics showed equivocal comparability in terms of clinical success. Mortality did not differ between the regimens. Despite the potential high toxicity profile of regimens using aminoglycosides, this was not demonstrated in this review. The reason for this could be the inherent bias within clinical trials in the form of patient selection and stringency in monitoring drug levels. AUTHORS' CONCLUSIONS: No specific recommendations can be made for the first line treatment of secondary peritonitis in adults with antibiotics, as all regimens showed equivocal efficacy. Other factors such as local guidelines and preferences, ease of administration, costs and availability must therefore be taken into consideration in deciding the antibiotic regimen of choice. Future trials should attempt to stratify patients and perform intention-to-treat analysis to allow better external validity.

Day-case breast cancer axillary surgery.

INTRODUCTION: The standard locoregional management of breast cancer is excision of the primary tumour and axillary staging with suction drainage of the axilla. The objective of this study was to determine the safety, tolerability and efficacy of day-case surgery without suction drainage. PATIENTS AND METHODS: A review of complete, prospectively collected data was performed on all breast cancer patients (screening and symptomatic) planned to undergo day-case axillary surgery at a University Teaching Hospital between 2000 and 2002. Postoperative complications were recorded and the notes of patients not discharged on the day of their surgery were also examined to establish the reason for overnight stay. RESULTS: 165 patients underwent intended day-case axillary surgery (axillary dissection level 1/2; median age, 55 years; range, 39-76 years). Of these, 16 (9.7%) were admitted overnight usually due to over-running of theatre lists (n = 13; 81%). 29 patients (17.6%) underwent axillary dissection alone, the remainder had axillary surgery combined with wide local excision (median number of lymph nodes excised 11; range, 2-18). Complications included symptomatic seroma formation in 37 patients (22%) and wound infection in 16 patients (10%). CONCLUSIONS: Day-case axillary surgery can be performed safely with surgical morbidity comparing favourably to published work of 'traditional' axillary drainage following lymphadenectomy.

Effects of warming on healing.

Systemic and local warming may accelerate wound healing and minimise postoperative wound infection, although more research is needed to confirm this. The existing evidence of the benefits of warming therapies is outlined here.

Sequential physiology scoring facilitates objective assessment of resuscitation in patients with an intra-abdominal emergency.

BACKGROUND: Patients who present with an intra-abdominal emergency often require urgent surgery. Before surgery a period of resuscitation is undertaken pre-emptively, or to correct any overt physiological derangement. The assessment of response to resuscitation and the decision when to operate is subjective. This study examined the role of sequential physiology scores in assessing the response to resuscitation objectively. METHODS: Sequential physiology scores were recorded in 92 patients with abdominal pathology that subsequently required urgent or emergency surgery. The physiology component of the Physiological and Operative Severity Score for enUmeration of Mortality and morbidity (POSSUM), Acute Physiology And Chronic Health Evaluation (APACHE) II and III, and Simplified Acute Physiology Score (SAPS) II were determined at presentation, during resuscitation and immediately before surgery. RESULTS: There were 76 survivors;16 patients died. All scoring systems showed an improvement during resuscitation but subsequent deterioration before surgery. The POSSUM, and APACHE II and III physiology scores differentiated more effectively between survivors and patients who died than SAPS II. CONCLUSION: Sequential physiology scores may facilitate the assessment of patients' response to resuscitation. Patients who fail to respond to resuscitation when identified may benefit from more expedient surgery.