Efficacy of Negative Pressure Therapy to Enhance Take of 1-Stage Allodermis and a Split-Thickness Graft

Securing skin grafts: A network meta-analysis

BACKGROUND

Skin grafting is one of the most common procedures in plastic surgery. However, there are no defined guidelines for optimal fixation. The aim of this network meta-analysis (NMA) was to consolidate existing evidence by comparing various graft securing methods and determining the most effective approach for clinical practice.

METHODS

An NMA was conducted using a predetermined protocol after searching several electronic databases from inception to October 2023 for studies examining skin grafting fixation outcomes in adults.

RESULTS

A total of 27 studies were included in the analysis involving 1937 patients. Negative pressure wound therapy (NPWT) was the only method to significantly improve graft take percentages in comparison with the other modalities, whereas tie-over bolster (TOB) provided the worst results in take rates when examined as events. Fibrin glue (FIB) and TOB reduced hematoma and seroma rates when data were investigated in conjunction.

CONCLUSIONS

NPWT appears to be the most effective for skin graft adherence as opposed to traditional techniques. Its cost-effectiveness remains unclear, as NPWT is a relatively costly intervention compared with other methods. FIB and TOB are methods that can serve as a method of reducing hematoma and seroma rates in patients at high risk of bleeding.

LEVEL OF EVIDENCE

I.

Continuous negative-pressure wound therapy improves the survival rate of skin grafts and shortens the time required for skin graft survival

BACKGROUND

The effectiveness of negative-pressure wound therapy (NPWT) in skin graft fixation has been demonstrated in several clinical studies. However, in vitro and in vivo studies on skin graft fixation with NPWT have been scarce. In this in vivo study, we aimed to determine whether NPWT fixation enhances skin graft survival and how it contributes to improving skin graft survival biologically.

MATERIALS AND METHODS

We harvested skin from the bilateral abdominal wall of 88 mice after anesthetizing them. Full-thickness skin grafts (FTSGs) were performed on contralateral harvest sites, and grafts were fixed using NPWT (continuous and intermittent modes), conventional compression methods, and wrapping with polyurethane foam as a control group. On days 5 and 10 of grafting, the survival rates of the FTSGs were evaluated. Immunohistopathological analysis and measurement of the expression levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF-2), and epidermal growth factor (EGF) were performed.

RESULTS

The survival rates of FTSG in the continuous NPWT group were significantly higher than those in the other groups. The number of capillaries in the dermis was significantly higher in the continuous NPWT group than in the other groups. In the wound bed, VEGF levels were significantly higher in both NPWT groups than in the other groups.

CONCLUSION

Continuous NPWT increases the survival rate of FTSGs and shortens the duration of skin graft survival.

Prevalence of surgical site wound infection after spine surgery in nasal colonization of methicillin-resistant Staphylococcus aureus: A meta-analysis

The purpose of the meta-analysis was to evaluate and compare the prevalence of surgical site infection (SSI) after spine surgery (SS) in nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA). The results of this meta-analysis were analysed, and the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) were calculated using dichotomous or contentious random- or fixed-effect models. For the current meta-analysis, 14 examinations spanning from 2014 to 2022 were included, encompassing 18 410 people who were tested for nasal colonization after SS. MRSA-positive had a significantly higher SSI (OR, 3.65; 95% CI, 2.48-5.37, p < 0.001) compared with MRSA-negative in SS subjects. However, no significant difference was found between methicillin-susceptible Staphylococcus aureus and Staphylococcus aureus negative (OR, 0.94; 95% CI, 0.32-2.79, p = 0.91), and Staphylococcus aureus positive and negative (OR, 2.13; 95% CI, 0.26-17.41, p = 0.48) in SS subjects. The examined data revealed that MRSA colonization had a significant effect on SSI; however, methicillin-susceptible Staphylococcus aureus and Staphylococcus aureus had no significant effect on SSI in SS subjects. However, given that some comparisons included a small number of chosen studies, attention should be given to their values.

Evaluation of wound healing effects of micronized acellular dermal matrix in combination with negative pressure wound therapy: In vivo study

Acellular dermal matrix (ADM) grafts can provide coverage for full-thickness skin defects and substitute for dermal defects. We tested the effectiveness of micronized ADM (mADM) as a dressing material, combined with negative pressure wound therapy (NPWT), for managing superficial wounds. We compared the wound healing effect of mADM in combination with NPWT with those of gelatin and mADM applied with a foam dressing. These therapeutic materials were applied to 36 cm² excisional wounds in a porcine full-thickness skin defect model. Wound healing kinetics and new tissue formation were assessed 10 days after the initial treatment by measuring the wound area. Collagen deposition and neovascularization were histologically evaluated. Compared with the other two groups, mADM plus NPWT combination group had a significantly larger wound area at the baseline (P = .0040), but the smallest on the 7th day (P = .0093). In addition, collagen formation and neovascularization were more histologically promoted than in the other two groups. mADM showed better results than the gelatin group but less collagen and revascularization than the combination group, and there was no significant difference in wound area. Our results show that the combination of mADM and NPWT has a synergistic wound healing effect.

Combined negative pressure wound therapy with irrigation and dwell time and artificial dermis prevents infection and promotes granulation formation in a ruptured giant omphalocele: a case report

Background

Omphalocele is a congenital abdominal wall defect of the umbilical cord insertion site. A giant omphalocele, with a fascial defect > 5 cm in diameter and/or containing > 50% of the liver within the hernia sac, can be challenging for pediatric surgeons. Recently, negative pressure wound therapy has been reported as an effective management for giant omphaloceles; however, it is not recommended for an infected wound with necrotic tissue as it may exacerbate infection. We adopted negative pressure wound therapy with irrigation and dwell time (NPWTi-d) for a case of a ruptured giant omphalocele. Artificial membranes, followed by artificial dermis, were used to promote fibrous capsule formation, and then NPWTi-d was used to promote granulation while controlling infection. However, studies have not been conducted regarding NPWTi-d for ruptured giant omphaloceles; hence, we present our treatment experience with NPWTi-d for a giant omphalocele.

Case presentation

The patient was a boy born at 38 weeks and 3 days of gestation, weighing 1896 g. He was diagnosed with a ruptured giant omphalocele with a total liver and intestine defect hole of 10 cm × 10 cm. The patient underwent silo placement using an artificial mesh, followed by plicating the artificial mesh at 4 days of age. The herniated viscera were gradually reduced into the abdominal cavity; however, the defect size was still large. Hence, a collagen-based artificial dermis was patched on the defect hole. After creating a fresh and smooth granulated tissue, NPWTi-d was applied at 33 days of age to promote granulation and control infection. We used the 3 M™ V.A.C.® Ulta Therapy Unit with 3 M™ VeraFlo™ therapy. NPWTi-d was stopped at 60 days of age when the granulation tissue was well formed including at the artificial dermis site. The wound was managed with prostandin ointment and appropriate debridement, resulting in complete epithelialization at 5 months of age.

Conclusions

Artificial membranes followed by artificial dermis were used to promote a fibrous capsule and artificial dermis granulation, which protects against organ damage. NPWTi-d achieved better control of infection and promoted wound healing. NPWTi-d combined with artificial dermis can effectively treat ruptured giant omphaloceles.

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.

Safeguarding Skin Grafts: An Evidence-Based Summary of Fixation Techniques

BACKGROUND

Effective skin graft fixation is vital in preventing sheering forces, seroma, and hematoma from compromising graft take. Yet, selecting the ideal technique for securing skin grafts remains a contentious subject, with significant variation in practice existing between surgeons. There is, therefore, benefit to be derived from assessing the literature for evidence-based recommendations to guide the decision-making process.

METHODS

A search of Medline and Embase was performed using appropriate key terms, yielding 419 articles. Reference lists were analyzed. Inclusion and exclusion criteria were composed. Level I to III studies, as defined by the Centre for Evidence-Based Medicine, that compared skin graft fixation methods were analyzed. Rayyan QCRI was used for abstract and title screening. After full text screening, 41 studies were included for qualitative analysis. All included randomized control trials (RCTs) were assessed for risk of bias using the Cochrane Risk-of-Bias 2 (ROB2) tool.

RESULTS

We identified 4 groups of fixation technique: "tie-over bolster" (TOB), "no TOB," "adhesive glues," and "negative pressure wound therapy" (NPWT). Twelve studies compared TOB with no TOB, with no difference in graft take demonstrated. Sixteen studies compared adhesive glues with traditional methods, with no difference in graft take demonstrated. Thirteen studies compared NPWT with traditional methods, with enhanced graft take demonstrated. Risk of bias was deemed low in 1 of 13 RCTs.

CONCLUSIONS

Based on the current evidence, only NPWT is associated with enhanced graft take. However, there is a scarcity of robust level I evidence comparing different fixation techniques, meaning that strong recommendations cannot be made. We propose examples of hypothesis-driven RCTs, in predetermined clinical settings, based on the theoretical benefits of the techniques that would add value to clinical practice.

Filling the vacuum: Role of negative pressure wound therapy in open wound management in cats

Practical relevance:

Open wounds and their treatment present a common challenge in veterinary practice. Approaching 15 years ago negative pressure wound therapy (NPWT) started to be incorporated into clinical veterinary medicine, and its availability is becoming more widespread in Europe and the USA. Use of this therapy has the potential to significantly increase the healing rate of open wounds as well as free skin grafts in small animals, and it has been occasionally described for the management of feline wounds.

Aim:

This review describes the mechanisms of action of, and indications for, NPWT, and offers recommendations for NPWT specific to feline patients.

Evidence base:

The information presented is based on the current evidence and the author’s clinical experience of the technique gained over the past 12 years. Comparative studies of different treatment options are lacking and, since wound healing in cats and dogs differs, cat-specific studies are especially needed. Well-designed wound healing studies comparing different advanced techniques will improve open wound healing in cats in the future, and potentially allow better understanding of the role of NPWT in this setting.

Negative-pressure wound therapy combined with artificial dermis (Terudermis) followed by split-thickness skin graft might be an effective treatment option for wounds exposing tendon and bone: A retrospective observation study

Skin grafts are not suitable for closing tendon- or bone-exposing wounds, which require flap surgery. Dermal regeneration templates have value for closing such wounds, but the disadvantages of the technique include implantation failures because of infection, hematoma formation, or inappropriate immobilization. Negative-pressure wound therapy was reported to increase graft acceptance in difficult wounds.This retrospective case series of 65 patients evaluated negative-pressure therapy combined with artificial dermis for the treatment of acute or chronic tendon- or bone-exposing wounds. The artificial dermis was placed after adequate wound-bed preparation, with simultaneous application of a vacuum-assisted closure system. Split-thickness skin grafting was performed after the implanted artificial dermis had become established.The overall success rate was 88.1% (59/67): 88.6% (39/44) in the chronic wounds group and 87% (20/23) in the acute-trauma group separately. The overall mean survival time of artificial dermis in success cases was 13.24 ± 7.14 days. In separately, the survival time of artificial dermis had no statistically difference in chronic wound group (13.64 ± 7.53 vs 12.60 ± 5.86. P = .943), but had significant statistical difference in acute trauma group (12.45 ± 6.44 days vs 23.33 ± 4.04 days, P = .018). Also, comorbidity of PAOD was found a strong risk factor of failure in chronic wound group (100% vs 23.1%, P < 0.001).We concluded that artificial dermis combined with negative-pressure therapy followed by split-thickness skin grafting might be a reliable and effective option for surgical reconstruction of tendon- or bone-exposing wounds, and could decreasing waiting periods of autologous skin graft.

Recent strategic approach in postburn extremity scars and contractures

This study aims to present the outcomes from current alternative treatment modalities combined with the conventional techniques used in the treatment of burn contractures. Twenty-nine patients were included in the study. Patients were divided into three groups according to the severity of contractures: 1- mild, 2- moderate, and 3- severe. Skin defects that occurred following the incision and scar contracture release were closed with a collagen-elastin acellular dermal matrix (ADM). The split-thickness skin graft was evenly placed on the ADM and fixed with absorbable sutures. The grafts were closed with NPWT (negative pressure wound therapy system) dressings. In platelet-rich plasma (PRP) mild cases as well as moderate and severe PRP cases, stem cell and fat injection were applied. PRP injection was applied to the scar base before the contracture; fat injection and stem cells were applied at the 3rd and 6th months. Preoperative and postoperative range of motion (ROM), Patient and Observer Scars Evaluation Scale (POSAS), and histopathological scores were evaluated. There was a statistically significant decrease in postoperative POSAS scores (p < .05) and a significant increase in the ROM score (p < .05). Histopathological examination revealed an increased postoperative collagen accumulation and organization, increased vascularization, decreased scar tissue thickness and increased subcutaneous tissue thickness. There was no difference in treatment outcomes between the groups.Based on the current findings, we conclude that ADM, stem cell-rich fat grafting, and PRP therapies combined with conventional methods could satisfactorily improve functional outcomes in the repair of burn contractures.

Split Thickness Skin Graft of the Foot and Ankle Bolstered With Negative Pressure Wound Therapy in a Diabetic Population: The Results of a Retrospective Review and Review of the Literature

Split thickness skin graft (STSG) is a versatile procedure performed for the treatment of wounds resulting from varying pathology. This remains very useful because of its ability for quick healing and low complication rate. The surface of the foot and ankle is an area frequently affected by severe skin and soft tissue structure infections (SSTIs) whose treatment results in wounds. These infections and resultant surgical wounds are commonly seen patients with diabetes. The objective of the present study was to retrospectively evaluate initial healing and immediate post-operative outcomes following STSG application in a diabetic population when negative pressure wound therapy (NPWT) was used as a bolster. Ten patients were identified, including 11 surgical wounds, who underwent STSG bolstered with NPWT from January 2016 to October 2018. Mean follow-up was 13 months (range 1-33 months) with an average time to heal of 17 days (range 14-30 days) for 11 surgical wounds averaging 57 cm2 (range 6.3 - 91 cm2). Consistent improved outcomes have been demonstrated when compared to alternative bolstering techniques available in the literature making a STSG bolstered with NPWT a powerful tool in the reconstruction of diabetic foot wounds resulting from the treatment of infection.Levels of Evidence: Level IV.

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.

Vakuumassistierte Wundbehandlung (Negative Pressure Wound Therapy, NPWT) in der Kleintiermedizin

Die Behandlung offener Wunden gehört zu den alltäglichen Herausforderungen in der Tiermedizin. In den letzten Jahren hat sich mit der vakuumassistierten Wundbehandlung (Negative Pressure Wound Therapy, NPWT) eine neue Therapieform entwickelt. Durch ihren Einsatz lassen sich die Heilung offener Wunden und die Einheilungsrate freier Hauttransplantate beim Kleintier signifikant verbessern. In diesem Überblick werden Wirkweise, Indikationen sowie Komplikationen der Negative Pressure Wound Therapy dargestellt.

Effects of Incisional Negative-Pressure Wound Therapy on Primary Closed Defects after Superficial Circumflex Iliac Artery Perforator Flap Harvest: Randomized Controlled Study

BACKGROUND

Prolonged hematoma or seroma after primary closure is a causative element in wound complications. This study evaluated the effects of negative-pressure wound therapy on primary closed wounds after superficial circumflex iliac artery perforator flap harvest.

METHODS

This study was a prospective, randomized, clinical trial comparing conventional dressing against a single application of negative-pressure wound therapy for 5 days after primary closure. A total of 100 patients who had superficial circumflex iliac artery perforator flap harvest were enrolled.

RESULTS

There was no statistical difference between the incisional negative-pressure wound therapy and conventional dressing groups in the distribution of risk factors. Significant findings were noted for duration and amount of closed suction drainage: 6.12 ± 4.99 days (median, 4 days; range, 3 to 8 days) and 100.47 ± 140.69 cc (median, 42 cc) for wounds treated with conventional dressing versus 3.34 ± 1.35 days (median, 3 days; range, 2 to 4 days) and 23.28 ±18.36 cc (median, 20 cc) for wounds in treatment group (p = 0.0077 and p = 0.0004), respectively. After closure, an increase in skin perfusion were noted on day 5 in the treatment group (p = 0.0223). There was one case of wound dehiscence in the conventional dressing group.

CONCLUSION

The incisional negative-pressure wound therapy has a positive effect over primary closed surgical defects by significantly reducing the amount of fluid collected by closed suction drains, allowing earlier removal of drains and enhancing the skin perfusion on the repaired skin.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Negative Pressure Wound Therapy in the Management of Combat Wounds: A Critical Review

Significance: Wounds sustained in a combat trauma often result in a composite tissue loss. Combat injuries, due to high energy transfer to tissues, lead to trauma at multiple anatomical sites. An early wound cover is associated with lower rate of infections and a faster wound healing. The concept of negative pressure wound therapy (NPWT) in the management of combat-related wounds has evolved from the civilian trauma and the wounds from nontraumatic etiologies. Recent Advances: Encouraged by the results of NPWT in noncombat-related wounds, the military surgeons during Operation Iraqi Freedom and Operation Enduring Freedom used this novel method in a large percentage of combat wounds, with gratifying results. The mechanism of NPWT in wound healing is multifactorial and often complex reconstructive procedure can be avoided in a combat trauma setting. Critical Issues: Wounds sustained in military trauma are heavily contaminated with dirt, patient clothing, and frequently associated with extensive soft tissue loss and osseous destruction. Delay in evacuation during an ongoing conflict carries the risk of systemic infection. Early debridement is indicated followed by delayed closure of wounds. NPWT helps to provide temporary wound cover during the interim period of debridement and wound closure. Future Directions: Future area of research in combat wounds is related to abdominal trauma with loss of abdominal wall. The concept of negative pressure incisional management system in patients with a high risk of wound breakdown following surgery is under review, and may be of relevance in combat wounds.

Skin tissue engineering advances in severe burns: review and therapeutic applications

Current advances in basic stem cell research and tissue engineering augur well for the development of improved cultured skin tissue substitutes: a class of products that is still fraught with limitations for clinical use. Although the ability to grow autologous keratinocytes in-vitro from a small skin biopsy into sheets of stratified epithelium (within 3 to 4 weeks) helped alleviate the problem of insufficient donor site for extensive burn, many burn units still have to grapple with insufficient skin allografts which are used as intermediate wound coverage after burn excision. Alternatives offered by tissue-engineered skin dermal replacements to meet emergency demand have been used fairly successfully. Despite the availability of these commercial products, they all suffer from the same problems of extremely high cost, sub-normal skin microstructure and inconsistent engraftment, especially in full thickness burns. Clinical practice for severe burn treatment has since evolved to incorporate these tissue-engineered skin substitutes, usually as an adjunct to speed up epithelization for wound closure and/or to improve quality of life by improving the functional and cosmetic results long-term. This review seeks to bring the reader through the beginnings of skin tissue engineering, the utilization of some of the key products developed for the treatment of severe burns and the hope of harnessing stem cells to improve on current practice.

Negative pressure wound therapy augmented full-thickness free skin grafting in the cat: outcome in 10 grafts transferred to six cats

OBJECTIVES

The aim of this clinical evaluation was to describe the technique and outcomes of negative pressure wound therapy (NPWT) augmented skin grafting in cats.

METHODS

Cats with soft tissue and skin defects (n = 6) underwent open wound management. Wounds were initially covered using a NPWT system that was changed to polyurethane foam dressing once infection was controlled and granulation started. Final closure was achieved after establishment of a healthy, fully granulated wound bed by grafting of free full-thickness skin from the lateral abdominal wall. The freshly grafted skin was then treated with an NPWT dressing at a pressure of -125 mmHg for 3 days, with dressing changes performed daily. Percentage graft take, complications, wound bioburden and cosmetic outcome were recorded.

RESULTS

The mean duration of open wound management was 21.4 days (range 3.0-45.0 days), with a mean duration of NPWT of 8.0 days (range 3.0-14.0 days). Five cats received a single graft, while one cat had five grafts transferred to the right hindlimb. In 7/10 grafts, graft take was 100%, in two grafts take was 95% and in one graft take was 80% (mean take rate 97%). Therapy was well tolerated in all patients. The grafted site displayed normal hair regrowth in four cats, sparse hair regrowth in one and no hair growth at all in one patient. Skin sensation was normal in all grafted patients.

CONCLUSIONS AND RELEVANCE

Skin graft augmentation using NPWT in cats is a feasible option that allows graft fixation, even in anatomically demanding areas. Graft take rate reported here is slightly higher than documented in previous reports.

Prospective randomized controlled trial comparing two methods of securing skin grafts using negative pressure wound therapy: vacuum-assisted closure and gauze suction

Negative pressure wound therapy (NPWT) has revolutionized the management of complicated wounds and has contributed an additional modality for securing split thickness skin grafts (STSG). The standard for NPWT is the vacuum-assisted closure (VAC) device. The authors' institution has accumulated experience using standard gauze sealed with an occlusive dressing and wall suction (GSUC) as their primary mode for NPWT. The authors report a randomized controlled trial comparing the efficacy of the GSUC vs the VAC in securing STSG. A prospective, randomized, controlled trial was conducted in 157 wounds in 104 patients requiring STSG from August 2009 to July 2012. All wounds were randomized to VAC or GSUC treatment and assessed for skin graft adherence/take. At postoperative day 4 or 5, NPWT was discontinued, and the size of the graft and any nonadherent areas were measured and recorded. Concomitant comorbidities, wound location, etiology, study failures, and reoperative rates were also reviewed. In all, 77 and 80 wounds were randomized to the GSUC and VAC study arms. Patient demographics were similar between both groups in terms of age, sex, comorbidities, etiology, and wound location. In all, 64 of 80 wounds in the GSUC group and 60 of 77 wounds in the VAC group had full take of the skin graft by postoperative day 4 or 5 (P = .80). The mean percent take in the GSUC group was 96.12% vs 96.21% in the VAC arm (P = .98). The use of NPWT in securing STSG is a useful method to promote adherence and healing. This study demonstrates that a low-cost, readily accessible system utilizing gauze dressings and wall suction (GSUC) results in comparable skin graft take in comparison to the VAC device.

Exposed tibial bone after burns: Flap reconstruction versus dermal substitute

A 44 years old male patient had suffered extensive 3rd degree burns on both legs, undergoing thorough surgical debridement, resulting in both tibias being exposed. Approximately 5 months after the incident he was referred to the Department of Plastic and Reconstructive Surgery of the University Hospital Gent, Belgium, to undergo flap reconstruction. Free flap surgery was performed twice on both lower legs but failed on all four occasions. In between flap surgery, a dermal substitute (Integra(®)) was applied, attempting to cover the exposed tibias with a layer of soft tissue, but also without success. In order to promote the development of granulation tissue over the exposed bone, small holes were drilled in both tibias with removal of the outer layer of the anterior cortex causing the bone to bleed and subsequently negative pressure wound therapy (NPWT) was applied. The limited granulation tissue resulting from this procedure was then covered with a dermal substitute (Glyaderm(®)), consisting of acellular human dermis with an average thickness of 0.25mm. This dermal substitute was combined with a NPWT-dressing, and then served as an extracellular matrix (ECM), guiding the distribution of granulation tissue over the remaining areas of exposed tibial bone. Four days after initial application of Glyaderm(®) combined with NPWT both tibias were almost completely covered with a thin coating of soft tissue. In order to increase the thickness of this soft tissue cover two additional layers of Glyaderm(®) were applied at intervals of approximately 1 week. One week after the last Glyaderm(®) application both wounds were autografted. The combination of an acellular dermal substitute (Glyaderm(®)) with negative pressure wound therapy and skin grafting proved to be an efficient technique to cover a wider area of exposed tibial bone in a patient who was not a candidate for free flap surgery. An overview is also provided of newer and simpler techniques for coverage of exposed bone that could question the universal plastic surgery paradigm that flap surgery is the only way to cover these defects.

Using a Contradictory Approach to Treat a Wound Induced by Hematoma in a Patient With Antiphospholipid Antibody Syndrome Using Negative Pressure Wound Therapy: Lessons Learnt

A 48-year-old woman with antiphospholipid syndrome (APS) had multiple skin necrosis caused by massive bleeding and hematoma collection at the right lower leg, left thigh, and abdomen. During the first month, we did surgical debridement every 2 to 3 days with meticulous coagulation and applied negative pressure wound therapy (NPWT). Then as the base showed initial granulation, we changed the NPWT every 4 days. NPWT was used with lower pressure and cyclic mode (-40 to -75 mm Hg) to minimize trauma and to reduce the possibility of bleeding from the wounds. After 2 months of NPWT treatment, all the wounds eventually healed with secondary intension despite the patient's condition with diabetes, hemodialysis, anticoagulant use, and corticosteroid therapy. This report supports the idea that if accompanied by conservative debridement with meticulous bleeding control, application of NPWT in low pressures and close monitoring of the patient, NPWT is possible to use even in wounds of patients with risk for bleeding.

Soft tissue coverage of the mangled upper extremity

Mangled upper extremity injuries usually involve high-impact trauma with crushing and tearing of the limb and its associated soft tissue structures. Such trauma is particularly mutilating because of the nature of the injury and the involvement of structures vital for proper function. Although advancements in flap technique and improvements in bone fixation methods have enabled good functional and clinical outcomes in limb salvage reconstruction, this remains a challenging area. Attempts at limb preservation should be fully exhausted before consideration is given for amputation, which results in significantly decreased function. Here the authors focus on the various modalities of soft tissue coverage available including allogenic substitutes, the adjunctive use of negative pressure wound therapy, and the design and utilization of flaps to address various defect configurations for the goals of wound healing, aesthetics, and functional restoration in the mangled upper extremity.

Soft tissue coverage of the upper extremity: an overview

Prehension is a complex function of the hand that gives it mechanical precision combined with a standard sensory pattern. The priority in soft tissue reconstruction for the upper extremity is to restore function. Significant injury to the upper extremity may result after trauma because of various etiologies. The timing and choice of soft tissue coverage for upper extremity defects warrant special consideration to avoid prolonged immobilization, which can result in joint stiffness, tendon adhesions, scar contractures, and ultimately, loss of function. This article reviews the various reconstructive options and considerations involved in providing coverage for upper extremity soft tissue defects.

Negative pressure wound therapy for skin grafts and surgical wounds healing by primary intention

BACKGROUND

Indications for the use of negative pressure wound therapy (NPWT) are broadening with a range of systems now available on the market, including those designed for use on clean, closed incisions and skin grafts. Reviews have concluded that the evidence for the effectiveness of NPWT remains uncertain, however, it is a rapidly evolving therapy. Consequently, an updated systematic review of the evidence for the effects of NPWT on postoperative wounds expected to heal by primary intention is required.

OBJECTIVES

To assess the effects of NPWT on surgical wounds (primary closure, skin grafting or flap closure) that are expected to heal by primary intention.

SEARCH METHODS

We searched the following electronic databases to identify reports of relevant randomised clinical trials: the Cochrane Wounds Group Specialised Register (searched 28 January 2014); the Cochrane Central Register of Controlled Trials (CENTRAL; 2013, issue 12); Database of Abstracts of Reviews of Effects (2013, issue 12); Ovid MEDLINE (2011 to January 2014); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 24 January 2014); Ovid EMBASE (2011 to January 2014 Week 44); and EBSCO CINAHL (2011 to January 2014). We conducted a separate search to identify economic evaluations.

SELECTION CRITERIA

We included trials if they allocated patients to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with a different type of NPWT.

DATA COLLECTION AND ANALYSIS

We assessed trials for their appropriateness for inclusion and for their quality. This was done by three review authors working independently, using pre-determined inclusion and quality criteria.

MAIN RESULTS

In this first update, we included an additional four trials, taking the total number of trials included to nine (785 participants). Three trials involved skin grafts, four included orthopaedic patients and two included general surgery and trauma surgery patients; all the included trials had unclear or high risk of bias for one or more of the quality indicators we assessed. Seven trials compared NPWT with a standard dressing (two of these were 'home-made' NPWT devices), one trial compared one 'home-made' NPWT with a commercially available device. In trials where the individual was the unit of randomisation, there were no differences in the incidence of surgical site infections (SSI); wound dehiscence, re-operation (in incisional wounds); seroma/haematoma; or failed skin grafts. Lower re-operation rates were observed among skin graft patients in the 'home-made' NPWT group (7/65; 10.8%) compared to the standard dressing group (17/66; 25.8%) (risk ratio (RR) 0.42; 95% CI 0.19 to 0.92). The mean cost to supply equipment for VAC® therapy was USD 96.51/day compared to USD 4.22/day for one of the 'home-made' devices (P value 0.01); labour costs for dressing changes were similar for both treatments. Pain intensity score was also reported to be lower in the 'home-made' group when compared with the VAC® group (P value 0.02). One of the trials in orthopaedic patients was stopped early because of a high incidence of fracture blisters in the NPWT group (15/24; 62.5%) compared with the standard dressing group (3/36; 8.3%) (RR 7.50; 95% CI 2.43 to 23.14).

AUTHORS' CONCLUSIONS

Evidence for the effects of negative pressure wound therapy (NPWT) for reducing SSI and wound dehiscence remains unclear, as does the effect of NPWT on time to complete healing. Rates of graft loss may be lower when NPWT is used, but hospital-designed and built products are as effective in this area as commercial applications. There are clear cost benefits when non-commercial systems are used to create the negative pressure required for wound therapy, with no evidence of a negative effect on clinical outcome. In one study, pain levels were also rated lower when a 'home-made' system was compared with a commercial counterpart. The high incidence of blisters occurring when NPWT is used following orthopaedic surgery suggests that the therapy should be limited until safety in this population is established. Given the cost and widespread use of NPWT, there is an urgent need for suitably powered, high-quality trials to evaluate the effects of the newer NPWT products that are designed for use on clean, closed surgical incisions. Such trials should focus initially on wounds that may be difficult to heal, such as sternal wounds or incisions on obese patients.

Repair of refractory wounds through grafting of artificial dermis and autologous epidermis aided by vacuum-assisted closure

BACKGROUND

This study aimed to investigate the clinical efficacy of vacuum-assisted closure (VAC) combined with grafting of artificial dermis and autologous epidermis in the repair of refractory wounds.

METHODS

Patients with refractory wounds underwent debridement. Then the VAC device was used to culture wound granulation tissue. After the wound granulation tissue began to grow, artificial dermis was grafted on the wounds with VAC treatment. Then autologous epidermis was grafted on the artificial dermis to repair the wounds after survival of the artificial epidermis. The study mainly observed length of the hospital stay, survival of the artificial dermis, time required for culture of the granulation tissue using VAC before grafting of the artificial dermis, survival time of the artificial dermis, survival conditions of the autologous epidermis, influence on functions of a healed wound at a functional part, healing conditions of donor sites, and recurrence conditions of the wounds.

RESULTS

Healing was successful for 22 patients (95.7%), but treatment failed for 1 child. The 22 patients were followed up for 6 to 24 months. According to follow-up findings, the skin grafts had good color and a soft texture. They were wear resistant and posed no influence on function. The appearance of the final results was the same as that of the full-thickness skin graft. Mild or no pigmentation and no scar formation occurred at the donor sites, and the wounds did not recur.

CONCLUSION

Vacuum-assisted closure combined with grafting of artificial dermis and autologous epidermis is an effective means for repairing refractory wounds and is worth clinical popularizing and application.

LEVEL OF EVIDENCE V

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 .

The superficial fascia as a new plane of elevation for anterolateral thigh flaps

The elevation plane for the anterolateral thigh perforator flap is either subfascial or suprafascial approach. But extensive debulking is frequently performed with possibilities of endangering viability. We hypothesized that by elevating the flap in the layer between the deep and the superficial fat, the superficial fascia, we will be able to achieve elevation of a thin and hemodynamically reliable flap without wasting human tissue. This approach was performed on 54 cases. The average weight was 68.1 kg, and average body mass index was 24.6 kg/m. Primary closure was performed on 18 cases and skin grafts on 36 cases. Evaluation for flap survival, contour of the flap, and donor site were performed. All 54 flaps were successfully elevated with at least one viable perforator with this approach. Total flap loss was noted in 1 case, resulting in a 98% survival rate. Secondary debulking was performed on 3 cases whose body mass index was >29. Regarding donor site, the primarily closed sites showed no complications, and the grafted skin over the deep fat leads to similar contour compared with the contralateral side. The study shows that this new plane can be used as a level of elevation while acting as a guide to promise adequate blood supply based on the subdermal plexus.

Advances in treating skin defects of the hand: skin substitutes and negative-pressure wound therapy

Surgeons and scientists have been developing alternative methods of hand reconstruction that may play an adjunctive role to, or completely supplant, more traditional reconstructive modalities. This article provides an overview of these emerging techniques, with an emphasis on skin substitutes and negative-pressure wound therapy as they apply to the treatment of soft tissue defects of the hand. The indications, contraindications, and relative advantages and disadvantages of these techniques are discussed in detail.

Wound Healing Society (WHS) venous ulcer treatment guidelines: what's new in five years?

Since the establishment of the guidelines for the treatment of venous ulcers by the Wound Healing Society in 2006, there has been an abundance of new literature, both in accord and discord with the guidelines. The goal of this update is to highlight new findings since the publication of these guidelines to assist practitioner and patient in appropriate health care decisions, as well as to drive future research endeavors.

Negative pressure wound therapy for at-risk surgical closures in patients with multiple comorbidities: a prospective randomized controlled study

PURPOSE

The purpose of this study is to evaluate the effect of Negative Pressure Wound Therapy (NPWT) on closed surgical incisions. We performed a prospective randomized controlled clinical trial comparing NPWT to standard dry dressings on surgical incisions.

METHODS

Patients presenting to a high-volume wound center were randomized to receive either a V.A.C. (KCI, San Antonio, TX) or a standard dry dressing over their incision at the conclusion of surgery. These were primarily high-risk patients with multiple comorbidities. The 2 groups were compared, and all incisions were evaluated for infection and dehiscence postoperatively.

RESULTS

Eighty-one patients were included for analysis. Thirty-seven received dry dressings, and 44 received NPWT. Seventy-four of these underwent lower extremity wound closure. Average follow-up was 113 days. There were no differences in demographic, preoperative, and operative variables between groups; 6.8% of the NPWT group and 13.5% of the dry dressing group developed wound infection, but this was not statistically significant (P = 0.46). There was no difference in time to develop infection between the groups. There was no statistical difference in dehiscence between NPWT and dry dressing group (36.4% vs 29.7%; P = 0.54) or mean time to dehiscence between the 2 groups (P = 0.45). Overall, 35% of the dry dressing group and 40% of the NPWT group had a wound infection, dehiscence, or both. Of these, 9 in the NPWT group (21%) and 8 in the dry dressing group (22%) required reoperation.

CONCLUSIONS

There is a significant rate of postoperative infection and dehiscence in patients with multiple comorbidities. There was no difference in the incidence of infection or dehiscence between the NPWT and dry dressing group. This study is registered with ClinicalTrials.gov. The unique registration number is NCT01366105.

Negative pressure wound therapy for skin grafts and surgical wounds healing by primary intention

BACKGROUND

Indications for the use of negative pressure wound therapy (NPWT) are broadening with a range of systems on the market, including those designed for use on clean, closed incisions and skin grafts. Reviews have concluded that the evidence for the effectiveness of NPWT remains uncertain. However, this is a rapidly evolving therapy. Consequently, a systematic review of the evidence for the effects of NPWT on postoperative wounds expected to heal by primary intention is required.

OBJECTIVES

To assess the effects of NPWT on surgical wounds (primary closure or skin grafting) that are expected to heal by primary intention.

SEARCH METHODS

We searched the following electronic databases to identify reports of relevant randomised clinical trials: the Cochrane Wounds Group Specialised Register (searched 11 November 2011); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 4); Database of Abstracts of Reviews of Effects (The Cochrane Library 2011, Issue 4); Ovid MEDLINE (2005 to October Week 4 2011); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 8 November 2011); Ovid EMBASE (2009 to 2011 Week 44); and EBSCO CINAHL (1982 to 04 November 2011). We conducted a separate search to identify economic evaluations.

SELECTION CRITERIA

We included trials if they allocated patients at random and compared NPWT with any other type of wound dressing or compared one type of NPWT with a different type of NPWT.

DATA COLLECTION AND ANALYSIS

We assessed trials for their appropriateness for inclusion and for their quality. This was done by three review authors working independently, using pre-determined inclusion and quality criteria.

MAIN RESULTS

We included five eligible trials with a total of 280 participants. Two trials involved skin grafts and three acute wounds. Only one of the five trials reported the proportion of wounds completely healed and in this study all wounds healed. All five studies reported adverse events. In the four trials that compared standard dressings with negative pressure wound therapy (NPWT) the adverse event rate was similar between groups (negative pressure 33/86; standard dressing 37/103); risk ratio (RR) 0.97 (95% confidence intervals (CI) 0.33 to 2.89). There was significant heterogeneity for this result, due to the high incidence of fracture blisters in the NPWT group in one trial. One trial (87 participants) compared a commercial negative pressure device VAC® system with a negative pressure system developed in the hospital (GSUC). The adverse event rate was lower in the GSUC group (VAC® 3/42; GSUC 0/45); the RR was 0.13 (95% CI 0.01 to 2.51). Results indicate uncertainty about the true effect of either method on adverse events. The mean cost to supply equipment for VAC® therapy was USD 96.51/day compared to USD 4.22/day for the GSUC therapy (P = 0.01). Labour costs for dressing changes were similar. Pain intensity score was also reported to be lower in the GSUC group when compared with the VAC® group (p = 0.02)

AUTHORS' CONCLUSIONS

Evidence for the effectiveness of NPWT on complete healing of wounds expected to heal by primary intention remains unclear. Rates of graft loss may be lower when NPWT is used; but evidence to date suggests that hospital-based products are as effective in this area as commercial applications. There are clear cost benefits when non-commercial systems are used to create the negative pressure required for wound therapy, with no reduction in clinical outcome. Pain levels are also rated lower when hospital systems are compared with their commercial counterparts. The high incidence of blisters occurring when NPWT is used following orthopaedic surgery suggests that the therapy should be limited until safety in this population is established. Given the cost and widespread use of NPWT, there is an urgent need for suitably powered, high-quality trials to evaluate the effects of the newer NPWT products that are designed for use on clean, closed surgical incisions. Such trials should focus initially on wounds that may be difficult to heal, such as sternal wounds or surgeries for obese patients.

Vacuum-assisted closure improves the incorporation of artificial dermis in soft tissue defects: Terudermis(®) and Pelnac(®)

As a dermal scaffold, artificial dermal substitutes allow the body to accomplish its own tissue regeneration through infiltration of cells and neovascularisation. However, they show not only rather lower take rates compared to autologous skin grafts alone, but they also require more time for sufficient vascular ingrowth to overlay the skin graft. To accelerate this overlaying, we applied vacuum-assisted closure negative-pressure settings over the artificial dermis: Terudermis(®) and Pelnac(®) grafts. Fourteen patients with complex tissue defects were treated, including bone exposure in two cases, tendon exposure in seven cases and soft tissue defects in five cases. Nine cases had combined wound infections. The time interval between the first artificial dermis graft and the second split-thickness skin graft over it was 7·64 days on average. Dermal substitutes took place completely in all cases and there were no graft failures.

Evidence-based recommendations for the use of Negative Pressure Wound Therapy in traumatic wounds and reconstructive surgery: steps towards an international consensus

Negative pressure wound therapy (NPWT) has become widely adopted over the last 15 years and over 1000 peer reviewed publications are available describing its use. Despite this, there remains uncertainty regarding several aspects of usage. In order to respond to this gap a global expert panel was convened to develop evidence-based recommendations describing the use of NPWT. In this paper the results of the study of evidence in traumatic wounds (including soft tissue defects, open fractures and burns) and reconstructive procedures (including flaps and grafts) are reported. Evidence-based recommendations were obtained by a systematic review of the literature, grading of evidence, drafting of the recommendations by a global expert panel, followed by a formal consultative consensus development program in which 422 independent healthcare professionals were able to agree or disagree with the recommendations. The criteria for agreement were set at 80% approval. Evidence and recommendations were graded according to the SIGN (Scottish Intercollegiate Guidelines Network) classification system. Twelve recommendations were developed in total; 4 for soft tissue trauma and open fracture injuries, 1 for burn injuries, 3 for flaps and 4 for skin grafts. The present evidence base is strongest for the use of NPWT on skin grafts and weakest as a primary treatment for burns. In the consultative process, 11/12 of the proposed recommendations reached the 80% agreement threshold. The development of evidence-based recommendations for NPWT with direct validation from a large group of practicing clinicians offers a broader basis for consensus than work by an expert panel alone.

The effect and safety after extended use of continuous negative pressure of 75 mmHg over mesh and allodermis graft on open sternal wound from oversized heart transplant in a 3-month-old infant

Negative pressure therapy (NPT) has been reported to be effective in treating infants with open chest wounds. This report further supports its effectiveness by treating a 3-month-old infant with a 12 × 7 cm sized opening in its chest after an oversized heart transplantation. After applying a mesh and allodermis over the defect, 75-mmHg continuous negative pressure was set and used for an extended period of 104 days. The haemodynamic status was evaluated during this period. The wound was closed with secondary intention and it healed well after NPT. There was no haemodynamic instability during the treatment course. The extended use of a continuous negative pressure of 75 mmHg over the mesh and alloderm graft was a reliable and safe option to close the massive defect in the chest of a 3-month-old infant.

The use of negative pressure wound therapy for random local flaps at the ankle region

Local random flaps are seldom used for reconstruction of complex ankle wounds because of concern for flap failure attributable to vascular compromise and tissue edema. Negative pressure wound therapy has been shown to improve perfusion and limit tissue edema. The objective of this study was to demonstrate the utility of negative pressure wound therapy in improving outcomes for local flaps of the ankle. Ten consecutive patients presenting with complex ankle wounds and reconstructed using local flaps were treated with negative pressure wound therapy postoperatively. Type of flap, immediate and long-term outcomes, and complications were assessed. Seventeen local flaps were performed on 10 patients to reconstruct their ankle wounds. Mean follow up was 88 days. All flaps healed without tissue compromise or necrosis. Only one partial dehiscence and no infections were observed. This study demonstrates that negative pressure therapy may contribute to the viability of random local flaps by decreasing venous congestion. Our experience using negative pressure wound therapy on local flaps suggests that it may serve as a useful adjunct to ensure successful closure of high-risk wounds.

Fix and flap in the era of vacuum suction devices: What do we know in terms of evidence based medicine?

INTRODUCTION

The concept of immediate or early fixation and soft tissue coverage of open fractures is frequently referred to as 'fix and flap,' and negative pressure wound therapy (NPWT) has had a major impact in this area. This article aims to review concepts and evidence relevant to the use of NPWT in open fractures.

REVIEW OF OPEN FRACTURE MANAGEMENT

Muscle flaps in open fractures do well in part because they improve blood supply to the underlying fracture. Outcomes of muscle flaps are best when done acutely, before bacterial colonisation. The colonised subacute wound is managed with 'open-wound techniques' until it becomes a chronic localised wound, when flap coverage is again indicated. NPWT provides a useful adjunct in this process as the zone of injury is determined. VACUUM-ASSISTED CLOSURE: REVIEW OF BASIC AND CLINICAL SCIENCE LITERATURE: Proposed mechanisms of action of NPWT include: increased blood flow, decreased oedema, cytokine release induced by mechanical stretch and increased lactate and oxygen tension in the tissue with induction of collagen transcription and angiogenesis. VACUUM-ASSISTED CLOSURE IN OPEN FRACTURES: NPWT to open fractures caused early appearance of healthy granulation tissue, a reduction in wound area and allowed simpler soft tissue procedures for wound closure. NPWT also improved clinical survival of muscle flaps despite occluded flap venous outflow.

SUMMARY

The aim in open fractures is to stabilize the fracture and achieve soft tissue coverage before infection develops. NPWT, applied as a temporizing dressing, simplifies soft tissue coverage on the 'reconstructive ladder.' The only Level-I data on that topic showed a significant decrease in infections. However, NPWT does not allow delay in soft tissue coverage. NPWT increases the 'take rate' of skin grafts, skin substitutes and composite skin grafts and allows quicker graft incorporation.

An overview of negative pressure wound therapy for the lower extremity

Since its introduction into the market, negative pressure wound therapy (NPWT), also known as topical negative pressure, has become an important adjuvant therapy for the treatment of many types of wounds. Surgeons and physicians of all subspecialties have adopted NPWT into their practices. NPWT has become a mainstay in the management of lower extremity soft tissue pathology, especially in patients with traumatic, diabetic, postsurgical, and peripheral vascular disease-associated wounds. This article reviews the background, currently understood mechanisms of action, applications, contraindications, reported complications, advantages, criticisms, and techniques in the lower extremity.

Adult burn patients with more than 60% TBSA involved-Meek and other techniques to overcome restricted skin harvest availability--the Viennese Concept

Despite the fact that early excision and grafting has significantly improved outcome over the last decades, the management of severely burned adult patients with >/=60% total body surface area (% TBSA) burned still represents a challenging task for burn care specialists all over the world. In this article, we present our current treatment concept for this entity of severely burned patients and analyze its effect in a comparative cohort study. Surgical strategy comprised the use of split-thickness skin grafts (Meek, mesh) for permanent coverage, fluidized microsphere bead-beds for wound conditioning, temporary coverage (polyurethane sheets, Epigard; nanocrystalline silver dressings, Acticoat; synthetic copolymer sheets based on lactic acid, Suprathel; acellular bovine derived collagen matrices, Matriderm; allogeneic cultured keratinocyte sheets; and allogeneic split-thickness skin grafts), and negative-pressure wound therapy (vacuum-assisted closure). The autologous split-thickness skin graft expansion using the Meek technique for full-thickness burns and the delayed approach for treating dorsal burn wounds is discussed in detail. To demonstrate differences before and after the introduction of the Meek technique, we have compared patients of 2007 with >/=60% TBSA (n = 10) to those in a matched observation period (n = 7). In the first part of the comparative analysis, all patients of the two samples were analyzed with regard to age, abbreviated burn severity index, Baux, different entities of % TBSA, and survival. In the second step, only the survivors of both years were separated in two groups as follows: patients receiving skin grafts, using the Meek technique (n = 6), were compared with those without Meek grafting (n = 4). When comparing the severely burned patients of 2007 with a cohort of 2006, there were no differences for age (2007: 46.4 +/- 13.4 vs. 2006: 39.1 +/- 14.8 years), abbreviated burn severity index score (2007: 12.2 +/- 1.0 vs. 2006: 12.1 +/- 1.2) or % TBSA (2007: 72.1 +/- 11.7 vs. 2006: 69.3 +/- 8.7% TBSA). In these two rather small groups of severely burned patients with >/=60% TBSA, the overall survival rate of patients was 70.0% (7/10) in 2007 and 42.9% (3/7) in 2006, respectively. Almost all nonsurvivors in both years died within the first 5 days after admission. If assessing the different treatment modalities of the survivors, we found that although the Meek group patients were older (Meek 48.8 +/- 13.3 vs. non-Meek 26.8 +/- 11.5 years, P = .0381) and had consequently higher Baux scores (Meek 124.0 +/- 2.9 vs. non-Meek 93.8 +/- 8.5, P = .0095) than the non-Meek patients, this seemed to have no effect on length-of-stay (80.5 +/- 9.7 vs. non-Meek 79.8 +/- 33.0 days), hospital length-of-stay (85.7 +/- 14.8 vs. non-meek 84.3 +/- 26.1 days) or number of operations (6.5 +/- 1.0 vs. non-Meek 7.0 +/- 4.1 operations). The achieved results represent a combination of various treatment changes and, therefore, cannot be attributed to a single modality. The Meek technique is one of the technical options to choose from, to achieve permanent skin replacement; we think that it has its place if integrated in a whole treatment concept for management of severely burned patients.

Giant VAC in a patient with extensive necrotizing fasciitis

The authors present a case of an extensive fulminant necrotizing fasciitis of the left flank, thigh, and lower parts of the leg treated with debridement, split-thickness skin grafting, and a giant negative pressure wound dressing covering 0.53 m( 2) or 18% of the body surface. To the authors' knowledge, this is the largest split-thickness grafted body surface successfully treated with negative pressure wound dressing documented in the literature.

Negative pressure wound therapy with reticulated open cell foam-adjunctive treatment in the management of traumatic wounds of the leg: a review of the literature

Over the last decade, the application of and indications for negative pressure wound therapy with reticulated open cell foam (NPWT/ROCF) as delivered by V.A.C.(R) Therapy (KCI, San Antonio, TX) have grown tremendously. This is particularly true in orthopaedic trauma in the management of injuries to the leg, ankle, and foot. This article reviews the evidence-based medicine in terms of NPWT/ROCF, as a method of reducing bacterial counts in wounds, as a bridge until definitive bony coverage, for treating infections, and as an adjunct to wound bed preparation and for bolstering split-thickness skin grafts, dermal replacement grafts, and over muscle flaps. NPWT/ROCF has been shown to be an adjunct to the mainstays of wound management. No significant complications have been noted in the categories of NPWT/ROCF discussed in this review. In addition, evidence supports a decrease in complex soft tissue procedures in grade IIIB open fractures when NPWT/ROCF is employed. Although more research needs to be done, NPWT/ROCF appears to provide clinical benefit for the treatment of these complex lower extremity wounds.