Negative pressure therapy: theory and practice

Management of Postoperative Pancreatic Fistulas After Pancreaticoduodenectomy Using Open Drainage and Negative Pressure Wound Therapy With Instillation and Dwell Times

Introduction Postoperative pancreatic fistula (POPF) is a common complication of pancreatoduodenectomy (PD) that may cause lethal complications. Therefore, it is important to properly treat POPF and prevent its aggravation during the postoperative management of PD. We have used a combination of open drainage, in which the wound above the fluid collection is opened, and negative pressure wound therapy with instillation and dwell time (NPWTi-d) to manage POPF after PD. To evaluate the feasibility and efficacy of this combination treatment, we analyzed the outcomes of patients with POPF after PD. Methods Patients who underwent PD were reviewed and those who developed POPF were extracted and divided into three groups according to the management of POPF: N group (patients treated with open drainage and NPWTi-d), O group (patients treated with open drainage without NPWTi-d), and C group (patients treated with catheter drainage). The perioperative outcomes were compared among the three groups. Results During the study period, 133 patients underwent PD, out of which 39 (29%) developed POPF (≥grade B). Among the 39 patients with POPF, eight, four, and 27 were classified into the N, O, and C group, respectively. No mortality was observed in the patients with POPF. No severe complications were observed in the patients who underwent open drainage (N and O groups), while two patients in the C group developed severe complications. Among the patients who underwent open drainage, the N group tended to have a shorter postoperative hospital stay than the O group. Conclusions The current study suggests that open drainage safely and effectively healed POPF and NPWTi-d promoted wound closure. The combination of open drainage and NPWTi-d may prevent the aggravation of POPF, reduce failure to rescue, and shorten hospital stay after PD.

Engineered Extracellular Vesicles in Wound Healing: Design, Paradigms, and Clinical Application

The severe quality of life and economic burden imposed by non-healing skin wounds, infection risks, and treatment costs are affecting millions of patients worldwide. To mitigate these challenges, scientists are relentlessly seeking effective treatment measures. In recent years, extracellular vesicles (EVs) have emerged as a promising cell-free therapy strategy, attracting extensive attention from researchers. EVs mediate intercellular communication, possessing excellent biocompatibility and stability. These features make EVs a potential tool for treating a plethora of diseases, including those related to wound repair. However, there is a growing focus on the engineering of EVs to overcome inherent limitations such as low production, relatively fixed content, and targeting capabilities of natural EVs. This engineering could improve both the effectiveness and specificity of EVs in wound repair treatments. In light of this, the present review will introduce the latest progress in the design methods and experimental paradigms of engineered EVs applied in wound repair. Furthermore, it will comprehensively analyze the current clinical research status and prospects of engineered EVs within this field.

Efficacy of one-hour negative pressure wound therapy and magnetic field energy in wound healing

OBJECTIVE

Wound healing is an important aspect of health but needs further research to identify the effects and interactions of different treatment approaches on healing. The aims of this study were to investigate the effectiveness of one-hour negative pressure wound therapy (NPWT) and compare histological differences between one-hour NPWT and magnetic field energy (MFE) in rats on early-stage wound healing, wound size and angiogenesis.

METHOD

Standardised wounds were created on Wistar rats that were allocated and divided into NPWT, MFE and control groups. Both treatments were applied for 1 hour/day for 10 days. Wound size, histological changes and wound area blood flow were assessed.

RESULTS

The wound size of all groups was similar on days 0, 2 and 10. The MFE group's wound size was smaller than the NPWT group on days 4, 6 and 8 (p<0.05). Development of the granulation tissue in both the one-hour NPWT and MFE groups was greater than in the control group. Additionally, the inflammatory phase was shorter, and wounds entered the proliferative stage faster in the MFE group than both of the other groups.

CONCLUSION

Treatment with MFE may be more effective in terms of early stage wound closure and angiogenesis. On the other hand, the NPWT group's wound area blood flow was significantly greater than the other two groups. MFE is superior to one-hour NPWT in terms of wound area and angiogenesis. Furthermore, it is worthwhile to note that one-hour NPWT increases bloodflow in the wound area, which stimulates healing.

Physical therapy in diabetic foot ulcer: Research progress and clinical application

Diabetes foot ulcer (DFU) is one of the most intractable complications of diabetes and is related to a number of risk factors. DFU therapy is difficult and involves long-term interdisciplinary collaboration, causing patients physical and emotional pain and increasing medical costs. With a rising number of diabetes patients, it is vital to figure out the causes and treatment techniques of DFU in a precise and complete manner, which will assist alleviate patients' suffering and decrease excessive medical expenditure. Here, we summarised the characteristics and progress of the physical therapy methods for the DFU, emphasised the important role of appropriate exercise and nutritional supplementation in the treatment of DFU, and discussed the application prospects of non-traditional physical therapy such as electrical stimulation (ES), and photobiomodulation therapy (PBMT) in the treatment of DFU based on clinical experimental records in ClinicalTrials.gov.

Role of wound microbiome, strategies of microbiota delivery system and clinical management

Delayed wound healing is one of the most global public health threats affecting nearly 100 million people each year, particularly the chronic wounds. Many confounding factors such as aging, diabetic disease, medication, peripheral neuropathy, immunocompromises or arterial and venous insufficiency hyperglycaemia are considered to inhibit wound healing. Therapeutic approaches for slow wound healing include anti-infection, debridement and the use of various wound dressings. However, the current clinical outcomes are still unsatisfied. In this review, we discuss the role of skin and wound commensal microbiota in the different healing stages, including inflammation, cell proliferation, re-epithelialization and remodelling phase, followed by multiple immune cell responses to commensal microbiota. Current clinical management in treating surgical wounds and chronic wounds was also reviewed together with potential controlled delivery systems which may be utilized in the future for the topical administration of probiotics and microbiomes. This review aims to introduce advances, novel strategies, and pioneer ideas in regulating the wound microbiome and the design of controlled delivery systems.

The use of Indonesian randu honey for chronic wounds in a patient with uncontrolled type 2 diabetes mellitus: A case report

Introduction and importance

Honey has been recorded as having healing properties at a low cost. Many studies have been conducted related to Manuka honey, but studies about Indonesian randu honey are still limited. We report the use of Indonesian randu honey as a wound dressing on non-pressure chronic skin ulcers in uncontrolled T2DM patient.

Case presentation

A 54-year-old man with uncontrolled T2DM came with an unrecovered wound. A thorough inspection revealed several exposed bones, tendons, muscles, and meniscus in the left lower leg region. It was supposed to be amputated, but he declined. He received insulin, debridement, STSG, and a combination of Indonesian randu honey dressing and VAC on the exposed wound before and after the debridement and STSG. There was skin graft lysis, and we intended to do another surgery, but he preferred to be an outpatient. As an outpatient, he received honey wound dressing and insulin. After 1.5 years, the wound was fully closed, and he could walk with the help of a walking stick.

Clinical discussion

Treatment for multiple exposed bones, tendons, and muscles in uncontrolled T2DM patient are complex. Studies reported that Indonesian honey could provide an antibacterial effect, cost-efficiency, speed up wound healing with no side effects, and no physical-chemical properties differences compared to Manuka honey.

Conclusion

Using Indonesian randu honey as wound dressing could stimulate wound healing with no side effects in chronic wounds with uncontrolled T2DM that were supposed to be amputated. However, it took several months for the wound to fully close.

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Honey has been recorded as having healing properties since ancient times.

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Indonesian randu honey can stimulate wound healing in chronic wounds with uncontrolled T2DM that had to be amputated.

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There were no allergic reactions or secondary infections related to the application of Indonesian randu honey.

Prophylactic negative pressure wound therapy on wound complications after cesarean delivery in women with obesity: a meta-analysis of randomized controlled trials

OBJECTIVE

This systematic review and meta-analysis of randomized controlled trials aimed to assess whether negative pressure wound therapy affects the rate of wound complications when applied to women with obesity after cesarean delivery compared with standard postoperative dressings.

DATA SOURCES

This research used PubMed, Scopus, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials as electronic databases, from the inception of each database to January 2021, with randomized controlled trial as the publication type. There was no restriction applied for language or geographic location.

STUDY ELIGIBILITY CRITERIA

The selection criteria included only randomized controlled trials comparing the effect of negative pressure wound therapy with that of standard dressings on wound complications in women with obesity undergoing cesarean delivery.

METHODS

The primary outcome was a wound complication composite outcome (wound infection, separation or dehiscence, hematoma, seroma, or readmission secondary to a wound concern). The wound complication composite was analyzed by counting events once per patient. The summary measures were reported as relative risk or as mean difference with 95% confidence intervals using the random-effects model of DerSimonian and Laird. An I-squared (Higgins I²) value of >0% was used to identify heterogeneity.

RESULTS

Overall, 11 randomized controlled trials, which included 5746 participants with obesity undergoing cesarean delivery, were included. Of those participants, 2869 (49.9%) were randomized to the intervention group (negative pressure wound therapy), and 2877 (50.1%) were randomized to the control group (standard dressing). Prophylactic negative pressure wound therapy was not associated with a significant change in the rate of wound complications (relative risk, 1.00; 95% confidence interval, 0.81-1.23) compared with standard postoperative dressings. However, the use of negative pressure wound therapy decreased the rate of wound infections (relative risk, 0.79; 95% confidence interval, 0.66- 0.96) and increased the frequency of skin reactions (relative risk, 4.59; 95% confidence interval, 1.29-16.38). Negative pressure wound therapy did not result in a significant difference in the rate of dehiscence, hematoma, seroma, readmission, reoperation, and antibiotic use for wound infection.

CONCLUSION

Compared with standard postoperative incision dressings, negative pressure wound therapy did not affect the rate of wound complications but decreased the frequency of wound infections when applied to women with obesity after cesarean delivery. However, results should be interpreted with caution, as wound infection outcome includes different definitions per the individual trials.

CONDENSATION

Prophylactic negative pressure wound therapy has no effect on overall wound complications in women with obesity after cesarean delivery compared with standard dressings.

Proteomics changes after negative pressure wound therapy in diabetic foot ulcers

Label-free quantitative mass spectrometry was used to analyze the differences in the granulation tissue protein expression profiles of patients with diabetic foot ulcers (DFUs) before and after negative-pressure wound therapy (NPWT) to understand how NPWT promotes the healing of diabetic foot wounds. A total of three patients with DFUs hospitalized for Wagner grade 3 were enrolled. The patients received NPWT for one week. The granulation tissue samples of the patients prior to and following NPWT for one week were collected. The protein expression profiles were analyzed with label-free quantitative mass spectrometry and the differentially expressed proteins (DEPs) in the DFU patients prior to and following NPWT for one week were identified. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were conducted to annotate the DEPs and DEP-associated signaling pathways. Western blotting and ELISA were performed to validate the results. By comparing the differences in the protein profiles of granulation tissue samples prior to and following NPWT for one week, 36 proteins with significant differences were identified (P<0.05); 33 of these proteins were upregulated and three proteins were downregulated. NPWT altered proteins mainly associated with antioxidation and detoxification, the cytoskeleton, regulation of the inflammatory response, complement and coagulation cascades and lipid metabolism. The functional validation of the DEPs demonstrated that the levels of cathepsin S in peripheral blood and granulation tissue were significantly lower than those prior to NPWT (P<0.05), while the levels of protein S isoform 1, inter α-trypsin inhibitor heavy chain H4 and peroxiredoxin-2 in peripheral blood and granulation tissue were significantly higher than those prior to NPWT (P<0.05). The present study identified multiple novel proteins altered by NPWT and laid a foundation for further studies investigating the mechanism of action of NPWT.

Consensus on the application of negative pressure wound therapy of diabetic foot wounds

Because China is becoming an aging society, the incidence of diabetes and diabetic foot have been increasing. Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates. Negative pressure wound therapy (NPWT) is one of the most effective techniques for the treatment of diabetic foot wounds and great progress, both in terms of research and its clinical application, has been made in the last 20 years of its development. However, due to the complex pathogenesis and management of diabetic foot, irregular application of NPWT often leads to complications, such as infection, bleeding and necrosis, that seriously affect its treatment outcomes. In 2020, under the leadership of Burns, Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association, the writing group for ‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’ was established with the participation of scholars from the specialized areas of burns, endocrinology, vascular surgery, orthopedics and wound repair. Drawing on evidence-based practice suggested by the latest clinical research, this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot. The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.

Esophageal Perforation and EVAC in Pediatric Patients: A Case Series of Four Children

Introduction: In pediatric patients, esophageal perforation (EP) is rare but associated with significant morbidity and mortality rates of up to 20-30%. In addition to standard treatment options, endoscopic esophageal vacuum-assisted closure (EVAC) therapy has shown promising results, especially in adult patients. Thus far, the only data on technical success and effectiveness of EVAC in pediatric patients were published in 2018 by Manfredi et al. at Boston Children's Hospital. The sparse data on EVAC in children indicates that this promising technique has been barely utilized in pediatric patients. More data are needed to evaluate efficacy and outcomes of this technique in pediatric patients. Method: We reviewed five cases of therapy using EVAC, ArgyleTM Replogle Suction Catheter (RSC), or both on pediatric patients with EP in our institution between October 2018 and April 2020. Results: Five patients with EP (median 3.4 years; 2 males) were treated with EVAC, RSC, or a combination. Complete closure of EP was not achieved after EVAC alone, though patients' health stabilized and inflammation and size of EP decreased after EVAC. Four patients then were treated with RSC until the EP healed. One patient needed surgery as the recurrent fistula did not heal sufficiently after 3 weeks of EVAC therapy. Two patients developed stenosis and were successfully treated with dilatations. One patient treated with RSC alone showed persistent EP after 5 weeks. Conclusion: EVAC in pediatric patients is technically feasible and a promising method to treat EP, regardless of the underlying cause. EVAC therapy can be terminated as soon as local inflammation and C-reactive protein levels decrease, even if the mucosa is not healed completely at that time. A promising subsequent treatment is RSC. An earlier switch to RSC can substantially reduce the need of anesthesia during subsequent treatments. Our findings indicate that EVAC is more effective than RSC alone. In some cases, EVAC can be used to improve the tissues condition in preparation for a re-do surgery. At 1 year after therapy, all but one patient demonstrated sufficient weight gain. Further prospective studies with a larger cohort are required to confirm our observations from this small case series.

[Complex treatment of patients with pyo-necrotic complications of the neuropathic form of diabetic foot syndrome]

OBJECTIVE

Of study is improving the results of treatment of patients with pyo-necrotic complications of diabetic foot syndrome by including the method of negative pressure wound treatment in the complex treatment program in combination with using of the combined antibacterial drug Cifran ST and immunocorrective therapy.

MATERIAL AND METHODS

The results of examination and treatment of 184 patients with pyo-necrotic complications of the neuropathic form of diabetic foot syndrome were analyzed. According to choice of treatment methods in the postoperative period all patients were divided into two groups. In 95 patients (group I), iodine-containing ointments based on polyethylene glycol were used for local treatment of purulent foot wounds and standard systemic antibacterial therapy was performed. In 89 patients (group II), negative pressure wound treatment (NPWT) was used to treat wounds in the postoperative period. In addition to standard parenteral antimicrobial therapy, these patients also received an oral combined antibacterial drug Cifran ST and immunocorrective cytokine therapy (Leukinferon). The analysis of the dynamics of the wound process was carried out based on the clinical picture and the results of cytological, bacteriological and immunological studies of the wound exudate.

RESULTS

The presented strategy of complex treatment of pyo-necrotic complications of the neuropathic form of diabetic foot syndrome allowed group II patients to significantly reduce the degree of microbial contamination of wounds, to achieve a faster regression of the content of proinflammatory and inflammatory cytokines in the wound exudate, as well as to reduce the time of wound cleansing and the transition of the pyo-necrotic process to the reparative stage in comparison with group I patients. This allowed group II patients to reduce the time of plastic closure of the wound from 24.3±0.5 to 15.6±1.7 days, to avoid generalization of infection, death and high level amputation of the limb. At the same time, 11.6% of patients in group I had high level limb amputation due to generalization of infection. The mortality rate in group I was 5.3%.

CONCLUSIONS

Adding of vacuum therapy of wounds, systemic antimicrobial therapy using the combined antibacterial drug Cifran ST and immunocorrective cytokine therapy in the complex treatment program for patients with neuropathic form of diabetic foot syndrome after radical surgical treatment of the pyo-necrotic lesion allows reducing the time of wound cleansing and the transition of the pyo-necrotic process to the reparative stage. On the other hand, this makes it possible for this category of patients to perform plastic closure of the wound at an earlier date, avoid generalization of infection and high level amputation of the limb.

Negative-Pressure Wound Therapy in Foot and Ankle Surgery

Negative Pressure Wound Therapy (NPWT) is frequently utilized to manage complex wounds, however its mechanisms of healing remain poorly understood. Changes in growth factor expression, micro- and macro-deformation, blood flow, exudate removal, and bacterial concentration within the wound bed are thought to play a role. NPWT is gaining widespread usage in foot and ankle surgery, including the management of traumatic wounds; diabetic and neuropathic ulcers; wounds left open after debridement for infection or dehiscence; high-risk, closed incisions; tissue grafts and free flaps. This article reviews the rationale for NPWT, its proposed mechanisms of action, and the evidence regarding its clinical applications within the field of foot and ankle surgery. Level of Evidence: Level V, expert opinion.

Prophylactic negative pressure wound therapy for surgical site infection in obese women undergoing cesarean section: an evidence synthesis with trial sequential analysis

OBJECTIVE

Current evidence for negative pressure wound therapy (NPWT) on surgical site infection (SSI) and wound complications in cesarean section is conflicting. The objective of this study was to evaluate the efficacy of prophylactic NPWT for preventing SSI and other wound complications in obese women undergoing cesarean section (CS).

METHODS

We systematically searched PubMed, Embase, the Cochrane Library and clinicaltTrial.gov to identify randomized controlled trials (RCTs) that compared NPWT with standard dressing for cesarean section. The primary outcome was SSI. Secondary outcomes were overall wound complications and hospital readmission. Risk ratio (RR) with 95% confidence intervals (CIs) was calculated using random-effects models. Review Manager 5.3 was applied to analyze the collected data.

RESULTS

Eight RCTs involving 1972 patients were included in this meta-analysis. The pooled results showed that the risk of SSI was significantly lower with the use of NPWT when compared with standard dressing (RR = 0.68, 95%CI = 0.51-0.90, p = .008). However, there was no difference in overall wound complications (RR = 0.93, 95%CI = 0.74-1.17, p = 0.52) and hospital readmission (RR = 1.03, 95%CI = 0.67-1.60, p = .89) between two groups. Current evidence was not confirmed by trial sequential analysis.

CONCLUSION

On the basis of our findings, NPWT decreases the risk of SSI after cesarean section in obese women after CS, despite this approach does not reduce the overall wound complications and hospital readmission. However, further RCTs are needed to make conclusive evidence.

Negative pressure wound therapy promoted wound healing by suppressing inflammation via down-regulating MAPK-JNK signaling pathway in diabetic foot patients

AIMS

Negative pressure wound therapy displayed significant clinical benefits in the healing of diabetic foot wounds. In the present study, we investigated the mechanism of regulation of MAPK-JNK (Mitogen-activated protein kinase- c-Jun N-terminal kinase) signaling pathway by negative pressure wound therapy on these wounds.

METHODS

Twenty-six type 2 diabetes patients with foot ulceration were randomly assigned to the two groups, thirteen treated with negative pressure wound therapy and the others treated with traditional debridement therapy. Skin samples were harvested and histologically and immunohistochemical analyzed in both groups. Immunofluorescence stain, Enzyme-linked immunosorbent assay and Western blotting were performed for inducible nitric oxide synthase, inter leukin-6, tumor necrosis factor-α, P-c-Jun N-terminal kinase and c-Jun N-terminal kinase. Real time-polymerase chain reaction was performed to evaluate expression of c-Jun N-terminal kinase, extracellular signal regulated kinase1/2 and p38.

RESULTS

Negative pressure wound therapy could effectively alleviate inflammatory reaction and reduce inter leukin-6 and inducible nitric oxide synthase production after 7 days treatment. The level of tumor necrosis factor-α, inter leukin-6 and P-c-Jun N-terminal kinase were significantly decreased. However, there was no statistical difference in messenger ribonucleic acid expression of p38, extracellular signal regulated kinase1 and 2.

CONCLUSIONS

Negative pressure wound therapy possibly suppress the wound inflammation by inhibiting inter leukin-6, tumor necrosis factor-α and inducible nitric oxide synthase in diabetic foot patients. This effect is maybe mediated at least in part by suppression of Mitogen-activated protein kinase- c-Jun N-terminal kinase signaling pathway.

Effect of negative-pressure wound therapy on the circulating number of peripheral endothelial progenitor cells in diabetic patients with mild to moderate degrees of ischaemic foot ulcer

Objective

To investigate the effect of negative-pressure wound therapy (NPWT) on the circulating number of endothelial progenitor cells (EPCs) in diabetic patients with mild to moderate degrees of ischemic foot ulcer.

Methods

We selected 84 diabetic patients who had a foot ulcer with a duration of at least four weeks and who had an ankle-brachial index of 0.5–0.9. Patients were assigned to one two groups according to 2:1 randomization: NPWT group ( n = 56) and non-NPWT (patients who did not receive NPWT) group ( n = 28). The control group (NC group) was composed of 18 patients who had normal glucose tolerance and lower extremity ulcer without arteriovenous disease. NPWT was performed on the ulcer after debridement for one week for patients in both the NPWT group and the NC group, and the patients in the non-NPWT group received conventional treatment process. The circulating number of EPCs was measured before and after various treatments, and the factors influencing their changes were analysed.

Results

After NPWT, the circulating number of EPCs significantly increased in both the NPWT group and the NC group ((85.3 ± 18.1) vs. (34.1 ± 12.5)/106 cells; (119.9 ± 14.4) vs. (66.1 ± 10.6)/106 cells, both P < 0.05). In contrast, the circulating number of EPCs had no significant change in the non-NPWT group ((45.2 ± 19.4) vs. (34.7 ± 16.8)/106 cells, P > 0.05). In addition, the circulating levels of vascular endothelial growth factor (VEGF) and the protein expressions of VEGF and stromal cell-derived factor-1α (SDF-1α) in the granulation tissue significantly increased after NPWT in both the NPWT and the NC group, but there was no significant change in the non-NPWT group. Compared with the non-NPWT group, the changes in VEGF and SDF-1α levels in the sera and granulation tissue were all significantly higher in both the NPWT and NC groups ( P < 0.05, P < 0.01, respectively). There was no significant difference in changes in the circulating number of EPCs in the peripheral blood and levels of VEGF and SDF-1α in the sera and granulation tissue between the NPWT and NC groups. Correlation analysis showed that the change in the circulating number of EPCs was correlated with the changes of VEGF and SDF-1α levels in the sera and granulation of the NPWT and NC groups ( P < 0.05).

Conclusion

NPWT may increase the circulating number of EPCs in diabetic patients with mild to moderate ischaemic foot ulcer as in non-diabetic controls, which may be attributed to the upregulation of systemic and local VEGF and SDF-1α levels.

* A Rodent Excision Model for Ischemia-Impaired Wound Healing

Delayed wound healing and the potentially resulting chronic wounds are a challenging clinical problem. Available therapeutic strategies are limited in both number and efficacy. For developing and establishing novel treatment approaches appropriate clinically relevant animal models are essential. The aim of the study was to establish a reliable and reproducible delayed wound healing model, which simulates the clinical scenario of compromised vascular tissue perfusion (hypoxia/ischemia). Therefore a standard rodent ischemic flap model was modified by challenging the tissue with ascending degrees of ischemia using different surgical approaches (minimal, mild, moderate, and severe ischemic invasive approach). Then a full-thickness circular wound was excised in both the non-/hypoperfused flap area and in the normally perfused contralateral region serving as an internal control. Wound healing progress was compared. Superficial tissue perfusion was measured by Laser Doppler imaging technique, which showed persistent ischemia in the moderate and severe invasive surgical approaches 7 days after wounding. Wound closure assessed by planimetric analysis occurred significantly slower in the ischemic wounds compared to the contralateral nonischemic wounds in the moderate invasive approach. Histologic evaluations in this approach showed signs of tissue necrosis and impaired angiogenesis in the ischemic wounds. Therefore, it can be concluded that this clinically relevant animal model is suitable to study mechanism in ischemia-impaired wound healing. Furthermore, it allows evaluating the efficacy of therapeutic strategies for impaired wound healing and comparing the results with an internal control wound.

Negative pressure wound treatment with computer-controlled irrigation/instillation decreases bacterial load in contaminated wounds and facilitates wound closure

Microbial wound contamination is known to be a hindrance to wound healing. Negative pressure wound therapy (NPWT) with or without irrigation is known to optimise conditions in problem wounds. The aim of this study was to investigate the influence of computer-controlled wound irrigation with NPWT on the bacterial load in contaminated wounds. A total of 267 patients were treated with NPWT with automated instillation because of problematic wounds using an antiseptic instillation solution. In 111 patients, a minimum of 4 operative procedures were necessary, and swabs were taken at least at the first and at the fourth operation in a standardised procedure. The number of different bacteria and the amount of bacteria were analysed during the course. In a subgroup of 51 patients, swabs were taken at all 4 operative procedures and analysed separately. In an overall analysis, the number of different bacteria and the amount of bacteria significantly decreased independent of wound localisation and diagnosis. NPWT with automated instillation demonstrates a positive influence in the reduction of bacterial load in problem wounds. Thus, it may help to optimise wound conditions before definite wound closure.

MODIFIED VAC DRESSING IN STERNAL WOUND INFECTION MANAGEMENT. CHEAP AND FEASIBLE TECHNIQUE IN DEVELOPING COUNTRY

Sternal wound infection is a rare but serious complication of cardiac surgery leading to prolonged hospital stay and higher mortality. In the last decades several treatment modalities have been described, of which vacuum-assisted closure (VAC) shows the most promising results. However, the VAC therapy system is expensive, requires extensive amounts of product and needs a power source at all times. Modified VAC dressing to treat sternal wound infection is cheap and feasible technique to use in develop country. This technique can be use as an alternative to the original vacuum-assisted closure and hadshown to serve its function in providing adequatevacuum pressure for wounds.

Effect of Negative Pressure Wound Therapy on Cellular Fibronectin and Transforming Growth Factor-β1 Expression in Diabetic Foot Wounds

BACKGROUND

Chronic diabetic foot wounds are a leading cause of amputation, morbidity, and hospitalization for patients with diabetes. Negative-pressure wound therapy (NPWT) can putatively facilitate wound healing, but the underlying mechanisms remain unclear. Cellular fibronectin (cFN) and transforming growth factor-β1 (TGF-β1) play an important role in wound healing. This prospective randomized controlled trial evaluated the effects of NPWT on the production of cFN and the expression of TGF-β1 in diabetic foot wounds of patients.

METHODS

From January 2012 to January 2015, 40 patients with diabetic foot wounds were randomly and equally apportioned to receive either NPWT or advanced moist wound therapy (control) for 7 days. Granulation tissue was harvested before and after treatment. Immunohistochemistry and Western blot were performed to evaluate protein levels of cFN and TGF-β1, and real-time polymerase chain reaction (PCR) to measure corresponding mRNA expressions.

RESULTS

NPWT facilitated the expression of cFN and TGF-β1 in diabetic foot wounds. Immunohistochemical analysis revealed higher levels of cFN and TGF-β1 in the NPWT group than in the control group. Western blot and real-time PCR analysis further showed that protein and mRNA levels of cFN or TGF-β1 were higher in the NPWT group than that in the control group ( P < .01, both).

CONCLUSION

Our results showed that NPWT facilitated the production of cFN and the expression of TGF-β1 in granulation tissue in diabetic foot ulcers.

LEVEL OF EVIDENCE

Level I, randomized controlled study.

Evaluation of negative-pressure wound therapy for patients with diabetic foot ulcers: systematic review and meta-analysis

Objectives

The aim of this study was to perform an updated systematic review and meta-analysis to assess the clinical efficacy, safety, and cost-effectiveness of negative-pressure wound therapy (NPWT) in the treatment of diabetic foot ulcers (DFUs).

Methods

We searched the Cochrane Library, MEDLINE, EMBASE, Ovid, and Chinese Biological Medicine databases up to June 30, 2016. We also manually searched the articles from reference lists of the retrieved articles, which used the NPWT system in studies of vacuum-assisted closure therapy. Studies were identified and selected, and two independent reviewers extracted data from the studies.

Results

A total of eleven randomized controlled trials, which included a total of 1,044 patients, were selected from 691 identified studies. Compared with standard dressing changes, NPWT had a higher rate of complete healing of ulcers (relative risk, 1.48; 95% confidence interval [CI]: 1.24–1.76; P<0.001), shorter healing time (mean difference, −8.07; 95% CI: −13.70– −2.45; P=0.005), greater reduction in ulcer area (mean difference, 12.18; 95% CI: 8.50–15.86; P<0.00001), greater reduction in ulcer depth (mean difference, 40.82; 95% CI: 35.97–45.67; P<0.00001), fewer amputations (relative risk, 0.31; 95% CI: 0.15–0.62; P=0.001), and no effect on the incidence of treatment-related adverse effects (relative risk, 1.12; 95% CI: 0.66–1.89; P=0.68). Meanwhile, many analyses showed that the NPWT was more cost-effective than standard dressing changes.

Conclusion

These results indicate that NPWT is efficacious, safe, and cost-effective in treating DFUs.

Circulating fibrocyte mobilization in negative pressure wound therapy

Non‐healing diabetic wounds are difficult to treat. They also create heavy financial burdens for both patients and society. Negative pressure wound therapy (NPWT) has been adopted to treat intractable wounds and has proved to be effective. However, the mechanisms that underlie the effects of this treatment are not entirely understood. Circulating fibrocytes are unique haematopoietic‐derived stem cells that have been reported to play a pivotal role in wound healing. Here, we have investigated the effect of NPWT on fibrocyte mobilization and the role of fibrocyte mobilization in the healing of diabetic wounds during NPWT. We show that the NPWT group exhibited 2.6‐fold to 12.1‐fold greater numbers of tail vein‐injected PKH‐26‐labelled fibrocytes in the diabetic wound sites compared with the control group. We also demonstrate that the full‐thickness skin wounds treated with NPWT exhibit significantly reduced mRNA and protein expression, blood vessel density and proliferating cells when exogenous fibrocyte mobilization is inhibited. We speculate that systemic mobilization of fibrocytes during NPWT may be a mechanism for healing intractable wounds in a diabetic rat model experiment and that enhancement of cell mobilization may represent a potential treatment idea for intractable wound healing across all fields of surgery.

Novel negative pressure wound therapy with instillation and the management of diabetic foot infections

PURPOSE OF REVIEW

The use of negative pressure wound therapy with instillation (NPWTi) in complex or difficult-to-treat acute and chronic wounds has expanded rapidly since the introduction of commercially available NPWTi systems. We summarize the evidence related to NPWTi and particularly focus on the application of this technology in diabetic foot ulcers, diabetic foot infections and postoperative diabetic wounds.

RECENT FINDINGS

The benefits of negative pressure wound therapy (NPWT) are well documented in the treatment of complex acute and chronic wounds, including noninfected postoperative diabetic wounds and diabetic foot ulcers. Combining intermittent wound irrigation with NPWT may offer additional benefits compared to NPWT alone, including further reduction of wound bed bioburden, increased granulation tissue formation and provision of wound irrigation in a sealed environment, thus preventing potential cross-contamination events. Recently, available evidence suggests that adjunctive NPWTi may be superior to standard NPWT in the management of diabetic infections following surgical debridement and may promote granulation tissue formation in slow-to-heal wounds.

SUMMARY

Available evidence relating to the utilization of NPWTi in diabetic foot infections is promising but limited in quality, being derived mostly from case series or small retrospective or prospective studies. In order to confirm or refute the potential benefits of NPWTi in this patient cohort, well designed randomized controlled studies are required that compare NPWTi to NPWT or standard wound care methodologies.

Innovation and wound healing

Innovation in medicine requires unique partnerships between academic research, biotech or pharmaceutical companies, and health-care providers. While innovation in medicine has greatly increased over the past 100 years, innovation in wound care has been slow, despite the fact that chronic wounds are a global health challenge where there is a need for technical, process and social innovation. While novel partnerships between research and the health-care system have been created, we still have much to learn about wound care and the wound-healing processes.

Negative-pressure wound therapy for the treatment of pharyngocutaneous fistula

INTRODUCTION

Pharyngocutaneous fistula is a well-known complication of head and neck cancer surgery.The purpose of this study was to determine the value of negative-pressure wound therapy (NPWT) for the treatment of these fistulas. NPWT is used in many fields of medicine, but its use in otorhinolaryngology has been rarely reported. NPWT is a cost-effective means to accelerate wound healing.

PATIENTS AND METHODS

A single-centre retrospective study was conducted on 7 patients with pharyngo-cutaneous fistula following surgery for squamous cell carcinoma between January 2011 and April 2013.These fistulas were treated by negative-pressure wound therapy (NPWT).

RESULTS

This series comprised seven male patients with a mean age of 65 years and 9 months. The mean duration of treatment was 23 days (range: 11 to 42 days). Two patients had a history of radiotherapy for pharyngolaryngeal cancer. Negative-pressure wound therapy achieved cure of the fistula in all patients with satisfactory acceptability. Mean follow-up was 10 months (range: 6 months to 2 years).

CONCLUSION

Negative-pressure wound therapy represents a valuable treatment option in certain settings for the management of pharyngocutaneous fistula following head and neck cancer surgery.

Negative pressure wound therapy technologies for chronic wound care in the home setting: A systematic review

The use of negative pressure wound therapy (NPWT) is increasing in both the inpatient and outpatient settings. We conducted a systematic review on the efficacy and safety of NPWT for the treatment of chronic wounds in the home setting. We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and the Cumulative Index to Nursing and Allied Health Literature, up to June 2014. Two independent reviewers screened search results. Seven studies met our criteria for inclusion. Six of the studies compared NPWT devices to other wound care methods and one study compared two different NPWT technologies. Data were limited by variability in the types of comparator groups, methodological limitations, and poor reporting of outcomes. We were unable to draw conclusions about the efficacy or safety of NPWT for the treatment of chronic wounds in the home setting due to the insufficient evidence. Consensus is needed on the methods of conducting and reporting wound care research so that future studies are able inform decisions about the use of NPWT in the home environment for chronic wounds.

Negative-pressure wound therapy for management of diabetic foot wounds: a review of the mechanism of action, clinical applications, and recent developments

Negative-pressure wound therapy (NPWT) plays an important role in the treatment of complex wounds. Its effect on limb salvage in the management of the diabetic foot is well described in the literature. However, a successful outcome in this subgroup of diabetic patients requires a multidisciplinary approach with careful patient selection, appropriate surgical debridement, targeted antibiotic therapy, and optimization of healing markers. Evolving NPWT technology including instillation therapy, nanocrystalline adjuncts, and portable systems can further improve results if used with correct indications. This review article summarizes current knowledge about the role of NPWT in the management of the diabetic foot and its mode of action, clinical applications, and recent developments.

Prologue: transformational healing solutions

In recent years, the provision of wound care for patients has dramatically improved through the development of new therapeutic options, allowing for a wide range of wound care therapy choices. In June 2014, an educational International Surgical Wound Forum (ISWF) was held to present current options in wound care to a multidisciplinary group of healthcare providers. Topics included negative pressure wound therapy with instillation and dwell time (NPWTi-d), surgical incision management (SIM), use of NPWT in the management of the open abdomen, epidermal skin harvesting, and advanced wound dressings. This supplement provides in-depth discussion of some of the topics covered at the 2014 ISWF.

A rabbit model of fat graft recipient site preconditioning using external negative pressure

Background

Fat is widely used in soft tissue augmentation. Nevertheless, it has an unpredictably high resorption rate. Clinically, external expansion with negative pressure is used to increase fat graft survival. In this study, fat graft recipient sites were preconditioned by external application of negative pressure in order to test for improvements in vascularity and fat graft survival.

Methods

Negative pressure was applied randomly to either the left or right dorsal ear of 20 New Zealand male white rabbits at a pressure of -125 mm Hg. The negative pressure was removed one week after the skin perfusion was measured. The skin flap at each ear was elevated, and 1 g of fat was grafted above the dorsal perichondrium. After one week, the fat weight, microvessel density, mature vessel density of the skin and fat, and amount of glycerol released were measured. Three months after the grafting, the same measurements were performed, with the exception of glycerol release.

Results

The fat survival rate of the experimental group (75.4%±3.9%) was higher than that of the control group (53.1%±4.3%) (P<0.001). Skin perfusion was higher in the experimental group. The glycerol release in the experimental group was significantly higher than in the control. The microvessel density of the skin and fat was significantly higher in the experimental group. Three months after the grafting, the skin and fat mature vessel density was significantly higher in the experimental groups.

Conclusions

Negative pressure prior to fat grafting increased the vascularity of the recipient site, and, accordingly, enhanced fat graft survival.

Optimization of photodynamic therapy using negative pressure

OBJECTIVE

The goal of this study is to demonstrate an alternative procedure to perform topical photodynamic therapy (PDT). Here, we propose the combined use of negative pressure and a 5-Aminolevulinic acid (5-ALA) cream occlusion to increase protoporphyrin IX (PPIX) formation.

BACKGROUND DATA

PDT using topical 5-ALA as a prodrug and precursor of PPIX has been used in the treatment and diagnosis of different types of cancer and skin diseases. The use of 5-ALA offers many advantages as a localized and non-systemic application, but it shows limitations in relation to skin penetration. Many authors have discussed the limitations of 5-ALA penetration through the skin. The skin penetration of 5-ALA can be optimized using mechanical devices associated with typical PDT procedure.

METHODS

For this study, 20% 5-ALA cream was applied to a 9 cm(2) area of skin, and an occlusive dressing was placed. The PPIX production was collected at the skin surface, using fluorescence spectroscopy and widefield fluorescence imaging, for 7 h, and after 24 h.

RESULTS

We observed that in the presence of negative pressure therapy, the PPIX production, distribution, and elimination are greater and faster than in the control group. The PPIX formation was ∼30% in deeper skin layers, quantified by fluorescence spectroscopy analysis, and ∼20% in surface skin layers, quantified by widefield fluorescence imaging analysis.

CONCLUSIONS

Negative pressure induction can also help PDT application in the case of inefficient PPIX production. These results can be useful for optimizing the PDT.

Negative-pressure wound therapy induces endothelial progenitor cell mobilization in diabetic patients with foot infection or skin defects

Non healing chronic wounds are difficult to treat in patients with diabetes and can result in severe medical problems for these patients and for society. Negative-pressure wound therapy (NPWT) has been adopted to treat intractable chronic wounds and has been reported to be effective. However, the mechanisms underlying the effects of this treatment have not been elucidated. To assess the vasculogenic effect of NPWT, we evaluated the systemic mobilization of endothelial progenitor cells (EPCs) during NPWT. Twenty-two of 29 consecutive patients who presented at the clinic of Seoul National Universty Hospital between December 2009 and November 2010 who underwent NPWT for diabetic foot infections or skin ulcers were included in this study. Peripheral blood samples were taken before NPWT (pre-NPWT) and 7–14 days after the initiation of NPWT (during-NPWT). Fluorescence-activated cell sorting (FACS) analysis showed that the number of cells in EPC-enriched fractions increased after NPWT, and the numbers of EPC colony forming units (CFUs) significantly increased during NPWT. We believe that NPWT is useful for treating patients with diabetic foot infections and skin ulcers, especially when these conditions are accompanied by peripheral arterial insufficiency. The systemic mobilization of EPCs during NPWT may be a mechanism for healing intractable wounds in diabetic patients with foot infections or skin defects via the formation of increased granulation tissue with numerous small blood vessels.

Vacuum-assisted closure therapy as an alternative treatment of subcutaneous emphysema

Vacuum-assisted closure therapy is an alternative method for a massive subcutaneous emphysema treatment. It is easily applicable and shows rapid effectiveness in massive subcutaneous emphysema, intractable with chest tube drainage.

High bacterial load in negative pressure wound therapy (NPWT) foams used in the treatment of chronic wounds

No earlier study has investigated the microbiology of negative pressure wound therapy (NPWT) foam using a standardized manner. The purpose of this study is to investigate the bacterial load and microbiological dynamics in NPWT foam removed from chronic wounds (>3 months). To determine the bacterial load, a standardized size of the removed NPWT foam was sonicated. The resulting sonication fluid was cultured, and the colony-forming units (CFU) of each species were enumerated. Sixty-eight foams from 17 patients (mean age 63 years, 71% males) were investigated. In 65 (97%) foams, ≥ 1 and in 37 (54%) ≥ 2 bacterial types were found. The bacterial load remained high during NPWT treatment, ranging from 10(4) to 10(6) CFU/ml. In three patients (27%), additional type of bacteria was found in subsequent foam cultures. The mean bacterial count ± standard deviation was higher in polyvinyl alcohol foam (6.1 ± 0.5 CFU/ml) than in polyurethane (5.5 ± 0.8 CFU/ml) (p = 0.02). The mean of log of sum of CFU/ml in foam from 125 mmHg (5.5 ± 0.8) was lower than in foam from 100 mmHg pressure (5.9 ± 0.5) (p = 0.01). Concluding, bacterial load remains high in NPWT foam, and routine changing does not reduce the load.

Evidence-based topical management of chronic wounds according to the T.I.M.E. principle

The number of patients suffering from chronic wound healing disorders in Germany alone is estimated to be 2.5-4 million. Therapy related expenses reach 5-8 billion Euros annually. This number is partially caused by costly dressing changes due to non-standardized approaches and the application of non-evidence-based topical wound therapies. The purpose of this paper is to elucidate a straightforward principle for the management of chronic wounds, and to review the available evidence for the particular therapy options. The T.I.M.E.-principle (Tissue management, Inflammation and infection control, Moisture balance, Epithelial [edge] advancement) was chosen as a systematic strategy for wound bed preparation. Literature was retrieved from the PubMed and Cochrane Library databases and subjected to selective analysis. Topical wound management should be carried out according to a standardized principle and should further be synchronized to the phases of wound healing. Despite the broad implementation of these products in clinical practice, often no benefit exists in the rate of healing, when evaluated in meta-analyses or systematic reviews. This insufficient evidence is additionally limited by varying study designs. In case of non-superiority, the results suggest to prefer relatively inexpensive wound dressings over expensive alternatives. Arbitrary endpoints to prove the effectiveness of wound dressings, contribute to the random use of such therapies. Defining rational endpoints for future studies as well as the deployment of structured therapy strategies will be essential for the economical and evidence-based management of chronic wounds.

Free flap transplantation combined with skin grafting and vacuum sealing drainage for repair of circumferential or sub-circumferential soft-tissue wounds of the lower leg

Background

This study is aimed at evaluating the operation techniques and clinical significance of free flap transplantation combined with skin grafting and vacuum sealing drainage (VSD) in repairing severe traumatic extensive circumferential or semi-circumferential soft-tissue defects of the lower leg.

Material/Methods

Thirty patients with severe lower leg injuries were treated by free flap transplantation combined with skin grafting and VSD from January 2008 to June 2011. The size of the wounds ranged from 23×8 cm to 44×28 cm and all affected more 70% of the low leg circumferential area. Wounds were complicated by exposure, necrosis, or infection of deep tissues. The wounds were first debrided and covered by VSD. When the condition of the wound had improved (5 to 7 days later), free flaps were harvested to reconstruct damaged tissue and skin grafts and VSD was used to cover granulation tissues around the transplanted flap.

Results

Granulation tissues developed and the area requiring flap cover decreased in all 30 patients after debridement and VSD. In 28 of 30 cases, the transplanted flaps grew well without complication. Peripheral necrosis was observed in only 2 cases, which required a second debridement and skin graft. Ten wound areas covered by grafts were left with scattered peripheral wounds, which healed with the help of 1 more skin graft or dressing change. Morphological appearance and functional recovery were satisfactory in all 30 cases.

Conclusions

Initial debridement and the temporary VSD cover followed after several days by free flap transplantation combined with skin grafting and VSD protection is a reliable treatment regimen for traumatic large circumferential or sub-circumferential soft tissue wounds of the lower leg with deep tissue exposure.

Current achievements with topical negative pressure to improve wound healing in dehiscent ischemic stumps of diabetic patients: a case series

Negative pressure wound therapy has been increasingly used either as a primary or as an adjunctive therapeutic measure to treat a variety of recalcitrant wounds during the past years. It is thought to act by creating a local environment that promotes cell proliferation, angiogenesis, and granulation tissue formation, leading to accelerated wound healing to the point of spontaneous closure or reducing the wound size to facilitate significantly further surgical reconstruction. This case series presents our preliminary experience with the use of a Topical Negative Pressure system in the treatment of challenging ischemic wounds of diabetic patients. It aims to underscore its beneficial effects and explore its potential role in the management of ischemic amputated stumps to avoid ipsilateral re-amputation at a higher level.

[Vacuum assisted closure therapy in dehiscence of abdominal wound after cesarean section treated in a hospital-at-home]

The Hospital at Home is a range of hospital care provided to patients in the comfort of their own homes, so patient and family can actively participate in the process. Cesarean section is a surgical procedure that requires a short hospital stay. However if complications arise during the process, such as a dehiscence of surgical wound, the hospital stay is prolonged, delaying mother-child bonding, which is very important for the growth of the child. Nursing care in wound healing by secondary intention is a priority for the patient's recovery. VAC therapy (vacuum assisted closure) promotes a rapid recovery, although it requires dressings and active medical surveillance, as well as training by the nursing staff for carrying it out at home. We describe the outcome and the process of the healing of a surgical wound after cesarean section, not only because of a complex wound, but the previously mentioned factors that make us consider the Hospital at Home as the best alternative care.

Pain and trauma in negative pressure wound therapy: a review

Negative pressure wound therapy (NPWT) is considered an effective wound treatment, but there are a number of issues that need to be addressed for improvements to be made. This review aimed to explore the literature relating to the pain and skin trauma that may be experienced during NPWT. A literature search was carried out using the following databases: Academic Search Complete, CINAHL, PsychINFO, MEDLINE and PsyARTICLES. A total of 30 articles were reviewed. Studies reported varying levels of pain in patients undergoing NPWT, with certain treatment factors affecting the level of pain, such as the NPWT system and the dressing/filler used. Similarly, although there is much less research exploring NPWT-related trauma, findings suggest that dressing and filler type may impact on whether trauma occurs. However, further research needs to consider the different stages of NPWT and how pain and trauma can be minimised during the whole procedure. As both pain and skin trauma impact on the patient's well-being and on wound healing, it is essential that research further explores the factors that may affect the experience of pain and trauma, so as to inform developments in wound care.