Healed porcine incisions previously treated with a surgical incision management system: mechanical, histomorphometric, and gene expression properties

The use of incisional negative pressure wound therapy on high-risk breast cancer mastectomy patients

BACKGROUND

The main complications seen in patients who have undergone modified radical mastectomy (MRM) are seroma, surgical site infection, hematoma, wound dehiscence, flap necrosis, and nerve damage. While these complications lead to some problems the most feared effect in the early period is that they cause a delay in adjuvant treatment. Incisional Negative Pressure Wound Therapy (iNPWT) decreases wound dehiscence by reducing oedema and tension, especially in the incision line. This study aim to compare recovery times and wound site complications between patients treated with conventional wound dressings and patients treated with iNPWT after MRM.

METHODS

A retrospective screening was made of the data of 50 patients who underwent MRM because of breast cancer in the General Surgery Clinic of XXX Hospital between 2018 and 2022, and were at high-risk of wound site complications. Two groups were formed as 30 patients applied with iNPWT and 20 patients applied with conventional dressings.

RESULTS

The mean age of the 50 female patients was 53.58 years (range, 30-80 years). The most frequently seen complications were seroma (20 patients) and partial flap ischaemia (14 patients). The mean number of iNPWT applications was 1.30 (range, 1-2), and the mean number of days of application was 4.47 (range, 2-9). Postoperative seroma was observed in 8 patients in the iNPWT group and in 12 patients in the conventional dressings group (p = 0.018). Flap ischaemia and the probability of dehiscence was determined at a statistically significantly higher rate in the patients in the conventional dressings groups (p = 0.005, p = 0.021).

CONCLUSION

The results of this study demonstrated that the use of iNPWT significantly reduced the amount of postoperative drainage, thereby contributing to early drain removal. Furthermore, iNPWT significantly reduced postoperative seroma, flap ischaemia, and flap dehiscence compared to conventional dressings.

Multicenter parallel randomized trial evaluating incisional negative pressure wound therapy for the prevention of surgical site infection after lower extremity bypass

OBJECTIVE

Incisional negative pressure wound therapy (iNPWT) applied over all incisions after lower extremity bypass in the prevention of surgical site infections (SSIs) is unclear. The primary and secondary aims of this study were to investigate if prophylactic iNPWT after the elective lower extremity bypass prevents SSI and other surgical wound complications.

METHODS

This was a multicenter, parallel, randomized controlled trial. Patients undergoing elective lower extremity bypass in 3 hospitals were randomized to either iNPWT or standard dressings. SSIs or other wound complications were assessed within the first 90 days by wound care professionals blinded to the randomized result. The validated Additional treatment, Serous discharge, Erythema, Purulent exudate, Separation of deep tissues, Isolation of bacteria, and Stay (ASEPSIS) score was used to objectively assess the wounds. ASEPSIS score ≥21 is defined as an SSI. Unilateral and bilateral groups were analyzed with the Fisher exact test and the McNemar test, respectively.

RESULTS

In the unilateral group (n = 100), the incidence of SSI in the iNPWT group was 34.9% (15/43), compared with 40.3% (23/57) in the control group, according to the ASEPSIS score (P = .678). In the bilateral group (n = 7), the SSI rate was 14.3% (1/7) in the iNPWT group compared with 14.3% (1/7) in the control group (P = 1.00). In the unilateral group, there was a higher wound dehiscence rate in the control group (43.9%) compared with the iNPWT group (23.3%) (P = .0366). No serious iNPWT-related adverse events were recorded.

CONCLUSIONS

There was no reduction of SSI rates in leg incisions with iNPWT compared with standard dressings in patients undergoing elective lower extremity bypass, whereas iNPWT reduced the incidence of wound dehiscence.

Modulation of Lymphangiogenesis in Incisional Murine Diabetic Wound Healing Using Negative Pressure Wound Therapy

Objective: Despite the significant function of lymphatics in wound healing, and frequent clinical use of Negative Pressure Wound Therapy (NPWT), the effect of mechanical force application on lymphangiogenesis remains to be elucidated. We utilize a murine incisional wound healing model to assess the mechanisms of lymphangiogenesis following NPWT. Approach: Dorsal incisional skin wounds were created on diabetic mice (genetically obese leptin receptor-deficient mice [db/db]; n = 30) and covered with an occlusive dressing (Control, n = 15) or NPWT (-125 mmHg, continuous, 24 h for 7 days; NPWT, n = 15). The wounds were macroscopically assessed for 28 days. Tissue was harvested on day 10 for analysis. Qualitative functional analysis of lymphatic drainage was performed on day 28 using Evans Blue staining (n = 2). Results: NPWT increased lymphatic vessel density (40 ± 20 vs. 12 ± 6 podoplanin [PDPN]⁺ and 25 ± 9 vs. 14 ± 8 lymphatic vessel endothelial receptor 1 [LYVE-1]⁺) and vessel diameter (28 ± 9 vs. 12 ± 2 μm). Western blotting verified the upregulation of LYVE-1 with NPWT. Leukocyte presence was higher with NPWT (22% ± 3.7% vs. 9.1% ± 4.1% lymphocyte common antigen [CD45]⁺) and the leukocytes were predominately B cells clustered within vessels (8.8% ± 2.5% vs. 18% ± 3.6% B-lymphocyte antigen CD20 [CD20]⁺). Macrophage presence was lower in the NPWT group. Lymphatic drainage was increased in the NPWT group, which exhibited greater Evans Blue positivity. Innovation: The lymphangiogenic effects take place independent of macrophage infiltration, appearing to correlate with B cell presence. Conclusion: NPWT promotes lymphangiogenesis in incisional wounds, significantly increasing the lymph vessel density and diameter. This study highlights the potential of NPWT to stimulate lymphatic drainage and wound healing of surgical incisions.

The Effect of Negative Pressure on Wound Healing and Regeneration in Closed Incisions under High Tension: Evidence from Animal Studies and Clinical Experience

Closed-incision negative-pressure wound therapy (iNPWT) is known to enhance wound healing and tissue regeneration. The main aim of the present study is to investigate its effectiveness on enhancing wound healing under tension. An animal study was designed using a swine model by removing a skin flap to create a wound that could be closed primarily under tension, and iNPWT was applied. The enhancement of angiogenesis, lymphangiogenesis, collagen deposition, and tissue proliferation with reduced inflammation by iNPWT was confirmed by histology. The effect of iNPWT was further verified in patients receiving a profunda artery perforator (PAP) free flap for breast reconstruction. iNPWT was applied on the transversely designed donor site in continuous mode for 7 days, in which the wound was always closed under tension. A significant improvement in off-bed time was noted with the application of iNPWT (4.6 ± 1.1st and 5.5 ± 0.8th postoperative days in the iNPWT and control groups, respectively, p = 0.028). The control group (without iNPWT treatment) presented more cases of poor wound healing in the acute (23.1% vs. 0%) and wound breakdown in the late (23.1% vs. 8.3%) stages. The treatment of closed incisions under tension with iNPWT clinically enhances wound healing and tissue regeneration and with histological evidence.

Negative Pressure Wound Therapy in Spinal Surgery

Negative pressure wound therapy (NPWT) has demonstrated promise in the management of surgical site infections as well as assisting in surgical wound healing. In this manuscript, we describe the mechanisms and applications of NPWT for surgical wounds and existing evidence for NPWT in cardiac, plastic, and general surgery, followed by a discussion of the emerging evidence base for NPWT in spinal surgery. We also discuss the different applications of NPWT for open wounds and closed incisions, and the promise of newer closed-incision NPWT (ciNPWT) devices. There is nominal but promising prospective evidence on NPWT's efficacy in select at-risk populations for post-operative wound complications after spinal surgery. As there is currently a paucity of robust clinical evidence on its efficacy, rigorous randomized prospective clinical trials are needed.

Continuous NPWT Regulates Fibrosis in Murine Diabetic Wound Healing

Scarring is associated with significant morbidity. The mechanical signaling factor yes-associated protein (YAP) has been linked to Engrailed-1 (En1)-lineage positive fibroblasts (EPFs), a pro-scarring fibroblast lineage, establishing a connection between mechanotransduction and fibrosis. In this study, we investigate the impact of micromechanical forces exerted through negative pressure wound therapy (NPWT) on the pathophysiology of fibrosis. Full-thickness excisional dorsal skin wounds were created on diabetic (db/db) mice which were treated with occlusive covering (control) or NPWT (continuous, −125 mmHg, 7 days; NPWT). Analysis was performed on tissue harvested 10 days after wounding. NPWT was associated with increased YAP (p = 0.04) but decreased En1 (p = 0.0001) and CD26 (p < 0.0001). The pro-fibrotic factors Vimentin (p = 0.04), α-SMA (p = 0.04) and HSP47 (p = 0.0008) were decreased with NPWT. Fibronectin was higher (p = 0.01) and collagen deposition lower in the NPWT group (p = 0.02). NPWT increased cellular proliferation (p = 0.002) and decreased apoptosis (p = 0.03). Western blotting demonstrated increased YAP (p = 0.02) and RhoA (p = 0.03) and decreased Caspase-3 (p = 0.03) with NPWT. NPWT uncouples YAP from EPF activation, through downregulation of Caspace-3, a pro-apoptotic factor linked to keloid formation. Mechanotransduction decreases multiple pro-fibrotic factors. Through this multifactorial process, NPWT significantly decreases fibrosis and offers promising potential as a mode to improve scar appearance.

The Utility of Closed Incision Negative Pressure Wound Therapy following Spinal Fusion: A Systematic Review and Meta-Analysis

OBJECTIVES

To determine if closed incision negative pressure wound therapy (ciNPWT) decreases surgical site infection (SSI) or wound dehiscence following spinal fusion.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, a systematic review and meta-analysis was conducted to identify studies utilizing ciNPWT following spinal fusion. Funnel plots and quality scores of the articles were performed to determine if the articles were at risk of bias. Forest plots were conducted to identify the treatment effect of ciNPWT following spinal fusion.

RESULTS

A total of 8 studies comprising 1,061 patients who received ciNPWT or a standard postoperative dressing following spinal fusion were included. The rate of SSI [ciNPWT: 4.49% (95% CI: 2.48, 8.00) vs. control: 11.32% (95% CI: 7.51, 16.70), p=0.0103] was significantly lower for patients treated with ciNPWT. A fixed-effects model showed no significant difference between patients who received ciNWPT or a standard postoperative dressing with respect to requiring reoperations for wound debridement (OR: 1.25, 95% CI: 0.64, 2.41). Additionally, wound dehiscence was not significantly different between the two groups although it was non-significantly lower in ciNWPT-treated patients [ciNPWT: 4.59% (95% CI: 2.49, 8.31) vs control: 7.48% (95% CI: 4.38, 12.47), p=0.23].

CONCLUSION

Closed incision NPWT may reduce the rates of SSI following spinal fusion. The use of ciNWPT may also significantly reduce the burden associated with postoperative wound complications, but the meta-analysis was insufficiently powered to make this association. Additional, studies may identify a subset of patients who benefit from ciNPWT for other wound-related complications.

"Closed Incision Negative Pressure Therapy (ciNPT) reduces abdominal donor site surgical wound dehiscence in Deep Internal Epigastric Perforator (DIEP) flap breast reconstructions: DEhiscence PREvention Study II (DEPRES II) - a Randomized Clinical Trial"

BACKGROUND

In breast reconstruction surgeries, surgical wound dehiscence is a serious complication which generates a significant burden on patients and healthcare systems. There are indications that postoperative treatment with closed incision negative pressure therapy (ciNPT) has been associated with reduced wound dehiscence rates. This randomized clinical trial examines the effect of ciNPT application on abdominal donor site surgical wound dehiscence in low- and high-risk patients undergoing a breast reconstruction with a deep internal epigastric perforator (DIEP) flap.

METHODS

Eighty eligible women, stratified as low- or high-risk patients, were included and were randomized for treatment with either ciNPT or adhesive strips (AS) by drawing sealed, opaque envelopes. All surgeons were kept blind for allocation. Primary outcomes were surgical wound dehiscence and surgical site infection at the abdominal donor site upon follow-up after 12 weeks. Secondary outcomes were seroma and hematoma formation. Five patients were excluded from the study due to non-sufficient exposure to the study treatment (n=4) or major protocol deviation (n=1).

RESULTS

A total of 75 women, low-risk (n=38) and high-risk (n=37), received either ciNPT (n=36) or AS (n=39). Patients' demographics did not differ significantly. Donor-site surgical wound dehiscence occurred in 23 patients; the Absolute Risk Reduction was statistically significant (21.6%, 95% Confidence Interval [1.5-41.7]). No statistically significant differences were found in surgical site infection or secondary outcomes.

CONCLUSIONS

In this randomized clinical trial, postoperative treatment with ciNPT decreased the incidence of surgical wound dehiscence at the abdominal donor site in low- and high-risk DIEP flap breast reconstruction patients.

The Impact of Incisional Negative Pressure Wound on Scar Quality and Patient Reported Outcomes: a Within-Patient Controlled, Randomized Trial

Literature provides a moderate level of evidence for the beneficial effects of incisional negative pressure wound therapy (iNPWT) on scar quality. The purpose of this study was to establish if iNPWT results in improved scar outcomes in comparison to the standard of care. Therefore, a within‐patient randomised controlled, open‐label trial was conducted in transgender men undergoing gender‐affirming mastectomies. A unilateral side was randomised to receive iNPWT (PICO™, Smith&Nephew) without suction drains and contrastingly the standard dressing (Steri‐Strips™) with suction drain. Scar quality and questionnaires were bilaterally measured by means of objective assessments and patient‐reported outcome measures (PROM) at 1, 3 and 12 months. Objective scar outcomes were scar pliability (Cutometer®), colouration (DSM‐II) and scar width (3‐D imaging). PROM outcomes were related to scars (POSAS and SCAR‐Q) and body satisfaction (BODY‐Q). From 85 included patients, 80 were included for analyses. No significant difference between treatments was seen in the quantitative outcomes of scar pliability, colour, and width. For qualitative scar outcomes, several significant findings for iNPWT were found for several subscales of the POSAS, SCAR‐Q, and BODY‐Q. These effects could not be substantiated with linear mixed‐model regression, signifying no statically more favourable outcome for either treatment option. In conclusion, this study demonstrated that some PROM outcomes were more favourable for the iNPWT compared to standard treatment. In contrast, the quantitative outcomes showed no beneficial effects of iNPWT on scar outcomes. This suggests that iNPWT is of little benefit as a scar‐improving therapy.

Simple and Efficient Pressure Ulcer Reconstruction via Primary Closure Combined with Closed-Incision Negative Pressure Wound Therapy (CiNPWT)—Experience of a Single Surgeon

Background: In this study, we aimed to analyze the clinical efficacy of closed-incision negative pressure wound therapy (CiNPWT) when combined with primary closure (PC) in a patient with pressure ulcers, based on one single surgeon’s experience at our medical center. Methods: We retrospectively reviewed the data of patients with stage III or IV pressure ulcers who underwent reconstruction surgery. Patient characteristics, including age, sex, cause and location of defect, comorbidities, lesion size, wound reconstruction methods, operation time, debridement times, application of CiNPWT to reconstructed wounds, duration of hospital stay, and wound complications were analyzed. Results: Operation time (38.16 ± 14.02 vs. 84.73 ± 48.55 min) and duration of hospitalization (36.78 ± 26.92 vs. 56.70 ± 58.43 days) were shorter in the PC + CiNPWT group than in the traditional group. The frequency of debridement (2.13 ± 0.98 vs. 2.76 ± 2.20 times) was also lower in the PC + CiNPWT group than in the traditional group. The average reconstructed wound size did not significantly differ between the groups (63.47 ± 42.70 vs. 62.85 ± 49.94 cm²), and there were no significant differences in wound healing (81.25% vs. 75.38%), minor complications (18.75% vs. 21.54%), major complications (0% vs. 3.85%), or mortality (6.25% vs. 10.00%) between the groups. Conclusions: Our findings indicate that PC combined with CiNPWT represents an alternative reconstruction option for patients with pressure ulcers, especially in those for whom prolonged anesthesia is unsuitable.

Effect of closed incision negative pressure wound therapy on incidence rate of surgical site infection after stoma reversal: a pilot study

INTRODUCTION

The stoma reversal (SR) procedure is associated with a relatively high risk of perioperative complications with surgical site infection (SSI) as the most common. Recently closed incision negative pressure wound therapy (ciNPWT) was applied widely to prevent SSI.

AIM

To investigate the efficiency of ciNPWT in terms of the incidence rate of SSI after SR surgery.

MATERIAL AND METHODS

As an exploratory observational cohort study patients were treated either with ciNPWT (n = 15) or standard sterile dressing (SSD) (n = 15). CiNPWT was applied every 3 days whereas SSD was changed every day. Clinical evaluation for SSI signs, C-reactive protein level and pain assessment using the visual analogue scale (VAS) were analyzed.

RESULTS

The incidence rate of SSI was in 13% (2/15) in the ciNPWT group and 26% (4/15) in the SSD group (p = 0.651, OR = 0.44, 95% CI: 0.03-3.73). All patients in the SSD group who developed SSI presented both local and generalized signs of infection. Pain-VAS levels assessed on the 1st (MdnciNPWT = 4, MdnSSD = 5, p = 0.027, W = 51.5) and 3rd postoperative day (MdnciNPWT = 2, MdnSSD = 4, p = 0.014, W = 45.5) were significantly lower in the ciNPWT group than in the SSD group.

CONCLUSIONS

CiNPWT seems not to have a benefit to reduce SSI after the SR procedure. Further investigation is needed to establish firmly the benefit of using ciNPWT in this group of patients.

The application of close incisional negative pressure wound therapy in revision arthroplasty among asian patients: a comparative study

INTRODUCTION

Peri-prosthetic joint infection (PJI) was one of the main causes of revision of arthroplasty. In order to reduce wound complications and surgical site infections, close incisional negative pressure wound therapy (ciNPWT) has been introduced into arthroplasty. This study was designed to review the clinical benefits of the application of ciNPWT in revision arthroplasty.

METHODS

This was a single-centre retrospective comparative study approved by the Institutional Review Board. Patients, who underwent revision total knee arthroplasty or revision total hip arthroplasty at the author's institution from January 2016 to October 2019, were included in this study. The ciNPWT cohort included all eligible patients, who underwent operations from January 2018 to October 2019, with the use of ciNPWT(n = 36). The control cohort included all eligible patients, who underwent operations from January 2016 to December 2017 with the use of conventional dressing(n = 48). The incidences of wound complications were compared to both cohorts.

RESULTS

There was a statistically significant difference in the rate of superficial surgical site infection (SSI) between control cohort and ciNPWT cohort (12.5% in control vs 0% in ciNPWT, p = 0.035). However, there was no statistically significance of the overall wound complication rate for both cohorts. (14.6% in control vs 8.3% in ciNPWT, p = 0.504).

CONCLUSIONS

The application of ciNPWT could result in a lower rate of superficial surgical site infection when compared with conventional dressing among the patients undergoing revision total knee and total hip arthroplasties.

TRIAL REGISTRATION

UW19-706.

Large abdominal hernia repair with closed incision negative pressure therapy: a case series

OBJECTIVE

A major challenge of large abdominal incisional hernia repair is the high rates of wound complications. Closed incision negative pressure therapy (CINPT) can offer many treatment advantages in the management of these wounds and has been shown to reduce complications for other postoperative incisions. This study assesses the wound outcomes for hernia repair patients receiving CINPT.

METHOD

A six-year retrospective case series of patients who had undergone large abdominal incisional hernia repair wounds treated with CINPT was conducted. Outcomes for patients treated with CINPT were compared with patients who had not received CINPT acting as a control.

RESULTS

A total of 23 patients were treated with CINPT after hernia repair and compared with 12 patients in the control group. A statistically significant decreased rate of return to theatre (odds ratio: 0.12) was found in this study. Non-significant reductions in wound infection, seroma and wound dehiscence were also seen. No adverse events with CINPT therapy were reported.

CONCLUSIONS

CINPT, when used after large abdominal incisional hernia repair, may help in the prevention of wound complications.

Vacuum-Assisted Incisional Closure Therapy After Groin Reconstruction With Muscle Flap

Background

Groin reconstruction with muscle flap coverage is associated with high wound complication rates. Incisional vacuum-assisted closure (iVAC) therapy may lower wound complications. We evaluated the impact of iVAC on postoperative outcomes in patients following groin reconstruction with muscle flap coverage.

Methods

We conducted a retrospective review of patients who underwent groin reconstruction with muscle flap coverage in 2012-2018. Patients were divided into those who received iVAC therapy and those who received standard sterile dressings (SSD).

Results

Of the 57 patients included, most received iVAC therapy (71%, n = 41) and the rest received SSD (28%, n = 16). The iVAC group had higher rates of diabetes, hypertension, coronary artery disease, and peripheral artery disease (p < 0.05). However, iVAC patients had comparable length of hospital stay (12 vs 8.5 days p = 0.0735), reoperations (34% vs 31%, p = 0.8415), and readmissions (32% vs 37%, p = 0.6801) with SSD patients. iVAC placement was less likely in prophylactic flaps (odds ratio 0.08, p = 0.0049).

Conclusion

Patients with a prophylactic flap were less likely to receive vacuum therapy, which may highlight a selection bias where surgeons pre-emptively use iVAC therapy in surgical candidates identified as high risk. The pre-emptive use of iVAC may minimize adverse postoperative outcomes in high-risk patients.

Closed-incision negative-pressure wound management in surgery—literature review and recommendations

Background

Wound healing deficits and subsequent surgical site infections are potential complications after surgical procedures, resulting in increased morbidity and treatment costs. Closed-incision negative-pressure wound therapy (ciNPWT) systems seem to reduce postoperative wound complications by sealing the wound and reducing tensile forces.

Materials and methods

We conducted a collaborative English literature review in the PubMed database including publications from 2009 to 2020 on ciNPWT use in five surgical subspecialities (orthopaedics and trauma, general surgery, plastic surgery, cardiac surgery and vascular surgery). With literature reviews, case reports and expert opinions excluded, the remaining 59 studies were critically summarized and evaluated with regard to their level of evidence.

Results

Of nine studies analysed in orthopaedics and trauma, positive results of ciNPWT were reported in 55.6%. In 11 of 13 (84.6%), 13 of 15 (86.7%) and 10 of 10 (100%) of studies analysed in plastic, vascular and general surgery, respectively, a positive effect of ciNPWT was observed. On the contrary, only 4 of 12 studies from cardiac surgery discovered positive effects of ciNPWT (33.3%).

Conclusion

ciNPWT is a promising treatment modality to improve postoperative wound healing, notably when facing increased tensile forces. To optimise ciNPWT benefits, indications for its use should be based on patient- and procedure-related risk factors.

A systematic review evaluating the influence of incisional Negative Pressure Wound Therapy on scarring

Pathological scars can result in functional impairment, disfigurement, a psychological burden, itch, and even chronic pain. We conducted a systematic review to investigate the influence of incisional Negative Pressure Wound Therapy (iNPWT) on scarring. PubMed, EMBASE and CINAHL were searched for preclinical and clinical comparative studies that investigated the influence of iNPWT on scarring‐related outcomes. Individual studies were assessed using the OHAT Risk of Bias Rating Tool for Human and Animal studies. The body of evidence was rated using OHAT methodology. Six preclinical studies and nine clinical studies (377 patients) were identified. Preclinical studies suggested that iNPWT reduced lateral tension on incisions, increased wound strength, and reduced scar width upon histological assessment. Two clinical studies reported improved patient‐reported scar satisfaction as measured with the PSAS (1 year after surgery), POSAS, and a VAS (both 42, 90, and 180 days after surgery). Five clinical studies reported improved observer‐reported scar satisfaction as measured with the VSS, SBSES, OSAS, MSS, VAS, and POSAS (7, 15, 30, 42, 90, 180, and 365 days after surgery). Three clinical studies did not detect significant differences at any point in time (POSAS, VAS, and NRS). Because of imprecision concerns, a moderate level of evidence was identified using OHAT methodology. Preclinical as well as clinical evidence indicates a beneficial influence of iNPWT on scarring. Moderate level evidence indicates that iNPWT decreases scar width and improves patient and observer‐reported scar satisfaction.

Assessment of Silver Levels in a Closed-Incision Negative Pressure Therapy Dressing: In Vitro and In Vivo Study

Objective: In recent years, reticulated open-cell foam-based closed-incision negative pressure therapy (ROCF-ciNPT) has shown effectiveness in management of various postoperative incisions. These dressings consist of a skin interface layer that absorbs fluid from the skin surface and reduces the potential for microbial colonization within the dressing by means of ionic silver. This study examines the ability of silver to reduce the bioburden within the dressing as well as the localized effect due to potential silver mobility.

Approach: Ability of silver to reduce bioburden within the ROCF-ciNPT dressing was assessed using Staphylococcus aureus, Pseudomonas aeruginosa, and Candida spp. Furthermore, silver mobility was assessed using an in vitro skin model to study the zone of inhibition along with released silver quantification. Using a porcine model, diffusion of silver into blood and tissue was studied using emission spectrometry and histology.

Results: Microbial growth in the ROCF-ciNPT dressing was significantly reduced (∼2.7–4.9 log reduction) compared to a silver-free negative control. No zone of inhibition was observed for microbial colonies for up to 7 days with minimal localized silver release (<5.5 ppm release). In vivo studies demonstrated no measurable concentration (<0.2 μg/g) of silver in the blood, urine, feces, kidney, and liver tissue biopsy.

Innovation: This study provides an important insight into silver concentration and mobility within the ROCF-ciNPT dressing, given emerging concerns associated with potential silver cytotoxicity.

Conclusion: These results indicate the concentration of silver (0.019% silver by weight) in the ROCF-ciNPT dressings has been adequate to reduce bioburden within the skin interface layer, while severely limiting the amount of silver leaching out.

Clinical Experiences with Closed Incisional Negative Pressure Wound Treatment on Various Anatomic Locations

Background

Closed incisional negative pressure wound treatment (ciNPWT) is one of the promising methods for the prevention of complications in surgical incisions. The mechanisms of ciNPWT have previously been elucidated and in this series, we demonstrate various, as of yet, underreported uses for the technology. Our aim is to share our experience with ciNPWT on various anatomic sites with novel indications. 

Materials and methods

ciNPWT was used in 24 patients. The mean age was 49.6. All the incisions were sutured, clean, and non-infected. Patients’ sex, age, comorbidities, anatomic location of the wound, and the indications for ciNPWT were recorded.

Results

The mean number of applications was three per patient. One suture dehiscence after one session of ciNPWT was encountered in a flap donor site of an infant operated for meningomyelocele. Late-term seroma and hematoma formation were encountered in two patients. No surgical site infection, wound dehiscence, and ciNPWT related complications were seen in other patients. The majority of the applications were on the trunk, lower extremity, pelvis, upper extremity, and scalp respectively. Indications for ciNPWT utilization were preventing dehiscence, seroma, and hematoma formation in the majority of the patients.

Conclusion

ciNPWT is reliable and effective in the prevention of post-operative wound dehiscence and surgical site infections. It can be used safely in various locations and different indications for preventingcomplications such as preventing dehiscence in revision surgeries, cerebrospinal fluid (CSF) fistula formation in the scalp, and wound breakdown in chronic corticosteroid use,

Are high-risk patient and revision arthroplasty effective indications for closed-incisional negative-pressure wound therapy after total hip or knee arthroplasty? A systematic review and meta-analysis

To determine the effective indications of closed-incisional negative-pressure wound therapy (ciNPWT) following total hip or knee arthroplasty, this systematic review and meta-analysis was conducted. The systematic search was performed on MEDLINE, Embase, and Cochrane Library, and 11 studies were included. The studies comparing between ciNPWT and conventional dressings were categorised into following subgroups based on patient risk and revision procedures: routine vs high-risk patient; primary vs revision arthroplasty. Pooled estimates were calculated for wound complication and surgical site infection (SSI) rates in the subgroup analyses using Review Manager. In high-risk patients, the overall rates of wound complication (odds ratio [OR] = 0.38; 95% confidence interval [CI] 0.15-0.93; P = .030) and SSI (OR = 0.24; 95% CI = 0.09-0.64; P = .005) were significantly lower in the ciNPWT; however, there were no differences in routine patients. In cases involving revision arthroplasties, the overall rates of wound complication (OR = 0.33; 95% CI = 0.18-0.62; P < .001) and SSI (OR = 0.26; 95% CI = 0.11-0.66; P = .004) were significantly lower in the ciNPWT; however, there were no differences in cases involving primary arthroplasties. In summary, ciNPWT showed a positive effect in decreasing the rates of wound complication and SSI in high-risk patients and in revision arthroplasties.

Closed Incision Negative Pressure Wound Therapy After Resection of Large, Radiated, Soft Tissue Sarcomas

Negative pressure wound therapy (NPWT) has revolutionized wound care. Negative pressure therapy (NPT) is now being applied to closed incisions. Closed-incision NPT (ciNPT) management systems apply negative pressure to the incision and structurally stabilize the surrounding tissues. They are thought to be helpful in high-risk surgical closure. Patients with large sarcomas that have been previously radiated are considered to be among the highest risk for postoperative wound complications. We share our experience with ciNPT in two patients after resection of large, previously irradiated invasive sarcomas. In both cases, healing was uncomplicated. ciNPT shows promise of effective and favorable wound healing in early case reports. Additional prospective randomized clinical trials or registry studies will be necessary to provide higher levels of evidence for this technique.

Deep Learning-Based Risk Model for Best Management of Closed Groin Incisions After Vascular Surgery

BACKGROUND

Reduced surgical site infection (SSI) rates have been reported with use of closed incision negative pressure therapy (ciNPT) in high-risk patients.

METHODS

A deep learning-based, risk-based prediction model was developed from a large national database of 72,435 patients who received infrainguinal vascular surgeries involving upper thigh/groin incisions. Patient demographics, histories, laboratory values, and other variables were inputs to the multilayered, adaptive model. The model was then retrospectively applied to a prospectively tracked single hospital data set of 370 similar patients undergoing vascular surgery, with ciNPT or control dressings applied over the closed incision at the surgeon's discretion. Objective predictive risk scores were generated for each patient and used to categorize patients as "high" or "low" predicted risk for SSI.

RESULTS

Actual institutional cohort SSI rates were 10/148 (6.8%) and 28/134 (20.9%) for high-risk ciNPT versus control, respectively (P < 0.001), and 3/31 (9.7%) and 5/57 (8.8%) for low-risk ciNPT versus control, respectively (P = 0.99). Application of the model to the institutional cohort suggested that 205/370 (55.4%) patients were matched with their appropriate intervention over closed surgical incision (high risk with ciNPT or low risk with control), and 165/370 (44.6%) were inappropriately matched. With the model applied to the cohort, the predicted SSI rate with perfect utilization would be 27/370 (7.3%), versus 12.4% actual rate, with estimated cost savings of $231-$458 per patient.

CONCLUSIONS

Compared with a subjective practice strategy, an objective risk-based strategy using prediction software may be associated with superior results in optimizing SSI rates and costs after vascular surgery.

Evaluation of closed incision negative pressure therapy systems on the closure of incisional space model

OBJECTIVE

The objective of this study was to compare the ability of foam dressing-based and non-foam-based closed incision negative pressure therapy (ciNPT) systems to close isolated incisional deficits in a tissue model.

METHODS

Similarly sized foam-based and non-foam-based absorbent ciNPT dressings were applied to ~36cm long, ~3mm and ~6mm wide simulated incisions in gel sheets covered with drape (n=6 dressings/group/experimental condition spread over three respective therapy units). Changes in incision widths were measured directly or with overlying solid gel sheeting (to mimic tissue resistance), at five equally spaced locations before, immediately upon and one hour after initiating negative pressure using associated therapy units.

RESULTS

Foam-based ciNPT closed simulated incisions more often than non-foam-based ciNPT in all tested conditions (p<0.05). While foam-based ciNPT almost completely closed the ~3mm wide incisional spaces, unlike non-foam-based ciNPT, the biggest differences between the two groups were observed with the ~6mm incisional width, which allowed maximal inward-stretching of the appositional faces without complete closure. The additional gel layer blunted closure in both groups, but much more with non-foam-based ciNPT. There was minimal impact of negative pressure duration on these results.

CONCLUSION

Foam-based ciNPT closed incisional widths in simulated tissue significantly more compared with non-foam-based ciNPT. Different ciNPT systems should not be considered necessarily equivalent in performance.

Comparison of the Efficacy Between Closed Incisional Negative-Pressure Wound Therapy and Conventional Wound Management After Total Hip and Knee Arthroplasties: A Systematic Review and Meta-Analysis

BACKGROUND

Wound-related problems after total hip arthroplasty (THA) and total knee arthroplasty (TKA) can cause periprosthetic joint infections. We sought to evaluate the effect of closed incisional negative-pressure wound therapy (ciNPWT) on wound complications, skin blisters, surgical site infections (SSIs), reoperations, and length of hospitalization (LOH).

METHODS

Studies comparing ciNPWT with conventional dressings following THA and TKA were systematically searched on MEDLINE, Embase, and the Cochrane Library. Two reviewers performed the study selection, risk of bias assessment, and data extraction. Funnel plots were employed to evaluate publication bias and forest plots to analyze pooled data.

RESULTS

Twelve studies were included herein. The odds ratios (ORs) for wound complications and SSIs indicated a lack of publication bias. ciNPWT showed significantly lower risks of wound complication (OR, 0.44; 95% confidence interval [CI], 0.22-0.9; P = .027) and SSI (OR, 0.39; 95% CI, 0.23-0.68; P < .001) than did conventional dressings. ciNPWT also yielded a significantly lower reoperation rate (OR, 0.38; 95% CI, 0.21-0.69; P = .001) and shorter LOH (mean difference, 0.41 days; 95% CI, -0.51 to -0.32; P < .001). However, the rate of skin blisters was higher in ciNPWT (OR, 4.44; 95% CI, 2.24-8.79; P < .001).

CONCLUSION

Although skin blisters were more likely to develop in ciNPWT, the risks of wound complication, SSI, reoperation, and longer LOH decreased in ciNPWT compared with those in conventional dressings. This finding could alleviate the potential concerns regarding wound-related problems after THA and TKA.

Using negative pressure wound therapy to prevent surgical site infection

It is estimated that, at the very least, 5% of patients who undergo surgery develop a surgical site infection (SSI). There has been much interest in the use of negative pressure wound therapy (NPWT) as a prophylactic treatment to reduce the risk of SSI. Evidence suggests it can accelerate healing times, reduce both the length of hospital stay and the frequency of dressing changes, and improve patients' quality of life. The efficacy of traditional and portable NPWT systems is similar. However, the latter has an advantage in that it increases patient mobility and does not hinder individuals from carrying out activities of daily living. There are also economic data suggesting that portable NPWT devices are associated with long-term cost savings.

Experience using closed incision negative pressure wound therapy in sternotomy patients

OBJECTIVE

Postoperative delayed wound healing, surgical site infections (SSIs), and other wound complications are associated with increased morbidity and health-care costs. In cardiothoracic surgery, wound complications can have life-threatening consequences. In recent years, negative pressure wound therapy (NPWT) has been applied over closed surgical incisions to help reduce tension and protect from external contamination. We report our initial experiences using a closed incision negative pressure therapy (ciNPT) over clean, closed sternotomy incisions at an Irish tertiary referral centre.

METHOD

A retrospective record review identified 10 patients (4 females, 6 males) where ciNPT was used following sternotomy for cardiac surgery or other mediastinal surgery between January 2012 and March 2013.

RESULTS

The patients had an average age of 71.5±14.18 years (range: 44-89 years). Patient comorbidities included obesity, hypertension, active tobacco use, chronic obstructive pulmonary disease, and diabetes mellitus. Patients underwent coronary artery bypass grafting (CABG), aortic valve replacement (AVR), AVR and CABG, or removal of a thymic mass or mediastinal cyst. ciNPT was left in place for an average of 6±0.82 days. All incisions healed without complications.

CONCLUSION

ciNPT use should be considered for patients at risk for postoperative SSI development or other wound complications.

Management of Surgical Incisions Using Incisional Negative-Pressure Therapy

Use of negative-pressure therapy (NPT) is a well-established therapy for chronic, open, contaminated wounds, promoting formation of granulation tissue and healing. The application of NPT after primary closure (ie, incisional NPT) has also been shown to reduce surgical site infection and surgical site occurrence in high-risk procedures across multiple disciplines. Incisional NPT is believed to decrease edema and shear stress, promote angiogenesis and lymphatic drainage, and increase vascular flow and scar formation. Incisional NPT may be considered when there is a high risk of surgical site occurrence or surgical site infection, particularly in procedures with nonautologous implants, such as hernia mesh or other permanent prosthetics. Here we discuss the proposed physiologic mechanism as demonstrated in animal models and review clinical outcomes across multiple specialties.

Use of Closed-Incision Negative-Pressure Therapy in Aesthetic Surgery

BACKGROUND

Recently published studies have demonstrated clinical effectiveness of closed-incision negative-pressure therapy (ciNPT) in many fields of surgery including vascular, cardiac, colorectal, orthopedic, and reconstructive surgery. A review of current literature was conducted to determine whether the application of negative-pressure therapy to closed incisions post aesthetic procedures was beneficial.

METHODS

The PubMed/MEDLINE databases were searched for preclinical and clinical studies published through June 2018. Higher quality publications that met the following criteria were included: adult patients undergoing aesthetic or body contouring procedures, comparison of ciNPT with conventional dressings, and documentation of wound complications and/or incision quality.

RESULTS

One animal and multiple small, retrospective comparison articles are discussed. Scientific mechanism of action and economic analysis are also discussed. There are no level 1 randomized prospective controlled trials that directly evaluate the effects of ciNPT dressings in cosmetic patients.

CONCLUSION

For patients undergoing certain cosmetic procedures, preliminary data support the idea that ciNPT dressings provide aesthetic benefit, but more research is clearly needed.

Closed-incision negative-pressure therapy decreases complications in ventral hernia repair with concurrent panniculectomy

PURPOSE

Ventral hernia repair with concurrent panniculectomy (VHR-PAN) is associated with high wound complication rates despite reported increased patient satisfaction. Some surgeons believe negative-pressure therapy after primary closure of the surgical incision (ciNPT) may lower wound complications in high-risk abdominal wounds. This study aims to evaluate if ciNPT improves outcomes in patients undergoing VHR-PAN.

METHODS

An 8-year retrospective cohort study was performed on patients who underwent VHR-PAN. Patients were divided into two groups: those who received closed-incision negative-pressure therapy ("ciNPT") and those who received standard sterile dressings ("SSD"). The primary outcome of interest was the rate of postoperative complications between these groups. Complications were subdivided into surgical site occurrences (which included surgical site occurrences that required an intervention), return to the operating room, and hernia recurrence.

RESULTS

A total of 104 patients were analyzed: 62 in the ciNPT group and 42 in the SSD group. Median follow-up duration was similar between both groups (182 days vs 195 days, p = 0.624). Patients in the ciNPT group had fewer total complications (57% vs. 83%, p = 0.004) and fewer SSO (47% vs. 69%, p = 0.025). However, no differences were noted when comparing individual complications (SSI, wound dehiscence, skin necrosis, chronic wound, seroma, and hematoma). There was no difference in return to the operating room (27% vs. 26%, p = 0.890) or hernia recurrence (21% vs 19%, p = 0.811). Multivariate analysis showed that ciNPT decreased the risk of SSOPI nearly fourfold (odds ratio 0.28, 95% CI = 0.09-0.87, p = 0.027).

CONCLUSIONS

This study showed that closed-incision negative-pressure therapy in ventral hernia repair with concurrent panniculectomy may decrease the rate of wound complications in this high-risk population.

The effect of postoperative closed incision negative pressure therapy on the incidence of donor site wound dehiscence in breast reconstruction patients: DEhiscence PREvention Study (DEPRES), pilot randomized controlled trial

AIM

Wound dehiscence is a serious postoperative complication associated both with high morbidity and mortality. It has a significant rate of occurrence in breast reconstruction surgeries with a deep internal epigastric perforator (DIEP) and with a profunda artery perforator (PAP) flap. Risk factors for wound dehiscence include smoking, diabetes mellitus, chronic obstructive pulmonary disease, and obesity. The aim of this pilot study was to assess whether postoperative treatment with closed incision negative pressure therapy (ciNPT) decreases the incidence of donor site wound dehiscence in breast reconstruction patients.

METHOD

Women undergoing a breast reconstruction with a DIEP or PAP flap were enrolled in a pilot randomized controlled trial and assigned treatment with either ciNPT or adhesive strips. The primary outcome was wound dehiscence upon follow-up after four weeks. Secondary outcomes that were evaluated included wound infection, pain, and allergy. There was no loss to follow-up.

RESULTS

This pilot study included 51 women (n = 25 ciNPT, n = 26 adhesive strips). The two groups did not differ significantly in patients demographics or comorbidities. Wound dehiscence occurred in 11 patients (n = 2 ciNPT, n = 9 adhesive strips). This difference was statistically significant: p = 0.038. There were no statistically significant differences in secondary outcomes between the two groups.

CONCLUSION

In this pilot study, postoperative treatment with ciNPT decreased the incidence of donor site wound dehiscence in breast reconstruction patients. Further research is ongoing by the same hospital. This trial was registered in the Netherlands Trial Register (NTR) under ID no. NTR5808.

Closed Incision Negative Pressure Therapy Reduces Surgical Site Infections in Vascular Surgery: A Prospective Randomised Trial (AIMS Trial)

BACKGROUND

Surgical site infections (SSIs) of the groin remain a crucial problem in vascular surgery, prompting great interest in preventative techniques, such as closed incision negative pressure therapy (ciNPT). This prospective randomised study aimed to assess the potential benefits of ciNPT application after groin incisions for vascular surgery.

METHOD

The study included 204 patients who underwent vascular surgery for peripheral artery disease (PAD) at two sites between July 2015 and May 2017. These patients received post-operative treatment with ciNPT (intervention group) or standard wound dressings (control group). After exclusion, 188 patients were assessed for SSIs using the Szilagyi classification.

RESULTS

The mean patient age was 66.6 ± 9.4 years (range 43-85 years), and 70% were male (n = 132). Regarding PAD stage, 52% were stage IIB, 28% stage III, and 19% stage IV. Among the patients, 45% (n = 85) had had a previous groin incision. Bacterial swabs were performed in each case of suspected SSI (22.8% [43/188]), while 76.7% (33/188) were negative, there were 5% [5/98] positive swabs in the intervention group and 5.5% [5/90] in the control group). Antibiotics were given to 13.2% of the intervention group, and 31.1% of the control group (p = .004). The control group experienced more frequent SSIs (33.3%; 30/90) than the intervention group (13.2%; 13/98; p = .0015; absolute risk difference -20.1 per 100; 95% CI -31.9 to 8.2). This difference was based on an increased rate of Szilagyi I SSI in the control group (24.6% vs. 8.1%, p = .0012).

CONCLUSION

The results confirmed a reduced superficial SSI rate after vascular surgical groin incision using ciNPT compared with standard wound dressings.

The Use of Closed Incision Negative-Pressure Wound Therapy in Orthopaedic Surgery

Wound complications and surgical site infections after orthopaedic procedures result in substantial morbidity and costs. Traditional postoperative wound care consists of applying sterile, dry gauze and abdominal pads to the surgical site, with more frequent dressing changes performed in cases in which wound drainage is excessive. Persistent incisional drainage is of particular concern because it increases the risk of deep infection. The use of closed incision negative-pressure wound therapy (ciNPWT) to manage delayed wound healing was first reported a decade ago, and the benefits of this treatment modality include wound contraction with diminished tensile forces, stabilization of the wound environment, decreased edema and improved removal of exudate, and increased blood and lymphatic flow. Numerous trauma, plastic surgery, and general surgery studies have demonstrated that ciNPWT improves wound healing. In orthopaedic surgery, ciNPWT has been shown to be clinically effective for incisions at high risk for perioperative complications. However, specific indications for ciNPWT continue to be defined.

Closed Incision Negative Pressure Therapy Effects on Postoperative Infection and Surgical Site Complication After Total Hip and Knee Arthroplasty

BACKGROUND

The aim of this study is to determine whether negative pressure wound therapy, used prophylactically in clean surgical incisions, reduces surgical site infection, hematoma, and seroma after total joint replacement.

METHODS

A single center, open-label study with a prospective cohort of patients undergoing primary total knee arthroplasty or total hip arthroplasty treated with closed incision negative pressure therapy (ciNPT) of clean surgical wounds was conducted. One hundred ninety-six incisions treated with ciNPT in 192 patients were compared with a historical control group of 400 patients treated with traditional gauze dressing. The rates of clinically significant hematoma, seroma, dehiscence, surgical site infection, and complication were compared using univariate analyses and multiple logistic regression.

RESULTS

The rate of deep infection was unchanged in the ciNPT group compared with control (1.0% vs 1.25%); however, the overall rate of infection (including superficial wound infection) decreased significantly (3.5% vs 1.0%, P = .04). Overall complication rate was lower in the ciNPT group than controls (1.5% vs 5.5%, P = .02). Upon logistic regression, only treatment group was associated with complication; patients treated with ciNPT were about 4 times less likely to experience a surgical site complication compared with control (P = .0277, odds ratio 4.251, 95% confidence interval 1.172-15.414).

CONCLUSION

ciNPT for total knee arthroplasty and total hip arthroplasty in a comprehensive patient population reduced overall incidence of complication, but did not significantly impact the rate of deep infection. Further research to determine clinical and economic advantages of routine use of ciNPT in total joint arthroplasty is warranted.

Effect of a new incision management system (PREVENA®) on wound healing after endophlebectomy of the common femoral vein: a case series

Background

New endovascular techniques facilitate treatment of complex deep vein obstructions in cases of post-thrombotic syndrome. In a relevant number of these patients, endophlebectomy including the implantation of an arteriovenous fistula between the common femoral artery and the femoral vein is indispensable in order to establish a good inflow. These procedures display a high risk of wound complications. Despite conservative efforts to prevent these postoperative complications, wound healing problems occur in more than 20 % of cases. The present case report is the first description of wound dressing using a PREVENA® incision management system in cases of endophlebectomy.

Case presentation

A single center’s experience with the incision management system PREVENA®, which was used after endophlebectomy and venous stenting in complex hybrid procedures in three white men aged 46 years, 53 years, and 61 years is the subject of this case report. Although the surgical procedures were performed under therapeutical anticoagulation and took a couple of hours, no wound complications occurred.

Conclusions

These encouraging results underline a potential benefit of the incision management system PREVENA® in cases of complex venous recanalization including endophlebectomy of the femoral vein as well as the implantation of an arteriovenous fistula.

Closed incision negative pressure therapy: international multidisciplinary consensus recommendations

Surgical site occurrences (SSOs) affect up to or over 25% of patients undergoing operative procedures, with the subset of surgical site infections (SSIs) being the most common. Commercially available closed incision negative pressure therapy (ciNPT) may offer surgeons an additional option to manage clean, closed surgical incisions. We conducted an extensive literature search for studies describing ciNPT use and assembled a diverse panel of experts to create consensus recommendations for when using ciNPT may be appropriate. A literature search of MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials using key words ‘prevention’, ‘negative pressure wound therapy (NPWT)’, ‘active incisional management’, ‘incisional vacuum therapy’, ‘incisional NPWT’, ‘incisional wound VAC’, ‘closed incisional NPWT’, ‘wound infection’, and ‘SSIs’ identified peer‐reviewed studies published from 2000 to 2015. During a multidisciplinary consensus meeting, the 12 experts reviewed the literature, presented their own ciNPT experiences, identified risk factors for SSOs and developed comprehensive consensus recommendations. A total of 100 publications satisfied the search requirements for ciNPT use. A majority presented data supporting ciNPT use. Numerous publications reported SSI risk factors, with the most common including obesity (body mass index ≥30 kg/m²); diabetes mellitus; tobacco use; or prolonged surgical time. We recommend that the surgeon assess the individual patient's risk factors and surgical risks. Surgeons should consider using ciNPT for patients at high risk for developing SSOs or who are undergoing a high‐risk procedure or a procedure that would have highly morbid consequences if an SSI occurred.

Incisional negative pressure wound therapy for high-risk wounds

With an ageing population and a growing number of people with obesity and/or undergoing advanced cancer therapies, there is an increasing risk of surgical site complications including surgical site infections (SSIs). Postoperative shifting of large mobilised tissue flaps, such as in abdominoplasties, remains a dreaded complication, particularly following massive weight loss. Besides negative implications for the patient, surgical site complications result in an economic burden due to prolonged and repeated wound treatments. Preventative tools to reduce SSIs are needed. In selected patients at high risk of SSI and/or wound breakdown, use of incisional NPWT has been shown to actively manage clean, closed surgical incisions. This article contains a review of scientific and clinical research relevant to incisional NPWT use over surgical incisions, with particular emphasis on the common problem of wound breakdown and SSI following body-contouring surgery in post-bariatric patients. Although there are a growing number of studies describing use of incisional NPWT in a variety of applications, including vascular, cardiac and orthopaedic, a literature search revealed few studies regarding incisional NPWT use post body-contouring surgery. In a clinical study of seroma formation, less seroma and haematoma formation was reported in post-bariatric patients who received incisional NPWT, versus the control, following body-contouring surgery. In another study of widely applied external NPWT wound dressings over the ventral and lateral trunk following post-bariatric abdominal dermolipectomy, results showed a significant reduction in exudate formation, earlier drain removal, and decreased length of hospitalisation, compared with conventional treatment. Additional controlled studies are needed to validate the clinical impact of incisional NPWT following body-contouring surgery, and to determine proper recommendations for its use.

Gene expression of catabolic inflammatory cytokines peak before anabolic inflammatory cytokines after ACL injury in a preclinical model

Background

The response of the joint to anterior cruciate ligament (ACL) injury has not been fully characterized. In particular, the characterization of both catabolic factors, including interleukin-6 (IL-6), interleukin-8 (IL-8), and markers of ongoing tissue damage (CRP), and anabolic factors, including vascular endothelial growth factor (VEGF), transforming growth factor β-induced (TGFβI), and the presence of CD163+ macrophages, have not been well defined. In this study, we hypothesized ACL injury would catalyze both catabolic and anabolic processes and that these would have different temporal profiles of expression.

Methods

Adolescent Yucatan minipigs were subjected to ACL transection. Within the joint, gene expression levels of IL-6, IL-8, VEGF, and TGFβI were quantified in the synovium, ligament, and provisional scaffold located between the torn ligament ends at days 1, 5, 9, and 14 post-injury. Macrophage infiltration was also assessed in the joint tissues over the two week period. Serum C-reactive protein (CRP) levels were measured at multiple time points between 1 hour to 14 days after injury.

Results

Increases in IL-6 and IL-8 gene expression peaked at day 1 after injury in the synovium and ligament. CRP levels were significantly increased at day 3 before returning to pre-injury levels. VEGF and TGFβI gene expression did not significantly increase until day 9 in the synovium and were unchanged in the other tissues. CD163+ macrophages increased in the ligament and synovium until day 9.

Conclusion

Taken together, these results suggest that the response within the joint is primarily catabolic in the first three days after injury, switching to a more anabolic phase by nine days after injury. The effect of medications which alter these processes may thus depend on the timing of administration after injury.