Association of Negative Pressure Wound Therapy and Dermatotraction for Management of Necrotizing Soft Tissue Infections: A Case Series

Introduction. Soft tissue infections (STIs), which include infections of the skin, subcutaneous tissue, fascia, and muscle, encompass a wide variety of heterogeneous pathologies. Treatment of STIs is based on surgical debridement of the affected area. One such treatment, negative pressure wound therapy (NPWT), has improved the management of STIs. Objective. The purpose of this study is to assess the safety and utility of NPWT in conjunction with dermatotraction in the early stage management of necrotizing STIs. Materials and Methods. The authors report a retrospective series of 3 cases in which NPWT and dermatotraction (NPWT-D) were used in an attempt to manage necrotizing STI. The NPWT-D device combination was employed to approximate the edges of the wounds. The NPWT device was changed every 2 or 3 days, and dermatotraction tension was adjusted concurrently. Results. The NPWT-D device changes ranged from 3 to 4 times for 2 of the 3 patients, as 1 patient passed away secondary to STIs and therefore did not receive complete treatment. The total treatment ranged from 8 to 10 days in the remaining 2 patients. In both cases, complete wound closure was achieved while avoiding skin grafts. After 5 days of therapy in the incomplete treatment case, the wound area was reduced by about half. Conclusions. Based on the experiences herein, NPWT-D may be a safe and useful alternative surgical treatment for the management of necrotizing STIs. In the present cases, NPWT-D improved and shortened the wound healing process, and it achieved a tertiary wound closure, thereby avoiding the need for skin grafts.

Soft tissue infections (STIs), which include infections of the skin, subcutaneous tissue, fascia, and muscle, encompass a wide variety of heterogeneous pathologies. The necrotizing STI subgroup (cellulitis, fasciitis, and myositis) has high mortality rates, reaching 14% to 22% despite appropriate treatment (extensive surgical debridement, intravenous antibiotics, and intensive care unit [ICU] support).¹ Early diagnosis must occur in order to prevent aggressive surgical debridement, which usually results in wide tissue defects that may require skin grafts or flaps to achieve closure. 

A growing body of evidence^2-4 has reported the positive effects of negative pressure wound therapy (NPWT) in complex wounds; these positive effects include a decreased time interval until tertiary wound closure and reduced chance of needing skin grafts or flaps. Despite successful testing in necrotizing STIs,^2,4 its application is controversial for the following reasons: the role of NPWT regarding bacterial loads,⁵ impossibility of visualizing the wound background, and assessing progression of the STIs and the absence of cost-effectiveness studies. The direct effects of NPWT include maintaining optimal and stable humidity and temperature conditions, draining secretions, reduction of interstitial edema, and improvement of the wound’s microenvironment due to the removal of excess proteases.³ The indirect effects of NPWT include increased blood flow (input of oxygen and nutrients), decreased inflammatory response and bacterial load, and increased granulation tissue by overexpression of vascular endothelial growth factor.³

Dermatotraction therapy is based on the elastic properties of the skin.² Injury of the cutaneous wound edges where the traction elastics are anchored in dermatotraction devices has been reported.⁴ 

The purpose of this study is to assess the safety and utility of NPWT in conjunction with dermatotraction (NPWT-D) in the early stage management of necrotizing STIs.

The authors report a series of 3 cases involving the application of NPWT-D for the management of necrotizing STIs from December 2018 to March 2019. The diagnosis was based on clinical suspicion, the “finger test,” and Laboratory Risk Indicator for Necrotizing Fascitis (LRINEC) scale, in which a score of 6 or more indicates an intermediate to high risk (Table 1).⁶ The finger test comprises a small incision on the suspected area under local anesthesia and direct visual examination of the tissue. The absence of normal blood flow, dirty dishwater-colored fluid, and discoloration of the fatty tissue favor the STI diagnosis.⁷ Early imaging tests were not performed as they are not useful in excluding the presence of necrotizing STI.

Of note, NPWT-D required the following materials: NPWT system (SIM^EX200; SIMEX Medizintechnik GmbH) with the SIMEX PU NPWT foam dressing and sponge set (sponge, transparent dressing, and suction system), vessel loops (Medi-Loops; Medline Industries), and staples. It is mandatory to perform the technique under sterile conditions.

Before NPWT-D was performed, all 3 patients underwent an appropriate aggressive debridement. In 2 cases (patients 1 and 2), NPWT-D was performed immediately after debridement. In patient 3, NPWT-D was performed 9 days after initial debridement (due to aspiration pneumonia).

First, the foam sponge was adapted to the wound size and placed on the wound. Dermatotraction was performed using a “shoelace” technique. The ends of 2 knotted vessel loops were fixed at the vertex of the wound. The elastics were fixed to the edge of the skin in an interrupted manner, with staples diagonally, from one edge of the skin to the other, at intervals of 1.5 cm to 2 cm until reaching the other vertex of the wound, where these were knotted and fixed with staples. Finally, the transparent insulating dressing and the foam dressing set suction system were placed and connected to the NPWT device that was set to maintain a continuous negative pressure of -120 mm Hg (Figure 1). The wound was checked and NPWT device was changed every 2 or 3 days (although depending on the patient’s condition, this revaluation can be advanced between 12–48 hours in general) and dermatotraction tension was adjusted concurrently until achieving a tertiary closure.

The mean patient age was 54 years, and there were 2 females. At their arrival to the emergency department, the patients presented with the vital signs and laboratory data seen in Table 1. In 2 of the patients, an open trauma injury as inoculation point was diagnosed. In the other patient, no entrance door was identified. In all 3 cases, a definitive pathological diagnosis of necrotizing cellulitis without fasciitis or myositis was reached.

All of the patients had a LRINEC score greater than 4 (ie, 2 patients in the intermediate risk category, 1 in the low risk category). The 3 patients underwent surgical debridement with a maximum delay of 6 hours from their arrival at the emergency department. In 2 of the cases, NPWT-D was performed after the first debridement. The required pharmacological and surgical treatment is shown in Table 2. Average stay in the ICU was 10 days, and the mean total hospital stay was 17 days.

The mean interval between NPWT-D device changes was 3 days. All patients required an average of 4 device changes, and the mean NPWT-D length was 7 days. The initial wound surface areas were 675 cm², 1200 cm², and 450 cm² in patients 1, 2, and 3, respectively. In the second case, definitive closure was not achieved due to the death of the patient; the wound defect at death was 670 cm². The patient death was related to multiple organ failure associated with STIs. Mortality was 33% (1 patient). The other 2 patients presented with seroma of the surgical wound that was managed with non-surgical treatment. Patients were discharged at postoperative days 27 (patient 1) and 12 (patient 3).

At the 10-month follow-up visit, patient 1 presented with a seroma managed with a conservative approach and deformation of the ipsilateral breast (Figure 2). The case of the deceased patient (patient 2) is documented in Figure 3. Patient 3 presented a partial dehiscence of the skin wound (Figure 4). 

When NPWT-D was performed immediately after the first debridement, positive effects were noted in the present cases. No adverse events (hemorrhages, infections, local complications) were registered. The NPWT-D device accelerated wound closure and prevented the need for skin grafts in these patients.

The placement of the system was easy to both apply and replicate. It took about 30 minutes to perform each NPWT-D device change. Due to the general need for thorough revaluation and subsequent debridement of these wounds, it is vital to plan an appropriate schedule of NPWT-D device changes. They should be considered closer in time than standard NPWT device changes. Basic hemodynamic monitoring and evaluation (a focused physical examination and static hemodynamic vital signs [temperature, heart rate, respiratory rate, mean arterial pressure, and arterial hemoglobin oxygen saturation]) may improve the prognosis of these patients and the results of NPWT-D. 

The low incidence of this pathology and the heterogeneity of its clinical presentation hinder to conduct studies with appropriate sample size and statistical significance. As such, a limitation of this study is the small sample size. A multicenter study is necessary to confirm the positive role of NPWT-D in the management of necrotizing STI management.

Based on the experiences herein, NPWT-D may be a safe and useful alternative surgical treatment for the management of necrotizing STIs. In the present cases, NPWT-D improved and shortened the wound healing process, and it achieved a tertiary wound closure, thereby avoiding the need for skin grafts. 

Authors: Daniel Aparicio-Sánchez, MD, PhD¹; José Pintor-Tortolero, MD, PhD¹; Eduardo Perea-Del Pozo, MD, PhD¹; Luis Tallón-Aguilar, MD, PhD¹; and Francisco Javier Padillo-Ruiz, MD, PhD² 

Affiliations: ¹Emergency Surgery Unit, Virgen del Rocío University Hospital, Seville, Spain; and ²General Surgery Unit, Virgen del Rocío University Hospital

Correspondence: Daniel Aparicio-Sánchez, MD, PhD, Servicio de Cirugía General y del Aparato Digestivo, Hospital Universitario Virgen del Rocío, Avda
Manuel Siurot s/n CP 41013 Sevilla, Spain; daniel.apariciosanchez@gmail.com

Disclosure: The authors disclose no financial or other conflicts of interest.