Role of Negative Pressure Wound Therapy in the Management of Complex Wounds of Lower Limb

Abstract

Background: Complex wounds are characterized by extensive loss of skin and soft tissue, often exposing tendons, bones, or implants, and are classified based on criteria such as chronicity, infection, compromised tissue viability, and association with systemic pathologies. Treatment traditionally involved moist gauze therapy but has evolved with the introduction of Vacuum Assisted Closure (VAC) or Negative Pressure Wound Therapy (NPWT), offering controlled sub-atmospheric pressure to enhance wound healing by removing excess fluid, promoting circulation, and converting open wounds into controlled, closed ones.

Methodology: The study, conducted at the Government Institute of Medical Sciences in Greater NOIDA from August 2019 to March 2021, investigated the effectiveness of Negative Pressure Wound Therapy (NPWT) in managing complex lower limb wounds. Involving 42 patients with exposed wounds and implants, the research applied NPWT using a vacuum pump and recorded dimensions at presentation, patient response, and the time taken for healthy granulation tissue formation. The NPWT dressing system included a polyurethane pack, vacuum pump, canister, and tubes, while microbiological examination and surgical procedures were performed for comprehensive wound management.

Results: Among the 42 patients, the majority (59.5%) were in the 46-55 age group, with 33.3% in the 35-45 age group and 7.1% in the 25-35 age group. The predominant aetiologies included eight cases of necrotising fasciitis, six traumatic ulcers, and five cellulitis cases. Patients with diabetes mellitus comprised 38% of cases, and the mean wound area significantly decreased from initiation (159.57 mm) to completion (114.5 mm) of NPWT. Wound scoring also significantly improved, and closure was achieved in 52.4% of patients with split-thickness skin grafting. Bacterial clearance notably improved with NPWT, reducing the contamination rate from 98% to 57.1%. The mean duration of hospital stay was 35.35 days, with an average cost of 44091 INR. The study had limitations, such as the sample size, suggesting the need for larger randomized controlled trials for further insights.

Conclusion: NPWT is highly effective in managing complex wounds, promoting improved microcirculation, rapid formation of healthy granulation tissue, reducing the need for frequent debridement and early wound cover. The study also demonstrates the efficacy of NPWT in promoting healing by secondary intention in complex lower limb wounds, and despite the high cost of dressing, the overall reduction in dressing frequency, debridement’s, and hospital stay results in a reduction in the ultimate financial burden.

Keywords: Complex wound, Negative Pressure Wound Therapy, Vacuum Assisted Closure (VAC), Wound dressings