Negative Pressure Wound Therapy Compared to Petrolatum Gauze and a Bogota Bag to Manage Postoperative Midline Abdominal Wound Dehiscence: A Pilot, Nonrandomized Controlled Trial

Abstract

A study was conducted to evaluate the efficacy of NPWT for fascial closure/cutaneous cover compared to non-NPWT treatment using petrolatum gauze and a Bogota bag in patients with postoperative laparotomy wound dehiscence. A single center, prospective, nonrandomized pilot study was conducted. Using convenience sampling methods, consecutive patients on 6 different surgical units who were at least 18 years of age and who developed postoperative abdominal wound dehiscence following elective and emergency laparotomy from January 2017 to December 2018 were recruited. NPWT dressing with polyvinyl white foam sponge or loosely packed, saline-soaked petrolatum gauze followed by Bogota bag application were used and compared. Baseline patient demographics and history were collected, and patients were followed for an average of 6 months after surgery. Number of days until first signs of granulation tissue appearance, time until complete granulation tissue cover/fascial surgical closure, and hospital discharge were compared. Categorical variables (gender, comorbidities, presence or absence of stoma, exposure to prior radiotherapy) were expressed as proportions and analyzed using chi-squared test or Fischer's exact test. Continuous variables such as age, body mass index, albumin, postoperative hospital stay, and number of days required for decision for fascial closure were expressed as Mean ± standard deviation and analyzed using an independent t test or Mann Whitney U test based on whether the data followed normal distribution. Postoperative day of wound dehiscence, the number of days for the appearance of granulation tissue, and the number of NPWT placements required also were assessed using Mean ± standard deviation and analyzed using an independent t test. A P value <.05 was considered significant. Sixty (60) patients were included, but 4 in NPWT group and 10 in the non-NPWT group could not complete the study, leaving 26 patients in NPWT group and 20 patients in non-NPWT group. Demographic and surgical variables were not significantly different. Patients in both groups achieved complete wound coverage by surgical closure or healing by secondary intention. Days until first signs of granulation tissue (2.92 vs. 6.65; P <.001), number of days until fascial closure (15.50 vs. 29.50; P <.001), and length of postoperative hospital stay (24.30 vs. 37.90; P <.001) were significantly less in NPWT group. Two (2) patients (7.6%) in the NPWT developed a fistula during the 6-month follow-up period. No fistulas developed in the control group, and no intra-abdominal abscesses, ventral hernias, or wound dehiscence were reported in either group. Time until first signs of granulation tissue appearance and complete granulation tissue coverage was significantly shorter in the NPWT group, but time until definitive closure was not evaluated. Randomized, controlled clinical studies to compare definitive time to wound closure and long-term follow up to evaluate long-term complication rates, including the risk of developing fistulas, are warranted.