Cost analysis of negative-pressure wound therapy versus standard treatment of acute conflict-related extremity wounds within a randomized controlled trial

The design and clinical outcomes of the randomized controlled trial have been described in detail elsewhere [7, 8]. Briefly, 165 adult (≥ 18 years) patients with acute (≤ 72 h) conflict-related extremity wounds were enrolled from June 9, 2015, to October 24, 2018, at two civilian hospitals in Jordan and Iraq. Participants were randomly assigned to NPWT (n = 83), involving a commercial NPWT device with a continuous negative pressure of 125 mm Hg, or standard treatment (n = 82), involving wound dressings with non-adhesive sterile gauze covered with a bandage. Dressings were changed in the operating theatre every three to five days, in accordance with the International Committee of the Red Cross war surgery protocol [10]. The primary outcome was wound closure by day five. Data on wound closure were collected at each dressing change, at hospital discharge, and at days 14 and 30 following the day of randomization. Wound closure was defined as closure by suture, flap, or split-thickness skin graft. A coprimary endpoint, net clinical benefit, was used, defined as a composite of wound closure by day five, and freedom from any bleeding, wound infection, sepsis, or amputation of an index limb. Health outcome data from both study sites were used for the present study.

The cost analysis was undertaken from the perspective of the healthcare provider [11]. Costs were either related to surgeries or to the care given on the ward and included the following items: medicines and materials, staff costs, overhead costs, and capital costs (Table 1). A surgical procedure was defined as any intervention that occurred in the operating theatre, including wound dressing changes. Wound dressing changes were not performed on the ward. The cost per surgical procedure was calculated based on the total number of surgeries per year. Costs for postoperative care on the ward were calculated as cost per 24 h, based on the yearly costs for all admitted patients divided by the yearly number of patient-days on the ward.

The Iraqi site, where information was readily available to the study team, provided cost data. During 2017, the Iraqi hospital provided a total of 6169 patient days and 2210 surgeries, exclusively for patients with acute conflict-related injuries. Costs for the treatment of chronic wounds (defined as non-closure within 30 days) were not included in the analysis. All NPWT equipment was bought for the purpose of this study. Local costs were converted to average 2019 US dollars.

To assess the robustness of the findings, a sensitivity analysis was performed. The surgical productivity level was modified by − 20% and by + 20%, and staff costs were modified by − 50% and by + 50%. To assess the effects of a rural hospital setting, rental costs were modified by − 50%. The cost for NPWT pumps used in this study was lower than standard costs in high-resource settings. Thus, the capital cost for the NPWT pumps was modified by + 100%.

We analyzed data using R version 3.5.0 software [12].

The cost per surgery was $329 in the NPWT group and $250 in the standard treatment group. The cost per day spent at the hospital was $116 and $109 in the NPWT and standard treatment groups, respectively. The mean patient cost for the full hospital period was $3118 in the NPWT group and $2976 in the standard treatment group (Table 2). Consequently, the use of NPWT was associated with an additional $142 (5%) per treated patient compared to standard treatment (Fig. 2).

Table 3 shows a sensitivity analysis of mean patient costs using NPWT and standard treatment. While some changes did occur with respect to the mean difference in cost, patients allocated to NPWT had consistently higher costs.