Prophylactic closed-incisional negative pressure wound therapy following posterior instrumented spinal fusion: a single surgeon's experience and cost-benefit analysis

Purpose: Surgical site infections (SSIs) following spine surgery are associated with morbidity and resource utilization. Applying prophylactic closed-incisional negative pressure wound therapy (ciNPWT) during posterior instrumented fusion has mixed results in reducing rates of wound complications and SSI. We evaluated the clinical efficacy and potential cost-savings associated with ciNPWT in high-risk patients receiving posterior instrumented spinal fusion. Methods: We retrospectively reviewed patients receiving posterior instrumented spinal fusion for any surgical indication between July 1, 2017 and December 31, 2019, and compared rates of wound dehiscence, SSI, and reoperation for wound complications between standard surgical dressings and ciNPWT. Surgical dressing selection was based on the senior author's assessment of infection risk factors. Results: A total of 229 patients (n = 85 standard surgical dressings, n = 144 ciNPWT) were included. The ciNPWT group had significantly more risk factors for wound-related complications, including older age (61.8 vs. 58.5 years, p = 0.042), diabetes mellitus (36.8% vs. 23.5%, p = 0.037), more instrumented levels (5.6 vs. 3.9, p < 0.0001), estimated blood loss (1298 vs. 998 mL, p = 0.036), and deformity was the predominant operative indication (29.9% vs. 17.7%, p = 0.040). Prophylactic ciNPWT was associated with significantly lower rates of wound dehiscence (21.5% vs. 34.1%, p = 0.036) and SSI (8.3% vs. 21.2%, p = 0.005). Number needed to treat with ciNPWT to prevent one SSI was 8 patients. The cost of preventing one SSI was $4,560. Cost-benefit analysis demonstrated a potential mean savings of $21,662 per operative SSI prevented and $270,775 per 100 patients undergoing posterior instrumented fusion with ciNPWT. Conclusions: Prophylactic ciNPWT use is a cost-effective means of reducing rates of wound dehiscence and SSI following posterior instrumented fusion.