Long-Term Results of Vascular Graft and Artery Preserving Treatment With Negative Pressure Wound Therapy in Szilagyi Grade III Infections Justify a Paradigm Shift

Abstract

Szilagyi III infections are safely and effectively treated both short and long term with negative pressure wound therapy (NPWT). Wound infections with prosthetic graft or arterial involvement (Szilagyi grade III infections) can be associated with high morbidity and mortality (Kikta MJ et al. J Vasc Surg 1987;5:566-71). Traditional treatment for Szilagyi III infections is graft excision, radical debridement and secondary vascular reconstruction. NPWT was introduced in 1997 by Argenta and Morykwas (Morykwas MJ et al. Ann Plast Surg 1997;33:553-62). There have been small series of patients with vascular graft infections treated by NPWT without graft excision with apparently good short term results (Dosluoglu HH et al. J Vasc Surg 2010;51:1160-6). In this paper the author's report their short and long term results of NPWT for treatment of vascular infections with a mean follow up of 43 months. There were 44 patients (mean age 62 years) with Szilagyi III infections treated with NPWT from 2002 to 2009 and 13 of the 44 required intensive care unit admission. There were 40 grafts (prosthetic, 24; vein, 3; biologic, 13) and 9 native arteries involved with infection. NPWT (VAC; KCI International, Amstelveen, The Netherlands) was applied directly to grafts and arteries using negative pressures from 50 to 125 mm Hg. VAC therapy was instituted after radical debridement of infected tissue. Antibiotics were used according to culture information. The median duration of NPWT was 33 days (IQR, 20-78). Median hospitalization was 32 days (IQR, 20-82) days. There were no deaths within 30 days and one-year mortality was 16%. After a mean follow up of 43 months long term mortality was 41% (18/44). Only one of the 18 deaths was related to graft infection. Complete wound healing was achieved in 91% and 37 of 44 grafts were preserved without long term reinfection. There were no significant positive predictors for mortality. Patients presenting with early infection had a negative association for reinfection (OR, 0.17; 95% CI, 0.03-1.07; P = .03). Patients presenting with late infection had a positive association with reinfection (OR, 5.73; 95%CI, 0.93-39.1; P = .03). Amputation was also a strong predictor of reinfection (OR, 7.94; 95%CI, 1.02-72.5; P = .24). There is no universally accepted management for wound infection that involves prosthetic grafts, vein grafts, or native arteries. The results here using NPWT therapy are encouraging. There was only one graft related death. VAC therapy has revolutionized care of open wounds in recent years. Through a combination of antimicrobial activity, stimulation of granulation tissue, and increased local perfusion, it appears VAC therapy can create an environment suitable to combat infection. The author's implication that the results of NPWT for Szilagyi III infections justify a paradigm shift in the management of vascular graft infections just may be true.