Improvement of perineal wound healing by local administration of gentamicin-impregnated collagen fleeces after abdominoperineal excision of rectal cancer

Background: Despite significant advancements in rectal surgery, poor perineal wound healing after abdominoperineal resection (APR) of the anorectum continues to be a potential complication of the procedure. The aim of this prospective randomized multicenter study was to investigate the efficacy of a new mode of local antibiotic administration. Patients and methods: Ninety-seven patients who had to undergo APR for low rectal carcinoma either received sacral drainage plus primary wound closure (control group, N = 48) or the same treatment and supplementary application of three resorbable gentamicin-impregnated collagen fleeces (Septocoll; Merck Biomaterial GmbH, Darmstadt, Germany; Genta group, 49). The following target criteria were investigated: bacteriologic efficacy with respect to the eradication of Enterobacteriaceae, Staphylococcus, and Pseudomonas organisms, and clinical efficacy with respect to perineal wound healing. Results: The Genta group showed a marked reduction in the investigated pathogens from the secretion obtained by sacral drainage on days 1 and 3, as well as high gentamicin concentrations (day 1, median 126.2 μg/mL; day 3, median 97.6 μg/mL). In total, bacteriologic efficacy amounted to 83.7% in the Genta group (41 of 49 patients) versus 60.4% (29 of 48 patients) in controls (P = 0.013). In concurrence with these bacteriologic results, the postoperative infection rate was significantly higher in controls: 10 patients (20.83%) in the control group versus 3 (6.1%) in the Genta group developed perineal or sacral infection (P <0.05). Postoperative complications in the recruited patients revealed no indication of gentamicin-induced adverse reactions. Conclusions: The results of the study show that the specified dose of 3 Septocoll fleeces in patients with APR is liable to significantly eliminate enterobacteria, staphylococci, and pseudomonads. The clinical course is improved as a result of the bactericidal effect exerted by the gentamicin fleece. The use of Septocoll reduced the incidence of postoperative perineal and sacral infections. Local antibiotic carriers seem to be of great advantage in poorly perfused areas such as the sacral cavity or anatomically problematic regions as the rima ani. In locally contaminated or infected areas, local antibiotic carriers achieve greater concentrations of the active substance than those achieved with systemic antibiotics, even if the latter are administered by the parenteral route.