Multivariate analysis of risk factors for surgical site infection after laparoscopic colorectal surgery

Surgical site infection (SSI) and incisional hernia (IH) are among the most common complications after colorectal surgery. While many risk factors for these complications are unavoidable, evidence suggests that use of Pfannenstiel incisions for specimen extraction during laparoscopic procedures may reduce their incidence. The objectives of this study were to identify risk factors for extraction site SSI (primary objective) and IH (secondary objective) in patients undergoing laparoscopic colorectal surgery.

Patients who underwent laparoscopic colorectal resections at The Ohio State University Wexner Medical Center between January 2006 and October 2012 were included. In addition to reviewing medical records, data were gathered from patient questionnaires with a focus on two end points: extraction site SSI and IH. Univariate logistic regression analysis was performed to identify significant associations between the two end points and the following variables: age, gender, ASA (American Society of Anesthesiologists) score, cancer, inflammatory bowel disease (IBD), body mass index (BMI), diabetes, chronic obstructive pulmonary disease, use of immunosuppressant medications, chemotherapy, radiation therapy, smoking, surgical history, surgery duration, duration of follow-up, use of hand-assistance, and utilization of Pfannenstiel incisions for specimen extraction. Multivariate analysis was performed for significant variables.

A total of 419 patients met the inclusion criteria. The incidence of SSI was 10.3%. Higher BMI, presence of IBD, younger age, and hand-assisted procedures were associated with a significantly higher risk of SSI. Use of Pfannenstiel extraction sites was associated with lower infection rates; however, this association was not statistically significant. IBD, BMI, and hand-assistance were statistically significant on multivariate analysis. Odds ratios for SSI with IBD, hand-assistance and BMI (per unit increase) were 3.3, 2.2, and 1.06, respectively.

Alterations in surgical technique and specimen extraction site can reduce wound-related complications after laparoscopic colorectal resections. Remaining risk factors are largely nonmodifiable from a surgeon's perspective.