O08 – Obstructive sleep apnea: a risk factor for surgical site infection after colectomy
Author(s):
Background: Obstructive sleep apnea (OSA) has not previously been identified as a risk factor for surgical site infection (SSI). OSA is associated with increased systemic oxidative stress, endothelial dysfunction and activation of pro-inflammatory cascades.
Hypothesis: OSA is a risk factor for SSI after colectomy.
Methods: We retrospectively reviewed data from all colectomies performed at the University of Minnesota Medical Center from August 2011 to September 2013 and indentified patients with OSA undergoing colectomy. We matched patients with OSA to those without from the population of patients undergoing colectomy, with patient groups matched for age, body mass index (BMI), sex, open surgery, procedure time, diabetes mellitus (DM) and reason for surgery (e.g. cancer, inflammatory bowel disease or infection). Multivariate logistic regression and ANOVA were performed when appropriate.
Results: Forty two patients with preexisting OSA were identified from a total of 502 colectomies over the included time period. We matched these 42 patients to 68 patients from this population without OSA. The rate of SSI was 28.6% among the patients with OSA while the SSI in the control group was only 10.3% (p=0.019). Compared to matched controls, multivariate regression analysis revealed the following risk factors for SSI: OSA (odds ratio [OR], 5.4; 95% confidence interval [CI], 1.19-24.58; p = 0.028), and DM (OR, 12.7; 95% CI, 2.08-77, p = 0.005). Age, BMI, sex, type of surgery and reason for surgery were not associated with an increased risk for SSI. OSA was associated with longer hospital stay in patients with SSI, but not in those that did not develop SSI (figure).
Conclusions: OSA is an independent risk factor for SSI and is associated with longer hospital stay in patients that developed SSI after colectomy.