Risk factors and outcomes of organ-space surgical site infections after elective colon and rectal surgery

Abstract

BackgroundOrgan-space surgical site infections (SSI) are the most serious and costly infections after colorectal surgery. Most previous studies of risk factors for SSI have analysed colon and rectal procedures together. The aim of the study was to determine whether colon and rectal procedures have different risk factors and outcomes for organ-space SSI.MethodsA multicentre observational prospective cohort study of adults undergoing elective colon and rectal procedures at 10 Spanish hospitals from 2011 to 2014. Patients were followed up until 30 days post-surgery. Surgical site infection was defined according to the Centers for Disease Control and Prevention criteria. Oral antibiotic prophylaxis (OAP) was considered as the administration of oral antibiotics the day before surgery combined with systemic intravenous antibiotic prophylaxis.ResultsOf 3,701 patients, 2,518 (68%) underwent colon surgery and 1,183 (32%) rectal surgery. In colon surgery, the overall SSI rate was 16.4% and the organ-space SSI rate was 7.9%, while in rectal surgery the rates were 21.6% and 11.5% respectively (p < 0.001). Independent risk factors for organ-space SSI in colon surgery were male sex (Odds ratio -OR-: 1.57, 95% CI: 1.14–2.15) and ostomy creation (OR: 2.65, 95% CI: 1.8–3.92) while laparoscopy (OR: 0.5, 95% CI: 0.38–0.69) and OAP combined with intravenous antibiotic prophylaxis (OR: 0.7, 95% CI: 0.51–0.97) were protective factors. In rectal surgery, independent risk factors for organ-space SSI were male sex (OR: 2.11, 95% CI: 1.34–3.31) and longer surgery (OR: 1.49, 95% CI: 1.03–2.15), whereas OAP with intravenous antibiotic prophylaxis (OR: 0.49, 95% CI: 0.32–0.73) was a protective factor. Among patients with organ-space SSI, we found a significant difference in the overall 30-day mortality, being higher in colon surgery than in rectal surgery (11.5% vs 5.1%, p = 0.04).ConclusionsOrgan-space SSI in colon and rectal surgery has some differences in terms of incidence, risk factors and outcomes. These differences could be considered for surveillance purposes and for the implementation of preventive strategies. Administration of OAP would be an important measure to reduce the OS-SSI rate in both colon and rectal surgeries.

Prevalence and risk factors for surgical site infection after colorectal surgery: a multiple-center prospective study of 3,663 consecutive patients in China

“…They might be selected on the basis of indications for operation, and surgeons might also tend to avoid invasive techniques in treating older individuals. ASA score has been confirmed as an independent risk factor of SSI in a few studies [6,16,35], but this association could not be detected in some other surveys [5,18,19,36]. The present data indicated the ASA score more than 2 was a predictive factor in SSI in CRS by the univariate analysis, whereas, not confirmed in the multivariate analysis.…”

“…Besides, longer preoperative hospital stay may also increase patients' risks in developing SSIs by contacting with medical environment or personnel and colonization by microorganisms [34]. Some studies reported that emergent operation was associated with higher rate of SSI after CRS [6,36], and longer surgery duration was an independent risk factor for development of SSI in CRS [16,19,36]. Nevertheless, neither of these factors were confirmed in our data, despite that increasing susceptibility of SSI was detected, whereas, not statistically significant.…”

“…NNIS risk index has been proved to be an useful tool to assess the risk of developing SSI and widely used to adjust the risk of SSI for the comparison among different institutions or surgeons [28][29][30]. In our survey, the risk of SSI after colorectal operations was found to increase as the NNIS risk index score increased like other studies [6,19], and SSI rates stratified by NNIS index were similar to the corresponding U.S. NNIS rates [31]. Patientdependent variables had little effect on the prevalence of SSI in our study.…”

“…Older than 60 years, male sex, multiple procedures and preoperative hospital stay ≥ 48 h also exhibited a tendency to develop SSI, as their P values were less than 0.2. [19,20] only reported complex SSI rates in CRS which, to some extent, explained the disparities.…”

“…Patientdependent variables had little effect on the prevalence of SSI in our study. Age was reported to be a significant risk factor in few of the other operative procedures [32], but not in CRS [15,16,19,[33][34][35].…”