Background:

Postoperative bariatric surgery (BS) infection rates (IRs) of 1%‐16.5% have been reported, with a mortality rate of up to 21.7%. This study investigated the 30‐day postoperative IR and mortality rate at our institution. It also examined epidemiologic risk factors for postoperative bariatric surgery infections.

Methods:

Nosocomial infections that occurred less than 30 days post‐BS at our institution over 6 years were retrospectively reviewed (1 month follow‐up rates of at least 95.4%). Surgical site infection was defined according to the National Nosocomial Infections Surveillance System (NNIS) criteria. Data were collected on all patients with culture‐positive infections. A case‐control study with 70 cases and 280 randomly selected controls was conducted to assess the association of post‐BS infection with age, sex, race/ethnicity, diabetes mellitus (DM), hypertension (HTN), and smoking.

Results:

During the period reviewed 4704 bariatric surgeries were performed, of which 74.6% were open gastric bypass (GB) and 25.4% were laparoscopic (LB). Seventy cases (1.5%) with infection were reported — 30 superficial abdominal (42.9%), 12 deep abdominal (17.1%), and 28 intra‐abdominal (40.1%). Mean age of the patients was 49.6 ± 8.9 years, 64.3% were female, and 84.3% were white; mean BMI was 52.6 ± 7.9, 30% had diabetes, 60% were hypertensive, and 15.8% were smokers. Regarding NNIS risk score, 88.6% of the cases and 58.9% of the controls (uninfected) had a risk score of 1, and 11.4% of the cases and 16.6% of the controls had a risk score of 2 (P = .03). Only 2 cases underwent LB bariatric surgery. All patients received local and systemic antibiotics prior to BS. The most commonly cultured organisms were Staphylococcus aureus (52.9%), streptococcus (21.4%), corynebacterium (14.3%), enterococcus (11.4%), and Proteus mirabilis (11.4%). Forty‐one cases (58.6%) had incision and drainage, 25 (35.7%) exploratory laparotomy, and 2 (2.9%) acute respiratory distress syndrome. Infection‐related mortality was 2.9% (n = 2), and overall mortality was 0.04%. Mean length of hospital stay for cases was 6.71 days versus 3.09 days for uninfected (control) patients. There was a significant association of length of stay with age (P = .04) and HTN (P = .01) in the linear regression model. A multiple logistic regression model showed that those who were elderly (adjusted OR = 1.08, 95% CI: 1.04‐1.11, P < .0001) and those who were male (adjusted OR = 0.45, 95% CI: 0.25‐0.80, P = .006) were significantly more likely to develop post‐BS infections.

Conclusions:

Hospitalists play a key role in the perioperative management of BS; hence, knowledge of factors involved in postoperative infections is imperative. Thirty‐day IR (1.5%) and infection‐related mortality (2.9%) after BS were low at our institution, possibly because of the low NNIS risk scores (58.9% had a score of 1), compliance with preoperative local and systemic antibiotics, a no‐shave policy, and surgical expertise. In our case‐control analysis, only age and sex had a statistically significant association with post‐BS infections; history of DM, HTN, and smoking did not.

Author Disclosure:

R. Sahni, None; P. Sharma, None; N. Rohatgi, None; R. Chmielewski, None.