Objectives To assess the incidence of postoperative infectious morbidity (POIM) after cytoreductive surgery (CRS) in advanced ovarian cancer (AOC) patients and utilization of pre-operative stool surveillance culture in prediction of antimicrobial resistance (AMR) and treatment of POIM.

Methods Retrospective observational study in FIGO stage III/IV AOC patients operated between 2015 to 2018 at Tata Medical Center, Kolkata, India. Data was extracted from hospital electronical medical records.

Results Out of 328 patients operated, pre-operative stool culture report was available in 225 women. Multidrug resistant organisms (MDRO) was isolated in 177 (78.6%); E Coli (n=136), Klebsiella (n=48), Enterobacter (n=40), Psedomonas (n=2), Acinetobactor (n=1). E.Coli was the major organism isolated in blood stream, urine and body fluid in patients with POIM (60%). Clinical/Microbial confirmed POIM was diagnosed in 107/225 (47.5%) women up to 30 days post-operatively; Clavien-Dindo(CD)2 in 88, CD3 in 12, CD4 in 5 and CD5 in 2 women. AMR pattern in MDRO: Amoxiclavulanate (90%), Piperacillin-Tazobactam(50–60%), Meropenem (30–40%) and Colisitn and Fosfomycin (0–5%) making Meropenem the most commonly prescribed antibiotic for POIM. In multivariate analysis, Diabetes Mellitus (OR 3.0,CI 1.3–7.0) and Bowel resection (OR4.4, CI 2.2–9.8) were independent risk factors for POIM(p<0.05), while splenectomy and diaphragmatic surgery was significantly associated in univariate analysis.

Conclusions CRS in AOC was associated with high incidence of POIM at our setting; pre-operative surveillance stool culture could guide us in starting the appropriate antibiotic post-operatively at the earliest clinical suspicion based on the MDRO profile. Although, the treatment cost is high, > 80% women go home around the 7th post-operative day.