Abstract
INTRODUCTION: Preserving sterility and safety in hospital operation theaters (OTs) is vital. We have implemented a comprehensive microbiological surveillance program for OTs, encompassing both commencement and ongoing monitoring. This study assesses the prevalence of microorganisms, identifies their types, and detects contamination on surfaces and in the air. METHODS: Commencement and monitoring samples were collected from October 2021 to July 2023, from nine OTs. OTs were cleaned with soap and water, disinfected, and fogged with quaternary ammonium compounds. After sealing the OTs overnight, samples were collected aseptically. Air was sampled using the settle plate method, and surfaces were swabbed. Six surfaces, namely, the floor, wall, table, light, anesthesia workstation, and door handle, were swabbed. Samples were transported immediately to the institution's microbiology laboratory. RESULTS: During OT commencement, 247 swabs from nine OTs yielded 19 (7.29%) positives for bacterial growth. These microorganisms were primarily non-pathogenic, including aerobic spore-forming bacilli and Micrococcus, with an average bioload of 9.5 colony-forming units (CFU)/m(3) of air. During OT monitoring, swab positivity was 10.79% (23/213). The General Surgery OT and Obstetrics and Gynecology OT showed the highest bacterial growth (5/23). Surface sampling revealed prevalent methicillin-resistant coagulase-negative staphylococci (MRCoNS) (9/23), followed by methicillin-sensitive Staphylococcus aureus (MSSA) (4/23) and methicillin-sensitive coagulase-negative staphylococci (MSCoNS) and aerobic spore-forming bacilli (ASB) (3/10). The General Surgery, Obstetrics and Gynecology, and ENT OTs displayed elevated air bioloads of 53, 49, and 47 CFU/m(3), respectively. CONCLUSION: In newly constructed non-operational OTs, non-pathogenic organisms prevailed. However, as the OTs became functional, pathogenic organisms became more prevalent. Sampling emphasized contamination in areas with high patient loads, such as General Surgery, Obstetrics and Gynecology, and ENT OTs. Notably, OT tables and OT walls exhibited higher pathogenic microorganism presence. By combining both initial commencement and ongoing monitoring, the institution has effectively managed the microbial environment within its OTs.