Bacterial and Fungal Isolates From Operating Theatres at Kenyatta National Hospital

Abstract

BACKGROUND: Hospital operating theatre equipment and the environment air may harbour bacteria, viruses, yeasts, and fungal spores. Susceptible patients undergoing surgery in such an environment may develop post-operative infections. Environmental surveillance to detect varying microbial levels for possible eradication is therefore necessary. OBJECTIVES: To identify major fungal and bacterial isolates and to determine their patterns in different specialized operating theatres at the Kenyatta National Hospital (KNH). METHODS: This was a cross-sectional study done at KNH. A total of 1372 samples from 12 operating theatres were collected between December 2017 and February 2018. Surface samples were taken with sterile wet swabs from different equipment and exposure of agar plates in the air. Settle plate method and colony forming unit per cubic metre was used to detect fungal and bacterial levels in different specialities. Student t-test was used to examine statistical significance for the varying bacterial and fungal isolate in different specialities against established normal levels in operating theatres. RESULTS: There were 10 different bacterial genera isolated in swab samples notably: Coagulase Negative Staphylococci 86(44.5%) and Staphylococci aureus 44(22.8%), which are the major theatre equipment contaminants. Air contaminant in agar plates was dominated by Staphylococcus epidermidis 185(73%) and coliforms (21%). Additionally, 5 genera and 10 species of fungi were also isolated. Aspergillus spp 81(71.64%) predominated fungal isolates with Aspergillus fumigatus alone constituted 36 (31.9%) of the fungal isolates. There was no statistical significance in theatre isolates between different specialties. The mean settle rate was < 0.5 and <15cfu/m3 which was within international standards. CONCLUSION: This study showed that the KNH theatres had significantly low bacterial and fungal contamination rate on equipment swabbed and agar plate exposure as cfu/m3 and settle rate were within international acceptable limits. RECOMMENDATION: Effective cleaning, fumigation, dumb-dusting, regular change of disinfectants and contamination checks are necessary for operating theatres. The Presence of undesired microbial isolates (Staphylococci spp, Aspergillus spp) necessitates effective cleaning and disinfection of equipment and floors in operating theatres at all times.