Bacterial contamination of stethoscopes of anaesthetists in the department of anaesthesiology

A research report submitted to the Faculty of Health Sciences, University of Witwatersrand, in fulfilment of the requirements for the degree of Masters of Medicine. Johannesburg, 2016Background South Africa has a huge burden of infectious diseases as many patients are immunocompromised and are at an increased risk for infection. An almost unnoticed piece of equipment possibly harbouring pathogens is the stethoscope. Alcohol swabs are readily available and have been shown to effectively reduce the growth of micro-organisms on stethoscopes. Methods Data was collected from 26 anaesthetists and their stethoscopes in the Department of Anaesthesiology at two academic hospitals in Johannesburg. Two samples were taken from each stethoscope. Group A was assigned to the stethoscope samples that were taken prior to disinfecting the stethoscope with a 70% isopropyl alcohol swab and Group B was assigned to the stethoscope samples that were taken after disinfecting of the stethoscope. Anaesthetists were then asked about their frequency of cleaning the stethoscopes. Results In Group A 19 (73%) stethoscopes grew micro-organisms. Micro-organisms were identified on three stethoscopes in Group A. Two stethoscopes grew coagulase-negative staphylococcus (CNS) and one stethoscope grew Staphylococcus aureus. In Group B, 5 (19.2%) cultured micro-organisms. The only micro-organism identified in this group was CNS. The results showed that most anaesthetists even if infrequently disinfected their stethoscopes. Conclusion This study demonstrated the contamination of stethoscope diaphragms in the Department of Anaesthesiology and the effectiveness of disinfecting the stethoscope with a 70% isopropyl alcohol swab. Most of the anaesthetists reported disinfecting their stethoscopes.MT201