An Assessment of the Benefit of Surgical Face Masks in Preventing Aerosol Droplet Spread during a Simulated Spinal Anaesthetic-a Blinded in vitro Study
Abhijit Biswas *
Clinical Fellow, Regional Anaesthesia, Toronto Western Hospital, Toronto, Canada.
S. Ó. Riain
Department of Anaesthesia and Intensive Care, Mid Western Regional Hospital, Limerick, Ireland.
J. Saunders
Statistical Consulting Unit, University of Limerick, Ireland.
D. Barron
Department of Microbiology, Mid Western Regional Hospital, Limerick, Ireland.
N. O. Connell
Department of Microbiology, Mid Western Regional Hospital, Limerick, Ireland.
*Author to whom correspondence should be addressed.
Abstract
Aims: The purpose of this study was to assess the benefit of wearing a surgical face mask in reducing aerosol contamination of agar plates in a simulated spinal anaesthetic. The contamination of plates with virulent organisms, association of growth with recent upper respiratory tract infection and food intake were also studied.
Methods: A poster containing written text was fixed to a wall, with a standard agar plate suspended at its midpoint. Each volunteer (n=30) then read the text from the wall chart to simulate verbal interaction with a patient during a spinal anaesthetic, initially wearing a surgical mask and then once again without a mask.
Results: This study revealed an increased risk (p =0.006) of bacterial growth on agar plates when not wearing a surgical face mask. Results also suggest that eating prior to surgical procedures may increase the risk of contamination of the surgical field in the absence of a barrier mask.
Keywords: Facemasks, oral commensals, meningitis.