Air Contamination of Procedure Rooms in a Gastroenterological Unit with Enteric Bacteria

Abstract

Air Contamination of Procedure Rooms in a Gastroenterological Unit with Enteric Bacteria Stephan M. Wildi, Alexander Imhof, Stephan R. Vavricka, Markus Spiess, Christian Ruef, Michael Fried Background: Air contamination of procedure rooms with enteric bacteria is of concern. As a consequence, high power air conditioning systems were installed in many units. To date, there is no data quantifying the amount of air contamination in procedure rooms. Aim: To demonstrate that there is a significant air contamination with bacteria in procedure rooms of a GI unit depending on the type of procedures performed. Methods: Two hundred liters of air were sampled continuously for 2 minutes in three different procedure rooms (colonoscopy, upper endoscopy, abdominal ultrasound). The procedure rooms were equipped with a high power air conditioning system. Airborne bacteria were collected by an impactor air-sampler (MAS-100) that exposed the aspirated air directly to standard Petri dishes (sheep blood). The samplings were performed before the first procedure started (7 am), during daytime (11 am), and late after the last procedure before cleaning (5 pm). At each Petri dish, colony forming units per m (cfu/m) were counted. Results: Measurements were performed on 5 consecutive days. The results (mean values) are displayed in the table below. There is a significant increase of bacterial air contamination during daytime (p Z 0.005). The colonoscopy room is during daytime more contaminated than the other two procedure rooms (p Z 0.05). The analysis of the colonies identified predominantly enterococci and micrococci. Conclusions: The present study indicates that the highest bacterial contamination occurs predominantly during daytime and in the colonoscopy room. The clinical significance of air contamination by enteric bacteria in procedure rooms needs to be determined.