An evaluation of the microbial retention performance of three ventilator-circuit filters.
OBJECTIVE
to determine and compare the microbial retention efficiency of 3 types of heat and moisture exchange (HME) filters.


METHODS
randomised prospective study.


METHODS
Intensive Care Unit at the Middlesex Hospital and the microbiology laboratory of the Department of Academic Microbiology, University College London Medical School.


RESULTS
An aerosol challenge to each filter using a suspension containing. S. marcescens and the bacteriophage MS2. In total 45 filters of 3 types were tested, 15 previously unused and 30 that had been used in ventilator circuits of 30 patients. The 3 types of filter generally had microbial retention efficiencies of > 99.99% for both S. marcescens and the bacteriophage MS2.


CONCLUSIONS
The 3 types of HME filter were effective microbial filters and comparable in their microbial retention.
Holton
J
J
Department of Microbiology, University College London Medical School, UK.
Webb
A R
AR
D000336:Aerosols; D004866:Equipment Contamination; D004867:Equipment Design; D005069:Evaluation Studies as Topic; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D006813:Humidity; D007362:Intensive Care Units; D017909:Levivirus; D010316:Particle Size; D011446:Prospective Studies; D012121:Respiration, Artificial; D012706:Serratia marcescens
D000336:Aerosols