THE EFFECT OF A PORTABLE HEPA-FILTERED BODY EXHAUST SYSTEM ON AIRBORNE MICROBIAL-CONTAMINATION IN A CONVENTIONAL OPERATING-ROOM

OBJECTIVE: To study the effect of a portable HEPA-filtered air exhaust system (Stackhouse Freedom Surgical Helmet System) on airborne microb ial contamination in a modern conventional operating room. DESIGN AND SETTING: Microbial air sampling was done with a two-stage Anderson sam pler at the wound site during 46 total joint replacements. All operati ons were performed by the same surgeon in the same operating room at a large community hospital. RESULTS: In 18 cases done without air exhau st hoods, the number of bacterial and fungal colony-forming units (CFU ) ranged from 0.6 to 11.7 (mean, 3.6). Air sampling during 28 operatio ns with the operating team in air exhaust hoods revealed a mean of 3.6 CFU (range, 0 to 11.4). Bacterial CFU averaged 3.4 without hoods and 3.2 with exhaust hoods. Coagulase-negative staphylococci were the most common isolates (48% of isolates with hood, 55% without hood). No inf ections occurred. CONCLUSION: We conclude that these air exhaust hoods did not lower airborne microbial contamination detectable with this a ir sampling method, as compared to standard head cover and mask, in a modern conventional operating room (Infect Control Hosp Epidemiol 1996 ;17:419-422).