Efficacy of the Steri-Shield filtered exhaust helmet in limiting bacterial counts in the operating room during total joint arthroplasty

Filtered exhaust helmets (space suits) have been reported as efficacious in decreasing wound infections following joint arthroplasty procedures; however, strict experimental control of the many variables related to the incidence of clinical infection has been lacking in these studies, making support of such conclusions difficult. Any potential benefit of filtered exhaust helmets in the control of infection rates can be logically assigned to the reduction of airborne bacterial counts within the operating room. A study was done using the Steri-Shield helmet (Bio-Medical Devices, Irvine, CA) to define its efficacy in limiting airborne bacterial contaminates during total joint arthroplasty. Forty-eight paired prosthetic hip and knee cases were evaluated using a block experimentation design. One case of each pair was done with all surgical and scrub personnel cloaked in Steri-Shield filtered exhaust helmets and the other with the same personnel in conventional paper hoods and masks. Air samples were obtained with an Anderson two-stage viable particle sampler (Anderson Samplers, Atlanta, GA) placed immediately adjacent to the wound. Quantitative microbial cultures were obtained. The filtered exhaust helmet evaluated in this study provided no increased protection against bacterial contamination in the area of the surgical field than conventional paper hoods and masks.