Resistance of disposable drapes to bacterial penetration.

PURPOSE To test the bacterial penetrability of disposable non-woven drapes used specifically for total hip arthroplasty. METHODS 12 round agar plates were inoculated with 107 colony-forming units/ml of coagulase-negative staphylococci (CNS) and incubated in air at 37 degrees Celsius for 18 hours to obtain a semi-confluent growth of organisms. Six brands of disposable drapes were tested; each was assigned to 2 plates. Each disposable drape was placed between a round agar plate and an inverted square agar plate filled with blood agar. After 30 and 90 minutes, the square agar plates were removed and incubated for 48 hours and inspected for growth of CNS. RESULTS Bacterial penetration was time dependant. Certain brands of drapes were more impenetrable than others; none was impenetrable at all time points, but most remained so or allowed passage of fewer than 100 colony-forming units at 90 minutes. CONCLUSION It is recommended that drapes be rigorously tested with regard to their resistance to bacterial penetration.