The passage of bacteria through surgical drapes is a potential cause of wound infection. Previous studies have shown that liquids and human albumin penetrate certain types of drapes¹². We studied the passage of bacteria through seven different types of surgical drape and an operating tray. We also studied the effect of different wetting agents on the passage of bacteria through wet reusable woven drapes. Bacteria were grown on an overfilled whole horse blood agar plate. The plate was covered with the drape to be tested and a second agar plate was inverted and placed on the drape. After 30 minutes the second agar plate was removed, incubated and inspected for bacterial growth. The experiment was repeated removing the second plate at 60 minutes and then again at 90 minutes. The entire experiment was repeated for each drape and then for each wetting agent.

Bacteria easily penetrated all the woven reusable fabrics within 30 minutes. The disposable non-woven drapes proved to be impermeable up to 90 minutes, as did the operating tray.

Chlorhexidine and Povidone-Iodine were demonstrated to slow, but not stop the passage of bacteria through reusable woven drapes. Normal saline and human blood accelerated the passage of bacteria through reusable woven drapes. We recommend the use of non-woven disposable drapes or woven drapes with an impermeable operating tray, in all surgical cases.