Do oxygen-enriched atmospheres exist beneath surgical drapes and contribute to fire hazard potential in the operating room?
The purposes of this study were to (1) describe the microenvironment in terms of oxygen concentration beneath the drapes of healthy subjects who were simulating patients undergoing minor surgical procedures with supplemental oxygen and to (2) evaluate the efficacy of using a scavenger system beneath the drapes. A convenience sample of 12 healthy volunteer subjects was studied in an ambulatory surgery center operating room, which was ventilated with 25 air exchanges per hour. The study was carried out in 2 parts. Each subject was supine, and oxygen was applied by a standard nondivided nasal cannula. The subjects were draped as routinely done for ophthalmic procedures. Oxygen concentrations were measured by using an Ohmeda Rascal II gas analyzer beneath the drapes and at the hypothetical surgical site with oxygen flow rates of 0, 1, 2, 3, and 4 L/min, allowing 5 minutes to elapse after a change in flow rate was made. Following a 10-minute break, the subjects were redraped, and the proced