[Contamination of the operating room with anesthetic gases and vapors. Analytical methods]

An approach for the measurement of the contamination of the operating room air is presented. The measurements were performed in three operating rooms used for general surgery, partly in model experiments and partly while anesthesia was in progress. During anesthesia, the measurements were taken when oxygen 3 l/min containing ethrane 1.0--1.5% was passed into a semi-closed circle and the exhaled gas vented directly to the environmental air with no scavenging system in use. The daily exposure of operating room personnel was determined by adsorption of ethrane on glass tubes containing activated charcoal. The ethrane was subsequently desorbed in toluol and quantified by gas chromatography. The concentration of contaminant was found to be significantly greater in the anesthesiologist's position than in the areas of surgeon and circulating nurse. Some pitfalls in sampling, standardization, and analysis are indicated. Attention is drawn to the numerous factors influencing the extent of contamination.