The mechanical aspects of anesthetic pollution control.

Reduction of anesthetic contamination in the operating room requires removal of excess circuit gases (scavenging), elimination of anesthetic equipment leakage, and avoidance of anesthetic technics which allow unopposed spill of gas into the operating room. Scavenging and disposal of excess anesthetic gases can present hazards to the patient; means to protect the breathing circuit from elevated positive and negative pressures should be of prime consideration in selecting a scavenging system. Leakage from anesthic equipment occurs in the high-pressure (central and tank N2O sources to the machine flowmeters) and the low-pressure portions (from the machine flow-meters to the patient) of the system and can be of sufficient magnitude to virtually negate effective scavenging. These leakage points can be readily detected and corrected using periodic simple test procedures.