Vaporizers convert liquid anesthetics into measured amount of vapor that are added to the fresh gas mixture to produce known concentrations of anesthetics. As with anesthesia machines, mordern precision vaporizers require regular checks with respect to technical safety by experts. Some private hospitals in Korea do not have had a anesthesiologist belong exclusively to hospital. Therefore it is difficult to perform a regular checks of anesthesia machine especially vaporizers. We had a question about the accuracy of vaporizer output which used in the private hospitals.

We investigated outputs of 47 vaporizers which used in 23 private hospitals and 5 general hospitals around Kangdong Gu and Kangnam Gu in Seoul, Korea. Anesthetic agent monitor(Biochem anesthetic agent monitor 8100, Waukesha, Wisc, USA) was used and its analysis value was 0.1 vo1%. 50 vo1% O2 and 50 vol% N2O were used as a carrier gas. The flow rates of the carrier gas were 4 1/min. Dial settings were 0.5, 1, 1.5, 2, 3 vo1%.

The result was that vaporizers which had the inaccuracy ranges of concentration less than ±0.5 vo1% was 76.6% of 47 vaporizers, ±1 vo1% was 93.6%. And above ±1 vol% was 6.4% of all.

This research concludes that great care needed when the anesthesiologist strange to the vaporizers in the private hospitals operates the vaporizers.