[Accidental decrease in the air flow during air/oxygen sevoflurane anesthesia].

We describe our experience of an accidental decrease in the air flow during air/oxygen sevoflurane anesthesia. According to the malfunction of an air compressor system, dehydration of the compressed air was inadequate, and the wet air was delivered to the anesthesia machine. The moisture was formed at a flow control valve to cause a gradual decrease in the air flow. The low-pressure alarm did not work at that time, because the pressure of the air supply was normal. There are two types of medical air, one is produced from the ambient air by air compressor system and another is the synthetic air which is a mixture of oxygen and nitrogen. Although the synthetic air is always dry and clean, the former contains dust, bacteria, and moisture. There is a possibility that all of these particles cannot be excluded before use. Accordingly, we must check the air compressor system routinely when a source of the compressed air is used.