[Usefulness of a new nasal cannula with an end-tidal carbon dioxide measuring port].
BACKGROUND
During light sedation under local anesthesia, usually only percutaneous arterial oxygen saturation (SpO2) has been monitored for respiration. Measuring end-tidal carbon dioxide tension (EtCO2) has been difficult in such cases because of many air leaks from mask or cannula. We investigated the usefulness of a new nasal cannula with which EtCO2 can be monitored simultaneously with oxygen delivery.


METHODS
Forty patients receiving epidural and spinal anesthesia were sedated with intravenous midazolam followed by propofol infusion. Oxygen 2l.min-1 was administered by a new nasal cannula of which one side of the face piece provides oxygen and the other side of it is an EtCO2 measuring port. SpO2 and EtCO2 were measured.


RESULTS
The lowest SpO2 was 96 +/- 2%. The EtCO2 wave and value were demonstrated all the time during surgery in 24 patients, while in the other 16 patients sometimes it failed to indicate wave and value of EtCO2 when patients were snoring or moved their face.


CONCLUSIONS
A new cannula with EtCO2 port is useful to oxygenate and measure EtCO2 simultaneously except when patients snore or move.
Surgical Center, Institute of Medical Science, University of Tokyo, Tokyo 108-8639.
Tomoki
T
Nishiyama
Kazuo
K
Hanaoka
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000765:Anesthesia, Conduction; D002245:Carbon Dioxide / Q000032:analysis*; D002404:Catheterization; D016292:Procedural Sedation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation*; D009296:Nasal Cavity; D010100:Oxygen / Q000008:administration & dosage; D013990:Tidal Volume
D002245:Carbon Dioxide; D010100:Oxygen