[The evaluation of tracheal temperature to monitor core temperature in various operations]

Tracheal temperature was evaluated to monitor core temperature during cardiac, upper abdominal and lower abdominal operations. The tracheal temperature was measured by a thermistor attached to the intra-cuff of the tracheal tube. In cardiac surgery, there was a good correlation between tracheal temperature and forehead deep temperature (r = 0.93) before and after cardiopulmonary bypass, and also between tracheal temperature and the temperature of blood from the cardiopulmonary bypass (r = 1.00) during cardiopulmonary bypass. These results indicate that tracheal temperature accurately reflects carotid artery temperature. In upper abdominal operations, the tracheal temperature showed good correlations with forehead core, esophageal, bladder and rectal temperatures (r = 0.81-0.90). On the other hand, bladder and rectal temperatures were different from forehead deep (r = 0.43, 0.55) and tracheal temperatures in lower abdominal operations. These results suggest that the tracheal temperature is valuable to monitor core temperature.