[Usefulness of monitoring forehead deep-tissue temperature as an index of core temperature in adult patients undergoing laparotomies under general anesthesia--investigation in operating rooms with air-movement control system using vertical flow].
BACKGROUND
Acute changes in air temperature in the vicinity of the patents' forehead may impair clinical usefulness of the forehead deep-tissue thermometry. We thus investigated usefulness of monitoring the forehead deep-tissue temperature as an index of core temperature in 12 adult patients undergoing laparotomies in operating rooms with air-movement control system using vertical flow.


METHODS
Nasopharyngeal, forehead deep-tissue, palm deep-tissue, and fingertip skin-surface temperatures were recorded during surgery every 5 minutes in operating rooms where room temperature was thermostatically controlled at approximately 25 degrees C. The patients were not actively warmed with forced-air warmers, but covered with cotton blankets where possible. The deep-tissue and fingertip skin-surface temperatures were compared with the nasopharyngeal temperature using regression and Bland and Altman's analyses.


RESULTS
The four temperatures continued decreasing during surgery, and the nasopharyngeal temperature decreased to below 36 degrees C 2 hours after induction of anesthesia. Only the forehead deep-tissue temperature satisfactorily correlated with the nasopharyngeal temperature (r = 0.76, n = 300, P < 0.0001). The difference between nasopharyngeal and forehead temperatures was +0.26 degree C, and its standard deviation was 0.34 degree C.


CONCLUSIONS
The forehead deep-tissue temperature has sufficient accuracy and precision for clinical use in operating rooms with air-movement control system using vertical flow. However, the core temperature appears to be slightly underestimated with the forehead deep-tissue thermometry.
Department of Anesthesiology and Critical Care Medicine, Faculty of Medicine, Kyushu University, Fukuoka 812-8582.
Takashi
T
Akata
Yukiko
Y
Machida
Jun
J
Yoshino
Tomohiro
T
Hirai
Michiko
M
Sato
Jun
J
Takamatsu
Shosuke
S
Takahashi
D000328:Adult; D000389:Air Conditioning / Q000379:methods*; D000392:Air Movements; D000768:Anesthesia, General; D001831:Body Temperature; D005260:Female; D005546:Forehead / Q000502:physiology*; D006801:Humans; D007813:Laparotomy; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D009873:Operating Rooms