Validation of a Prediction Model for Intraoperative Hypothermia in Patients Receiving General Anesthesia

Table 2

Descriptive statistics of perioperative temperature and patient warming (N = 227).

Variable	Value
Baseline core temperature prior to anesthesia (°C)	36.56 ± 0.44
Type of thermometry at baseline
Axillary thermometer	210 (92.5%)
Other^a	17 (7.5%)
Perioperative lowest temperature (°C)	35.99 ± 0.52
Intraoperative passive warming^b	227 (100.0%)
Intraoperative active warming^c (N = 217)	10 (4.6%)
Volume of intraoperative intravenous fluid (mL)	1500 (1100–2200)
Intravenous fluid warming (N = 219)
Unwarmed	144 (65.8%)
Prewarmed	18 (8.2%)
Continuously warmed	57 (26.0%)
Volume of irrigation fluid (mL, N = 205)	500 (50–1000)
Irrigation fluid warming (N = 151)
Unwarmed	109 (72.2%)
Prewarmed	42 (27.8%)
Blood transfusion (mL); median (range)	0 (0–1200)
Warming of blood transfusion (N = 13)
Prewarmed	5 (38.5%)
Continuous warming	8 (61.5%)
Ambient temperature (°C)
Preoperative holding area (N = 200)	25.5 ± 2.7
Operating room (N = 217)	22.2 ± 0.9
Postanesthesia care unit (N = 196)	24.1 ± 1.9

Data are shown as n/N (% of nonmissing data), mean ± SD, or median (IQR), unless otherwise specified. IQR, interquartile range; SD, standard deviation. a Others include an infrared tympanic thermometer and nasopharyngeal probe. b Passive warming includes cotton blankets, surgical drapes, and others. c Intraoperative active warming includes forced-air warming, electric blankets, and others.