Mortality impact of hypothermia after cavitary explorations in trauma.

BACKGROUND: Admission hypothermia (core temperature
METHODS: After institutional review board (IRB) approval, all critically ill trauma patients undergoing cavitary surgery (laparotomy or thoracotomy) at a level 1 trauma center from 01/1998 to 07/2006 were identified from the trauma registry. Immediate postoperative core temperature (Tc) was used to classify patients as hypothermic (Tc35 degrees C). The profoundly hypothermic subgroup of patients with a Tc<33 degrees C was also analyzed.

RESULTS: During the study period, 2,489 patients required cavitary surgery, 1,252 of whom (50%) were admitted to the intensive care unit (ICU). On arrival in the ICU 15% of the patients had a Tcor=55 years old (12% versus 7%; p=0.04); in addition, they were hypotensive on admission (25% versus 13%; p<0.001), had a lower admission Glasgow Coma Score (GCS; 11+/-5 versus 14+/-3; p<0.001), a higher Injury Severity Score (ISS; 29+/-15 versus 22+/-12; p<0.001), higher head and chest Abbreviated Injury Scale (AIS), and greater intraoperative blood loss (2.6+/-2.4 l versus 1.7+/-1.8 l; p<0.001). When compared to patients who were normothermic at the end of their operation, hypothermic patients had a significantly higher mortality (35% versus 8%; p<0.001). With decreasing Tc, there was a stepwise increase in mortality. Compared to patients with a Tc>35 degrees C, the relative risk of death for patients with a Tc between 35 degrees C and 33 degrees C was 4.0, and that for patients with a Tc
CONCLUSIONS: Postoperative hypothermia is common in critically injured patients requiring cavitary surgery and is an independent predictor of mortality. The impact of measures to maintain or restore normothermia in the operating room warrants further investigation.