Endovascular cooling with heat exchange catheters: A new method to induce and maintain hypothermia

Objective: To test the convenience of a new cooling technique with intravenous heat exchange catheters. Design: Retrospective chart review. Setting: University hospital neurointensive care unit. Patients: Twenty patients with severe subarachnoid hemorrhage Hunt and Hess Grade 3-5 treated with mild hypothermia. Interventions: Cooling to reach target body core temperature (33 degreesC-34 degreesC) was induced as quickly as possible in all patients. In the first ten patients (group one) moderate hypothermia was induced and maintained using cooling blankets. In group two, an 8.5F heat exchange catheter was placed central venous and temperature-adjusted normal saline circulated in a closed-loop system entailing two balloons. Measurements and results: A total of 2,007 values of body core temperature (BCT) were registered every hour. Foley temperature catheters were used for monitoring BCT in the bladder. The time to reach the target BCT and the stability of temperature during hypothermia were compared between the two groups. No specific complications associated with the new cooling device were observed. Time to reach the target temperature in group two was significantly shorter than in group one (190+/-110 and 370+/-220 min) (P=0.023). In group one significantly more temperature values were out of the target range (127 of 792 values; 16.0%) than in group two (62 of 1,215 values; 5.1%) (P<0.0001). Conclusions: The new endovascular cooling technique seems to be superior for rapid induction of hypothermia and maintaining a more stable temperature than the cooling techniques using blankets and ice bags.