Endovascular cooling for moderate hypothermia in patients with acute stroke - First results of a novel approach

Background and Purpose-We undertook this study to evaluate the feasibility of inducing and maintaining moderate hypothermia with the use of endovascular rather than surface cooling. Methods-Six patients with severe acute ischemic stroke were treated with moderate hypothermia. This was induced and maintained by circulating temperature-adjusted normal saline in a closed-loop system entailing 3 balloons located near the tip of a central line, which dwelled in the inferior vena cava. Results-The mean SD initial temperature of the patients was 37 +/- 1 degreesC (range, 35.5 degreesC to 38.4 degreesC). The pace of cooling was 1.4 +/- 0.6 degreesC/h, and target temperature was reached after 3 +/- 1 hours (range, 2 to 4.5 hours). During hypothermia, the maximal temperature observed was 33.4 degreesC, and the minimal temperature was 32.2 degreesC. Temperature deviations >0.2 degreesC or >0.3 degreesC were observed during 21% or 10% of the hours under hypothermia, respectively. Singultus was the only device-related complication encountered. Pulmonary infection, arterial hypotension, bradycardia, arrhythmia, and thrombocytopenia were the most common side effects. Conclusions-Induction and maintenance of hypothermia with an intravenous cooling device are feasible. The safety of this approach remains to be evaluated.