Cooling for acute ischemic brain damage (COOL AID) - A feasibility trial of endovascular cooling

Objective: To report results of a randomized pilot clinical feasibility trial of endovascular cooling in patients with ischemic stroke. Methods: Forty patients with ischemic stroke presenting within 12 hours of symptom onset were enrolled in the study. An endovascular cooling device was inserted into the inferior vena cava of those randomized to hypothermia. A core body temperature of 33 degreesC was targeted for 24 hours. All patients underwent clinical assessment and MRI initially, at days 3 to 5 and days 30 to 37. Results: Eighteen patients were randomized to hypothermia and 22 to receive standard medical management. Thirteen patients reached target temperature in a mean of 77 +/- 44 minutes. Most tolerated hypothermia well. Clinical outcomes were similar in both groups. Mean diffusion-weighted imaging (DWI) lesion growth in the hypothermia group ( n = 12) was 90.0 +/- 83.5% compared with 108.4 +/- 142.4% in the control group ( n = 11) (NS). Mean DWI lesion growth in patients who cooled well ( n = 8) was 72.9 +/- 95.2% (NS). Conclusions: Induced moderate hypothermia is feasible using an endovascular cooling device in most patients with acute ischemic stroke. Further studies are needed to determine if hypothermia improves outcome.