A prospective, multicenter pilot study to evaluate the feasibility and safety of using the CoolGard System and Icy catheter following cardiac arrest.

BACKGROUND: Cardiac arrest causes devastating neurological morbidity and mortality. Mild/moderate hypothermia is neuroprotective after global cerebral ischemia. More rapid controlled attainment of the target temperature may increase efficacy.
METHODS: We assessed the safety and feasibility of endovascular cooling in a single arm study of comatose patients who had been successfully resuscitated after cardiac arrest. Core temperature was reduced to a target of 33 degrees C for 24 h using a closed loop endovascular system placed in the inferior vena cava, followed by controlled rewarming. Primary outcomes were speed and accuracy of cooling, survival and GOS after 30 days.
RESULTS: Thirteen patients were enrolled, six male, age 60 +/- 19 years. Time from cardiac arrest to return of spontaneous circulation was 14.3 min (range 5-32.5). It took 3h and 39 min (median 210 min, IQ 80-315) to reach 33 degrees C; cooling averaged 0.8 +/- 0.3 degrees C/h (range 0.22-1.12 degrees C/h). Temperature was tightly maintained for all patients averaging 32.7 +/- 0.5 degrees C. Rewarming lasted 18.3 +/- 5.9 h. Five patients (38%) had 30-day Glasgow Outcome Scores of 1-2. Four patients died, none related to the hypothermia procedure. No unanticipated or procedure-related adverse events occurred.
CONCLUSION: In comatose survivors of cardiac arrest, hypothermia via endovascular methods is safe and feasible, and target temperatures can be achieved and controlled rapidly and precisely. More studies are needed to assess the efficacy of rapid endovascular hypothermia after cardiac arrest.