Objective: Accidental deep hypothermia (ADH)--a condition in which the core body temperature is less than 28 degrees C--is a medical emergency; the mortality rates for ADH remain high. The efficacy of cardiopulmonary bypass (CPB) rewarming has been proved in ADH patients with cardiopulmonary arrest; however, its efficacy in the ADH patients without cardiopulmonary arrest remains controversial. In our study, we evaluated the efficacy of portable percutaneous cardiopulmonary bypass (PPCPB) for rewarming and providing cardiovascular support in the hemodynamically unstable ADH patients without cardiopulmonary arrest.
Methods: Between April 2001 and March 2006, we performed a retrospective study at Tokai University, Kanagawa, Japan. We studied 24 ADH patients without cardiopulmonary arrest (male:female ratio, 15:9; mean age, 68.5 +/- 12.9 years) with hemodynamic instability who had not developed intracranial hemorrhage. We evaluated the efficacy of PPCPB rewarming by estimating the mean time of initiation of PPCPB after admission, rewarming speed, the success rate of rewarming, the rate of weaning from PPCPB, the incidence of ventricular fibrillation (Vf) during rewarming, complications associated with PPCPB, mortality rate, and the Glasgow Outcome Scale (GOS) scores of the patients who survived.
Results: The mean time of initiation of PPCPB after admission was 41.9 +/- 7.9 minutes. The rewarming speed was 4.0 +/- 1.5 degrees C/h. A 100% success rate was achieved after the rewarming procedure, whereas the rate of weaning from PPCPB was 91.7%. Vf during rewarming developed in one case; however, electrical defibrillation was possible. No direct complications of PPCPB were observed. The mortality rate was 12.5% (3/24). The GOS scores of the patients who survived were as follows: 5 points, 17 cases; 4 points, 3 cases; and 3 points, 1 case.
Conclusion: PPCPB rewarming is a clinically efficacious procedure for rewarming and providing cardiovascular support in hemodynamically unstable ADH patients without cardiopulmonary arrest who have not developed intracranial hemorrhage.