Objective: Since 2001, at our institution, a portable and percutaneous cardiopulmonary bypass system has been used for rewarming of patients with accidental deep hypothermia. Before 2001, a conventional internal rewarming technique was used. The aim of this research is to examine the efficacy of portable and percutaneous cardiopulmonary bypass for rewarming of patients with accidental severe hypothermia and compare it with that of conventional rewarming methods.
Design: Historical study.
Setting: The exclusive emergency medical center and trauma center level 1 in Western Kanagawa, Japan.
Patients: From April 1992 to March 2009, 70 patients with accidental deep hypothermia (core temperature <28°C) were transferred to our hospital. Two patients presented with intracranial hemorrhage on initial head computed tomography scans. These two patients were excluded because each required an emergency operation. Therefore, 68 patients were included in this study. We compared patients' clinical characteristics and outcomes. The parameters included the following: sex, age, vital signs on arrival to our hospital (Glasgow coma Scale scores, systolic blood pressure, heart rate, respiratory rate, core temperature), electrocardiogram on arrival to our hospital, rewarming speed, time of rewarming until 34°C was reached, ventricular fibrillation occurrence rate during rewarming, cause of cold environmental exposure, Glasgow Outcome Scale scores, and mortality. In addition, we divided the conventional and portable and percutaneous cardiopulmonary bypass rewarming groups into two categories depending on whether cardiopulmonary arrest occurred on arrival to our hospital. We also compared the survival rate and average Glasgow Outcome Scale scores for each group.
Interventions: None.
Measurements and main results: Patients' clinical backgrounds did not differ significantly between the conventional and portable and percutaneous cardiopulmonary bypass rewarming groups. Glasgow Outcome Scale scores and survival rates of the portable and percutaneous cardiopulmonary bypass rewarming group patients, irrespective of whether cardiopulmonary arrest was experienced on arrival to our hospital, were significantly higher than those of the conventional rewarming group.
Conclusions: Portable and percutaneous cardiopulmonary bypass rewarming can improve the mortality rates and Glasgow Outcome Scale scores of accidental deep hypothermia patients.