Feasibility and Safety of Intravascular Temperature Management for Severe Heat Stroke: A Prospective Multicenter Pilot Study

Objectives: Heat stroke is a life-threatening condition with high mortality and morbidity. Although several cooling methods have been reported, the feasibility and safety of treating heat stroke using intravascular temperature management are unclear. This study evaluated the efficacies of conventional treatment with or without intravascular temperature management for severe heat stroke. Design: Prospective multicenter study. Setting: Critical care and emergency medical centers at 10 tertiary hospitals. Patients: Patients with severe heat stroke hospitalized during two summers. Interventions: Conventional cooling with or without intravascular temperature management. Measurements and Main Results: Cooling efficacy, Sequential Organ Failure Assessment score, occurrence rate of serious adverse events, and prognosis based on the modified Rankin Scale and Cerebral Performance Category. Patient outcomes were compared between five centers that were prospectively assigned to perform conventional cooling (control group: eight patients) and five centers that were assigned to perform conventional cooling plus intravascular temperature management (intravascular temperature management group: 13 patients), based on equipment availability. Despite their higher initial temperatures, all patients in the intravascular temperature management group reached the target temperature of 37°C within 24 hours, although only 50% of the patients in the control group reached 37°C ( p < 0.01). The intravascular temperature management group also had a significant decrease in the Sequential Organ Failure Assessment score during the first 24 hours after admission (4.0 vs 1.5; p = 0.04). Furthermore, the intravascular temperature management group experienced fewer serious adverse events during their hospitalization, compared with the control group. The percentages of favorable outcomes at discharge and 30 days after admission were not statistically significant. Conclusions: The combination of intravascular temperature management and conventional cooling was safe and feasible for treating severe heat stroke. The results indicate that better temperature management may help prevent organ failure. A large randomized controlled trial is needed to validate our findings.