Clinical trial of an air-circulating cooling blanket for fever control in critically ill neurologic patients

Objective: To evaluate the efficacy of an air-circulating cooling blanket for reducing body temperature in febrile neuro-ICU patients treated with acetaminophen. Methods: Two-hundred twenty consecutively admitted neuro-ICU patients whose tympanic membrane temperature reached or exceeded 101 degreesF (38.3 degreesC) were randomly assigned to receive acetaminophen (650 mg every 4 hours) alone (n = 107) or acetaminophen plus air blanket therapy (n = 113). After 24 hours of treatment, the authors compared the proportion of subjects who attained treatment success (T less than or equal to 99 degreesF) or treatment failure (T greater than or equal to 101 degreesF for 2 consecutive hours) using the chi (2) test and the time to reach these endpoints using Kaplan-Meier survival analysis. Main Results: Air blanket therapy resulted in a small increase in the proportion of subjects with treatment success (44% versus 36%, chi (2) p = 0.19, log rank p = 0.10) and a similar small reduction in the proportion of patients with treatment failure (42% versus 53%, chi (2) p = 0.11, log-rank p = 0.21), compared with treatment with acetaminophen alone. Approximately one third of patients in both groups remained febrile after randomization and "failed" after the first 2 hours of treatment. Twelve percent of patients assigned to air blanket therapy refused or were unable to tolerate treatment, compared with 2% of patients treated with acetaminophen alone (p = 0.005). Conclusions: Treatment with an air-circulating cooling blanket did not effectively reduce body temperature in febrile neuro-ICU patients treated with acetaminophen. More effective interventions are needed to maintain normothermia in patients at risk for fever-related brain damage.