Systemic hypothermia in treatment of brain injury.
An extensive literature suggests that there are minimal complications of systemic hypothermia in humans at and above 30 degrees C for periods of several days. Intracranial hemorrhage has been found to complicate profound hypothermia (10-15 degrees C), and ventricular arrhythmias occur at temperatures below 30 degrees C. Our initial clinical studies were with 21 patients undergoing elective craniotomy cooled to 30-32 degrees C for 1-8 h (mean 4 h). Hypothermia was induced by surface cooling with water blankets. No complications were found. Among 11 patients with severe brain injury, cooling to levels below 32 degrees C was associated with ventricular arrhythmias in 1 patient and atrioventricular block in 1 patient. Asymptomatic hypokalemia was found routinely and treated with potassium replacement. No intracranial hemorrhage or other complications were found. With surface cooling, intravascular temperature dropped at 1.6 degrees C/h. Based on the safety of surface cooling to a core temperature of 32 degrees C for 48 h, we are conducting a randomized study of this level of hypothermia in patients with severe brain injury, cooled within 6 h of injury.
Clifton
G L
GL
Department of Surgery, University of Texas Health Science Center, Medical School, Houston.
Allen
S
S
Berry
J
J
Koch
S M
SM
D001831:Body Temperature; D001927:Brain Diseases / Q000601:surgery / Q000628:therapy*; D001930:Brain Injuries / Q000628:therapy*; D001932:Brain Neoplasms / Q000601:surgery / Q000628:therapy; D003399:Craniotomy; D005240:Feasibility Studies; D006801:Humans; D007036:Hypothermia, Induced