DOES CARDIOPULMONARY BYPASS TEMPERATURE CORRELATE WITH POSTOPERATIVE CENTRAL-NERVOUS-SYSTEM DYSFUNCTION

A National Institutes of Health-funded trial of perfusate temperature and neurological function was begun in the Baystate Medical Center in February 1994. It randomizes patients having coronary revascularizatio n to three temperatures-warm (37 degrees C), tepid (32 degrees C), and cold (20 degrees C)-for systemic perfusate and blood cardioplegia tem perature at 37 degrees C warm, 32 degrees C tepid, and 6 degrees C to 10 degrees C cold. The goal is to have a quantitated neurological exam ination performed prior to operation, prior to discharge at day 3 or 4 , and at a 1-month follow-up interval. The initial 51 patients complet ing a 1-month follow-up broke down to 14 cold, 22 tepid, and 15 warm. The neurological examination quantitated their performance on the Math ew Scale, an ordinal measure from 1 to 100, with 100 being normal. The re was a significant (p < 0.05) decrease across the entire study from preoperative to postoperative that was no longer present at late follo w-up. Although the lowest mean scores (94.8) occurred in the warm grou p, they were not statistically different from the other groups', and t here was no discernible influence of temperature on neurological funct ion. Additional patients will be entered to validate a difference if s uch exists.