THE EFFECT OF BISPECTRAL INDEX MONITORING ON PROPOFOL CONSUMPTION IN PATIENTS UNDERGOING CORONARY ARTERY BYPASS GRAFT

This study was aimed to investigate whether BIS monitoring can improve recovery from propofol anesthesia and decrease the propofol requirement or no. In a randomized, prospective design, 20 patients received propofol, at target dose 100 µg/kg/min and intraoperative anesthetic management was blinded to BIS values, whereas in 20 patients propofol was titrated to maintain a BIS value of 40-60. Mean arterial pressure and bispectral index were recorded at various time intervals. Monitoring was equal in all cases. Mild hypothermic CPB was applied in all patients. Statistical analysis used 2-tailed t test, and chi2 analysis. Patient demographic data, operation performed, hypothermia application, times of anesthesia, duration of operation, and CPB were similar in the both groups. None of the patients reported awareness during a standardized interview. The total dose of propofol was lower in the study group but there were no statistical differences (1.95 mg/Kg/hr in study vs. 2.59 mg/kg/hr in control group and p>0.05) and there was no significant difference in ex-tubation time among two groups. The BIS is useful for monitoring the depth of anesthesia but the use of BIS cannot be valuable in guiding the administration of propofol intraoperatively for coronary artery bypass graft requiring cardiopulmonary bypass. Further investigations with other type of surgeries and shorter time operations are recommended.