Intrathecal morphine for coronary artery bypass graft procedure and early extubation revisited

Objective:To determine the dose of intrathecal (IT) morphine (along with th e intraoperative baseline anesthetic) that provides significant analgesia y et does not delay extubation in the immediate postoperative period in patie nts undergoing cardiac surgery and early extubation, Design: Prospective, randomized, double-blinded, placebo-controlled clinica l study. S etting: Single university hospital. Participants: Forty patients undergoing elective coronary artery bypass gra ft procedure and early extubation, Interventions: Twenty patients received 10 mu g/kg of IT morphine, and 20 p atients received IT placebo. Perioperative anesthetic management was standa rdized and included postoperative patient-controlled morphine analgesia. Main Results: Of the patients tracheally extubated during the immediate pos toperative period, mean time to extubation was similar in patients who rece ived IT morphine (6.8 +/- 2.8 h) or IT placebo (6.5 +/- 3.2 h), Four patien ts who received IT morphine had extubation substantially delayed because of prolonged ventilatory depression, There was no difference between groups i n postoperative patient-controlled morphine analgesia use, Conclusion:Even when used in conjunction with an intraoperative baseline an esthetic that allows early extubation, IT morphine (10 mu g/kg) was unable to provide substantial postoperative analgesia. The risks of using IT morph ine in patients undergoing cardiac surgery and early extubation may outweig h the potential benefits. Copyright (C) 1999 by W.B. Saunders Company.