EFFECTS OF INTRATHECAL OPIOID ON EXTUBATION TIME, ANALGESIA, AND INTENSIVE-CARE UNIT STAY FOLLOWING CORONARY-ARTERY BYPASS-GRAFTING

Study Objective: To determine if intrathecal opioid decreases time to extubation after coronary artery bypass surgery without compromising p ostoperative analgesia. Design: Prospective randomized trial. Setting: Veterans Affairs Hospital. Patients: 21 ASA physical status III and I V men scheduled for elective coronary bypass surgery, who had not rece ived medications that would impair anticoagulation at the time of surg ery. Interventions: Patients were randomized to receive 10 mu g/kg mor phine and 25 mu g fentanyl intrathecally preoperatively (n = 12) or no intrathecal opioid (n = 9). The latter group-received 25 to 50 mu g/k g fentanyl and 0.05 to 0.1 mg/kg midazolam intraoperative tively, wher eas the intrathecal opioid group received intravenous (IV) fentanyl an d midazolam only as needed. Both groups were administered IV morphine and midazolam postoperatively as needed by intensive care unit (ICU) p ersonnel who were blinded to the treatment group. Measurements and Mai n Results: For the first 24 hours postoperatively, pain levels (0 = no ne, to 10 = most severe) and sedation levels (1 = none, to 5 = unconsc ious) were measured hourly. The time to extubation and discharge from the ICU was recognized. ECG evidence of myocardial ischemia was noted. Pain scores were low for both groups (1.5), but the intrathecal opioi d subjects exhibited less sedation than the high-dose fentanyl subject s [means +/- standard deviation (SD) of 2.3 +/- 0.4 vs. 2.8 +/- 0.5, p = 0.03]. Extubation time was 12 hours shorter in the intrathecal opio id group (2.9 +/- 5.3 vs. 14.7 +/- 6.8, p = 0.001). The five subjects with a one day ICU stay were all in the intrathecal opioid group (P = 0.04). The incidence of myocardial ischemia did not differ between the two groups. Conclusions: Intrathecal opioid can facilitate early extu bation and discharge from the ICU without compromising analgesia or in creasing myocardial ischemia. (C) 1997 by Elsevier Science Inc.