ANESTHESIA FOR CORONARY-ARTERY BYPASS-SURGERY SUPPLEMENTED WITH SUBARACHNOID BUPIVACAINE AND MORPHINE - A REPORT OF 18 CASES

We report our experience with general anaesthesia (GA) supplemented with subarachnoid bupivacaine and morphine for coronary artery bypass surgery (CABG) in 18 patients. Fifteen patients were male, and mean age was 62 yr. Anaesthesia (GA) was induced with alfentanil 97 +/- 22 mu g.kg(-1) and midazolam 0.04 +/- 0.02 mg.kg(-1) supplemented with a muscle relaxant, and maintained with isoflurane (0.25-0.5%) in oxygen throughout surgery. Spinal anaesthesia (SA) was then performed at a lumber level using hyperbaric bupivacaine (23-30 mg) and/or lidocaine (150 mg) with morphine (0.5-1 mg) Pooled data showed the following haemodynamic results (P < 0.05). Induction of GA produced a decrease in mean arterial pressure (MAP). Addition of SA produced a decrease in heart rate. Heart rate and MAP did not change with sternotomy. Phenylephrine support of arterial blood pressure was used at some time during operation in 17 patients. Supplementation of GA was minimal. Patients received 2.7 +/- 0.7 coronary grafts. Operating room time wars 3.9 +/- 0.6 hr. Postoperative analgesic requirements were minimal, and in half of the patients tracheal extubation occurred on the day of surgery. Complications included one myocardial infarction, one resternotomy, a metabolic encephalopathy in a dialysis-dependent patient, and one case of herpes labialis. No patient recalled intraoperative events. Combined GA with SA may be an effective technique for CABG surgery. Further study of the cardiovascular, neurological and metabolic effects of the technique is required.