Continuous epidural perfusion of morphine and bupivacaine for post-thoracotomy analgesia. Comparison between thoracic and lumbar epidural analgesia]

Relief of postoperative pain and the incidence of side effects occurring after continuous epidural infusion of morphine and bupivacaine were evaluated in patients undergoing a thoracotomy. We also studied the relevance of a close proximity of the epidural catheter to the metameric segment were the pain originated. The study involves 17 patients divided into two groups. In one series (lumbar group) (LG) the catheter was located at the lumbar region and in the other series (thoracic group) (TG) the catheter was localized at the thoracic area. The study was carried out during the first 48 hours following surgery. Bupivacaine 2% and 0.2 mg/ml of morphine hydrochloride were administered at an initial rate of 1.5 ml/h. The total dose required for pain relief was greater in LG than in TG (p less than 0.05). There were no significant group differences in the hemodynamic and respiratory parameters measured in this study. Only respiratory rate was occasionally lower in LG. Three patients presented postoperative atelectasis (2 in TG and 1 in LG) and required bronchoscopy. One patient of LG complained pruritus and another one of the same group presented nausea and vomiting. The epidural perfusion was interrupted in only one patient of TG due to the presence of arterial hypotension. The association of narcotics and local anesthetics in continuous epidural perfusion was an excellent method for achieving pain relief with minimum side effects. We conclude that both thoracic and lumbar epidural routes are advisable for post-thoracotomy pain relief.