[The effect of epidural injection with morphine on the post-thoracotomy respiratory function]

Patients undergoing thoracotomy experience severe post-operative pain and marked respiratory impairment, which causes pulmonary atelectasis and pneumonia. The effects of epidural injection on postoperative pain and respiratory function were examined in this study. The group undergoing epidural injection of 3 mg morphine (at the end of operation, 09oo and 21oo for the next 3 days) included 37 patients, while the control group involved 16. The number of required analgesics on the operating day and next three days were compared between the two groups. And postoperative vital capacity (VC), forced expiratory volume in the first second (FEV1), maximum mean flow (MMF) were compared with preoperative value. Patients receiving epidural morphine required significantly less analgesics throughout the postoperative periods (p less than 0.01). The morphine injected group had significantly better value in VC and FEV1 in the first two postoperative day (p less than 0.01), while significance were seen only in the first postoperative day in MMF (p less than 0.01). It seems that epidural morphine is highly effective in alleviating pain and improving respiratory function in post-thoracotomy patients. These effects help the expectoration of sputum especially in senile patients. As the side-effects of epidural morphine, urinary retention, nausea, vomiting and itching were seen in few patients. No serious side effect such as hypotension or ventilatory depression were seen.