Canadian Journal of Anesthesia, Vol 33, 550-555, Copyright © 1986 by Canadian Anesthesiologists' Society

Epidural Meperidine Analgesia After Cardiac Surgery

¹ Surgical Intensive Care Unit, The Montreal General Hospital and the Departments of Anaesthesia & Surgery, McGill University Montreal, Quebec

Address correspondence to: Dr. R.J.S. Robinson, The Department of Anaesthesia, Montreal General Hospital, 1650 Cedar Avenue, Montreal, Quebec, H3G 1A4.

Epidural meperidine (1 mg·kg^-1) was administered for relief of sternal pain to ten patients, at a mean of 24.8 hours after infusion of high dose fentanyl for cardiac surgery.

Lung function, cough, pain score, somnolence, respiratory rate, PaCO₂, pulse and blood pressure were studied before and for six hours after analgesic administration. Following epidural meperidine, four of ten patients were pain-free, and three had only minimal pain. Duration of analgesia was 8.8 ± 4.9 hours. Cough score was significantly improved for five hours. Postoperatively vital capacity was approximately 40 per cent, and FEV₁ was approximately 55 per cent of the preoperative value. There was no significant change in FEV₁ or vital capacity, following analgesia with epidural meperidine.

The somnolence score increased in seven patients. In the first two hours after epidural meperidine, three patients exhibited a fall in their respiratory rate, one had a PaCO₂ greater than 45, and two of these patients had marked hypotension. These side effects are easily treated without mechanical or pharmacological support, and do not preclude the use of epidural meperidine after a high dose fentanyl anaesthetic.

Key Words: ANAESTHETIC TECHNIQUES: epidural, epidural narcotics • ANALGESICS: meperidine • PULMONARY FUNCTION: postoperative