Epidural morphine analgesia compared with intravenous morphine for oral cancer surgery with pectoralis major myocutaneous flap reconstruction

Abstract

Oral cancer surgery with reconstruction is a complex operative procedure with morbidities such as respiratory complications and post-operative pain. These morbidities may be reduced with appropriate operative and post-operative pain management. Epidural analgesia provides better pain control than intravenous opioids after major thoraco-abdominal surgical procedures. We planned to undertake a prospective study to compare the efficacy and side-effects of epidural morphine analgesia vs. intravenous morphine in patients undergoing oral cancer surgery with pectoralis major myocutaneous flap reconstruction. Sixty patients undergoing a major surgical procedure for oral cancer with pectoralis major myocutaneous flap reconstruction were prospectively randomized to receive either epidural morphine or intravenous morphine in the post-operative period. The intensity of pain was assessed daily using a 100-mm visual analogue scale. The post-operative side-effects, time to ambulation, time to tolerate first nasogastric feed, total length of hospital stay and global satisfaction score were recorded. The epidural morphine group had statistically significant lower pain scores at the three evaluation times through the post-operative 48 h (P < 0.05). However, the mean visual analogue scores were always below 35 in the intravenous morphine group. Patients in the epidural morphine group ambulated and accepted nasogastric feed significantly earlier than those in the intravenous morphine group. The incidence of nausea/vomiting or pruritus, the length of hospital stay and the global satisfaction score were not statistically different between the groups. This study illustrates that epidural morphine offers better pain control than intravenous morphine after oral cancer surgery with pectoralis major myocutaneous flap reconstruction. Nevertheless, both methods appear to provide very good pain relief, and perhaps the extra risks inherent to epidural catheter insertion are not outweighed by the benefits in this type of surgery.