Effect of postoperative analgesia on surgical outcome.

Despite improvements in perioperative care, major surgical operations are still followed by sequelae such as pain, organ dysfunction and prolonged convalescence. It has been assumed that suf®cient pain relief will improve the surgical outcome with reduced morbidity, need for hospitalization and convalescence, and there is a common consensus that optimal (dynamic) pain relief is a prerequisite for early postoperative recovery. However, in recent years it has been realized that several other factors in perioperative management are important in the control of postoperative recovery and rehabilitation, and that these factors must be considered and revised in order to achieve the advantageous effects of pain relief on outcome. Among the most commonly used pain-relieving techniques [patient-controlled analgesia (PCA) with opioids, non-steroidal anti-in ̄ammatory drugs (NSAIDs) and epidural analgesic techniques], there is evidence that the epidural local anaesthetic or local anaesthetic±opioid techniques are the most effective on providing dynamic pain relief after major surgical procedures. 79 This paper reviews data from randomized controlled trials on the effects of these analgesic techniques on postoperative morbidity and hospital stay (with emphasises on epidural analgesia) in order to derive useful conclusions on the relationship between optimal pain relief and postoperative outcome. The effect of peripheral nerve blocks on postoperative morbidity will not be dealt with in this review.