Acute pain management in patients receiving opioids for chronic and cancer pain

The number of patients receiving large doses of opioids presenting for surgery is increasing as opioids gain a wider utilization in the treatment of chronic pain. These patients need to be identified before surgery because they may be tolerant to the effects of opioids prescribed according to standard postoperative analgesic regimens designed for the opioid naive patient. Additionally, these patients may have developed a physical dependence on opioids that needs to be satisfied postoperatively. An insufficient dose may result in unrelieved pain and/or an opioid withdrawal reaction. In general, opioid tolerance, physical dependence and withdrawal may be a significant problem in patients who have been on high doses of weak opioids (e.g. codeine >120 mg or tramadol >400 mg daily) or strong opioids (e.g. morphine or oxycodone) for >2 weeks preoperatively. © The Board of Management and Trustees of the British Journal of Anaesthesia [2005] All rights reserved.