Remifentanil and Hyperalgesia: Gradual Withdrawal Versus Immediate Discontinuation

Modern anesthesia has made a lot of progress, however, postoperative pain remains one of the major problems associated with patient discomfort, prolonged hospital stay and increased health care costs. Remifentanil is an ultra-short-acting phenylpiperidine opioid analgesic with high lipid solubility and a rapid onset of effect. Recently, opioid use has also been associated with postoperative opioid-induced hyperalgesia or acute opioid tolerance. An immediate discontinuation of remifentanil has been associated to increased postoperative pain levels. We would like to investigate whether a gradual post-operative withdrawal of remifentanil is indeed associated with less immediate pain compared to after an abrupt withdrawal in surgical patients undergoing minor surgery.