Remifentanil and worse patient-reported outcomes regarding postoperative pain management after thyroidectomy.

Background: Intraoperative remifentanil has been associated with postoperative hyperalgesia, higher visual analogic pain scores, and increased postoperative morphine consumption. However, this has not been investigated from patient's perspective by using a patient-reported outcomes (PROs) approach with a validated questionnaire.

Methods: We joined the largest prospective observational study on postoperative pain, PAIN OUT Project (NCT02083835), and collected data for 2 years. We studied the effects of remifentanil (R+) vs nonremifentanil (R-) anesthesia on PROs regarding their pain management after elective thyroidectomy. We selected 5 primary PROs (worst pain experienced, time spent in severe pain, relief received by treatment, satisfaction about pain management, wish for more pain treatment) and five secondary PROs (drowsiness, itching, nausea, dizziness, waking up due to pain) from the validated International Pain Outcomes questionnaire.

Results: The analysis included 317 patients, 208 in the R+ group (65.6%) and 109 in the R- group (34.4%), the latter receiving fentanyl as intraoperative opioid. Although the R+ group received more frequently intraoperative nonopioids (202/208, 97.1% vs 86/109, 78.9%; P < .0001) and opioids (184/208, 88.5% vs 38/109, 34.9%; P < .001), it reported higher worst pain (5.1±2.1 vs 4.3±2.1, P < .005), lower satisfaction (7.4±2.0 vs 8.1±2.1, P < .001), and worse results in 4 secondary PROs. A sensitivity analysis performed matching 67 couples of patients yielded similar results in primary PROs.

Conclusions: Our study suggests that remifentanil-based anesthesia is associated with worse pain-related PROs in patients undergoing thyroidectomy despite more frequent intraoperative analgesic administration. This study adds further evidence to the growing literature about opioid- and remifentanil-induced hyperalgesia.