Intraoperative Remifentanil Infusion and Postoperative Pain Outcomes After Cardiac Surgery—Results from Secondary Analysis of a Randomized, Open-Label Clinical Trial

Abstract

Report of secondary pain outcomes from a prospective, randomized, open-label clinical trial that compared remifentanil and fentanyl on perioperative hyperglycemic response in cardiac surgery. Single institution, tertiary university hospital. The study comprised 116 adult elective cardiac surgical patients. Participants were randomly assigned to receive either intermittent fentanyl boluses (F) or continuous remifentanil infusion (R) intraoperatively. Postoperative pain was evaluated with pain scores every 6 hours for 48 hours. Pain threshold to mechanical stimuli was measured around the sternotomy incision at 48 and 96 hours. The development of chronic pain was assessed using the numeric rating scale at 1, 3, 6, and 12 months after discharge. The final analysis included 106 patients. Pain scores and wound hyperalgesia were not significantly different postoperatively between the groups. The incidence of chronic pain at 3 months was comparable in both groups (61% in group F v 58% in group R; p = 0.79). Pain of more-than-mild degree was seen in 13 (32%) patients in group F and 8 (19%) in group R (p = 0.25) at 3 months. Median pain scores were not significantly different between the groups at 1, 3, 6, and 12 months after discharge from the hospital. The present study's findings suggested that intraoperative remifentanil infusion does not significantly worsen pain outcomes in patients undergoing elective cardiac surgery.