Remifentanil versus Fentanyl for Analgesia in Mechanically Ventilated Patients: A Multicenter, Prospective, Randomized, Double-Blind, Parallel-Group Clinical Trial.

Fentanyl is approved for use in many countries as an analgesic for patients requiring mechanical ventilation. However, it redistributes and accumulates easily in the plasma because of its long half-life. Remifentanil is a short context-sensitive half-life analgesic with a lower risk of redistribution and accumulation.We conducted a multicenter, randomized, double-blind, non-inferiority trial. Critically ill patients requiring mechanical ventilation were randomly allocated to receive an infusion of either remifentanil or fentanyl for up to 72 h. The primary outcome was the analgesic success rate. A 95% confidence interval lower boundary greater than -8% for the difference between the groups was considered to indicate non-inferiority between the drugs.A total of 137 patients received remifentanil (69) or fentanyl (68). Remifentanil's non-inferiority to fentanyl concerning its analgesic success rate was established (difference, 5.97%; 95% confidence interval: -3.99% to 16.35%). Mechanical ventilation duration, extubation duration, successful extubation, intensive care unit discharge, intensive care unit length of stay, and adverse events did not differ significantly between the two groups.Remifentanil was non-inferior to fentanyl regarding the analgesic success rate in critically ill patients requiring mechanical ventilation.