Remifentanil Decreases Pain, Analgesic Use Following Knee Arthroscopy

For patients undergoing knee arthroscopy, the administration of intra-articular remifentanil immediately following the procedure may decrease postoperative pain and analgesic use, according to the results of a study published in the Journal of Orthopaedic Science.

Patients (N=60) undergoing arthroscopic knee surgery at the Mashhad University of Medical Sciences in Iran between 2019 and 2021 were recruited for this single-center, randomized, double-blind, placebo-controlled trial. Patients were randomly assigned to receive remifentanil 200 μg dissolved in 25 mL saline (n=30) or 25 mL saline (n=30) placebo administered into the intra-articular space at the end of surgery. Postoperative pain at rest was evaluated using the visual analog scale (VAS) up to 24 hours following the procedure.

The intervention and control cohorts consisted of 80.0% and 83.3% men, respectively, and the mean ages of participants in each cohort were 31.9 (standard deviation [SD], 6.6) and 33.53 (SD, 7.44) years.

Recipients of remifentanil reported lower VAS pain scores at 1 (mean, 2.23 vs 8.66; P =.0001), 3 (mean, 2.56 vs 8.0; P =.0001), 6 (mean, 2.03 vs 7.36; P =.0001), 12 (mean, 0.86 vs 5.33; P =.0001), 18 (mean, 0.56 vs 3.60; P =.0001), and 24 (mean, 0.10 vs 2.53; P =.0001) hours following surgery compared with participants in the control group, respectively.

In addition, only 36.7% of the individuals receiving remifentanil requested analgesics compared with 100% of individuals in the placebo cohort (P =.0001). Recipients of remifentanil had a longer time to request for first analgesic (median, 3 vs 1 h; P =.0001), they received fewer analgesics (median, 0 vs 4; P =.0001), and they required a lower dose of meperidine (median, 0 vs 100 mg; P =.0001) compared with participants in the control group, respectively.

No side effects of treatment were observed.

This study may have been limited by the lack of data on the preoperative pain levels of study participants.

These findings indicate that remifentanil administered in the intra-articular space immediately following knee arthroscopy was associated with significant reductions in pain scores and analgesic use within the first 24 hours after surgery. The study authors conclude, “[w]e suggest remifentanil as an effective alternative to other drugs for relieving pain after knee arthroscopic surgeries, but for other types of intra-articular surgeries, it should be investigated carefully.”