effects of a very low dose naloxone addition to intraoperative remifentanil infusion on postoperative pain in patients undergoing total hip replacement surgery: a randomized clinical trial

Background: the objective of this study was to assess the effect of adding a very low dose of naloxone to a remifentanil infusion on postoperative pain in patients undergoing hip replacement surgery in the lateral position.methods: this randomized clinical trial involved 80 patients who underwent hip replacement surgery under general anesthesia and were randomly assigned into two groups through block randomization: group 1 received remifentanil at a dose of 0.3 μg/kg/minute, while group 2 received remifentanil at a dose of 0.3 μg/kg/minute with a very low dose of naloxone administered at 0.05 μg/kg/hour following injection. postoperative pain [measured using the visual analog scale (vas)], drowsiness caused by narcotics and analgesics in recovery, and the duration of getting out of bed were all monitored and recorded in the ward.results: the median [interquartile range (iqr)] of time to administration of the first sedative drug was 0 (0, 4) hours in the control group and 4 (0, 4) hours in the intervention group. the difference between the groups was statistically significant (p < 0.0001). the frequency of pain after surgery at 0, 4, and 8 hours was significantly different between the control and intervention groups (p = 0.003, p < 0.0001, and p = 0.021, respectively).conclusion: based on the results, we recommend using a very low dose of naloxone along with remifentanil infusion in patients undergoing complete hip replacement surgery to reduce their pain and the need for painkillers.