Opioid-free anesthesia significantly improves early postoperative pain scores and reduces nausea and vomiting following laparoscopic surgery compared to traditional opioid-based techniques, according to a double-blinded randomized controlled trial published on September 28, 2026, in the Cureus Journal of Medical Science (Vol. 18, No. 9, e117045). Led by Sneha A. Johnson and colleagues at Shri Sathya Sai Medical College and Research Institute in Chengalpattu, India, the study tracked 62 adult patients undergoing elective laparoscopic appendectomies or cholecystectomies.
Trial Design and Patient Demographics
The prospective trial randomized 62 participants into two equal groups of 31 between November 2024 and January 2026. Researchers evaluated patients aged 18 to 60 classified as American Society of Anesthesiologists physical status I through III. The opioid-free anesthesia group received intravenous dexmedetomidine at 1 µg/kg, ketamine at 0.2 mg/kg, and lignocaine at 2 mg/kg prior to induction, followed by a dexmedetomidine infusion of 0.5 µg/kg/hour. The comparator group received intravenous fentanyl at 2 µg/kg before induction alongside an intraoperative infusion of 0.5 µg/kg/hour. Baseline characteristics including age, body mass index, and surgery duration showed no statistically significant differences between the cohorts.
Postoperative Pain and Analgesia Outcomes
Postoperative pain was measured using a 10-centimeter Visual Analog Scale at 2, 6, 12, 24, and 48 hours. Patients receiving opioid-free anesthesia recorded significantly lower Visual Analog Scale scores at six hours (3.2 ± 0.8 versus 4.6 ± 1.2; Holm-adjusted p < 0.001), as well as sustained improvements at 12 and 24 hours. Scores at two and 48 hours remained comparable between groups. Within the first six postoperative hours, rescue analgesia was required by one participant in the opioid-free group and six participants in the opioid-based group, though this difference did not reach statistical significance on Fisher’s exact test (p = 0.104). Among patients who required rescue medication, the reported mean time to first rescue analgesia reached 8.7 ± 1.9 hours in the opioid-free cohort compared to 7.0 ± 1.7 hours in the comparator cohort.
Complications and Hemodynamic Findings
Postoperative nausea and vomiting occurred less frequently in patients managed without opioids. Specifically, zero participants in the opioid-free group experienced nausea and vomiting at six hours, compared to six participants in the opioid-based group (p = 0.024). Overall complications, defined as at least one recorded adverse event, affected one participant in the opioid-free group versus eight participants in the opioid-based group (p = 0.026). Perioperative heart rate and systolic blood pressure remained comparable across time points, while diastolic blood pressure and mean arterial pressure showed modest elevations in the opioid-free group at six hours postoperatively.
Common Questions Regarding Anesthesia Protocols
What drugs were used in the opioid-free protocol?
Patients in the opioid-free group received intravenous dexmedetomidine, ketamine, and lignocaine before induction, followed by a continuous dexmedetomidine infusion.
How was postoperative pain measured in the study?
Researchers used a 10-centimeter Visual Analog Scale ranging from 0 representing no pain to 10 representing the worst imaginable pain at 2, 6, 12, 24, and 48 hours.
Were there differences in surgical times between the study groups?
No, the mean duration of surgery was 83.1 ± 15.3 minutes in the opioid-free group and 84.2 ± 9.8 minutes in the opioid-based group.
What were the main adverse events evaluated?
The trial tracked postoperative nausea and vomiting, shivering, pruritus, bradycardia, and overall complication rates.
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