Intraoperative ketorolac dose of 15mg versus the standard 30mg on early postoperative pain after spine surgery: A randomized, blinded, non-inferiority trial.

STUDY OBJECTIVE

The primary aim of this study is to show the non-inferiority of 15mg intraoperative dose of ketorolac as compared to the standard 30mg ketorolac by looking at the visual analog scale pain (VAS) scores 4h after an adult spine surgery.

DESIGN

The study design is a prospective randomized non-inferiority clinical trial looking at non-inferiority of intraoperative 15mg ketorolac from the standard 30mg dose.

SETTING

Quaternary care center.

PATIENTS

50 adult (18-65years of age) undergoing lumbar decompression spine surgery.

INTERVENTIONS

Group A received a single intraoperative dose of 15mg ketorolac at the end of surgery and group B received single intraoperative dose of 30mg ketorolac.

MEASUREMENTS

The primary outcome was the visual analog scale (VAS) pain scores 4h after an adult spine surgery. Secondary measures were morphine usage in the first 8 and 24h postoperatively, numeric rating scores (NRS) up to 24h, sedation, nausea, vomiting, respiratory depression, pruritus and bleeding complications.

MAIN RESULTS

Intention to treat analysis showed a mean increase in 4h VAS pain score of 7.9mm (95% CI: -4.5mm to 20.4mm) in patients administered 15mg ketorolac. This difference was neither statistically (P=0.207) nor clinically significant (<18mm on VAS scale). A similar increase in the 15mg group was noted through a per protocol analysis, 6.9mm (95% CI: -6.6mm to 20.5mm, P=0.307) greater in the 15mg group. Non-inferiority of 15mg was not confirmed. No significant difference was found in secondary endpoints.

CONCLUSIONS

Ketorolac 30mg intravenous was not superior to 15mg intravenous for post-operative pain management after spine surgery. However, 15mg failed to meet the pre-specified criteria for non-inferiority to the 30mg dose.