Nalbuphine Versus Ketorolac as an Adjuvant to Local Wound Infiltration Anesthesia in Open Colorectal Surgery: A Prospective Randomized Controlled Study.

INTRODUCTION: Adding adjuvants to local wound infiltration (LWI) provides long analgesic duration with fewer adverse effects. We aimed to compare the clinical effects of nalbuphine and ketorolac as an adjuvant to LWI in patients undergoing open colorectal cancer surgery. METHOD: A total of 126 ASA I-III patients aged ≥ 18 years who were scheduled for open colorectal cancer surgery were included. Patients were randomly assigned to receive LWI using 10 mL 0.75% ropivacaine, with 20 mL normal saline (group R), 10 mg nalbuphine in 1 mL (group RN), or 25 mg ketorolac in 0.8 mL (group RK). Analgesia duration was the primary outcome. The total 48-h postoperative morphine-equivalent consumption and additional rescue analgesia rates were recorded as key secondary outcomes. RESULTS: Among 126 patients randomized, 124 completed the trial. The duration until the first press of the analgesia pump was significantly shorter in group R (median: 320.0 min) compared with group RN (median: 829.5 min) and group RK (median: 820.0 min) (P < 0.001). The median difference in morphine consumption was 113.0 mg for group R vs. group RN (P < 0.001), and 115.5 mg for group R vs. group RK (P < 0.001). The proportion of patients using additional morphine within the first day after surgery in group R showed a higher relative risk (RR) compared with group RN (RR, 3.89; P = 0.001) and group RK (RR, 3.17; P = 0.001). There were no apparent differences between the RN and RK groups in any outcomes, whether in adjusted or unadjusted analysis. CONCLUSIONS: Among patients undergoing open colorectal cancer surgery, both nalbuphine and ketorolac infiltration achieved equally prolonged duration of analgesia and reduced morphine consumption compared with ropivacaine alone after surgery, suggesting that the equivalent analgesic dose of nalbuphine and ketorolac as local anesthetic adjuvants in LWI could have a similar analgesic effect. TRIAL REGISTRATION: ChiCTR1800019209.