The effects of intermittent bolus paravertebral block on analgesia and recovery in open hepatectomy: a randomized, double-blinded, controlled study

BACKGROUND: We aimed to investigate the effects of intermittent bolus paravertebral block on analgesia and recovery in open hepatectomy. METHODS: Eighty 18–70 years old, American Society of Anesthesiologists level I-III patients scheduled for hepatectomy with a J-shaped subcostal incision were enrolled and randomized to receive either intermittent bolus paravertebral ropivacaine (0.5% loading, 0.2% infusion) or 0.9% saline infusion at 1:1 ratio (25 ml loading before surgery, 0.125 ml/kg/h bolus for postoperative 48 h). The primary outcome was set as postoperative 48 h cumulative intravenous morphine consumption recorded by a patient-controlled analgesic pump. RESULTS: Thirty-eight patients in each group completed the study. The cumulative morphine consumptions were lower in the paravertebral block than control group at postoperative 24 (difference -10.5 mg, 95%CI -16 mg to -6 mg, P < 0.001) and 48 (difference -12 mg, 95%CI -19.5 mg to -5 mg, P = 0.001) hours. The pain numerical rating scales at rest were lower in the paravertebral block than control group at postoperative 4 h (difference -2, 95%CI -3 to -1, P < 0.001). The active pain numerical rating scales were lower in the paravertebral block than control group at postoperative 12 h (difference -1, 95%CI -2 to 0, P = 0.005). Three months postoperatively, the paravertebral block group had lower rates of hypoesthesia (OR 0.28, 95%CI 0.11 to 0.75, P = 0.009) and numbness (OR 0.26, 95%CI 0.07 to 0.88, P = 0.024) than the control group. CONCLUSIONS: Intermittent bolus paravertebral block provided an opioid-sparing effect and enhanced recovery both in hospital and after discharge in patients undergoing hepatectomy. TRIAL REGISTRATION: clinicaltrials.gov (NCT04304274), date: 11/03/2020.