Effect of Ultrasound-guided Nerve Block With 0.75% Ropivacaine at the Mid-forearm on the Prevalence of Moderate to Severe Pain After Hand Surgery

Purpose

This study tested the hypothesis that ultrasound-guided mid-forearm nerve block with 0.75% ropivacaine reduces the prevalence of moderate to severe pain after wrist and hand surgery, and provides prolonged postoperative analgesia with minimal motor blockade.

Methods

Thirty patients undergoing elective wrist and hand surgery were randomly assigned to 1 of 2 groups: group R (n = 15) and group NS (n = 15). We combined an ultrasound-guided supraclavicular brachial plexus block with mid-forearm median, radial, and ulnar nerve block in all patients. The supraclavicular brachial plexus was blocked with 20 mL of 1.5% lidocaine, and the mid-forearm nerves were blocked with 15 mL of either 0.75% ropivacaine (group R) or normal saline (5 mL each nerve) (group NS). A blinded observer provided a numeric rating pain score at 1, 2, 6, 12, 24, and 48 hours after surgery. The durations of sensory and motor blockade, patient satisfaction, morphine requirement for postoperative pain rescue, and adverse events were recorded.

Findings

The prevalence of moderate to severe pain in group R was significantly lower than that in group NS (33% vs 86%; P = 0.008). The highest mean (SD) numeric rating pain score (worst pain) in group R was lower than that in group NS (2.7 1.9] vs 5.6 2.9]; P = 0.004), and the median (Q1, Q3) amount of morphine required for postoperative pain rescue in group R was lower than that in group NS (0 0, 6] vs 8 6, 10]; P = 0.001]. Additionally, there were no differences in the durations of motor blockade between the 2 groups.

Implications

Based on the findings from this study, ultrasound-guided mid-forearm nerve block with 0.75% ropivacaine significantly reduces the prevalence of moderate to severe pain after wrist and hand surgery, provides long-term postoperative analgesia, and facilitates the return of motor function in the upper limb. Chinese Clinical Trial Registry identifier: ChiCTR-IOR-15007278 (October 2015).