Sufentanil does not enhance the efficacy of ropivacaine in combined lumbar plexus and sciatic block: A controlled, randomised clinical trial

SummaryTo date, data on the efficacy of the combination of opioids and local anesthetics in peripheral nerve block are not conclusive yet. In this study, the onset time, duration as well as quality of lumbar plexus and sciatic nerve blockade were evaluated using sufentanil and ropivacaine combination compared with plain ropivacaine. Forty patients scheduled for lower extremity surgery under combined lumbar plexus and sciatic nerve block were randomly allocated into two groups. Fifty millilitres of 0.375% ropivacaine with 0.5 μg/ml sufentanil (trial group) and 0.375% plain ropivacaine (control group) were administered when the location of lumbar plexus and sciatic nerve were confirmed by a nerve stimulator. Onset and duration of sensory and motor block were investigated. Opioid-related side effects were recorded. Quality of anesthesia in terms of success rate of block and patients’ satisfaction were reviewed after surgery. The addition of sufentanil to ropivacaine did not facilitate the onset of the block, nor the duration of analgesia. For lumbar plexus block, the mean onset time of sensory block was 13.9 ± 7.4 min (trial group) versus 12.4 ± 5.9 min (control group), respectively, 11.3 ± 6.5 min versus10.5 ± 4.2 min, respectively, for motor block. For sciatic nerve block, the onset time of sensory block was 14.6 ± 8.6 min versus 14.2 ± 7.0 min, respectively, 15.4 ± 7.3 min versus 13.6 ± 9.5 min, respectively, for motor block. The mean duration of sensory block is 14.3 ± 4.5 h (trial group) versus 15.2 ± 4.6 h (control group), respectively; the mean duration of motor block 17.3 ± 6.1 h versus 16.7 ± 5.3 h, respectively. Opioid-related side effects were similar between groups, as well as the success rate of the block and patients’ satisfaction. We concluded that, during combined lumbar plexus and sciatic nerve block, adding sufentanil 0.5 μg/ml to 0.375% ropivacaine solution did not provide clinically relevant advantages in terms of onset time, duration and quality of anesthesia for patients undergoing elective lower extremity surgery.