AbstractBackground and objectives:
Intermittent boluses for neural blockade provide better post-operative analgesia when compared to continuous infusion. However, these techniques of administration have not yet been compared while performing adductor canal block (ACB). We compared intermittent vs. continuous ACB for managing post-operative pain following anterior cruciate ligament (ACL) reconstruction. The primary endpoint was total morphine consumption for 24 h post-operatively in both the groups. Secondary outcomes included evaluation of pain scores and opioid-related side effects.Methods:
After ethics board approval, subjects presenting for ACL reconstruction were randomized to receive either continuous ACB (n = 25) with 0.5% ropivacaine infusing at 2.5 ml/h or intermittent boluses (n = 25) of 15 ml of 0.5% ropivacaine every 6 h. Total morphine consumption 24 h following surgery was recorded in each group.Results:
Fifty subjects completed this study. The mean 24-h total morphine consumption in the intermittent group, [11.36 (6.82) mg], was significantly reduced compared with the continuous group, [23.40 (10.45) mg] (P < 0.001). The mean visual analogue scale (VAS) pain score at rest and on knee flexion was significantly reduced in the intermittent group at 4, 6, 8, and 12 h compared with the continuous group.Conclusion:
Intermittent ACB allowed significantly reduced consumption of morphine for 24 h in the post-operative period compared with continuous ACB when identical doses of ropivacaine were used in each group.