Analgestic efficacy of intermittent boluses for adductor canal block after total knee arthroplasty / 临床麻醉学杂志

ABSTRACT

Objective To compare two different regimens of ultrasound-guided Continuous ad-ductor canal block (CACB)for postoperative analgesia and early ambulation after total knee arthro-plasty (TKA).Methods Sixty-seven patients scheduled for unilateral TKA undergoing spinal anes-thesia,13 males and 54 females,aged 18-85 years,BMI 18-30 kg/m2,ASA physical status Ⅰ-Ⅲ, were randomly divided into the continuous infusion group A (n=34)and the intermittent boluses group B (n=33).After the operations,ultrasound-guided CACB were administered and 20 ml of 0.2% ropivacaine was given as the loading dose.From then on,patients in both groups used electronic analgesic pumps containing 240 ml of 0.2% ropivacaine for postoperative analgesia.5 ml/h of 0.2% ropivacaine was continuously infused for 48 hours in the group A.5 ml of 0.2% ropivacaine was automated injected every 60 minutes in the group B.All infusion pumps were setted at a bolus dose of 5 ml,with a lock time of 30 minutes.The total consumptions of analgestic pum solution and dezoine, quadriceps muscle strength, active range of knee flexion, ambulation distance and occurrences of adverse reactions such as nausea and vomiting,dizziness,drowsiness,extravasating and errhysis were recorded at different time points postoperatively.Results The total consumptions of analgestic pum solution at 12,24 h postoperatively of group B were significantly reduced than that of group A (P<0.05).The 48 h total dezoine consumption of group B was significantly reduced than group A (P<0.05).Active range of knee flexion at 24,48 h and ambulation distance at 48,72 h of group B were significantly higher than group A (P<0.05).There was no statistical difference in quadriceps muscle strength between group A and group B.The incidence of nausea and vomiting in group A was significantly higher than that in group B,and there were no statistical difference in other adverse reactions between group A and group B.Conclusion Compared with the continuous infusion group,the intermittent bolus group for CACB after TKA can provide better analgesic effect and de-crease opioid use postoperatively,with little effect on motor nerve,promoting early ambulation.