A Comparative Study Between Ultrasound vs Nerve Stimulator for Femoral (3 in 1) and Sciatic Nerve Blocks for Major Knee Surgeries

Abstract

Major Knee surgeries are one of the most frequently performed surgical procedures among different age groups. Associated diseases in those patients represent a challenge for choosing the type of anesthesia and analgesia. In the past decade, there has been an increased interest in performing lower extremity PNBs because of the potential complications associated with central neuraxial blockade, i.e. increased risk of epidural hematoma with new anti-thromboembolic prophylaxis regimens, and transient neurologic symptoms associated with spinal anesthesia. Additionally, evidence that improved rehabilitation outcome may be associated with continuous lower extremity PNBs has stimulated even more interest. The advances in regional techniques for blocks of the lower limb have been driven primarily by the need to produce effective and prolonged analgesia in the postoperative period. Increasingly, modern practice demands a shorter hospital stay, improved patient expectations and early mobilization. The aim of the study was to compare US guided femoral (3 in 1) and sciatic nerve blocks with NS regarding safety, efficacy, and rate of success & failure. The study was conducted on 80 randomly chosen patients in Ain Shams University department of orthopedics after approval of the medical ethical committee. They were allocated in two groups of 40 patients each: Group A (NS): Lower limb femoral (3 in 1) and sciatic nerve blocks using NS alone. Group B (US): US guided lower limb femoral (3 in 1) and sciatic nerve blocks. Bupivacaine 0.25% was used for injection. 40 ml of local anesthetic was injected in femoral (3 in 1) nerve block and 20 ml in sciatic nerve block in all groups, care was taken so that not exceed the toxic bupivacaine dose [3 mg/kg]. All patients were adequately monitored all through the procedure and till the end of the operation. Comparison between both groups were done regarding time to perform the blocks, number of attempts, hemodynamics, time to sensory block, time to motor block, degree of the motor block, duration of the block, rate of failure of the block, duration of the block, pain scoring, and occurrence of complications. Results of our study showed that US group was superior to the NS group regarding number of attempts, time required for sensory and motor blocks, rate of failure was higher in the NS group but the results was unsignificant.