The Effects Of Continuous Adductor Canal Block Combined With Sciatic Nerve Block And Obturator Nerve Block For Pain Relief And Inflammatory Response For Patients Undergoing Total Knee Arthroplasty

Total knee arthroplasty(TKA)is the best method for treating end-stage knee osteoarthritis.However,majority of patients undergoing TKA experience severe pain postoperatively,which is associated with anxiety,uncomfortability,delayed ambulation,and impaired knee function convalescence.Reasonable pain management contributes to promoting the rapid rehabilitation of patients after surgery,which is important for better long-term functional outcome.Optimal analgesia for TKA aims to minimize pain as well as to preserve motor function.Peripheral nerve block(PNB)and local infiltration analgesia(LIA)can provide analgesia with less side effects than continuous epidural analgesia or intravenous self-controlled analgesia and become more popular in orthopaedic surgery.In recent years,with the development of neurostimulator and ultrasonography(US)a major progress has been made in regional anesthesia.The location of nerves,puncture needles and the diffusion of local anesthetics(LA)are visible with the introduction of ultrasound technology,thus improving the success rates and safety of nerve block.The knee joint is mainly controlled by the femoral nerve and its branches,the sciatic nerve and its branches,and the anterior and posterior branches of the obturator nerve.Femoral nerve block(FNB)can improve the analgesic effect after TKA,but it tends to result in motor weakness due to significant reduction of quadriceps strength and increased the risk of falls after TKA.Adductor canal block(ACB)has been shown to provide analgesic effects similar to FNB,and can significantly reduce pain and opioid consumption with sparing quadriceps strength and promoting postoperative mobilization.Though ACB provides significant analgesia for the peripatellar and intraarticular pain,it does not control posterior knee moderate to severe pain.Pain of the posterior knee capsule hinders the full extension of the knee joint and affects its rehabilitation.Recent data has shown that femoral nerve block combined with sciatic nerve block(SNB)can further reduce pain after TKA,especially in popliteal fossa.It has been reported that the analgesic method of FNB combined with SNB is the best solution for postoperative analgesia after TKA.Femoral nerve block combined with obturator nerve block(ONB)can also reduce pain and opioid consumption after TKA compared with FNB independently,and can be used as a part of multimodal analgesia after TKA.Local infiltration anesthesia(LIA)is used for pain management after TKA alone,or combined with FNB/ACB.Owing to simple implementation,no impairing quadriceps strength,LIA is widely used in surgical pain control.However,some studies have pointed out that LIA is effective in the first few hours postoperative,but the prolonged analgesia effect on the first day after surgery is poor,and there is no consensus on the formulation of LIA at present.Patients undergoing TKA are accompanied by inflammatory response,which can aggravate pain,and severe pain can promote the occurrence of inflammatory response.The levels of Tumor Necrosis Factor-?(TNF-?)and Interleukin-6(IL-6)are related to the severity of tissue damage caused by noxious stimulation.It can be used as a good indicator of inflammatory reaction after suegery.It has been shown that peripheral nerve block can reduce the concentration of TNF-? and IL-6 during perioperative period,and the alleviation of inflammatory reaction can enhance perioperative analgesia.Objective:This study is intended to observe the analgesic effect of ultrasoundguided continuous adductor block(CACB)combined with sciatic nerve block(SNB)and obturator nerve block(ONB)and the concentration of TNF-? and IL-6 in the early postoperative period for the patients undergoing total knee arthroplasty.Provide a theoretical basis for clinical applications.Methods:80 patients of both sexes,aged 50~80yr,of American Society of Anesthesiologists I ~ II,scheduled for elective unilateral total knee arthroplasty,were randomly allocated to 2 groups(n=40): A group:CACB combined with SNB and ONB group,B group: CACB combined with LIA group.Nerve block was performed before induction of general anesthesia in both groups.Group B performed local infiltration anesthesia during surgery.The consumption of sufentanil and remifentanil intraoperative was recorded.At leaving the recovery room,3h,6h,24 h,48h,72 h after surgery,VAS scare at rest and during activity were recorded.At 24 h,48h,72 h,1 week after surgery,the range of motion of knee joint was measured.And the requirement for analgesic drugs and postoperative adverse reactions were recorded.Preoperative and postoperative venous blood samples were collected at 3h?6h?24h?48h before and after surgery and Enzyme-linked immunosorbent assay(ELISA)was used to detect the concentration of TNF-? and IL-6.Results:The total intravenous remifentanil consumption perioperative was less in the A group compared with B group(P < 0.05)?The VAS scores was lower in the A group at rest at postoperative 6h,24 h,48h and during activity at postoperative leaving the recovery room?3h?6h?24h?48h?72h(P < 0.05).The TNF-? and IL-6 concentration in group A was significantly lower than that in group B at 3h,6h,24 h and 48 h after surgery(P < 0.05).The range of motion of knee joint in group B was greater than that in group A at postoperative 24 h,with significant difference(P < 0.05).The cases of vomiting in group A was lower than in group B,with no significant difference(P > 0.05).Conclusion:Adductor canal block combined with sciatic nerve block and obturator nerve block is beneficial for early functional rehabilitation,which has a significant effect on postoperative analgesia and reduction consumption of opioids.In addition,it reduces postoperative inflammation reaction.