背景：對於接受全髖關節置換術(THA)和全膝關節置換術(TKA)的患者而言，脊髓麻醉具有許多優勢，但縱觀歷史，使用長效局部麻醉藥有下肢運動功能恢復緩慢且具有不可預測性的缺點。在這項前瞻性、雙盲、隨機的臨床試驗中，我們試圖確定接受初次THA和TKA的患者中，與小劑量布比卡因脊麻相比，局麻藥甲哌卡因是否能更平穩的恢復下肢運動功能。
方法：本試驗在同一學術機構進行，在試驗開始之前，一項內部預試驗研究確定需在154名患者中達到80%的療效。採用先進的計算機分層方法，根據手術過程、年齡、性別和體重指數，將患者按1:1的比例進行隨機化分組。手術結束後，使用Bromage評分於每15分鐘評估一次非手術下肢的運動功能，一旦Bromage評分達到0分(髖關節、膝蓋和踝關節的自發運動)，停止評分。
結果：接受甲哌卡因脊麻的患者與接受小劑量布比卡因的患者相比，下肢運動功能恢復更具預見性。在接受甲哌卡因麻醉的患者中，1%的患者在5小時後恢復了運動功能，而接受布比卡因麻醉的患者中只有11%的患者恢復了運動功能(p=0.013)。接受甲哌卡因麻醉的患者下肢運動功能恢復的平均時間(185min、95%CI、174~196min)比小劑量布比卡因組(210min、95%CI、193min~228min)快26分鐘(p=0.016)。與小劑量布比卡因相比，接受甲哌卡因麻醉的患者在疼痛評分、理療時間、直立性低血壓的發生率、尿瀦留或暫時性神經系統症狀等安全結果方面沒有顯著差異。
結論：在初次接受THA和TKA的患者中，與小劑量布比卡因相比，使用甲哌卡因腰麻可使下肢運動功能更平穩恢復，而不會增加脊麻藥物相關的併發症。這對短期住院和門診手術更具有價值。
原始文獻來源:Wyles CC, Pagnano MW, Trousdale RT, et al.More Predictable Return of Motor Function with Mepivacaine Versus Bupivacaine Spinal Anesthetic in Total Hip and Total Knee Arthroplasty: A Double-Blinded, Randomized Clinical Trial.[J].J Bone Joint Surg Am 2020 Sep 16;10218(18).
More Predictable Return of Motor Function with Mepivacaine Versus Bupivacaine Spinal Anesthetic in Total Hip and Total Knee Arthroplasty: A Double-Blinded, Randomized Clinical Trial
ABSTRACT
Background:Spinal anesthesia provides several benefits for patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA), but historically comes at the cost of slow and unpredictable return of lower-extremity motor function related to the use of long-acting local anesthetics. In this prospective, double-blinded, randomized clinical trial we sought to determine if an alternative local anesthetic, mepivacaine, would allow more consistent return of motor function compared with low-dose bupivacaine spinal anesthesia during primary THA and TKA.
Methods:This trial was conducted at a single academic institution. Prior to trial initiation an internal pilot study determined that 154 patients were required to achieve 80% power. Patients were randomized in a 1:1 fashion with use of advanced computerized stratification based on procedure, age group, sex, and body mass index. Following the surgical procedure, motor function was assessed every 15 minutes in the nonoperative lower extremity according to the Bromage scale and discontinued once Bromage 0 was achieved (spontaneous movement at hip, knee, and ankle).
Results:Return of lower-extremity function was more predictable in patients who received mepivacaine than in those who received low-dose bupivacaine. Among patients who received mepivacaine, 1% achieved motor function return beyond 5 hours compared with 11% of patients who received bupivacaine (p = 0.013). The mean time to return of lower-extremity motor function was 26 minutes quicker in patients who received mepivacaine (185 minutes; 95% confidence interval, 174 to 196 minutes) compared with low-dose bupivacaine (210 minutes; 95% confidence interval, 193 to 228 minutes) (p = 0.016). There were no significant differences in safety outcomes including pain scores, time to participation in physical therapy, incidence of orthostatic hypotension, urinary retention, or transient neurologic symptoms in patients receiving mepivacaine compared with low-dose bupivacaine.
Conclusions:In patients undergoing primary THA and TKA, spinal anesthesia with mepivacaine allowed more consistent return of lower-extremity motor function compared with low-dose bupivacaine, without a concomitant increase in complications potentially associated with spinal anesthetics. This is particularly of value in an era of short-stay and outpatient surgical procedures.