老年人实施轻比重蛛网膜下腔麻醉药物的剂量和安全性研究

Safety and Dose of Hypobaric Anesthetics in Spinal Anesthesia in Elderly Patients

目的探索60岁以上患者实施轻比重蛛网膜下腔阻滞的可行性及安全剂量范围。方法选取2006年9月—2012年9月于北京大学人民医院诊治,在轻比重蛛网膜下腔麻醉下行股骨粗隆间骨折闭合复位防旋股骨近端髓内钉（PFNA）内固定术的60岁以上患者146例,根据患者年龄将其分为60~79岁组（Ⅰ组,74例）和≥80岁组（Ⅱ组,72例）。两组患者均于L2~3或L3~4间隙行单次蛛网膜下腔穿刺或一点法腰硬联合阻滞,穿刺成功后,缓慢注入0.2%轻比重布比卡因。根据电子记录麻醉单检索并获取患者蛛网膜下腔麻醉前,麻醉后5、10、20、30、60 min及出室前的血压,布比卡因用量,麻醉平面,麻醉期间的输液量,是否采用旁正中入路,术中出血量,手术时间,根据电子病历系统检索并获取术后至出院期间所有新发的并发症。并采用Logistic回归分析影响蛛网膜下腔麻醉后低血压发生的可能危险因素。结果两组患者输液量、实施髂浅筋膜阻滞、采用旁正中入路、使用缩血管药物、术后并发症、麻醉平面、手术时间、术中出血量和术后住院时间比较,差异均无统计学意义（P〉0.05）;两组患者布比卡因剂量比较,差异有统计学意义（P〈0.05）。两组患者不同时间平均动脉压比较,差异无统计学意义（F交互=0.325,F组间=0.708,F时间=14.202;P交互=0.688,P组间=0.402,P时间〈0.001）。两组患者蛛网膜下腔麻醉后5、10、20、30、60min时平均动脉压均较蛛网膜下腔麻醉前下降（P〈0.05）。Logistic回归分析结果显示,蛛网膜下腔麻醉前收缩压和麻醉平面是蛛网膜下腔麻醉后血压下降的危险因素（P〈0.05）。结论对80岁及以上的患者实施轻比重蛛网膜下腔麻醉时,推荐剂量8~10 mg;60~79岁患者,推荐剂量9-12 mg。老年患者蛛网膜下腔麻醉后血压下降发生率高,需积极地进行缩血管药物治疗。

Objective To explore the feasibility of the application of hypobaric anesthetics to subarachnoid block and safe dose range in elderly patients over 60. Methods 146 patients over 60 years old with spinal anesthesia and having undergone intertrochanteric fractures operation were selected in Peking University People＇s Hospital from September 2006 to September 2012. They were divicled into two groups according to age ： group [ （ n = 74） aged 60 - 79, and group II （ n = 72） aged 1〉 80. Both groups slowly received 0. 2% hypobaric bupivacaine after a single dose of subarachnoid punctures in the clearance of L2-3 or L3_4 or combined spinal epidural anesthesia by one point method. The respective blood pressure before anesthesia, 5, 10, 20, 30, 60 minutes after anesthesia and after operation, dose of bupivacaine, level of anesthesia, transfusion quantities during anesthesia, use of paramedian approach or not, intra - operative blood loss, operation time were obtained by retrieving the electronic anesthesia data records. All the new postoperative complications were obtained by retrieving the electronic medical records system. The risk factors for following hypotension after spinal anesthesia were analyzed by Logistic regression. Results The differences in transfusion quantities, implementation of iliac fascia block, use of paramedian approach, use of vasoconstrictor drugs, postoperative complications, anesthesia level, operation time, intra - operative blood loss and hospital stay after operation were not significant between the two groups （P 〉 0. 05） ; the difference in dose of bupivacaine was significant （ P 〈 0. 05 ）. The differences of mean blood pressure at different time points were not significant between the two groups （ Finteration = 0. 325, Fintergroups = 0. 708, Ftime = 14. 202 ; Pinteraetion = 0. 688, Pintergroups = 0. 402, Ptime 〈 0. 001 ）. The mean pressure in both groups 5, 10, 20, 30, 60 rain after spinal anesthesia all decreased （P 〈0. 05）. Logistic regression analysis revealed systolic pressure and level of anesthesia were the risk factors for hypotension after anesthesia （ P 〈 0. 05 ）. Conclusion This study recommended dose of bupivacaine is 8 - 10 mg for patients over 80, and 9 - 12 mg for patients between 60 and 79. The incidence of spinal anesthesia induced hypotension is so high that active application of vasoconstrictor drugs is necessary.