Imbelloni L E, Gouveia M A, Vieira E M, Cordeiro J A
Institute for Regional Anaesthesia, São José do Rio Preto, SP, Brazil.
Acta Anaesthesiol Scand. 2008 Nov;52(10):1327-30. doi: 10.1111/j.1399-6576.2008.01749.x.
Lidocaine has been used for spinal anaesthesia since 1948, seemingly without causing concern until recently. This study aimed at evaluating the feasibility of performing anorectal surgery in outpatient settings with low hypobaric lidocaine doses.
Three groups of 50 patients, physical status ASA I-II, undergoing anorectal surgical procedures in a prone jack-knife position, received 3 ml (18 mg), 4 ml (24 mg) or 5 ml (30 mg) of hypobaric 0.6% lidocaine. Sensory and motor blockade, time until first urination, ambulation, complications and the need for analgesics were evaluated. Patients were followed until the third post-operative day.
Adequate sensory block was obtained in all patients. Blockade was significantly lower in Group 1. The level at 15 min was L(1) with 3 ml, T(11) with 4 ml and T(10) with 5 ml. Only 24 patients presented a moderate motor block. There was no hypotension, nausea or vomiting, urine retention, transitory neurological symptom or post-dural puncture headache in any patients. There was one case of bradycardia with 4 ml and two cases with 5 ml.
Hypobaric lidocaine predominantly provided a sensory block after injection in the prone jack-knife position. The smallest dose (3 ml=18 mg) provides sufficient analgesia with a lesser dispersion and a shorter duration. The major advantages were haemodynamic stability and a high degree of patient satisfaction.
自1948年以来，利多卡因一直用于蛛网膜下腔麻醉，直到最近似乎都未引起关注。本研究旨在评估在门诊环境中使用低比重利多卡因进行肛肠手术的可行性。
三组各50例美国麻醉医师协会（ASA）身体状况分级为I-II级的患者，在俯卧折刀位接受肛肠手术，分别接受3毫升（18毫克）、4毫升（24毫克）或5毫升（30毫克）的0.6%低比重利多卡因。评估感觉和运动阻滞、首次排尿时间、行走情况、并发症及镇痛需求。对患者进行随访直至术后第三天。
所有患者均获得充分的感觉阻滞。第一组的阻滞效果明显较低。15分钟时的阻滞平面，3毫升组为L1，4毫升组为T11，5毫升组为T10。仅24例患者出现中度运动阻滞。所有患者均未出现低血压、恶心或呕吐、尿潴留、短暂性神经症状或硬膜穿刺后头痛。4毫升组有1例心动过缓，5毫升组有2例。
在俯卧折刀位注射后，低比重利多卡因主要产生感觉阻滞。最小剂量（3毫升 = 18毫克）可提供足够的镇痛效果，且扩散较小、持续时间较短。主要优点是血流动力学稳定和患者满意度高。
