Bevan J C, Reimer E J, Smith M F, Bridge H S, Martin G R, Bevan D R
Department of Anaesthesia, British Columbia's Children's Hospital, University of British Columbia, Vancouver, Canada.
Anesth Analg. 1998 Oct;87(4):772-8. doi: 10.1097/00000539-199810000-00006.
The purpose of this study was to compare the mivacurium infusion requirements and neuromuscular recovery in adults and children during propofol/opioid and sevoflurane anesthesia. Seventy-five adult and 75 pediatric patients were randomized to receive propofol/opioid 0.5 or 1.0 minimum alveolar anesthetic concentration (MAC) (age-related) sevoflurane anesthesia. Plasma cholinesterase (PChE) activity was measured. Neuromuscular blockade was monitored by train-of-four (TOF) stimulation every 10 s and adductor pollicis electromyography. A bolus of 2 x the 95% effective dose of mivacurium (0.25 mg/kg) was followed by an infusion titrated to maintain 90%-95% blockade. Mivacurium doses were recorded every 5 min. At the end of surgery, the infusion was stopped, and recovery from mivacurium was monitored until TOF > or =0.7. PChE concentrations were within the normal range (adults 4-12 KU/L, children 6-16 KU/L) and correlated with mivacurium dose. Mivacurium infusion rates were higher in children than in adults: at 30 min, the rates in children were 13.1 +/- 6.4, 8.1 +/- 4.7, and 5.2 +/- 2.9 microg x kg(-1) x min(-1) at 0, 0.5, and 1.0 MAC sevoflurane, respectively; the corresponding rates in adults were 5.9 +/- 3.1, 4.3 +/- 1.7, and 2.9 +/- 0.7 microg x kg(-1) x min(-1) (P < 0.01). Sevoflurane decreased mivacurium requirements, maximal decreases at 45 min in children and 10 min in adults, and delayed neuromuscular function recovery. Children recovered twice as quickly as adults, achieving TOF > or =0.7 at 9.8 +/- 2.5, 11.4 +/- 2.8, and 19.6 +/- 6.3 min compared with 19.9 +/- 5.4, 26.4 +/- 8.3, and 32.9 +/- 9.8 min in adults (P < 0.0001). In conclusion, mivacurium requirements were correlated with PChE, were greater in children than in adults, and were reduced by sevoflurane. Neuromuscular recovery occurred more rapidly in children and was delayed by sevoflurane.
The mivacurium infusion requirement to maintain constant 90%-95% neuromuscular block during anesthesia is correlated with plasma cholinesterase activity. It is increased in children and reduced by the inhaled anesthetic sevoflurane. Despite the larger dose administered to children, recovery from block occurred more rapidly in children than in adults and was delayed by sevoflurane.
本研究旨在比较成人和儿童在丙泊酚/阿片类药物及七氟醚麻醉期间米库氯铵的输注需求量及神经肌肉恢复情况。75例成年患者和75例儿科患者被随机分为接受丙泊酚/阿片类药物0.5或1.0最低肺泡有效浓度（MAC）（与年龄相关）的七氟醚麻醉。测定血浆胆碱酯酶（PChE）活性。每隔10秒通过四个成串刺激（TOF）和拇内收肌肌电图监测神经肌肉阻滞情况。先给予2倍米库氯铵95%有效剂量（0.25mg/kg）的推注量，随后进行输注滴定以维持90%-95%的阻滞。每5分钟记录米库氯铵剂量。手术结束时，停止输注，并监测米库氯铵的恢复情况直至TOF≥0.7。PChE浓度在正常范围内（成人4-12KU/L，儿童6-16KU/L），且与米库氯铵剂量相关。儿童的米库氯铵输注速率高于成人：在30分钟时，七氟醚浓度分别为0、0.5和1.0MAC时，儿童的输注速率分别为13.1±6.4、8.1±4.7和5.2±2.9μg·kg⁻¹·min⁻¹；成人相应的输注速率分别为5.9±3.1、4.3±1.7和2.9±0.7μg·kg⁻¹·min⁻¹（P<0.01）。七氟醚降低了米库氯铵的需求量，儿童在45分钟时最大降幅，成人在10分钟时最大降幅，并延迟了神经肌肉功能恢复。儿童恢复速度是成人的两倍，达到TOF≥0.7的时间分别为9.8±2.5、11.4±2.8和19.6±6.3分钟，而成人分别为19.9±5.4、26.4±8.3和32.9±9.8分钟（P<0.0001）。总之，米库氯铵需求量与PChE相关，儿童高于成人，且七氟醚可降低其需求量。儿童神经肌肉恢复更快，且七氟醚会延迟恢复。
麻醉期间维持90%-95%恒定神经肌肉阻滞所需的米库氯铵输注量与血浆胆碱酯酶活性相关。在儿童中增加，吸入麻醉药七氟醚可降低其需求量。尽管给予儿童的剂量更大，但儿童神经肌肉阻滞的恢复比成人更快，且七氟醚会延迟恢复。
