Ohmura Shigeo, Sugano Akiko, Kawada Masayuki, Yamamoto Ken
Department of Anesthesiology and Intensive Care Medicine, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan.
Anesth Analg. 2003 Sep;97(3):893-897. doi: 10.1213/01.ANE.0000075838.91888.FE.
Local anesthetic toxicity produced by an inadvertent IV injection is attenuated by the pulmonary uptake of local anesthetics. We compared the pulmonary uptake of ropivacaine and levobupivacaine after a bolus injection in rabbits. Sixteen anesthetized rabbits were randomly assigned to either a ropivacaine group or a levobupivacaine group. A bolus containing ropivacaine or levobupivacaine 0.5 mg/kg and indocyanine green (an intravascular indicator) 0.25 mg/kg was injected rapidly into the vena cava. Arterial blood samples were collected serially at 1.2-s intervals for 30 s. Concentrations of local anesthetic and indocyanine green in each sample were determined for the calculation of first-pass uptake of a local anesthetic in the lung. The first-pass uptake of levobupivacaine (31.4% +/- 8.3%; mean +/- SD) was larger than that of ropivacaine (22.9% +/- 5.6%), and the maximum arterial concentration of ropivacaine (21.2 +/- 2.8 micro g/mL) was larger than that of levobupivacaine (18.6 +/- 1.9 micro g/mL). We conclude that the pulmonary uptake of levobupivacaine is larger than that of ropivacaine after a bolus injection. Therefore, the advantages of ropivacaine over levobupivacaine in terms of less cardiovascular toxicity may be offset by the smaller pulmonary uptake after an inadvertent IV injection.
静脉误注导致的局部麻醉药毒性可因局部麻醉药的肺摄取作用而减轻。我们比较了家兔单次注射后罗哌卡因和左旋布比卡因的肺摄取情况。16只麻醉家兔被随机分为罗哌卡因组或左旋布比卡因组。将含有0.5mg/kg罗哌卡因或左旋布比卡因以及0.25mg/kg吲哚菁绿（一种血管内指示剂）的单次剂量快速注入腔静脉。以1.2秒的间隔连续采集30秒的动脉血样本。测定每个样本中局部麻醉药和吲哚菁绿的浓度，以计算局部麻醉药在肺中的首过摄取量。左旋布比卡因的首过摄取量（31.4%±8.3%；平均值±标准差）大于罗哌卡因（22.9%±5.6%），且罗哌卡因的最大动脉血浓度（21.2±2.8μg/mL）大于左旋布比卡因（18.6±1.9μg/mL）。我们得出结论，单次注射后左旋布比卡因的肺摄取量大于罗哌卡因。因此，罗哌卡因在心血管毒性较小方面相对于左旋布比卡因的优势可能会因静脉误注后较小的肺摄取量而被抵消。
