Maurer Konrad, Blumenthal Stephan, Rentsch Katharina M, Schmid Edith R
Division of Cardiovascular Anesthesia, University Hospital of Zurich, Zurich, Switzerland.
J Cardiothorac Vasc Anesth. 2008 Apr;22(2):249-54. doi: 10.1053/j.jvca.2007.06.005. Epub 2007 Aug 22.
The pharmacokinetics of ropivacaine 0.2% were evaluated during a 48-hour continuous extrapleural infusion with 2 different infusion rates in patients undergoing cardiovascular surgery. The hypotheses that no toxic plasma concentrations of ropivacaine would be reached and that proportionality exists among plasma concentrations and dosage used were tested.
A prospective, randomized, nonblinded study.
The investigation was performed as a single-center study in the Division of Cardiovascular Anesthesia, University Hospital of Zurich, in Switzerland.
Seventeen consenting adults scheduled for elective cardiovascular surgery, with or without extracorporeal bypass, via the lateral thoracotomy approach were enrolled.
For postoperative pain relief, patients were randomly assigned to receive continuous extrapleural infusion of ropivacaine 0.2% at a rate of either 6 or 9 mL/h over 48 hours.
Plasma concentrations of ropivacaine reached toxic levels (>2.2 mg/L) in 25% of cases. No proportionality of plasma concentrations of ropivacaine existed when the 2 dosing regimens were compared.
Plasma concentrations of ropivacaine, administered at the given dose and rates during continuous extrapleural infusion, are unpredictable and may reach toxic levels in patients undergoing major cardiothoracic surgery.
在接受心血管手术的患者中，以两种不同输注速率进行48小时持续胸膜外输注期间，评估0.2%罗哌卡因的药代动力学。检验了不会达到罗哌卡因有毒血浆浓度以及血浆浓度与所用剂量之间存在比例关系的假设。
一项前瞻性、随机、非盲研究。
该研究在瑞士苏黎世大学医院心血管麻醉科作为单中心研究进行。
纳入了17名同意接受择期心血管手术的成年人，手术方式为经外侧开胸入路，有或无体外循环。
为缓解术后疼痛，患者被随机分配接受0.2%罗哌卡因以6或9 mL/h的速率持续胸膜外输注48小时。
25%的病例中罗哌卡因血浆浓度达到中毒水平（>2.2 mg/L）。比较两种给药方案时，罗哌卡因血浆浓度不存在比例关系。
在持续胸膜外输注期间，以给定剂量和速率给予罗哌卡因时，其血浆浓度不可预测，在接受大型心胸手术的患者中可能达到中毒水平。
