Gur O, Ege T, Gurkan S, Ozkaramanli Gur D, Karadag H, Cakir H, Duran E
Department of Cardiovascular Surgery, Namik Kemal University Medical Faculty, Tekirdag, Turkey.
J Cardiovasc Surg (Torino). 2012 Oct;53(5):665-9. Epub 2012 May 28.
Coronary artery bypass grafting (CABG) is one of the most common procedures performed to improve blood supply to myocardium. The characteristics of grafts, mechanical stress and pharmacological agents have substantial influence on the short and long term graft patency. Lidocaine is among the most frequently used antiarrhythmic agents perioperatively. The aim of this study was to evaluate the in vitro effects of lidocaine on internal mammarian artery (IMA), radial artery (RA) and saphenous vein (SV) grafts.
Using standard tissue bath techniques, responses to increasing concentrations of lidocaine hydrochloride were obtained, in segments of IMA, RA and SV grafts. Twenty patients were enrolled in the study with a total number of 48 grafts (16 for IMA, RA and SV grafts each). In vitro lidocaine concentrations between 10(-9)M and 10(-3.5)M were studied to represent therapeutic plasma concentration of 1.5-5 mcg/mL.
In IMA and RA grafts, lidocaine hydrochloride caused vasodilatation (40.5±1.9% and 39.1±2.6 % respectively) at concentrations between 10(-9) to 10(-7.5) M while causing a dose dependent vasoconstriction response at concentrations above 10(-7.5) M. In SV graft samples, lidocain hydrochloride caused vasodilatation (24.4±1.9 %) at concentrations between 10(-9) to 10(-7) M while causing dose dependent vasoconstriction at concentrations above 10(-7) M. For vasoconstriction effect, mean±SD values for E(max) were calculated as: 120.1±6.6% in IMA, 83.35±5.06% in RA, and 154.0±13.8% in SV. The vasoconstriction in the SV samples was higher than in the RA and IMA. The mean ±SD LogEC(50) values were -5.15±0.27, -5.76±0.11 and -5.56±0.19 for SV, IMA and RA grafts respectively.) There was a statiscally significant differences in the Log EC(50) values between SV, IMA and RA (P<0.005)
Based on the results of our study, we conclude that, increasing doses of lidocaine in the perioperative period may cause vasospasm in IMA, RA and SV grafts. Thus, avoiding high doses may have a role in improving perioperative and long term mortality.
冠状动脉旁路移植术（CABG）是改善心肌血液供应最常用的手术之一。移植物的特性、机械应力和药物制剂对移植物的短期和长期通畅率有重大影响。利多卡因是围手术期最常用的抗心律失常药物之一。本研究的目的是评估利多卡因对乳内动脉（IMA）、桡动脉（RA）和大隐静脉（SV）移植物的体外作用。
采用标准组织浴技术，获取IMA、RA和SV移植物段对盐酸利多卡因浓度增加的反应。20名患者参与本研究，共有48个移植物（IMA、RA和SV移植物各16个）。研究了10(-9)M至10(-3.5)M的体外利多卡因浓度，以代表1.5 - 5 mcg/mL的治疗血浆浓度。
在IMA和RA移植物中，盐酸利多卡因在10(-9)至10(-7.5)M浓度时引起血管舒张（分别为40.5±1.9%和39.1±2.6%），而在浓度高于10(-7.5)M时引起剂量依赖性血管收缩反应。在SV移植物样本中，盐酸利多卡因在10(-9)至10(-7)M浓度时引起血管舒张（24.4±1.9%），而在浓度高于10(-7)M时引起剂量依赖性血管收缩。对于血管收缩作用，E(max)的平均值±标准差计算如下：IMA中为120.1±6.6%，RA中为83.35±5.06%，SV中为154.0±13.8%。SV样本中的血管收缩高于RA和IMA。SV、IMA和RA移植物的平均±标准差LogEC(50)值分别为-5.15±0.27、-5.76±0.11和-5.56±0.19。SV、IMA和RA之间的Log EC(50)值存在统计学显著差异（P<0.005）
根据我们的研究结果，我们得出结论，围手术期增加利多卡因剂量可能导致IMA、RA和SV移植物血管痉挛。因此，避免高剂量可能对改善围手术期和长期死亡率有作用。
