Department of Anesthesiology, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada.
J Cardiothorac Vasc Anesth. 2011 Feb;25(1):78-84. doi: 10.1053/j.jvca.2010.03.007. Epub 2010 Jun 30.
Pulmonary arterial (PA) vasoconstriction in cardiac surgery can originate from the action of combined humoral, endothelial, and sympathetic tone changes. The consequence of PA vasoconstriction is pulmonary hypertension (PHT) and, when present after cardiopulmonary bypass (CPB), can predispose to right ventricular dysfunction. Right ventricular dysfunction after CPB is a serious complication with high mortality rates. The extent to which sympathetic blockade could reduce PA vasoconstriction and reduce PHT is unknown. Pharmacologic stellate ganglion block (SGB) has been associated with a reduction in PHT, but its role and mechanism in cardiac surgery have not been described. Thus, the goal of the study was to test the hypothesis that echo-guided left SGB, performed before the induction of general anesthesia, could prevent PA pressure increases during CPB weaning.
A prospective cohort study in cardiac surgical patients.
A tertiary care university hospital.
Forty cardiac surgical patients.
A left SGB was performed immediately before the induction of general anesthesia under ultrasound guidance and was compared with matched control patients. Standard hemodynamic and electrocardiographic monitoring was performed, and blood gas samples were drawn at specific predetermined time points for analysis. Rhythm disorders, echocardiographic parameters that included wall motion abnormalities, and biochemical parameters of myocardial ischemia were measured by an observer blinded to the allocated group.
Marked improvement in the PaO(2)/F(I)O(2) ratio in the SGB group was observed (mean difference = 77 mmHg, p = 0.0001). There were no differences between the groups in PA pressure over time during the procedure; central venous pressure was higher in the SGB group (p =0.0184). Reductions of right ventricular fractional area change (p = 0.0331) and tricuspid annulus displacement (p = 0.0048) were observed in the SGB group. The CK-MB was 1.5 times higher in the SGB group (p = 0.0211), but no patients developed myocardial infarction.
Left SBG was associated with improved oxygenation that could partially explain its mechanism in acute PHT. Further studies are necessary to evaluate the usefulness of this technique in patients with a high risk of PHT during separation from CPB.
心脏手术中的肺动脉（PA）血管收缩可能源于体液、内皮和交感神经张力变化的共同作用。PA 血管收缩的后果是肺动脉高压（PHT），并且在体外循环（CPB）后存在时，可能使右心室功能障碍易感性增加。CPB 后右心室功能障碍是一种严重的并发症，死亡率很高。交感神经阻滞在多大程度上可以减少 PA 血管收缩和降低 PHT 尚不清楚。药物性星状神经节阻滞（SGB）与 PHT 降低有关，但在心脏手术中的作用和机制尚未描述。因此，本研究的目的是检验以下假设，即在全身麻醉诱导前进行超声引导的左侧 SGB 可防止 CPB 脱机期间 PA 压力升高。
一项在心脏外科患者中的前瞻性队列研究。
一家三级护理大学医院。
40 名心脏外科患者。
在超声引导下，在全身麻醉诱导前立即进行左侧 SGB，并与匹配的对照组患者进行比较。进行标准的血流动力学和心电图监测，并在特定的预定时间点抽取血样进行分析。通过观察者对分配的组进行盲法测量心律失常、包括壁运动异常的超声心动图参数和心肌缺血的生化参数。
在 SGB 组中观察到 PaO2/FIO2 比值明显改善（平均差异=77mmHg，p=0.0001）。两组患者在手术过程中 PA 压力随时间的变化无差异；SGB 组的中心静脉压较高（p=0.0184）。在 SGB 组中，右心室分数面积变化（p=0.0331）和三尖瓣环位移（p=0.0048）减少。SGB 组的 CK-MB 高 1.5 倍（p=0.0211），但无患者发生心肌梗死。
左侧 SBG 与氧合改善相关，这可能部分解释了其在急性 PHT 中的作用机制。需要进一步研究来评估该技术在 CPB 分离期间发生 PHT 风险较高的患者中的有用性。
