非停跳冠状动脉搭桥患者早期不同入液量对搭桥期间血流动力学及组织氧合的影响

Effects of different fluid volume on hemodynamics and tissue oxygenation during early stage of off-pump coronary artery bypass grafting

摘要:

目的  观察非停跳冠状动脉搭桥（OPCABG）患者早期不同入液量对搭桥期间血流动力学及组织氧合的影响。方法  将OPCABG患者随机分为两组，每组20例。常规麻醉诱导和维持。从入室至游离乳内动脉前，A组以2～3 ml/（kg·h）、B组以5～7 ml/（kg·h）的速度输注生理盐水。记录患者术前（T0）、游离乳内动脉前（T1）、前降支远端吻合（T2）、右冠状动脉远端吻合（T3）、回旋支远端吻合（T4）、搭桥结束患者体位调至水平后（T5）各时间的平均动脉压（MAP）、心率（HR）、心输出量（CO）、每搏量变异度（SVV）、中心静脉压（CVP）。T1和T4时的中心静脉血氧饱和度（ScvO2）、动脉血乳酸，T0～T5时患者去甲肾上腺素（NE）和肾上腺素（E）总用量、尿量，入监护室后第1天的血乳酸峰值、肌酐峰值。结果  两组患者年龄、性别、体重、左室射血分数、术前心梗例数、手术时间以及T0与T1时血流动力学指标比较，差异无统计学意义。A组患者T2、T4、T5时MAP明显低于T0（P <0.05），T4、T5时MAP低于B组，差异无统计学意义。T2～T5时A组HR明显低于B组（P<0.05）。搭桥期间两组CO明显低于术前（P <0.05），T2～T4时A组CO逐渐下降，而B组CO无明显波动，T3～T5时B组CO高于同时间的A组（P <0.05）。两组CVP在T2～T4随时间推移呈逐渐上升趋势，明显高于术前水平（P <
0.05），T2时A组患者CVP高于B组（P <0.05）。两组SVV变化无明显规律。A组患者术中应用血管活性药物总量、T4时乳酸水平、监护室乳酸峰值高于B组（P <0.05），T4时ScvO2低于B组（P <0.05）。术中尿量明显少于B组，术后早期肌酐峰值高于B组（P <0.05）。结论  搭桥前轻度限制液体输入，达到早期目标导向性液体治疗目标，在搭桥期间维持血流动力学平稳、保证组织灌注和氧供、减少血管收缩药的依赖性方面具有明显优势。

Abstract:

Objective To observe the effect of different fluid volume on hemodynamics and tissue oxygenation in the early stage of off-pump coronary artery bypass grafting (OPCABG). Methods Patients with OPCABG were randomly divided into groups A and B with 20 cases in each group. Anesthesia induction and maintenance were conducted routinely. Patients were infused with normal saline at the speed of 2-3 ml/(kg·h) in the group A and 5-7 ml/(kg·h) in the group B from the time of entering the operation room to the free of internal mammary artery. Patients' mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), stroke volume variation (SVV) and central venous pressure (CVP) were recorded at six time points including the time of entering the operation room (T0), before the free of internal mammary artery (T1), at the anastomosis of anterior descending branch (T2), the anastomosis of the distal end of right coronary artery (T3) and distal end of circumflex coronary artery (T4), and immediatly after anastomosis of all the arteries (T5). Central venous oxygen saturation (ScvO2) and arterial lactate were recorded at T1 and T4. The urine volume and the total amount of norepinephrine (NE) and epinephrine (E) used from T0 to T5 were summarized. The peak values of arterial lactate and creatinine on the first day in the Intensive Care Unit were also recorded. Results There were no significant differences between both groups in age, sex, body weight, left ventricular ejection fraction, the case number of preoperative myocardial infarction, operation time or the hemodynamic indexs at T0 and T1. MAP at T2, T4 and T5 was significantly lower than that at T0 in the group A. Athough MAP of the group A at T4 and T5 was lower than that of the group B, there was no statistical difference. From T2 to T5, HR in the group A was significantly lower than that in the group B (P < 0.05). CO of the patients in both groups during bypass grafting was significantly lower than the preoperative level (P < 0.05); while CO decreased gradually from T2 to T4 in the group A, but had no significant fluctuation in the group B. CO in the group B from T3 to T5 was significantly higher than that in the group A (P < 0.05). CVP of both groups increased gradually from T2 to T4, and was significantly higher than the preoperative level (P < 0.05); while CVP of the group A at T2 was significantly higher than that in the group B. The changes of SVV in both groups had no obvious rule. The total amount of vasoactive drugs (T0-T5), lactate level at T4 and the peak values of arterial lactate in the group A were much higher than those in the group B (P < 0.05). ScvO2 at T4 in the group A was lower than that in the group B (P < 0.05). The urine volume (T0-T5) was significantly smaller and the peak value of creatinine on the first postoperative day was significantly higher in the group A than those in the group B (P < 0.05). Conclusions Mild restriction of fluid input before OPCABG can basically achieve the goals of early directed fluid therapy, and has significant advantages in the maintenance of stable hemodynamics, tissue oxygen supply, and reduction of vasoactive drugs during coronary bypass grafting.