Urzua J, Troncoso S, Bugedo G, Canessa R, Muñoz H, Lema G, Valdivieso A, Irarrazaval M, Moran S, Meneses G
Department of Anesthesiology, Catholic University of Chile School of Medicine, Santiago de Chile.
J Cardiothorac Vasc Anesth. 1992 Jun;6(3):299-303. doi: 10.1016/1053-0770(92)90144-v.
Controversy continues as to whether hypotension during cardiopulmonary bypass (CPB) impairs intraoperative and postoperative renal function. Therefore, 21 patients with normal renal function (plasma creatinine less than 1.2 mg/dL, creatinine clearance greater than 70 mL/min), aged 50 to 70 years, without associated pathology, scheduled for elective coronary surgery were studied prospectively. Patients were randomized into two groups: group 1 included 14 patients whose arterial blood pressure during CPB was left untreated, and group 2 consisted of 7 patients who received phenylephrine to maintain their arterial pressure above 70 mmHg. Plasma and urine creatinine, sodium, potassium, and osmolality were measured preoperatively, intraoperatively and postoperatively. Creatinine, osmolal and free water clearances, and excreted sodium fraction were calculated. Plasma creatinine remained normal throughout the study in all patients. Creatinine clearances were similar preoperatively (101.9 +/- 36.7 in group 1 and 120.6 +/- 50.7 mL/min in group 2). In group 1, creatinine clearance decreased during CPB to 88.7 +/- 39.7 mL/min, whereas in group 2 it increased to 157.6 +/- 79.5 mL/min; the difference between groups was significant. Early postoperatively, there was no difference: 136.2 +/- 86.6 mL/min in group 1 and 100 +/- 21.4 mL/min in group 2. One week postoperatively, values were 100.5 +/- 37.9 and 101.9 +/- 18.4, respectively. There was a significant correlation between the creatinine clearance and perfusion pressure intraoperatively, but not postoperatively. Osmolal clearance also correlated with perfusion pressure intraoperatively, but it was significantly lower in the phenylephrine group postoperatively. Postoperative renal function was normal in all patients; no deleterious effect of a low arterial pressure during bypass could be identified.
关于体外循环（CPB）期间的低血压是否会损害术中和术后肾功能，争议仍在继续。因此，对21例肾功能正常（血浆肌酐低于1.2mg/dL，肌酐清除率大于70mL/min）、年龄在50至70岁之间、无相关病变且计划进行择期冠状动脉手术的患者进行了前瞻性研究。患者被随机分为两组：第1组包括14例CPB期间动脉血压未予处理的患者，第2组由7例接受去氧肾上腺素以使动脉压维持在70mmHg以上的患者组成。术前、术中和术后均测量血浆和尿液中的肌酐、钠、钾及渗透压。计算肌酐、渗透和自由水清除率以及排钠分数。在整个研究过程中，所有患者的血浆肌酐均保持正常。术前肌酐清除率相似（第1组为101.9±36.7，第2组为120.6±50.7mL/min）。在第1组中，CPB期间肌酐清除率降至88.7±39.7mL/min，而在第2组中则升至157.6±79.5mL/min；两组之间的差异具有显著性。术后早期，两组无差异：第1组为136.2±86.6mL/min，第2组为100±21.4mL/min。术后1周，数值分别为100.5±37.9和101.9±18.4。术中肌酐清除率与灌注压之间存在显著相关性，但术后无相关性。渗透清除率在术中也与灌注压相关，但术后去氧肾上腺素组显著降低。所有患者术后肾功能均正常；未发现旁路期间低动脉压的有害影响。
