Hogue C W, Goodnough L T, Monk T G
Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.
Transfusion. 1998 Oct;38(10):924-31. doi: 10.1046/j.1537-2995.1998.381098440856.x.
The anemia associated with perioperative blood conservation has raised concerns regarding the safety of these strategies in patients with ischemic cardiovascular disease. Therefore the relationship between hematocrit level and myocardial ischemic episodes in a group of elderly patients undergoing elective noncardiac surgery was studied.
One hundred ninety patients undergoing radical prostatectomy were randomly assigned to one of three blood conservation groups: preoperative autologous blood donation, acute normovolemic hemodilution, and preoperative erythropoietin therapy with acute normovolemic hemodilution. Patients underwent ambulatory electrocardiography monitoring to evaluate for myocardial ischemia at randomization (baseline), 7 days preoperatively, throughout surgery, and for 24 hours after surgery.
Myocardial ischemic episodes occurred in 61 (34%) of 181 evaluable patients. Patients with hematocrit levels < 28 percent immediately after surgery were significantly (p = 0.05) more likely to have intraoperative and postoperative ECG ischemic episodes. Intraoperative ischemia and tachycardia correlated (r = 0.21, p = 0.008) with hematocrit levels. Hematocrit levels after surgery were associated with postoperative ischemia (r = 0.14, p = 0.03) and duration of myocardial ischemic episodes (r = 0.14, p = 0.04). After adjusting for other risk factors, intraoperative tachycardia episodes, hematocrit level < 28 percent immediately after surgery, and risk factors for coronary artery disease were independently associated with the likelihood of intraoperative ischemia (r = 0.36, p = 0.002, area under receiver operating characteristic curve = 0.73). Similarly, tachycardia episodes and hematocrit levels < 28 percent immediately after surgery were independently associated with ischemic episodes during the first postoperative day (r = 0.30, p = 0.004, area under receiver operating characteristic curve = 0.71).
A hematocrit level < 28 percent is independently associated with risk for myocardial ischemia during and after noncardiac surgery. Avoidance of cardiac complications may require higher transfusion thresholds, closer attention to tachycardia, or better monitoring for ischemia.
围手术期血液保护相关的贫血引发了人们对这些策略在缺血性心血管疾病患者中安全性的担忧。因此，研究了一组接受择期非心脏手术的老年患者的血细胞比容水平与心肌缺血发作之间的关系。
190例接受根治性前列腺切除术的患者被随机分配到三个血液保护组之一：术前自体血捐献、急性等容血液稀释以及术前促红细胞生成素治疗联合急性等容血液稀释。患者在随机分组时（基线）、术前7天、整个手术过程以及术后24小时接受动态心电图监测以评估心肌缺血情况。
181例可评估患者中有61例（34%）发生心肌缺血发作。术后即刻血细胞比容水平<28%的患者发生术中及术后心电图缺血发作的可能性显著更高（p = 0.05）。术中缺血和心动过速与血细胞比容水平相关（r = 0.21，p = 0.008）。术后血细胞比容水平与术后缺血相关（r = 0.14，p = 0.03）以及心肌缺血发作持续时间相关（r = 0.14，p = 0.04）。在调整其他危险因素后，术中心动过速发作、术后即刻血细胞比容水平<28%以及冠状动脉疾病危险因素与术中缺血的可能性独立相关（r = 0.36，p = 0.002，受试者工作特征曲线下面积 = 0.73）。同样，心动过速发作和术后即刻血细胞比容水平<28%与术后第一天的缺血发作独立相关（r = 0.30，p = 0.004，受试者工作特征曲线下面积 = 0.71）。
血细胞比容水平<28%与非心脏手术期间及术后心肌缺血风险独立相关。避免心脏并发症可能需要更高的输血阈值、更密切关注心动过速或更好地监测缺血情况。
