Smith Bradford B, Nuttall Gregory A, Mauermann William J, Schroeder Darrell R, Scott Phillip D, Smith Mark M
Department of Anesthesiology and Perioperative Medicine, Mayo Clinic College of Medicine and Science, Phoenix, Arizona.
Department of Anesthesiology and Perioperative Medicine, Mayo Clinic College of Medicine and Science, Rochester, Minnesota.
J Card Surg. 2020 May;35(5):1043-1050. doi: 10.1111/jocs.14532. Epub 2020 Apr 5.
Patients undergoing cardiac surgery requiring cardiopulmonary bypass (CPB) are at risk for coagulopathy and bleeding requiring blood product transfusion. Acute normovolemic hemodilution (ANH) is a blood conservation technique shown to reduce transfusion and bleeding associated with cardiac surgery. Despite numerous advantages, little is known about the effect of ANH on coagulation testing.
Prospective observational study, 80 patients (40 controls, 40 ANH) undergoing cardiac surgery requiring CPB. Blood for coagulation testing (hemoglobin, platelet count, prothrombin time/International Normalized Ratio [PT/INR], activated partial thromboplastin time [aPTT], fibrinogen, and kaolin thromboelastography [TEG]) was collected 5 minutes after protamine (Time 1), and following ANH reinfusion (or 30 minutes after Time 1) in controls (Time 2).
Patients undergoing ANH had a significantly lower aPTT (-1.4 seconds 95% CI [-2.7, 0.0]; P = .044) and higher fibrinogen (+13 mg/dL [+1, +26]; P = .040) between Time 1 and Time 2 compared to controls. Additionally, the change in hemoglobin between Time 1 and Time 2 was significantly increased in the ANH group (+0.4 [+0.1, +0.8]; P = .024). The study also demonstrated a normalization of the platelet count, PT/INR, aPTT, and TEG values between Time 1 and Time 2 in control patients.
In patients undergoing cardiac surgery requiring CPB, ANH results in significant improvements of aPTT, fibrinogen and hemoglobin values; however, the true clinical significance is questionable. In the absence of ongoing surgical bleeding, there appears to be normalization of coagulation tests (excluding fibrinogen) following CPB.
接受需要体外循环（CPB）的心脏手术的患者有发生凝血病和出血而需要输血的风险。急性等容血液稀释（ANH）是一种血液保护技术，已证明可减少与心脏手术相关的输血和出血。尽管有许多优点，但关于ANH对凝血检测的影响知之甚少。
前瞻性观察性研究，80例接受需要CPB的心脏手术的患者（40例对照，40例ANH）。在鱼精蛋白注射后5分钟（时间1）以及对照组在ANH再输注后（或时间1后30分钟）（时间2）采集用于凝血检测的血液（血红蛋白、血小板计数、凝血酶原时间/国际标准化比值[PT/INR]、活化部分凝血活酶时间[aPTT]、纤维蛋白原和高岭土血栓弹力图[TEG]）。
与对照组相比，接受ANH的患者在时间1和时间2之间aPTT显著降低（-1.4秒，95%置信区间[-2.7, 0.0]；P = 0.044），纤维蛋白原显著升高（+13mg/dL [+1, +26]；P = 0.040）。此外，ANH组在时间1和时间2之间血红蛋白的变化显著增加（+0.4 [+0.1, +0.8]；P = 0.024）。该研究还表明，对照组患者在时间1和时间2之间血小板计数、PT/INR、aPTT和TEG值恢复正常。
在接受需要CPB的心脏手术的患者中，ANH可显著改善aPTT、纤维蛋白原和血红蛋白值；然而，其真正的临床意义值得怀疑。在没有持续手术出血的情况下，CPB后凝血检测（不包括纤维蛋白原）似乎恢复正常。
