Wallock M, Arentzen C, Perkins J
Department of Cardiovascular Surgery, Evanston Hospital, IL 60201, USA.
Perfusion. 1995;10(1):13-6. doi: 10.1177/026765919501000103.
Factor XII initiates the intrinsic coagulation cascade and may affect the fibrinolytic system. Routine coagulation tests used during cardiopulmonary bypass (CPB) are abnormal in factor-XII-deficient patients and are useless for monitoring anticoagulation in these patients. A factor-XII-deficient patient requiring CPB is described. The baseline celite activated clotting time (ACT) was greater than 1400 seconds and the thrombin time was 12.4 seconds (control, 11.9 seconds). Two units of plasma were given resulting in an ACT of 173 seconds. Following 300 units/kg of heparin and during CPB, the ACT ranged from 670-596 seconds with the thrombin time greater than 200 seconds. Plasma provides exogenous factor XII allowing an endpoint on the ACT test and may protect against possible postoperative hypofibrinolytic complications. A commercially available modified thrombin time may also be useful and provide an endpoint during high-dose heparinization.
因子 XII 启动内源性凝血级联反应，并可能影响纤维蛋白溶解系统。在体外循环（CPB）期间进行的常规凝血试验在因子 XII 缺乏的患者中异常，并且对于监测这些患者的抗凝情况毫无用处。本文描述了一名需要进行体外循环的因子 XII 缺乏患者。基线硅藻土激活凝血时间（ACT）大于 1400 秒，凝血酶时间为 12.4 秒（对照为 11.9 秒）。输注两单位血浆后，ACT 为 173 秒。给予 300 单位/千克肝素后，在体外循环期间，ACT 范围为 670 - 596 秒，凝血酶时间大于 200 秒。血浆提供外源性因子 XII，使得 ACT 试验有一个终点，并且可能预防术后可能出现的低纤维蛋白溶解并发症。一种市售的改良凝血酶时间也可能有用，并在大剂量肝素化期间提供一个终点。
