Kumar Vijay, Chapman John R
Thermogenesis Corp., Rancho Cordova, CA 95742, USA.
J Extra Corpor Technol. 2007 Mar;39(1):18-23.
Thrombin-based clotting agents currently used for topical hemostasis with absorbable sponges, fibrin sealants, and platelet gels are primarily derived from bovine or pooled human plasma sources. Autologous thrombin has important safety advantages in that it does not carry the same safety concerns as pooled plasma-derived products and it avoids exposure to risks associated with bovine-derived proteins. The goal of our research was to develop a rapid, reliable, and simple to perform process to generate autologous human thrombin in the intraoperative setting, from patient whole blood as the starting source material. Using whole blood instead of plasma as the starting material, it is possible to avoid the inherent delay in thrombin availability associated with a primary step of plasma isolation. In this study, we varied several key processing parameters to maximize thrombin production, reproducibility and stability. Autologous thrombin production was generated using a dedicated, single use disposable with a sterile reagent. The disposable consists of a tubular reaction chamber containing glass microsphere beads to activate the alternative pathway of the coagulation cascade. At the end of the process, thrombin-activated serum was harvested from the reaction chamber. The average activity of the thrombin produced at room temperature by this system was 82.8 +/- 15.9 IU/mL. The total processing time was < 30 minutes. The system was compatible with Anticoagulant Citrate Dextrose-Solution A (ACD-A) (8%-12%). The average volume of thrombin harvested from each aliquot of blood was 7.0 +/- 0.3 mL, and the stability of thrombin was observed to be temperature dependent, with cold storage better preserving thrombin activity. Clot times with platelet concentrates at 1:4.3 and 1:11 ratios (thrombin to platelet concentrate) were < 10 and 20 seconds, respectively. A process for the preparation of thrombin from whole blood, under conditions compatible with the resources of an operating room, has been developed. The device is simple to use, requires 30 minutes, and can consistently produce thrombin solutions that achieve rapid clotting of platelet concentrates, plasma, and fibrinogen concentrates even when mixed at thrombin to blood product ratios of 1:11.
目前用于与可吸收海绵、纤维蛋白密封剂和血小板凝胶一起进行局部止血的基于凝血酶的凝血剂主要来源于牛或混合人血浆。自体凝血酶具有重要的安全优势，因为它不存在与混合血浆衍生产品相同的安全问题，并且避免了接触与牛源蛋白相关的风险。我们研究的目标是开发一种快速、可靠且易于操作的方法，在术中环境下以患者全血作为起始原料来生成自体人凝血酶。使用全血而非血浆作为起始原料，可以避免与血浆分离这一主要步骤相关的凝血酶可用性的固有延迟。在本研究中，我们改变了几个关键的处理参数，以最大化凝血酶的产量、重现性和稳定性。自体凝血酶的产生使用了一种专用的、一次性使用的无菌试剂。该一次性用品由一个管状反应室组成，其中含有玻璃微球珠以激活凝血级联反应的替代途径。在该过程结束时，从反应室中收获凝血酶激活的血清。该系统在室温下产生的凝血酶的平均活性为82.8±15.9 IU/mL。总处理时间<30分钟。该系统与抗凝枸橼酸盐葡萄糖溶液A（ACD-A）（8%-12%）兼容。从每份血液等分试样中收获的凝血酶的平均体积为7.0±0.3 mL，并且观察到凝血酶的稳定性取决于温度，冷藏能更好地保存凝血酶活性。凝血酶与血小板浓缩物的比例为1:4.3和1:11时（凝血酶与血小板浓缩物），凝块形成时间分别<10秒和20秒。已经开发出一种在与手术室资源相兼容的条件下从全血制备凝血酶的方法。该装置使用简单，需要30分钟，并且即使在凝血酶与血液制品比例为1:11混合时，也能始终如一地产生能够使血小板浓缩物、血浆和纤维蛋白原浓缩物快速凝固的凝血酶溶液。
