Digital Microfluidics - Minimizing Blood Volume for Pediatric Coagulation Screening

摘要 数字微流控-儿科凝血筛查的最小血量(HL125484) 据报道，在接受心脏手术的新生儿中，高达20%会发生重大血栓事件。死亡率 在接受心脏手术的患者中，可能与儿童中风、肺栓塞或血栓形成有关 高达10%。除死亡率外，儿童血栓形成的发病率也很高，包括 长期住院和永久残疾。血栓形成风险增加的儿科患者 由于先天性或获得性高凝状态，需要个体化的抗凝治疗。一个 高凝状态小组既允许进行风险分层以指导治疗管理，也允许小组 目的：监测心脏外科手术中和术后的抗凝治疗。 有血栓家族史的儿科患者或有血栓家族史的 曾遭受重大血栓形成或血栓栓塞症的患者。低风险儿童的广泛筛查 患者是有争议的，因此不是这项建议的最佳目标人群。不幸的是，在那里 儿科中没有大型随机试验，因为进行检测需要大量的血液； 这是对收集解决这一争议所需数据的主要威慑。目前可用 筛查测试既昂贵又耗时，而且需要单独订购，需要大量血液。 样本。这些问题使得全面高凝状态的筛查和监测在临床上是不切实际的， 尤其是在接受心脏手术的高危儿童患者中。因此，迫切需要一种 廉价的高凝实验室面板，需要非常少量的血液，有一个快速的转变- 有可能在多个时间段应用于更多的潜在风险患者 在他们的手术治疗中。 这样的诊断面板可以通过采用数字微流控系统来实现。高凝血性试验 数字微流体盒将实现便携式自动化、快速周转时间和多路传输 分析，包括不同类型的分析(免疫分析和功能分析)，每个样本使用约350个NL样本 测试。采用数字微流控技术的一次性高凝板材检测用一次性药盒 对水滴的操纵将在一台小型仪器上使用。在第一阶段，我们成功地将 免疫测定(抗凝血酶III、蛋白C和纤溶酶原激活物抑制物-1)和功能测定(抗凝血酶III、蛋白C和纤溶酶原激活物抑制物-1) 凝血酶III、蛋白C、纤溶酶原、凝血因子VIII和凝血酶生成)安装在数字微流控芯片上。 在第二阶段，我们将在一个一次性试剂盒上对完整的亲血栓板进行多重检测， 进行全面的分析验证，并在波士顿儿童医院进行试点研究。这个 最终目标是开发一个单一的平台，可以执行多路免疫分析和 应用<50微米L全血进行功能测定以确定高凝状态的风险和指导 抗凝治疗，最初的重点是接受心脏手术的高危儿科患者。

ABSTRACT Digital Microfluidics – Minimizing blood volume for pediatric coagulation screening (HL125484) It is reported that up to 20% of neonates undergoing cardiac surgery suffer a major thrombosis event. Mortality related to pediatric stroke, pulmonary embolism, or thrombosis in patients undergoing cardiac surgery may be as high as 10%. In addition to mortality, the morbidity of pediatric thrombosis is significant, and includes prolonged hospitalization and permanent disability. Pediatric patients who are at increased risk for thrombosis due to either congenital or acquired hypercoagulability require individualized anticoagulation management. A hypercoagulability panel allows both risk stratification for guiding therapeutic management, as well as a panel to monitor anticoagulation therapy during and post cardiac surgical procedures. Screening for hypercoagulability is indicated in pediatric patients with a family history of thrombosis, or in those who have suffered a major thrombotic or thromboembolic event. Widespread screening of low risk pediatric patients is controversial, and therefore not an optimal target population for this proposal. Unfortunately, there are no large randomized trials in pediatrics due to the large volume of blood necessary to perform the testing; this is a major deterrent to collecting the data necessary to resolve this controversy. Currently available screening tests are expensive, time-consuming and ordered individually, requiring large volumes of blood sample. These issues make screening and monitoring for a full hypercoagulability panel clinically impractical, especially in high-risk pediatric patients undergoing cardiac surgery. Hence, there is a compelling need for an inexpensive hypercoagulability laboratory panel that requires very small volumes of blood, has a rapid turn- around time and has the potential to be applied to a larger number of potentially at-risk patients at multiple time points during their surgical management. Such a diagnostic panel is possible by employing a digital microfluidic system. Hypercoagulability tests on a digital microfluidic cartridge will enable portable automation, rapid turn-around time, and multiplexing several assays, including different types of assays (immunoassays and functional) utilizing about 350 nL sample per test. A disposable single-use cartridge for hypercoagulability panel testing using digital microfluidic manipulation of droplets will be used on a small form factor instrument. In Phase I, we successfully translated immunoassays (Anti-thrombin III, Protein C and Plasminogen Activator Inhibitor-1) and functional assays (Anti- thrombin III, Protein C, Plasminogen, Factor VIII and Thrombin generation) onto a digital microfluidic cartridge. In Phase II, we will multiplex the assays for a complete thrombophilia panel on a single disposable cartridge, perform comprehensive analytical validations, and conduct a pilot study at Boston Children's Hospital. The ultimate goal is the development of a single platform that can perform multiplexed immunoassays and functional assays using less than 50 µL whole blood sample to determine hypercoagulability risk and guide anticoagulation management, with initial emphasis on high-risk pediatric patients undergoing cardiac surgery.