Integration of Compliance Chambers into Diaphragm Displacement Pump to Double the Pumping Flow of Pediatric Paracorporeal Pulsatile Ventricular Assist Device

ParacorpoReal柏林心脏EXCOR是FDA批准的唯一一种用于 儿科病人。这种脉动隔膜柱塞泵(DDP)体积小/重量轻，便于儿科 耐心地走动。然而，EXCOR的效率只有50%，因为它以不同的速度抽出和泵血 次数(间断脉动流)。这会产生很高的峰值血流速度，这可能会导致血液损伤。 一种准心脏持续流动儿科VAD也已用于较小的儿童。这台离心泵 由于通过引流/输液插管的持续流动，效率很高，但PediMag泵的泵头 必须连接到笨重/笨重的马达，这会阻碍行走。我们之前开发出了一种经根尖到 主动脉(TAA)双腔插管(DLC)用于微创非卧床LVAD，效果良好 96小时初生羔羊的性能/血液相容性。我们的最终目标是开发一种高效的、最低限度的 为儿科患者设计的侵入性准心脏左冠状动脉成形术系统，它结合了小尺寸/重量(行走) 电流间断脉动流量泵(例如EXCOR)的电势)和电流的高效率 连续流泵(如PediMag)。使能技术是一种顺应式隔膜活塞泵 (CDDP)，它将顺应室集成到引流和输液出口，以使血流量加倍。 CDDP将是高性能的，因为：1)不间断/连续的血流；2)输液/引流 降低cDDP后负荷/增加cDDP预负荷的顺应室。较低高峰引流/输液 CDDP的流动也将减少血液创伤。初步数据显示，增加合规室 泵送流量由1 L/分钟增加到2 6 L/分钟，峰值流量降低。第一阶段SBIR的目标是 设计并制造了具有最佳顺应室尺寸的cDDP工作样机。这个cDDP将是 用我们之前开发的TAA DLC在羔羊身上进行了测试。具体目标1：设计、制造和测试 测试cDDP。顺应室将集成到cDDP引流和输液出口中。CDDP 将由聚碳酸酯外壳制成，中间带有聚氨基甲酸酯隔膜。三尖瓣可以 将cDDP外壳连接到两个小型硅胶顺应室。最终的原型将进行测试，以确定 在37%甘油模拟环路中1周，以获得性能/可靠性/耐用性。具体目标2：测试cDDP 在羔羊身上工作的原型。CDDP将与TAA DLC相结合，以形成侵入性较小的， 将在10-15公斤的羔羊(n=9)身上进行测试，以评估6小时性能/可靠性和 最初的生物相容性。原型设计/制造/台架测试将在W-Z生物技术公司进行，羔羊 研究将在肯塔基大学进行。我们的cDDP不是对现有技术进行微调，而是 一项新颖的发明，它将使搏动的准心脏VAD具有双倍的效率。这项技术可以 也可用于成人，并可能显著影响心源性休克/过渡到心脏移植治疗。

The paracorporeal Berlin Heart EXCOR is the only FDA-approved ventricular assist device (VAD) for pediatric patients. This pulsatile diaphragm displacement pump (DDP) is small/light weight to facilitate pediatric patient ambulation. However, EXCOR efficiency is only 50% since it withdraws and pumps blood at different times (interrupted pulsatile flow). This generates a high peak blood flow rate, which may cause blood damage. A paracorporeal continuous flow PediMag VAD has also been used in smaller children. This centrifugal pump is highly efficient due to the constant flow through the drainage/infusion cannulas, but the PediMag pump head must be attached to a bulky/heavy motor, which hinders ambulation. We previously developed a transapical to aorta (TAA) double lumen cannula (DLC) for a minimally invasive ambulatory LVAD, which showed excellent 96 hr performance/hemocompatibility in neonate lambs. Our ultimate goal is to develop an efficient, minimally invasive, paracorporeal LVAD system for pediatric patients, which combines the small size/weight (ambulation potential) of current interrupted pulsatile flow pump (e.g EXCOR) and the current high efficiency of a continuous flow pump (e.g PediMag). The enabling technology is a compliant diaphragm displacement pump (cDDP), which has compliance chambers integrated into the drainage and infusion outlets to double blood flow. The cDDP will be high performing due to: 1) noninterrupted/continuous blood flow; 2) infusion/drainage compliance chambers that decrease cDDP afterload/increase cDDP preload. The lower peak drainage/infusion flow of the cDDP will also reduce blood trauma. Preliminary data showed that adding compliance chambers increased pumping flow from 1.1 to 2.6 L/min and decreased peak flow rate. The Phase I SBIR objective is to design and fabricate a cDDP working prototype with optimal compliance chambers size. This cDDP will be tested in lambs with our previously developed TAA DLC. Specific Aim 1: To design, fabricate, and bench test a cDDP. Compliance chambers will be integrated into the cDDP drainage and infusion outlets. The cDDP will be made of polycarbonate housing with a polyurethane diaphragm in the middle. A tricuspid valve will connect the cDDP housing to the two small silicone compliance chambers. The final prototype will be tested for 1 week in a 37% glycerin mock loop for performance/reliability/durability. Specific Aim 2: To test the cDDP working prototype in lambs. The cDDP will be combined with the TAA DLC to form a less invasive, ambulatory LVAD, which will be tested in 10-15 kg lambs (n=9) to evaluate 6 hr performance/reliability and initial biocompatibility. Prototype design/fabrication/bench testing will be done at W-Z Biotech, and the lamb studies will be done at the University of Kentucky. Rather than fine-tuning existing technology, our cDDP is a novel invention, which will enable a pulsatile paracorporeal VAD with doubled efficiency. This technology can also be used in adults and may significantly impact cardiogenic shock/bridge to heart transplant management.