Percutaneous Respiratory Assist Catheter

描述（由申请人提供）：每年有数十万美国人遭受短期肺衰竭，需要在重症监护室进行呼吸支持。本提案的目的是开发一种经皮呼吸辅助导管（PRAC），可插入静脉系统，为需要短期（约4-7天）呼吸辅助的患者提供独立于肺部的补充呼吸支持。PRAC将设计用于经皮插入外周静脉并放置在中心静脉系统中，在中心静脉系统中，PRAC将暴露于返回心脏的所有血液。PRAC将在纤维束内使用旋转叶轮，以产生血液的主动混合，从而增强气体交换。我们还将开发新型中空纤维膜，其中包含固定化酶，这将进一步加速CO2的去除。该项目的具体目标是：1.设计和评估新的混合叶轮结构，通过增加进入中空纤维束和中空纤维束内的流体运动来增加CO2去除。这些设计将使用计算流体动力学（CFD）进行开发。2.开发碳酸酐酶的酶涂层，以加速CO2去除并改善中空纤维膜的生物相容性。3.进行PRAC的急性（6小时）和慢性（7天）小牛植入，以评估气体交换、心血管影响和生物相容性。我们的目标是一种经皮辅助导管（20-25 Fr或更小），当用作急性肺衰竭（ARDS，肺炎）或慢性肺衰竭急性发作（COPD加重）患者现有治疗的辅助或替代时，可提供90-120 ml/min的CO2清除。每年有数十万美国人患有短期肺衰竭，需要住院治疗，以便为患者提供呼吸支持。目前用于为这些患者提供呼吸支持的方法具有与它们相关的问题和并发症。拟议的项目将开发一种简单的导管，可以插入病人的静脉，以提供呼吸支持，同时允许肺部休息和愈合。

DESCRIPTION (provided by applicant): Each year several hundred thousand Americans suffer short term lung failure requiring respiratory support within the intensive care unit. The objective of this proposal is to develop a percutaneous respiratory assist catheter (PRAC) that can be inserted into the venous system to provide supplemental breathing support, independent of the lungs, for patients requiring short-term (~ 4-7 day) respiratory assistance. The PRAC will be designed for percutaneous insertion into a peripheral vein and placement in the central venous system, where it will be exposed to all the blood returning to the heart. The PRAC will use a rotating impeller within the fiber bundle to generate active mixing of blood to enhance gas exchange. We will also develop novel hollow fiber membranes that incorporate immobilized enzymes that will further accelerate CO2 removal. The specific aims of the project are to: 1. Design and evaluate new mixing impeller structures that increase CO2 removal by increasing fluid motion into and within the hollow fiber bundle. The designs will be developed using computational fluid dynamics (CFD). 2. Develop an enzymatic coating of carbonic anhydrase to accelerate CO2 removal and improve the biocompatibility of hollow fiber membranes. 3. Perform acute (6 hour) and chronic (7 day) calf implants of the PRAC to assess gas exchange, cardiovascular impact, and biocompatibility. Our target is a percutaneous assist catheter (20-25 Fr or smaller) that can provide 90-120 ml/min of CO2 removal when used as an adjuvant or replacement to existing therapy for patients with acute lung failure (ARDS, pneumonia) or acute on chronic lung failure (COPD with exacerbation). PUBLIC HEALTH RELEVANCE several hundred thousand Americans each year suffer from short-term lung failure that requires hospitalization so that breathing support for the patient can be provided. The current methods for providing breathing support to these patients have problems and complications associated with them. The proposed project will develop a simple catheter that can be inserted into a patient's vein to provide breathing support while allowing the lungs to rest and heal.