Active Membrane for Artificial Lung Applications

项目总结/摘要 肺病每年在全世界造成300多万人死亡，40万美国人死亡（每6例死亡中就有1例）。 全球有超过2.35亿人和3500万美国人患有慢性肺病。 美国有超过20万人患有成人呼吸窘迫综合征（ARDS）， 率为25 - 40%。传统的呼吸支持方法是机械通气 肺虚和支持呼吸功能。但是高气道压高含氧量 注意力集中和过度膨胀可引起许多并发症，可能导致多器官衰竭。的 慢性病的医疗支持可以是氧疗和肺血管扩张剂，但长期 治疗最终是肺移植。人工肺技术，最常用于 已经开发和修改了在心脏直视手术期间的心肺转流，以提供 呼吸支持与急性以及慢性肺病患者。然而，目前的临床使用 便携式人工肺仅限于ICU中的体外膜肺氧合（ECMO）， 支持患者休息时的呼吸需求。真正的便携式或长期（>天）支持系统是 由于气体交换性能低和生物相容性问题，目前的技术无法提供。 人工肺中的一个至关重要的元件是气体（O2和CO2）交换的介入膜 发生在气体和血液之间交换机制是非常缓慢的扩散， 流和膜。该建议旨在攻击气体交换（扩散）的基本机制。 通过使用活性膜（AM）的创新概念。上午产生强烈的交叉流，正常的， 膜表面，从而搅动层流血流，并最终使气体的量子飞跃 交易所交叉流直接将质量（溶解O2/CO2的实体）从膜输送到膜 比分子扩散快几个数量级，就像传送带一样。因此，该系统不会 需要天然肺中发现的如此高的表面积，最终消除了许多复杂的问题， 在自然肺模拟中遇到的按比例放大的制造和集成。此外，减少 表面积将使对外来表面的炎症反应和最终凝血最小化。 本项目将重点通过体外血流测试证明AM的拟议概念。详细的任务计划 是（1）设计和优化活性膜沿着与CFD（计算流体动力学）分析;（2） 微制造优化的AM并将其集成到流动回路中;（3）体外评估气体交换 血液相容性研究中的水/血流回路性能。本项目的主要创新之处在于 是开发一种新的AM类，以取代现有的基于扩散的人工肺传输机制。的 这项工作的意义是在气体交换方面取得了巨大的飞跃， 高效的人工肺

Project Summary/Abstract Lung disease annually kills more than 3 million people worldwide and 400,000 Americans (1 out of 6 deaths). More than 235 million people worldwide and 35 million Americans are suffering from chronic lung disease. Over 200,000 American people are suffering from ARDS (adult respiratory distress syndrome) with its mortality rate of 25 - 40%. The traditional respiratory support for ARDS is mechanical ventilation to compensate pulmonary deficiency and to support respiratory function. However, high airway pressure, high oxygen concentration and over-distention can cause many complications, possibly resulting in multi-organ failure. The medical support for the chronic disease can be oxygen therapy and pulmonary vasodilators but the long-term treatment is ultimately lung transplantation. Artificial lung technologies, which are most commonly used for cardiopulmonary bypass during open-heart surgery, have been developed and modified in order to provide respiratory support with the acute as well as chronic lung disease patients. However, the current clinical use of portable artificial lung is very limited to only extracorporeal membrane oxygenation (ECMO) in ICU, only supporting the respiratory needs of patients at rest. Truly portable or long-term (> days) support systems are not available with current technologies due to low gas exchange performance and biocompatibility issues. A crucially important element in artificial lung is the intervened membrane where gas (O2 and CO2) exchange occurs between gas and blood streams. The exchange mechanism is extremely slow diffusion across the streams and membrane. This proposal aims to attack the fundamental mechanism in gas exchange (diffusion) by using an innovative concept of active membrane (AM). The AM generates strong cross-streams, normal to the membrane surface, thus agitates the laminar blood stream, and eventually make a quantum leap in gas exchange. The cross-streams directly carry mass (O2-/CO2-dissolved entities) from and to the membrane orders of magnitude faster than molecular diffusion, like a conveyer belt. As a result, this system would not require such a high surface area as found in natural lungs, eventually eliminating many complex issues of scale-up fabrication and integration encountered in natural lung mimicking. Furthermore, the decreased surface area would minimize inflammatory response to the foreign surface and eventually clotting. This project will focus on proving the proposed concept of AM via in vitro blood flow testing. Detailed task plans are (1) design and optimize active membranes along with CFD (computational fluid dynamics) analysis; (2) microfabricate optimized AMs and integrate them in flow loops; and (3) in vitro evaluate gas exchange performance in the water/blood flow loops with hemocompatibility study. The primary innovation of this project is to develop a new class of AMs to replace existing diffusion-based transport mechanism in artificial lung. The significance of this work is to make a quantum leap in gas exchange that allows for truly portable (wearable), highly efficient, artificial lungs.