Zhang Andrew, Haimowitz Brian J, Tharwani Kartik, Rojas-Peña Alvaro, Bartlett Robert H, Potkay Joseph A
Extracorporeal Life Support Laboratory, Department of Surgery, University of Michigan, Ann Arbor, MI 48109, USA.
VA Ann Arbor Healthcare System, Ann Arbor, MI 48105, USA.
Bioengineering (Basel). 2024 Sep 27;11(10):969. doi: 10.3390/bioengineering11100969.
Extracorporeal Carbon Dioxide Removal (ECCOR) systems support patients with severe respiratory failure. Concurrent ambulation and physical therapy improve patient outcomes, but these procedures are limited by the complexity and size of the extracorporeal systems and rapid changes in patient metabolism and the acid-base balance. Here, we present the first prototype of a wearable ECCOR system capable of adjusting to a patient's changing metabolic needs. Exhaust gas CO (EGCO) partial pressure is used as an analog for blood CO partial pressure (pCO). Twin blowers modulate sweep gas through the AL to achieve a desired target EGCO. The integrated system was tested in vitro for 24 h with water, under varying simulated metabolic conditions and target EGCO values, and in a single test with whole blood. When challenged with changing inlet water pCO levels in in vitro tests, the system adjusted the sweep gas to achieve target EGCO within 1 min. Control runs with a fixed sweep gas (without negative feedback) demonstrated higher EGCO levels when challenged with higher water flow rates. A single in vitro test with whole ovine blood confirmed functionality in blood. This is the first step toward wearable ECCOR systems that automatically respond to changing metabolism. Such devices would facilitate physical therapy and grant greater autonomy to patients.
体外二氧化碳清除（ECCOR）系统为严重呼吸衰竭患者提供支持。同时进行的步行和物理治疗可改善患者预后，但这些程序受到体外系统的复杂性和尺寸以及患者新陈代谢和酸碱平衡快速变化的限制。在此，我们展示了首个能够适应患者不断变化的代谢需求的可穿戴ECCOR系统原型。废气CO（EGCO）分压用作血液CO分压（pCO）的模拟值。双鼓风机调节通过气路的吹扫气体以达到所需的目标EGCO。该集成系统在体外用水进行了24小时测试，测试条件包括不同的模拟代谢状况和目标EGCO值，并进行了一次全血测试。在体外测试中，当进水pCO水平发生变化时，该系统在1分钟内调整吹扫气体以达到目标EGCO。在固定吹扫气体（无负反馈）的对照运行中，当水流速率增加时，EGCO水平更高。一次用全羊血进行的体外测试证实了该系统在血液中的功能。这是朝着能够自动响应代谢变化的可穿戴ECCOR系统迈出的第一步。此类设备将有助于物理治疗并赋予患者更大的自主性。
