A mock circulation loop to test extracorporeal CO2 elimination setups

Intensive Care Medicine Experimental

Ralf M. Muellenbach¹  Anna M. Jungmann²  Albert J. Omlor²  Leonie S. Schwärzel²  Quoc Thai Dinh²  Robert Bals²  Philipp M. Lepper²  Nicole Schmoll²  Frederik Seiler²  Joachim Schenk³ 

[1] Department of Anaesthesiology and Critical Care, Campus Kassel of the University of Southampton, Kassel, Germany;Department of Internal Medicine V - Pneumology and Intensive Care Medicine, University Hospital of Saarland, Kirrbergerstr. 1, 66421, Homburg, Germany;Department of Transfusion Medicine and Hemostaseology, University Hospital of Saarland, Homburg, Germany;

关键词: ECCOR;    Mock circulation;    ECMO;    ARDS;    COPD;   

DOI  :  10.1186/s40635-020-00341-z

来源: Springer

【 摘 要 】

BackgroundExtracorporeal carbon dioxide removal (ECCO2R) is a promising yet limited researched therapy for hypercapnic respiratory failure in acute respiratory distress syndrome and exacerbated chronic obstructive pulmonary disease. Herein, we describe a new mock circuit that enables experimental ECCO2R research without animal models. In a second step, we use this model to investigate three experimental scenarios of ECCO2R: (I) the influence of hemoglobin concentration on CO2 removal. (II) a potentially portable ECCO2R that uses air instead of oxygen, (III) a low-flow ECCO2R that achieves effective CO2 clearance by recirculation and acidification of the limited blood volume of a small dual lumen cannula (such as a dialysis catheter).ResultsWith the presented ECCO2R mock, CO2 removal rates comparable to previous studies were obtained. The mock works with either fresh porcine blood or diluted expired human packed red blood cells. However, fresh porcine blood was preferred because of better handling and availability. In the second step of this work, hemoglobin concentration was identified as an important factor for CO2 removal. In the second scenario, an air-driven ECCO2R setup showed only a slightly lower CO2 wash-out than the same setup with pure oxygen as sweep gas. In the last scenario, the low-flow ECCO2R, the blood flow at the test membrane lung was successfully raised with a recirculation channel without the need to increase cannula flow. Low recirculation ratios resulted in increased efficiency, while high recirculation ratios caused slightly reduced CO2 removal rates. Acidification of the CO2 depleted blood in the recirculation channel caused an increase in CO2 removal rate.ConclusionsWe demonstrate a simple and cost effective, yet powerful, “in-vitro” ECCO2R model that can be used as an alternative to animal experiments for many research scenarios. Moreover, in our approach parameters such as hemoglobin level can be modified more easily than in animal models.

【 授权许可】

CC BY