Review articles : Extracorporeal membrane oxygenation (ECMO): prolonged bedside cardiopulmonary bypass

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68988/2/10.1177_026765919000500402.pd

A Novel Mock Circuit to Test Full-Flow Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) has become an important therapeutic approach in the COVID-19 pandemic. The development and research in this field strongly relies on animal models; however, efforts are being made to find alternatives. In this work, we present a new mock circuit for ECMO that allows measurements of the oxygen transfer rate of a membrane lung at full ECMO blood flow. The mock utilizes a large reservoir of heparinized porcine blood to measure the oxygen transfer rate of the membrane lung in a single passage. The oxygen transfer rate is calculated from blood flow, hemoglobin value, venous saturation, and post-membrane arterial oxygen pressure. Before the next measuring sequence, the blood is regenerated to a venous condition with a sweep gas of nitrogen and carbon dioxide. The presented mock was applied to investigate the effect of a recirculation loop on the oxygen transfer rate of an ECMO setup. The recirculation loop caused a significant increase in post-membrane arterial oxygen pressure (paO2 ). The effect was strongest for the highest recirculation flow. This was attributed to a smaller boundary layer on gas fibers due to the increased blood velocity. However, the increase in paO2 did not translate to significant increases in the oxygen transfer rate because of the minor significance of physically dissolved oxygen for gas transfer. In conclusion, our results regarding a new ECMO mock setup demonstrate that recirculation loops can improve ECMO performance, but not enough to be clinically relevant

Introducing ECMO/ECLS in sub-Saharan Africa – prospects and perspectives

Background: The introduction of modern medical technologies reduced mortality in adults and increased survival in infants less than five years old. Cardiac and respiratory failure can be managed through mechanical circulatory support devices such as ECMO/ECLS (Extracorporeal Membrane Oxygenation/ Extracorporeal Life Support).Main Findings: We evaluate the importance and potential impact of using ECMO/ECLS in improving health care in sub-Saharan Africa. The intention of this recommendation is to introduce this concept as a feasible rescue method for clinicians in the region. The potential use of ECMO/ECLS will be discussed with focus on infrastructure for the retrieval services from the referring hospitals to designated ECMO centres.Conclusion: ECLS resources and time that should be committed to training of staff and on-going education should not be underestimated. ECLS should only be commenced, maintained and weaned in the hands of trained, experienced and knowledgeable medical personnel cognisant that the results will be benchmarked by ELSO (Extracorporeal Life Support Organization) and available for consumption in the public domain. Partnership models are key to the ECLS success with well-defined roles and responsibilities for each party. The possible way for ECMO/ECLS in Africa should be combining with a two-pronged education programme: Improving critical care services in themselves, and once they get to an acceptable level in this department then is to manage ECLS patients for a few hours. To upgrade critical care services, this is vital for Africa, and only then to introduce ECMO/ECLS

Clinical and Administrative Steps to the ECMO Program Development

Extra-corporeal membrane oxygenation (ECMO) is a rapidly evolving therapy for acute lung and/or heart failure. ECMO, from a technical standpoint, is conceptually simple—however, it can be very challenging to implement therapy at the individual patient level as well as at hospital (or healthcare system) level. ECMO program development involves engagement of key stake-holders including physicians, nursing, and administrative leadership. The goal of this chapter is to outline some of the crucial steps in developing a successful ECMO program including highlighting the necessary resources, team members and structure, and basic program structure and function

Triple Cannulation ECMO

Extracorporeal membrane oxygenation (ECMO) has emerged as an invaluable tool for bridging severe isolated or combined failure of lung and heart. Due to massive technical improvements, the application of ECMO is growing fast. While historically ECMO was initiated and maintained by cardiac surgeons, in recent times interventional cardiologists and intensive care specialists increasingly run ECMO systems independently with great success. Percutaneous ECMO circuits are usually set up in a dual cannulation mode, either as veno-venous or as veno-arterial configuration. A novel advanced strategy is the cannulation of three large vessels (triple cannulation), resulting in veno-veno-arterial or veno-arterio-venous cannulation. Both veno-venous and veno-arterio-venous cannulation may further be upgraded to veno-pulmonary-arterial or veno-arterial-pulmonary arterial cannulation, respectively. Triple cannulation expands the field of ECMO application but substantially increases the complexity of ECMO circuits. In this chapter, we review percutaneous dual and triple cannulation strategies, featuring a recently proposed unifying nomenclature. This unequivocal code universally applies to both dual and triple cannulation strategies (VV, VPa, VA, VVA, VAV, VAPa). The technical evolution of ECMO is growing fast, but it has to be noted that current knowledge of ECMO support is mainly based on observation. Thus controlled trials are urgently needed to prospectively evaluate different ECMO modes