Bartels_Hensley's Practical Approach to Cardiothoracic Anesthesia, 7e

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8. Extracorporeal Membrane Oxygenation for Pulmonary or Cardiac Support

FIGURE 8.3 Femoral venoarterial ECMO in the setting of impaired gas exchange. Reinfused oxygenated blood flows retrograde up the aorta (red arrow) and may meet resistance from antegrade flow from the native cardiac output (purple arrow), which, in the context of impaired native gas exchange, may lead to poor upper body oxygenation. ECMO, ex tracorporeal membrane oxygenation. (From Abrams D, Brodie D. Extracorporeal circulatory approaches to treat acute respiratory distress syndrome. Clin Chest Med . 2014;35(4):765-779. Reprinted with permission of Department of Surgery, Columbia University Irving Medical Center.)

Copyright © 2024 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. 3. Left ventricular venting: The retrograde flow of reinfused blood in the aorta in femo ral venoarterial ECMO may result in several adverse physiologic consequences related to an increase in left ventricular afterload. Increased left ventricular afterload increases wall stress, which both increases myocardial oxygen demand and decreases coronary arterial perfusion. Increased left ventricular afterload also leads to an increase in the end-diastolic volume, which may lead to acute pulmonary edema, along with stasis and risk of intracar diac thrombus formation, particularly when the aortic valve is not opening. Left ventricular venting—performed either percutaneously or surgically—mitigates each of these effects by decompressing the ventricle. Left ventricular venting (drainage) into the ECMO circuit also reduces the likelihood of upper-body hypoxemia in patients with impaired lung function.