Customize your JAMA Network experience by selecting one or more topics from the list below.
To the Editor We have read with great interest the report by Mustafa et al1 describing their venovenous extracorporeal membrane oxygenation (ECMO) experience in patients with severe coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome.1 Specifically, we commend their use of a dual-stage right atrium–to–pulmonary artery cannula, thereby promoting right ventricular (RV) support. Right ventricular dysfunction is a well-described complication of acute respiratory distress syndrome and is associated with increased mortality.2 Given the distinct pathophysiology involving the angiotensin-converting enzyme 2 receptor in combination with endothelial dysfunction, patients with COVID-19 acute respiratory distress syndrome may be at an increased risk of developing RV dysfunction.3 There have been multiple reports demonstrating RV failure in this particular patient population with abnormal RV longitudinal strain as an independent predictor of mortality.4 In our single-center experience, RV dysfunction in patients with COVID-19 supported with conventionally cannulated venovenous ECMO was common.
It is our belief that certain characteristics predispose patients with COVID-19 supported with ECMO to RV dysfunction. Of these factors, some may be iatrogenic in our zeal to avoid severe hypoxemia, while others are inherent to the disease process and patient characteristics.
Hyperactive delirium experienced by these patients is notoriously difficult to treat. The resultant use of sedatives may possess negative inotropic effects. Additionally, patient agitation also results in sympathetic surge, causing an increase in shunt fraction (ECMO flow:native flow), which in turn worsens hypoxemia and increases pulmonary vascular resistance. A common remedy for this phenomenon is the use of β-blockade to decrease cardiac output, which may further depress an already strained RV. Furthermore, patients with COVID-19 typically require longer runs of extracorporeal ECMO therapy, often with higher flows, potentially resulting in chronically elevated right-sided preload. Finally, obesity has been reported as a significant comorbidity in this population by the Extracorporeal Life Support Organization COVID-19 registry. In our experience, obesity was a major risk factor for RV dysfunction while receiving ECMO. It is likely that obesity acts synergistically with already altered respiratory mechanics by further promoting atelectasis, barotrauma, and pulmonary hypertension. Moreover, obesity has been found to have a direct effect on RV size, mass, and function in the general population.5
A myriad of factors may contribute to RV dysfunction in patients with COVID-19, and these effects can be exacerbated by interventions introduced during venovenous ECMO. Using a dual-stage right atrium–to–pulmonary artery cannula takes the RV out of the equation, potentially contributing to the decreased mortality reported by the authors.1 We await further details of their experience with great excitement.
Corresponding Author: Rafal Kopanczyk, DO, Clinical Division of Critical Care, Department of Anesthesiology, The Ohio State University Wexner Medical Center, 515 Doan Hall, 410 W 10th Ave, Columbus, OH 43210 (email@example.com).
Published Online: January 27, 2021. doi:10.1001/jamasurg.2020.6634
Conflict of Interest Disclosures: None reported.
Identify all potential conflicts of interest that might be relevant to your comment.
Conflicts of interest comprise financial interests, activities, and relationships within the past 3 years including but not limited to employment, affiliation, grants or funding, consultancies, honoraria or payment, speaker's bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued.
Err on the side of full disclosure.
If you have no conflicts of interest, check "No potential conflicts of interest" in the box below. The information will be posted with your response.
Not all submitted comments are published. Please see our commenting policy for details.
Kopanczyk R, Al-Qudsi OH, Bhatt AM. Extracorporeal Membrane Oxygenation and Coronavirus Disease 2019. JAMA Surg. 2021;156(4):401–402. doi:10.1001/jamasurg.2020.6634
Coronavirus Resource Center