Pulmonary Physiologic Assessment of Patients on Veno-arterial Extracorporeal Membrane Oxygenation (VA ECMO)

Study Overview
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Brief Summary
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There is limited data on the respiratory system mechanics and ideal mode of ventilation for patients on veno-arterial extra-corporeal membrane oxygenation (VA ECMO) post cardiac arrest. In this observational study, the investigators will review and/or obtain laboratory, hemodynamic, respiratory system mechanical, and clinical data from patients on VA ECMO. The specific aims of this study are as follows: Aim 1: To characterize the lung ventilation strategy employed in patients on VA ECMO and its success. Aim 2: To characterize respiratory system mechanics while on ECMO using esophageal manometry and Electrical Impedance Tomography (EIT). Aim 3: To characterize right heart function and pulmonary vascular hemodynamics on the employed ventilation strategy. The overarching hypothesis is that fine-tuned individualized ventilation might be superior to an algorithm that does not account for cardiac and pulmonary functions. Therefore, the aims of this study are to identify areas in which the ventilation strategy may theoretically be suboptimal, which will guide future interventional studies investigating alternatives methods of ventilation which may reduce time on the ventilator after cardiac arrest, time in the intensive care unit, and need for veno-venous ECMO.

Official Title
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Pulmonary Physiologic Assessment of Patients on Veno-arterial Extracorporeal Membrane Oxygenation (VA ECMO)

Conditions
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Cardiac Arrest, Pulmonary Injury

Intervention / Treatment
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* Procedure: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO)
* Device: Electrical Impedance Tomography (EIT)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: On VA ECMO after cardiac arrest Between 18 and 85 years of age Has an orogastric or nasogastric tube with esophageal balloon capabilities in place Exclusion Criteria: Known pre-existing significant pulmonary pathology Pacemaker or implanted cardiac defibrillator

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO)|VA-ECMO used for resuscitation after cardiac arrest|
|Device: Electrical Impedance Tomography (EIT)|EIT used to demonstrate ventilation and perfusion distribution in intubated patients on VA-ECMO|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percent of total distribution of ventilation by region, on given ventilator settings | EIT will be used to determine the percent of total ventilation occurring in each of four lung quadrants on an axial plane: right upper, left upper, right lower, and left lower. | Within 24-48 hours of ECMO cannulation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time on VA-ECMO |  | 14 days, 90 days | 
| Need to transition to VV-ECMO |  | 14 days, 90 days | 
| Time on mechanical ventilation |  | 14 days, 90 days | 
| Time in ICU |  | 14 days, 90 days | 
| 90-day mortality |  | 90 days | 
| Incidence of ventilator-associated pneumonia |  | 14 days, 90 days |