All About ECMO in the ED

By Chris Christiansen

Case Summary:

AJ, a 72-year-old Caucasian female with a history of hypertension, hyperlipidemia, and recent mitral valve replacement due to severe stenosis, experienced a sudden loss of consciousness and pulselessness in the outpatient recovery setting. CPR was initiated by critical care staff and she was transported to JHH ED.

Physical exam: Upon arrival to the ED the patient was intubated, LUCAS 3 device was secured and in place, delivering active chest compressions, PEA via Zollinger pads/monitor, absent carotid and femoral pulses with CPR cessation. An interosseous line was placed in the right humerus prior to arrival.

ED Course:

Laboratory data:

Prior laboratory work (CBC, CMP) postoperatively was unremarkable

Imaging:

FAST - Negative fast without signs of spontaneous cardiac activity

Diagnosis: Cardiac arrest with PEA

Management:

Five rounds of Epinephrine
The ECMO team was consulted – and evaluated the patient in the trauma bay
ECMO was ultimately aborted due to new physical exam findings of a fixed and dilated right pupil by respiratory therapy
Continued pulse checks revealed absent pulses and continued to show PEA, the time of death was called, and the patient expired

Clinical Question: What are the current indications/guidelines for ECMO use in the ED, and is there room for expansion?

ECMO History:

Extracorporeal membrane oxygenation (ECMO) was invented in the 1960s by Dr. Robert Bartlett to provide prolonged cardiopulmonary support in severe acute respiratory or cardiac failure, with promising results in reducing mortality for conditions such as acute respiratory distress syndrome (ARDS), refractory cardiogenic shock, severe diffuse alveolar hemorrhage, or cardiac arrest [5]. A study comparing mortality rates showed out-of-hospital cardiac arrest, global survival rates are 2-11%. In contrast, between 1990 and 2012, the Extracorporeal Life Support Organization (ELSO) reported survival rates of 27% when ECPR was initiated [9].

Summary of Evidence:

ECMO can be divided into two primary categories: Veno-venous (VV) ECMO and veno-arterial (VA) ECMO. VV ECMO is utilized with significant isolated lung injury. VV ECMO provides respiratory support but not circulatory support. Thus, this modality should be considered in patients suffering from respiratory failure with adequate cardiac function. VA ECMO is used in cardiac or cardiopulmonary failure patients and provides circulatory and respiratory support. [2]

Figure 1: ECMO VA vs VV [13]

The use of VA-ECMO has increased 23-fold from 0.1% in 2002 to 3% in 2018. Despite being invented in the 1960s, ECMO is still relatively new in emergency departments, with 65% of ED programs being less than five years old.

A health records review showing the potential impact of ECMO in the ED by comparing “liberal” vs. “restrictive” criteria defined below in Figure 2 from McDonald et al [10].

Figure 2: ECPR eligibility criteria.

*Favorable pre-morbid status was defined as an absence of significant pre-arrest morbidities, including severe chronic obstructive pulmonary disease (CD), severe heart disease, dependency, life expectancy < 1 year, and terminal cancer. Note: Reported percentages reference the proportion of refractory out-of-hospital cardiac arrest that would have been ECPR-eligible by these criteria. CA, cardiac arrest; VT/VF, ventricular tachycardia/ ventricular fibrillation.

Based on findings from a study reviewing health records it was found that between 6-40%% of pre-hospital cardiac arrest patients would be candidates for ECMO with variability depending on the strictness of criteria. Another study estimated around 10% of outpatient cardiac arrests would likely be candidates for ECMO [12]. This would indicate around 35,000 cardiac arrest patients would be eligible for ECMO annually in the USA. Current ECMO use is estimated to be between 0.7 and 1% for this patient population. This shows an area for increased ECMO utilization in the ED and the potential for expansion of ECMO criteria [12]. There are likely many significant barriers to optimizing ECMO use such as lack of resources, training, familiarity, as well as exclusion criteria.

Recommendations:

Based on Extracorporeal Life Support Organization (ELSO) guidelines, candidates for ECMO should be younger, healthier patients with a reversible insult causing rapid cardiopulmonary collapse. ECMO should only be considered as a bridge to more definitive therapy. Specific examples provided by ELSO and JHH include [4,11] :

Massive pulmonary embolism
Myocardial infarction causing V-Tach/V-Fib or cardiogenic shock
Acute myocarditis or cardiomyopathy causing cardiogenic shock
Drowning or Hypothermia
Drug overdose causing cardiovascular collapse (such as beta-blocker or Ca-channel blocker)
Massive smoke inhalation, pulmonary contusion, or pulmonary hemorrhage
Patient has a contraindication to being placed on Lucas Device
Morbid Obesity > 40 BMI
End-tidal CO2 <10

While guidelines do exist there is room for additional research and expansion of current inclusion/exclusion criteria. Understanding the criteria will enable providers to consider ECMO use on appropriate patients. After performing this literature review it appears there is ambiguity regarding ECMO criteria. This ambiguity allows for some autonomy by the ED physician/ECMO teams to consider use on patients that may not perfectly “fit” the inclusive/exclusion criteria. As continued ECMO research is performed, guidelines are expanded, and ED physicians become more familiar with ECMO, utilization will increase in the outpatient and emergency department settings, providing improved outcomes for critically ill patients [8,12].

References:

Mosier, Jarrod M., et al. "Extracorporeal Membrane Oxygenation (ECMO) for Critically Ill Adults in the Emergency Department: History, Current Applications, and Future Directions." Critical Care, BioMed Central, 17 Dec. 2015, ccforum.biomedcentral.com/articles/10.1186/s13054-015-1155-7.
Squiers JJ, Lima B, Dimaio JM. Contemporary extracorporeal membrane oxygenation therapy in adults: Fundamental principles and systematic review of the evidence. J Thorac Cardiovasc Surg. 2016;152(1):20-32.
Ray, K. (2019, April 23). ECMO initiation in the ED. NUEM Blog. https://www.nuemblog.com/blog/ecmo
Extracorporeal Life Support Organization (ELSO). (2017). ELSO General Guidelines.
Northwestern Medicine. (n.d.). History of ECMO. https://www.nm.org/conditions-and-care-areas/pulmonary/extracorporeal-membrane-oxygenation-program/history-of-ecmo.
Right ventricular dysfunction Cara Holton, Sanket Shah et al.. https://scholarlyexchange.childrensmercy.org/research_month2023/3/
Bellezzo JM, Shinar Z, Davis DP, et al. Emergency physician-initiated extracorporeal cardiopulmonary resuscitation. Resuscitation. 2012;83(8):966-970.
Yannopoulos D, Bartos JA, Martin C, et al. Minnesota Resuscitation Consortium's advanced perfusion and reperfusion cardiac life support strategy for out-of-hospital refractory ventricular fibrillation.
Berdowski J, Berg RA, Tijssen JG, Koster RW. Global incidences of out-of-hospital cardiac arrest and survival rates: Systematic review of 67 prospective studies. Resuscitation. 2010;81(11):1479-1487.
McDonald, L., Mastoras, G., Hickey, M., McDonald, B., & Kwok, E. S. (2020). Evaluating the potential impact of an emergency department extracorporeal resuscitation (ECPR) program: a health records review. Canadian Journal of Emergency Medicine, 22(3), 375–378. https://doi.org/10.1017/cem.2019.472
Swedien, D., Mann, E., Peterson, S., Saheed, M., Jalbout, N., Carr, C., & Margolis, A. (n.d.). ECMO Cannulation for Refractory Vfib/VT Arrest (eCPR). Johns Hopkins Medicine.
Grunau B, Scheuermeyer FX, Stub D, et al. Potential

candidates for a structured Canadian ECPR program for out-of-hospital cardiac arrest.

Kelly, G., & Ihle, J. (n.d.). What is ECMO? Doctors are shocked so many ICU patients are on this advanced life support right now. The Conversation. https://theconversation.com/what-is-ecmo-doctors-are-shocked-so-many-icu-patients-are-on-this-advanced-life-support-right-now-171490