Since its inception in the 1960s, traditional CPR has been heralded as a revolutionary life-saving technique. However, the limitations of CPR are becoming increasingly apparent, particularly in cases of out-of-hospital cardiac arrest (OHCA). Currently, the survival rate for OHCA patients with good neurological function at discharge stands at a mere 7.5 percent. This raises important questions about the efficacy of traditional CPR and the need for more effective interventions.
Limitations of traditional CPR
For CPR to be effective, the steps in the chain of survival must be meticulously followed in sequence; however, any disruption or delay in these steps can significantly weaken the chain, leading to decreased survival rates or poor neurological outcomes. Key challenges to successful CPR include:
- Delayed recognition of cardiac arrest and initiation of CPR
- Lack of widespread bystander CPR (only 1 in 3 OHCA victims receive it)
- Time-sensitive nature of CPR (effectiveness decreases rapidly after 5 minutes)
- Limited availability and effectiveness of early defibrillation
- Minimal impact of Advanced Cardiovascular Life Support (ACLS) interventions on overall survival rates
While there have been fluctuations and regional improvements in survival, the overall global survival rate to hospital discharge for OHCA patients who receive CPR has shown only a moderate increase. Globally, the overall survival rate for OHCA patients, regardless of neurological outcomes, was 8.6 percent from 1976 to 1999, only increasing to 9.9 percent from 2010 to 2019. Despite some progress over the decades, the increase has not been steady or significant.
Changing the paradigm with ECPR
Although traditional CPR has its place, its limited effectiveness in cases of OHCA highlights a critical issue: The primary focus has been on restarting the heart rather than ensuring adequate oxygen supply to the brain. The saying used to be, “Hearts too young to die,” but the reality is that in most cardiac arrest cases, it is not the heart that determines survival—it is the brain. In the majority of cases, the heart does come back, but if the brain has suffered extensive oxygen deprivation, the chances of a good neurological outcome are slim. For those whose hearts do not recover, advanced interventions like left ventricular assist devices (LVADs) and heart transplants offer potential solutions—the brain, however, doesn’t have similar options.
Extracorporeal cardiopulmonary resuscitation (ECPR) emerges as a natural solution to these limitations. Unlike traditional CPR, which primarily focuses on mechanical chest compressions and defibrillation, ECPR uses extracorporeal membrane oxygenation (ECMO) to ensure continuous oxygenated blood flow to the brain and other vital organs during resuscitation. This advanced life support technique not only maintains critical organ function but also provides a crucial window for medical professionals to diagnose and treat the underlying cause of cardiac arrest, such as a heart attack or other cardiovascular issues.
ECPR essentially buys time to identify and correct the root problem that caused the heart to stop in the first place. It also ensures that the brain and vital organs are protected from ischemic damage during this period, significantly increasing the chances of survival and recovery with good neurological outcomes. By addressing the immediate need for oxygenated blood flow and providing time to address the underlying cause of cardiac arrest, ECPR represents a comprehensive approach to resuscitation that traditional CPR alone cannot match.
In comparing CPR and ECPR outcomes, the stark differences become clear. The survival rate for OHCA patients with good neurological function at discharge stands at a mere 7.5 percent, but data show that 30 percent of all ECPR patients survive neurologically intact. This is more than a tripling of the standard OHCA survival rate. Annually, an estimated 350,000 OHCAs occur in the United States, and at present, only about 30,000 of these individuals survive to discharge. If ECPR were more broadly applied, it has the potential to save tens of thousands of lives each year.
Yet, despite the promising potential of ECPR, its utilization remains limited. Per the Extracorporeal Life Support Organization (ELSO), about 1,700 patients received ECPR in North America in 2023. However, estimates suggest that up to 43,000 more patients could be eligible for ECPR each year in the US alone. Currently, ECPR is primarily offered in specialized centers with the necessary equipment and trained personnel, often found in urban and well-funded hospital systems. This leaves many rural and underserved areas without access to this potentially life-saving treatment.
Key barriers and solutions to expand access to ECPR
Fifteen years ago, ECPR was in its infancy, with many skeptics and scattered data supporting its use. However, ECPR is no longer a fringe treatment that is debated for its efficacy. In March 2024, ECPR became a Level 2a indication in the AHA guidelines for the treatment of refractory ventricular tachycardia (V-Tach) and ventricular fibrillation (V-Fib), ranking it higher than the medication amiodarone, which has been the standard offering for this population after failed defibrillation attempts. This recognition is a significant milestone, finally acknowledging the potential of ECPR and its critical role in improving cardiac arrest outcomes.
To fully realize the benefits of ECPR, several key barriers need to be addressed:
Overcoming misconceptions and myths
The first hurdle relates to misconceptions about the efficacy of ECPR and/or ECMO. However, these myths are gradually being debunked thanks to increasing research, refined techniques, and vocal advocacy within the medical community about improved survival rates. This growing body of evidence is helping to shift perceptions and highlight the promise and potential of these advanced resuscitation methods.
Shifting focus from survival rates to absolute numbers
The focus on maintaining a high survival rate percentage for ECPR should be shifted. We do not account for how many cardiac arrest patients die after intubation, so we should similarly not place undue emphasis on the survival rate for ECPR. The emphasis should be on the absolute number of survivors rather than the survival rate percentage. By concentrating on achieving a 30 percent survival rate, we might be missing the opportunity to save a larger number of patients. The goal should be maximizing the total number of lives saved, not just achieving a specific statistical target.
Expanding inclusion criteria
One crucial step is to simplify the inclusion criteria for ECPR. This will broaden its acceptance and application, reducing the hesitance of physicians to perform the procedure due to fear of critique. By adhering to these basic criteria, the procedure’s application can be more widespread, even though the overall survival rate might be lower. The emphasis remains on increasing the total number of lives saved.
Simplifying ECPR for broader accessibility
To make ECPR widely accessible, its complexity must be reduced. Just as intubation and chest tube insertion evolved from specialist procedures to standard practice for many health care providers, ECPR can follow a similar path of simplification and broader adoption.
This same approach can be applied to ECPR by focusing on several key areas to streamline the process. First, creating a simplified ECMO starter pack that only includes the essential items needed for the procedure will ensure ease of use and quick deployment. Second, simplifying the cannulation process by using smaller cannulae can make the procedure more accessible, especially for those who do not perform it frequently. Finally, by creating a simplified ECMO console that features a basic design with just a pump, oxygenator, and flow rate control knob, ECPR can be made more user-friendly and effective.
The cure for the common code
ECPR significantly increases survival rates for OHCA patients. Although barriers still exist to its widespread implementation, a comprehensive training program that addresses patient selection, simplified cannulation, and streamlined commencement can make a substantial difference. We truly have a cure for the common code, but it is up to the medical community to embrace and implement these changes. By doing so, we can move the needle from a stagnant 7.5 percent survival rate to potentially saving tens of thousands more lives each year.
Jon Marinaro is a critical care physician.
