Bystander CPR: A key link in the chain of survival

The American Heart Association estimates that approximately 350,000 people in the United States experience a cardiac arrest while outside of the hospital. Unfortunately, only 12 percent of these cases will survive the cardiac event. This makes death by cardiac disease one of the top killers in the United States [1]. Significant research in cardiac resuscitation has been ongoing since the 1950s, with time, effort and money examining the multiple variables affecting survival rates.

One component of the cardiac chain of survival, bystander CPR, appears to play a major role in the increase of survival to discharge rates in cardiac arrest. It is critical that EMS agencies play their part in strengthening this part of the resuscitation strategy in order to improve community health.

Numerous studies have shown the faster the response to someone who is in sudden cardiac arrest, the better their chances for survival. A bystander’s willingness to get involved when they witness SCA - by calling 911, starting CPR, getting that first shock into the patient in under 3 minutes - all those things in the chain of survival add up to increased survival rates.

The phrase “chain of survival” was coined to describe a series of events that if strung together and performed in a timely manner, would greatly improve the chances of survival from sudden cardiac arrest in the out of hospital setting [2]. These events include:

• Early access to the emergency cardiac care system by recognizing sudden cardiac arrest quickly and calling 911
• Early CPR by those nearest to the sudden cardiac arrest, bystanders
• Early defibrillation of ventricular arrhythmias
• Early advanced level care by trained professionals

Throughout the 1990s, the focus was placed on the back end of the chain of survival through the medications and procedures being done by paramedics and emergency department staff to improve survival rates. However, by the 2000s attention turned toward the improvement of the front end of the chain, specifically how to improve the incidence of bystander-provided CPR at the moment of collapse.

It has been known that early CPR by members of the public, performed before the arrival of trained responders, improved sudden cardiac arrest survival rates. Yet the numbers of bystanders trained in CPR remains low, and range considerably from one community to the next. Rates of only 30 to 40 percent of sudden cardiac arrest receiving bystander CPR have been reported [4]. Access to CPR training has been shown to affect willingness to perform CPR in an emergency even [5]. Furthermore, southern states, especially in areas with higher proportions of Hispanic and African American populations and lower median incomes have lower rates of CPR training [6].

Why are bystander CPR rates so low?

There have been a number of theories as to why bystander CPR rates have remained historically low, including fear of cross infection, fear of liability, the complexity of traditional CPR instruction that included mouth-to-mouth breathing techniques, and ultimately a lack of confidence in performing correctly in real life situations [7].

A recent conversation with AEDSuperstore gleaned a sample step toward solving the issue of bystander CPR avoidance, “Knowing how to recognize sudden cardiac arrest - its signs and symptoms - along with more public awareness on how simple and critical hands-only CPR can be, could lead to more involvement. A public service campaign like the one done in the UK would be incredibly helpful.”

Regardless of the cause, it is essential to increase the percentage of sudden cardiac arrest patients who receive prearrival CPR, as a cost effective and efficacious method to improve survival to discharge rates.

Expanding CPR training opportunities

Up until the late 2000s, CPR courses taught to bystanders took several hours to complete, were costly and resource intensive, creating a barrier to readily accessible training opportunities. With the 2010 American Heart Association guideline recommendation that compressions-only CPR training may be more effective in training bystanders, organizations around the nation made an effort to train large numbers of bystanders in this technique. Without the extra burden of having to teach manual ventilation techniques and focusing on high-quality chest compressions practice, the time frame for training shortened considerably. Research has supported that change; studies comparing compressions only CPR versus “standard CPR” by nonprofessional bystanders showed a higher survival rate for sudden cardiac arrest patients who received compression only CPR [4].

Self-instructional kits have been created by the AHA and other training organizations that allows video-driven instruction to occur any time, and in any space [8]. School district CPR programs have used these kits to train middle and high school students during class, with the intent of having the students bring the kits home and train family members. This has resulted in a large number of citizens being trained in CPR at a modest cost [9,10].

Internet-based CPR training has also drawn attention. A small study indicated that students who viewed a short CPR training video combined with a homemade mannequin that can be assembled with household items greatly improves CR skills [11].

Widespread adoption of dispatch-assisted CPR training

Despite increasing access to CPR training, it is still likely that at the temporal moment of sudden cardiac arrest, the person closest to the victim is capable of performing hands-only CPR. 911 telecommunicators can provide just in time, over-the-phone guidance for individuals who are willing to provide CPR. Studies have shown the efficacy of dispatch CPR instructions in improving sudden cardiac arrest survival rates [12].

Providing reassurance to the would-be lay rescuer

The AHA has recommended that bystanders be educated on the virtually nonexistent risk of disease transmission during CPR. Information about relevant Good Samaritan laws should be provided, and worksites and public spaces should have basic personal protective equipment such as gloves and pocket masks co-located with public access automated external defibrillators [16].

The role of EMS agencies

As the first professionally trained link in the chain of survival, EMS agencies can play a critical role in training its community members in CPR and AED use. Examples include:

• Sponsoring large-scale, one-day events such as Save-A-Life Saturday
• Training middle school health teachers how to teach compression-only CPR to their students and providing training equipment when needed [17]
• Implementing dispatch-assisted CPR protocols within the 911 call center
• Advocating for legislative changes that encourage or mandate CPR training in public schools
• Work with government officials and other stakeholders to place AEDs in public areas and locations where the likelihood of SCA is higher
• Publically recognize bystanders who make the effort to perform CPR at the temporal moment of SCA

SCA is a public health disease that responds to carefully planned interventions based on evidence. Given the growing body of evidence that shows the benefit of bystander CPR, EMS agencies can take the lead to improve their community’s ability to respond when seconds truly count.

References
1. American Heart Association. Cardiac Arrest Statistics. http://cpr.heart.org/AHAECC/CPRAndECC/General/UCM_477263_Cardiac-Arrest-Statistics.jsp retrieved 12 December 2016.
2. Yin HY et al (2016). National community chain-of-survival initiatives are associated with improved bystander cardiopulmonary resuscitation rates and survival for cardiac arrests in Taiwan. Circulation 2016; 134: A19190.
3. Ritter G et al. The effect of bystander CPR on survival of out-of-hospital cardiac arrest victims. Am Heart J. 1985 Nov;110(5):932-7.
4. Riva G et al. Increase in bystander cardiopulmonary resuscitation in Sweden during the last 15 years is mainly attributed to increased rates of chest compression only CPR. Circulation 2016; 134:A13201
5. Bray J et al. Regions with low rates of bystander CPR also have lower rates of residents with CPR training: A telephone survey of residents in Victoria, Australia. Circulation 2016:134:A16174
6. Anderson ML et al. Rates of cardiopulmonary resuscitation training in the United States. JAMA Intern Med. 2014 Feb 1;174(2):194-201.
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8. American Heart Association. CPRanytime.org website. www.cpranytime.org.
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12. Sanko S et al. Impact of a new medical dispatch system on telecommunicator-assisted CPR. Annals of Emergency Medicine 2016; 68:4.
14. Hallstrom AP, Cobb LA, Johnson E, Copass MK. Dispatcher assisted CPR: implementation and potential benefit: a 12-year study. Resuscitation. 2003;57: 123–129.
16. Abella BS et al. AHA Scientific Statement: Reducing Barriers for Implementation of Bystander-Initiated Cardiopulmonary Resuscitation. Circulation. 2008; 117: 704-709.
17. Daubs B. Local students and Save Lives Sonoma take CPR lessons to heart. The Healdsburg Tribune, 19 February 2014. http://www.sonomawest.com/the_healdsburg_tribune/news/local-students-and-save-lives-sonoma-take-cpr-lessons-to/article_572bfbd4-99ab-11e3-b327-0019bb2963f4.html retrieved 5/5/16.