Early recognition of cardiac arrest, early effective CPR and early defibrillation are the most effective treatments yielding favorable neurological outcome from out-of-hospital cardiac arrest (OHCA). If CPR is started prior to the arrival of EMS, the patient’s chances for survival dramatically increase.
The data supporting this axiom is extensive but is exemplified by a recent large review. CPR provided by bystanders prior to EMS arrival was studied in a retrospective Swedish cohort of over 31,000 patients spanning a period from 1990–2011, and researchers found that 30-day survival improved from 4% to 10.9%.1
Bystander CPR dramatically improves a number of important OHCA benchmarks for survival. In the United States, current cardiac arrest registry data is readily available through sites participating in the Cardiac Arrest Registry to Enhance Survival (CARES).
The 2017 CARES Annual Report includes 76,215 worked OHCAs from 1,156 participating U.S. sites and 1,304 participating hospitals providing information on events from dispatch to hospital discharge with outcomes. Further review provides a current view into the outcomes associated with CPR provided prior to EMS arrival compared to first responder or EMS-initiated CPR. When one looks at benchmarks of potential resuscitation success of v fib or other shockable rhythms, including sustained return of spontaneous circulation, survival to admission and survival to discharge all strongly favor the provision of bystander CPR (64% vs. 49%; 63% vs. 47%; 49% vs. 28%, respectively).2
The time to first CPR has repeatedly been shown to be critical to outcome in studies since the 1980s. In King County, Wash., researchers examined the outcome in 244 witnessed arrests related to the times to beginning CPR and to initial defibrillation; mortality increased 3% each minute until CPR was begun and 4% per minute until the first shock was delivered.3
The outsized value of early recognition, early CPR and early defibrillation was powerfully displayed in a recent study of epinephrine.4 This emphasizes the importance of these interventions in terms of numbers needed to treat.
The period from the time of dispatch until a first responder is at the patient’s side is subject to many variables, but most EMS systems try to engineer a 6–8 minute response time with a reliability of 90%. The six-minute number likely derives from consideration of the interval of possible survival from OHCA without CPR and trying to have responders arrive in that critical interval. Further build out of EMS to provide faster response to OHCA, a very small part of the overall call volume of EMS systems, isn’t feasible or desirable.
In spring 2014, the Anchorage Fire Department changed its entire dispatch method to a system called Criteria-Based Dispatch from King County, Wash. Despite well-trained dispatchers who adhered to the protocol, meeting the time goals was hampered by the old dispatch method. Among the new changes was a simplified method for interrogating the caller to rapidly receive the answers to two key questions following confirmation of the caller and address. This includes asking the caller, “Is the person awake and alert?” and, “Is (s)he breathing normally?” If the answers to both are “no,” the dispatcher directs the caller to begin CPR. In other words, “No-No: Go to CPR.” This method has provided significantly improved results for this system. Anchorage’s bystander CPR rate also improved with this change. (See Table 1.)
Telecommunicator CPR (aka dispatcher-assisted CPR and TCPR) has been shown to be an effective intervention when studied in the U.S.5,6 and in other countries.7–9 There are opportunities for improving public access dispatch recognition of CPR and time from 9-1-1 call to first compression. There’s extensive supporting research, but perhaps the most powerful is the National Academy of Science’s Strategies to Improve Cardiac Arrest Survival, A Time to Act, in which the second major recommendation was, “Enhance EMS System Performance with an Emphasis on Dispatcher-Assisted CPR and High-Performance CPR.” The recommendations from this should be incorporated as the fundamental basis for any recommendations on state-of-the art cardiac resuscitation:10
- Telecommunicator CPR is a mandatory function of public safety dispatch centers;
- CPR be delivered as “hands-only”;
- Adopt uniform standard as minimum requirement (e.g., NHTSA curriculum);
- Dispatchers should be confirmed as proficient in recognizing OHCA, including agonal breathing, barriers to providing CPR at a distance and how to overcome, familiarity with the use and direction of the use of various AEDs;
- Quality improvement loop as mandatory component that includes time to recognition, time to first compression, encouragement for use of AED, effectiveness of coaching, use of audible metronome, among othersl;
- A fundamental recognition of the importance of telecommunicators in the chain of survival, treating them as “first-first-responders,” that includes feedback and public acknowledgement of “saves” in which they were involved; and
- Consideration of incorporation of technologies that enhance recognition and treatment including crowd-sourcing approaches, dispatch-awareness of AED locations in the community, etc.
Systems should focus on achieving excellence in TCPR, with careful attention to the metrics of the time from the caller activating 9-1-1 to dispatcher recognition of cardiac arrest and the time to first bystander compression. Telecommunicator performance should be reviewed in a timely fashion in a non-punitive manner, preferably with the dispatch/call-taker team to emphasize success and look for opportunities for improvement.
It’s also important to try to provide feedback to the team on the outcomes from the field and hospital. In those situations where a survivor can be introduced to the telecommunicator who initiated the process for his or her survival, the effects are extremely gratifying and can energize an entire dispatch agency.
It should be noted that many dispatch centers across the country have limited resources, are cash-strapped and task saturated. Call-taking and dispatch are often done by the same individual. Provision of TCPR optimally involves the telecommunicator to stay on the phone and to continue encouraging and coaching the rescuer, which could take 10 or 20 minutes or more.
A potential solution to this would be to have regional or national TCPR referral centers. Call transfer could occur very easily using current technologies to a telecommunicator with extensive experience in this technique, much like nurse advice lines. This would allow for even very small and rural agencies to provide the highest quality TCPR while continuing their baseline duties.
The future of TCPR shouldn’t be limited to our current model. The most common place for a cardiac arrest to occur is in a private residence, with 69.9% of events occurring in a home.
Patients with bystander-witnessed OHCA have three times higher likelihood of survival vs. unwitnessed events (16.0% vs. 4.6%, respectively; p < 0.0001). Initial rhythm is another major determinant of outcome and only 18.4% of victims were found in v fib overall, but it was a much higher proportion in witnessed vs. unwitnessed arrest (30.1% vs. 10.0%, respectively, p < 0.0001).2
As we look for ways to improve outcomes, we have to consider earlier detection, better provision of CPR prior to EMS arrival and ways to provide very early defibrillation.
Immediate care for victims of cardiac arrest can be provided by willing members of the community who can be notified when they’re in physical proximity to the OHCA. A significant increase in bystander CPR was demonstrated in Sweden, when volunteers were notified of a cardiac arrest in their vicinity. The provision of bystander CPR increased from an already respectable 48% to 62%, a significant 14% difference (CI 6–21; p < 0.001).11
There are growing numbers of communities employing crowdsourcing apps to alert lay rescuers of a cardiac arrest in their vicinity, as well as the locations of the nearest AEDs. An example in the U.S. is PulsePoint, and there are numerous other examples across the globe, including the Singapore Civilian Defense Force app, to name just one.
Demonstrations in the U.S. are underway to vet a subset of users as “trusted” and allow them to respond to residences to initiate care. This, coupled with geolocation of nearby AEDs, could completely change the odds of survival for a significant subset of cardiac arrests.
Fundamental enhancements to the public safety communication network may allow new opportunities for leveraging TCPR. FirstNet is an independent authority within the U.S. Department of Commerce authorized by Congress in 2012 to develop, build and operate a nationwide, broadband network that equips first responders to save lives and protect U.S. communities. The presence of a dedicated, reliable, high-bandwidth communication channel, along with applications and technologies purposely built to augment public safety activities, may herald a new era.
Currently, at least one application exists that provides the potential for video conferencing between a rescuer and the telecommunicator at dispatch. FirstNet would allow one-push access to dispatch that automatically confirms the user and location foregoing the current 1–2 minutes spent, with videoconferencing to confirm the scene and provide immediate feedback to the caller.
Failure to recognize cardiac arrest in the home is a major problem. The latest Apple Watch can use its accelerometer to detect a likely collapse. The device is also able to detect and record heartbeats, so the ability for a wearable device to detect sudden cardiac arrest is already on the market. It’s not at all inconceivable that there are ways to filter this information and make it available to loved ones, caregivers and even dispatch centers to act preemptively to speed care.
In summary, we look forward to the benefits our communities will reap as we implement a host of state-of-the-art techniques for resuscitation. Public safety access points should be optimized to provide maximal benefit to the communities they serve. In many cases, they’re an untapped, underutilized multiplier of potential for successful resuscitation from sudden cardiac death.
1. Hasselqvist-Ax I, Riva G, Herlitz J, et al. Early cardiopulmonary resuscitation in out-of-hospital cardiac arrest. N Engl J Med. 2015;372(24):2307–2315.
2. 2017 Annual Report. (2017.) Cardiac Arrest Registry to Enhance Survival. Retrieved Jan 23, 2019, from www.mycares.net/sitepages/uploads/2018/2017flipbook/index.html.
3. Weaver WD, Cobb LA, Hallstrom AP, et al. Considerations for improving survival from out-of-hospital cardiac arrest. Ann Emerg Med. 1986;15(10):1181–1186.
4. Perkins GD, Ji C, Deakin CD, et al. A randomized trial of epinephrine in out-of-hospital cardiac arrest. N Engl J Med. 2018;379(8):711–721.
5. Eisenberg MS, Hallstrom AP, Carter WB, et al. Emergency CPR instruction via telephone. Am J Public Health. 1985;75(1):47–50.
6. Lewis M, Stubbs BA, Eisenberg MS. Dispatcher-assisted cardiopulmonary resuscitation: Time to identify cardiac arrest and deliver chest compression instructions. Circulation. 2013;128(14):1522–1530.
7. Song KJ, Shin SD, Park CB, et al. Dispatcher-assisted bystander cardiopulmonary resuscitation in a metropolitan city: A before-after population-based study. Resuscitation. 2014;85(1):34–41.
8. Tanaka Y, Taniguchi J, Wato Y, et al. The continuous quality improvement project for telephone-assisted instruction of cardiopulmonary resuscitation increased the incidence of bystander CPR and improved the outcomes of out-of-hospital cardiac arrests. Resuscitation 2012;83(10):1235–1241.
9. NG YY, Leong SHB, Ong MEH. The role of dispatch in resuscitation. Singapore Med J. 2017;58(7):449–452.
10. Institute of Medicine. (June 30, 2015.) Strategies to improve cardiac arrest survival: A time to act. Retrieved Oct. 1, 2015, from http://iom.nationalacademies.org/Reports/2015/Strategies-to-Improve-Cardiac-Arrest-Survival.aspx.
11. Ringh M, Rosenqvist M, Hollenberg J, et al. Mobile-phone dispatch of laypersons for CPR in out-of-hospital cardiac arrest. N Engl J Med. 2015;372(24):2316–2325.