TAKE-HOME POINTS


■ PAs can help to educate the public on new CPR techniques and methods that have demonstrated an efficacy in OHCA survival.

■ Rapid initiation of CPR remains the fundamental predictor of survival in patients with OHCA. The value placed on chest compressions has led to a change in clinical paradigm from the ABC sequence to the CAB sequence in order to restore cardiac perfusion as rapidly as possible in adults.

■ Limited interruption of chest compressions and rapid defibrillation improve the rate of survival to hospital discharge in patients with OHCA.

■ The ABC sequence of CPR remains the preferred method of resuscitation in the pediatric population. 

WHO SHOULD READ THIS?


This material is relevant for physician assistants who provide patient care in all settings and communities.


WHY IS THIS IMPORTANT?


Sudden cardiac death accounts for 60% of all cardiac deaths annually in the United States, with most occurring outside the hospital or health care environment. Out-of-hospital cardiac arrest (OHCA) has an incidence of 52 per 100,000 population in North America, making it the third leading cause of death.1 


Each year, more than 300,000 patients with OHCA are treated by emergency medical services (EMS), with an approximate survival rate of 6%.2 The low survival rate is partly attributable to bystander aversion to mouth-to-mouth ventilation when delivering cardiopulmonary resuscitation (CPR), fear of injuring the patient, and fear of contracting disease.3 In fact, only 30% of cardiac arrest victims receive bystander CPR prior to arrival in the emergency department.3 Bystander aversion is not limited to the lay public, as only 3% of nurses and 16% of medical students were willing to provide mouth-to-mouth ventilation.3 When performed, bystander CPR increases the odds of survival 3-fold, and early bystander CPR (performed less than 4 minutes after cardiac arrest) increases the odds of survival 4.5-fold.3 


The first CPR guidelines implemented in 1966 by the American Heart Association (AHA) resulted in thousands of lives saved through bystander intervention.4 Periodically, those guidelines have been updated and changed based on new research and technological advances. Physician assistants, as primary health care providers, should be informed of these changes, demonstrate competency in providing CPR, and be involved in community education regarding changes in CPR delivery. 


WHAT'S NEW? 


In conjunction with the International Liaison Committee on Resuscitation (ILCOR), the AHA reviews current research and suggests changes and recommendations to CPR guidelines every 5 years. The most recent revision was made in October 2010.2 
To understand the significance of the 2010 changes, it is necessary first to understand the 2005 ILCOR recommendations.


In the 2005 guidelines, the instructions for the lone bystander delivering Basic Life Support (BLS) CPR were to follow the sequence of Airway management, Breathing rescue, and Circulation enhancement (the ABCs of CPR). However, bystander participation in CPR increases when the rescue breathing component is eliminated, and when a lone bystander is performing CPR, continuous chest compression (CCC) has been demonstrated to be easier to perform and to deliver more effective compressions.3 The 2005 recommendations—30:2 compressions-to-ventilation ratio—suggested that more attention be placed on chest compressions during CPR, with very minimal interruptions for rescue breathing.4 Thus the recommendation for chest compressions increased in the 2005 recommendations from 15 to 30 per cycle, or 100 compressions per minute. 


Chest compressions address the primary causes of cardiac arrest (ventricular fibrillation, ventricular tachycardia), focus on enhanced peripheral perfusion, and deemphasize the need to establish an airway.5 A meta-analysis of CCC-CPR versus standard CPR identified a 22% improvement in rates of survival to hospital discharge in patients who received CCC-CPR.6 Within the chain of survival, it is important for the health care provider to minimize interruptions to chest compressions, subsequently decreasing the interval of CPR and the delivering of defibrillation, because a shorter interval is correlated with decreased mortality.2 


Based on the enhanced value placed on chest compressions in CPR and supported by multiple studies suggesting improved outcomes in OHCA patients who receive chest-compression-only CPR, the ILCOR, in October 2010, released its latest recommendations. This 2010 revision called for a change from the ABC (airway, breathing, and circulation) acronym of clinical practice to a new acronym: CAB (chest compressions, airway, breathing).2 This paradigm shift highlights the importance of chest compressions in CPR by initiating the sequence of CPR with chest compressions as opposed to establishing an airway, in hopes of decreasing lost time in the initiation of circulation management. 


This change, adopted by the AHA, has been recommended for both bystanders and health care providers in adult BLS CPR. The steps in the new algorithm for adult cardiac arrest are as follows: 


  1. Recognize cardiac event (victim unresponsive; not breathing or only occasional gasps)

  2. Call for assistance/notify emergency response system
  3. 
Initiate CPR using the new CAB sequence of 30 compressions per cycle

  4. Establish airway and give two breaths within the first minute

  5. Defibrillate as soon as possible

  6. Resume 30:2 compression-to-
ventilation ratio

  7. Defibrillate with as limited interruption as possible.


WHAT ELSE IS IMPORTANT TO KNOW?


Survival to hospital discharge has been associated with the rapid initiation of chest compressions in CPR,6,7 probably because rapid initiation limits interruption in cardiac perfusion.8,9 In addition, the lost time associated with the "look, listen, and feel" assessment has been replaced with notification of EMS by either the bystander or health care provider,2 and the initiation of emergency services remains a critical aspect of effective care and should occur as early as possible after a witnessed cardiac event. Greater emphasis should be placed on having bystanders or health care providers deliver effective, quality chest compressions, as studies have indicated improved OHCA survival with the initiation of continuous chest compressions.6 


Only 30% of OHCA victims are attended to by lone rescuers or bystanders because of bystander hesitancy to establish an airway and provide rescue breathing.7 The most recent recommendations may eliminate much of this hesitancy and make bystanders more willing to provide out-of-hospital CPR. Compression-only CPR is a sufficient method of resuscitation and should be encouraged in bystanders. 


DO THESE CHANGES APPLY TO CHILDREN?


No. In the pediatric population, the ABC sequence is still the sequence of choice. The most likely cause of cardiac arrest in children is respiratory, not cardiac. Thus the AHA continues to emphasize rapid initiation of chest compressions and completion of the compression-to-ventilation cycle with only minimal delay in maintenance and delivery of air.2 JAAPA

This article was written by Folusho E. Ogunfiditimi, PA-C. Contributors included the other members and staff of CSAC 2010-2011: Chair Alison C. Essary, MHPE, PA-C; Gilbert A. Boissonneault, PhD, PA-C; Anthony E. Brenneman, MPAS, PA-C; Marie-Michèle Léger, MPH, PA-C; Mark F. McKinnon, PA-C; and Thomas Moreau, PA-C, MS. The manuscript was edited by Sarah Zarbock, PA-C.

REFERENCES


1. Callaway CW, Schmicker R, Kampmeyer M, et al. Receiving hospital characteristics associated with survival after out-of-hospital cardiac arrest. Resuscitation. 2010;81(5):524-529.


2. Field JM, Hazinski MF, Sayre MR, et al. Part 1: executive summary: 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation. 2010;122(18 suppl 2):S640-S656.


3. Ramaraj R, Ewy GA. Rationale for continuous chest compression cardiopulmonary resuscitation. Heart. 2009;
95(24):1978-1982. 


4. Hazinski MF, Nolan JP, Billi JE, et al. Part 1: executive summary. 2010 international consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations. Circulation. 2010;122:S250-S275.


5. Ewy GA. Continuous-chest-compression cardiopulmonary resuscitation for cardiac arrest. Circulation. 2007;116(25):
2894-2896.


6. Hupfl M, Selig HF, Nagele P. Chest-compression-only versus standard cardiopulmonary resuscitation: a meta-analysis. Lancet. 2010;376(9752):1552-1557.


7. Iwami T, Kawamura T, Hiraide A, et al. Effectiveness of bystander-initiated cardiac-only resuscitation for patients with out-of-hospital cardiac arrest. Circulation. 2007;116(25):2900-2907.


8. Ong ME, Ng FS, Anushia P, et al. Comparison of chest compression only and standard cardiopulmonary resuscitation for out-of-hospital cardiac arrest in Singapore. Resuscitation. 2008;78(2):119-126.


9. Bohm K, Rosenqvist M, Herlitz J, et al. Survival is similar after standard treatment and chest compression only in out-of-hospital bystander cardiopulmonary resuscitation. Circulation. 2007;116(25):2908-2912.