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The American Heart Association (AHA) estimates 295,000 out-of-hospital cardiac arrests each year. About 3%–8% of these patients will survive to discharge. The most influential variable for survival is the time interval from cardiovascular collapse until defibrillation. The chance of survival from a witnessed ventricular fibrillation event declines by 7%–10% for every minute that CPR is not provided. Thus, adequate training in Advanced Cardiac Life Support (ACLS) is imperative. This may be more important in the out-of-hospital setting where only one provider may be present as opposed to the hospital setting where a team of providers can simultaneously perform chest compressions, defibrillation, and airway management.


Initial Evaluation

Once the patient is found unresponsive, the patient’s chest should be scanned for 5–10 seconds to evaluate for breathing. If the patient is not breathing, an automatic external defibrillator (AED) should be made available. The carotid pulse should be checked for 5–10 seconds. If no pulse is detected, chest compressions should be initiated.

Traditionally, ACLS providers were guided by the sequence of A–B–C (Airway, Breath, Circulation). However, as noted above, the most important barrier to survival is the time to onset of chest compressions. If the A–B–C sequence is followed, valuable time can be lost in order to achieve adequate ventilation. Thus, the 2010 AHA guidelines recommended changing the sequence to C–A–B for both adult and pediatric basic life support.

Chest Compressions

After it is determined that a pulse is not palpable, chest compressions should be performed for 2 minutes. Proper quality of chest compressions is vital to proper circulation during a cardiac arrest. Chest compressions are inadequate if end-tidal CO2 is less 10 mmHg or diastolic blood pressure is less than 20 mmHg. Prior guidelines recommended a compression depth of 1.5–2 inches at a rate of approximately 100 times per minute. The 2010 AHA guidelines now recommend a depth of at least 2 inches at the same frequency (a pattern associated with higher survival rates). In addition, there should be complete recoil of the chest between compressions. After 2 minutes of chest compressions, a pulse check should be performed for a maximum of 10 seconds. If a defibrillator is present and a shockable rhythm is identified, defibrillation should occur. If a nonshockable rhythm is identified at any point, CPR should be continued.

According to the AHA, 383,000 out-of-hospital cardiac arrests occur annually and 88% occur at home. Unfortunately, 70% of Americans are not comfortable administering CPR. In the past, it was recommended that bystanders perform chest compressions and ventilation. However, since most adults do not receive bystander CPR due to lack of bystander comfort, the recommendations have been simplified. The 2010 AHA guidelines recommend that untrained bystanders perform only compressions until other responders arrive at the scene. Once a trained responder arrives, ventilation ...

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