Specific guidelines for the teaching and practice of CPR are published periodically (see Fig 58-1: Simplified adult basic life support (BLS) algorithm through Fig 58-4: Adult tachycardia (with pulse) algorithm). The two levels of CPR care are referred to as BLS for ventilation and chest compressions without additional equipment and ACLS for using all modalities available for resuscitation. Medical personnel need to be well versed in both levels of care.

1. Cardiocerebral Resuscitation. An approach to victims of sudden cardiac death has been called cardiocerebral resuscitation or minimally interrupted cardiac resuscitation.
   1. Time-Sensitive Model of Ventricular Fibrillation. Untreated ventricular fibrillation has been described as a time-sensitive model consisting of the electrical (first 4–5 minutes), hemodynamic (next 10–15 minutes when perfusing the brain and heart with oxygenated blood is critical), and metabolic (not clear what intervention will be successful) phases.
      1. Prompt defibrillation during the electrical phase is when CPR has had the most dramatic effect and why public access AED has proven beneficial. The longer ventricular fibrillation continues, the more difficult it is to defibrillate and the less likely successful resuscitation is.
      2. If an arrest is witnessed and a defibrillator or AED is immediately available, then defibrillation should be the first priority in resuscitation.
   2. The most important intervention during the hemodynamic phase of cardiac arrest is producing coronary perfusion with chest compressions before any attempt to defibrillate.
   3. In the absence of prompt defibrillation, the most important intervention for neurologically normal survival from cardiac arrest is restoration and maintenance of cerebral and myocardial blood flow. This is the main principle behind the concept of cardiocerebral resuscitation.
2. Bystander Cardiopulmonary Resuscitation. Restoration of cerebral and myocardial blood flow must begin at the scene of the cardiac arrest. Much of the reluctance to initiate CPR as a bystander is the concern of applying mouth-to-mouth ventilation on a stranger.
   1. If the airway remains patent during CPR, chest compressions cause substantial air exchange. Some data suggest that eliminating mouth-to-mouth ventilation early in the resuscitation of witnessed fibrillatory cardiac arrest is not detrimental to outcome and may improve survival.
   2. Recognizing the deleterious effects of prolonged pauses in chest compressions for ventilation, the 2005 AHA guidelines change the compression-to-ventilation ratio from 15:2 to 30:2, recommending that ventilation be done in 2 to 4 seconds.
   3. A public education program stresses an immediate call to 911 and prompt institution of continuous chest compressions without ventilation in the case of witnessed unexpected sudden collapse in adults.
3. Cardiocerebral Resuscitation During Advanced Life Support
   1. The principle of not interrupting chest compressions to maintain cerebral and myocardial perfusion applies to resuscitation attempts by health care providers as well as lay bystanders.
   2. The adverse hemodynamic consequences of interrupting chest compressions have been well documented. Blood flow stops almost immediately with cessation of chest compressions and returns slowly when they are resumed. Consequently, in cardiocerebral resuscitation, the emphasis is that chest compressions are to be paused only when absolutely necessary and then for the shortest time possible.
   3. Positive-pressure ventilation increases intrathoracic pressure, reducing venous return, cardiac output, and coronary perfusion pressure and adversely affecting survival.
4. Rhythm Analysis and Defibrillation
   1. Defibrillation during the hemodynamic phase is counterproductive, usually producing either asystole or pulseless electrical activity.
   2. The success rate of a single shock is between 70% and 85%, with most monophasic waveform defibrillators and more than 90% with the newer biphasic waveform units.
   3. In prolonged ventricular fibrillation, successful defibrillation almost always results in asystole or pulseless electrical activity. Immediately restarting chest compressions (without waiting to check a pulse or reanalyze the ECG rhythm) after defibrillation to provide coronary perfusion nearly always results in reversion to a perfusing rhythm.

Cardiopulmonary Resuscitation

1. History
2. Scope of the Problem
3. Ethical Issues: Do Not Resuscitate Orders in the Operating Room
4. Components of Resuscitation
5. Pharmacologic Therapy
6. Electrical Therapy
7. Putting it all Together
8. Pediatric Cardiopulmonary Resuscitation
9. Postresuscitation Care