Cardiopulmonary Arrest

Cardiopulmonary resuscitation (CPR) is intended to rescue patients with acute circulatory failure, respiratory failure, or both. The most important determinant of short-term and long-term neurologically intact survival is the interval from onset of the arrest to restoration of effective spontaneous circulatory and respiratory function. Numerous studies have shown that early defibrillation is the most important factor influencing survival and the minimization of sequelae. The sequences included here have been developed to optimize treatment. They are useful guidelines for most patients but do not preclude other measures that may be indicated for individual patients. The most crucial aspects of treatment are contained in the mnemonic CAB—chest compressions, airway maintenance, and breathing. The most recent published CPR protocols are the 2015 (updated in 2018) American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care; these basic CPR steps for adults, children, and infants can be found online at https://eccguidelines.heart.org/index.php/circulation/cpr-ecc-guidelines-2/, along with extensive resources, including text, graphics, and video demonstrations of CPR techniques.

The following are steps for CPR using CAB; they are performed with an unconscious patient (Table 16-1, Video 16-1):

1. Determine the level of responsiveness. Attempt to arouse the patient by tapping on his or her shoulder and shouting, “Are you all right?” Do not shake the head or neck until this area has been evaluated for trauma. Quickly note if breathing is absent or abnormal (eg, gasping).

2. Activate the Emergency Medical Services (EMS) system if there is no patient response (in the United States, call 911 where available). Rescuers should “phone first” for unresponsive adults and give the location and nature of the emergency.

3. Retrieve an automated external defibrillator (AED) or send someone for the AED.

4. Position the victim supine on a firm, flat surface.

5. In an unresponsive patient without respirations, initiate chest compressions. (Determination of a pulse is no longer indicated.) Place the heel of 1 hand at the midsternal region, with the bottom of the hand 1–2 finger-breadths above the xiphoid process.

6. “Push hard and push fast.” The recommended cardiac compression rate is at least 100 compressions per minute (100–120/min). The depth of chest compression is critical; optimal compression depths are 1.5 inches in infants (⅓ of body depth), 2.0 inches in children (⅓ of body depth), and at least 2.0 inches in adults. The chest must be allowed to fully recoil between compressions; therefore, leaning on the chest between compressions should be avoided.

7. Deliver 30 chest compressions.

8. As soon as the AED is available, the unit should be connected to the patient and instructions followed for assessing the heart rhythm. Interruptions to chest compressions should be minimized by having a second rescuer (eg, the person who retrieved the AED) charge and apply the AED. Resume chest compressions immediately after the shock and continue until 30 compressions are given.

   Table 16-1 Quick Reference Chart: 2015 CAB Guidelines

   

9. Open the airway. Rescue breathing (see step 10 for technique) should be performed at a rate of 10–12 ventilations per minute. Use the head-tilt, chin-lift maneuver to provide a good airway. This is done by applying firm pressure to the forehead while placing the fingers of the other hand under the chin, supporting the mandible. If a neck injury is suspected, the modified jaw thrust without head extension should be used.

10. Pinch the nose closed. Cover the patient’s mouth with yours, making a tight seal, and ventilate twice with full breaths (1 second each). A 2-second pause should be observed between breaths. Visible chest rise should be seen with each breath. Resume chest compressions immediately. The “Help” button on the AED can be pressed for guidance with both compression and rescue breathing frequency.

11. For 1-and 2-rescuer CPR: When the victim’s airway is unprotected, 30 compressions should be performed before the victim is ventilated twice. About 4 seconds should be taken for 2 ventilations, including the pause between ventilations.

12. If 2 rescuers are present, chest compression duties should be switched every 2 minutes or 5 compression/ventilation cycles.

13. Continue with compression/ventilation cycles until EMS arrives.

Courtesy of A. Luisa Di Lorenzo, MD.

Access all Section 1 videos at www.aao.org/bcscvideo_section01.

CPR is most effective when started immediately after cardiac arrest. If cardiac arrest has persisted for more than 10 minutes, CPR is unlikely to restore the patient’s central nervous system (CNS) to prearrest status. If there is any question about the exact duration of cardiac arrest, the patient should be given the benefit of the doubt and resuscitation should be started.

The risk of disease transmission through mouth-to-mouth ventilation is very low, but a variety of face shields and masks are available for the health care professional. Masks are more effective than face shields in delivering adequate ventilation. Alternative airway devices (eg, a laryngeal mask airway or a esophageal/tracheal dual lumen airway device) may also be acceptable for rescuers trained in their use.

Patients with suspected stroke should be rapidly transported to a hospital capable of initiating fibrinolytic therapy within 1 hour of arrival and within 3 hours of the onset of symptoms. These patients merit the same priorities for dispatch as patients with acute myocardial infarction or major trauma. See Chapter 6 in this volume for further discussion of stroke.

The following adjuncts are helpful in CPR and are suggested components for a medical emergency tray or crash cart:

• oxygen, to enhance tissue oxygenation and to prevent or ameliorate a hypoxic state

• airways, adult and child, oral and nasal, to be used on unconscious or sedated patients

• a barrier device, such as a face shield or mask-to-mouth unit, to prevent disease transmission. Both can be used with supplemental oxygen and are especially useful if the rescuer is inexperienced in using a standard bag-valve device, which should also be included as standard equipment to help secure the airway.

• Intravenous (IV) drugs (for use by those with ACLS training)

• IV solutions: dextrose 5% and water, D5 Ringer’s lactate, normal saline

• syringes (1, 5, and 10 mL), hypodermic needles (20, 22, and 25 gauge), and venous catheters

• a suction apparatus, tourniquet, taped tongue blade, and tape

• laryngoscope and endotracheal tubes (adult and child)

If there is no 911 community emergency phone system, it is essential to have the phone number of the local paramedic emergency squad posted near all office telephones.

BLS also outlines methods for aiding persons who are choking. These methods include the Heimlich maneuver and appropriate manual techniques for removing foreign bodies from the oral pharynx. Epigastric thrusts should be attempted; up to 10–12 thrusts may be necessary. If these techniques fail to restore effective respiratory function, ventilation should be attempted. Using a finger sweep to clear a foreign body from the oral pharynx is recommended by the American Medical Association but is not indicated in many modern protocols. Transtracheal ventilation by means of cricothyrotomy may be necessary if other techniques fail to clear the airway.

The American Heart Association has established guidelines and procedures for ACLS. ACLS includes intubations, defibrillation, cardioversion, pacemaker placement, administration of drugs and fluids, and communication with ambulance and hospital systems. Because of the comprehensive and changing nature of ACLS algorithms, these procedures are beyond the scope of this chapter.

Competency in pediatric emergency care may be enhanced with training in pediatric life support (PLS) and PALS. In addition, ophthalmologists should be familiar with the ophthalmic manifestations of child abuse and abusive head trauma (shaken baby syndrome). These are discussed in BCSC Section 6, Pediatric Ophthalmology and Strabismus.

• Neumar RW, Shuster M, Callaway CW, et al. Part 1: Executive summary: 2015 American Heart Association Guidelines Update for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation. 2015:132(18 Suppl 2):S315–367.

Excerpted from BCSC 2020-2021 series: Section 1 - Update on General Medicine. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.