Cardiopulmonary resuscitation


Cardiopulmonary resuscitation, commonly called CPR, is a lifesaving procedure performed when a person has stopped breathing or a person's heart has stopped beating.

(Fig 3.4a; Fig 3.4b; Fig 3.4c; Fig 3.4d; Fig 3.4e; Fig 3.4f.)
Call an ambulance. Immediately start CPR with compressions. Push hard on the center of the chest 30 times (E) at a rate of 100 compressions/minute. If you're trained in CPR, continue by opening the airway with a head tilt (B). Pinch the victim's nose shut, inhale normally, and create an airtight seal between your mouth and the victim's (C). Give two short breaths and watch for chest rise. Continue compressions and breaths until trained help arrives.


The purpose of CPR is to bring oxygen to the individual's lungs and to keep blood circulating so oxygen gets to every part of the body. When a person is deprived of oxygen, permanent brain damage can begin in as little as four minutes and death can follow only minutes later. When performed quickly enough, CPR can save lives in such emergencies as heart attack or sudden cardiac arrest, electric shock, near-drowning, drug overdose, and other conditions in which the heart has stopped and there is no breathing.


In 2010, over 300,000 Americans were expected to die of sudden cardiac arrest. Some of these people could be saved by the immediate application of CPR. In October of 2010, the instructions for performing CPR by people who have not received formal CPR training or who are not healthcare professionals was changed.

There are three physical symptoms that indicate a potential need for CPR to be performed immediately and for emergency medical support to be called: unconsciousness, absence of breathing, and no pulse detected (absence of heartbeat).


Unconsciousness is the loss of all awareness and failure to respond to questions, touch, or gentle shaking. When unconscious, a person cannot cough or clear the throat, which may allow the windpipe to become blocked, causing suffocation and death. People with a major illness or injury or who have had recent surgery are at risk for losing consciousness. Alcohol or drug overdose also can cause unconsciousness.

Individuals who are unconscious and not breathing need immediate CPR. Individuals who are unconscious and breathing (e.g., a traumatic head injury) need emergency medical care, and should be watched to assure that their breathing continues. If the person is conscious, he or she may be choking and need other medical help but does not need CPR. Fainting is a brief period of unconsciousness, which may occur from dehydration (lack of body fluids), low blood pressure, low blood sugar, excessive bleeding, or emotional distress. This is a temporary condition. Again, the individual may need medical help but does not normally need CPR because people who faint normally continue to breathe without assistance.

Failure to breathe

Apnea is the lack of spontaneous breathing. The individual may become limp and lifeless, have a seizure, or turn bluish (a sign of inadequate oxygen). Prolonged apnea is called respiratory arrest. In children, this can quickly lead to cardiac arrest in which the heart stops beating. In adults, cardiac arrest usually happens first, followed by respiratory arrest. In adults, common causes of apnea and respiratory arrest include choking, drug overdose, near-drowning, head injury, and cardiac arrest. In children, the causes may be different, such as prematurity, swelling of the airways (e.g., an asthma attack, an allergic reaction), choking on a foreign object, seizures, regurgitating food or near-drowning.

No pulse detected

If the rescuer is unable to detect a pulse or has difficulty feeling a pulse, it may be due to cardiac arrest (i.e., the heart has stopped beating). Not all rescuers are adept at finding a pulse either in the wrist or the carotid artery of the neck. Rescuers who are uncertain about whether there is a pulse should err on the side of caution and begin CPR.

Medical help and possibly CPR are needed immediately if any of these three symptoms are found. Time is critical. A local emergency number should be called immediately. If more than one person is available to help, one person can call the local emergency medical service (911 in the United States), while the other person begins CPR. If needed, the emergency dispatcher (the person who picks up emergency calls) can give step-by-step CPR instructions over the telephone.

Performing CPR

The explanation below is not a substitute for CPR training and is intended as a descriptive guideline only.

In 2010 the American Heart Association recommended that the three traditional steps for performing CPR be re-ordered for lay people who have had little or no training in CPR. This change applies to performing CPR on adults, children, and infants, but not on newborns. Formerly the steps were (in order): clear the airways, check for breathing, and begin chest compressions. This was known as the A-B-C method of CPR.

The 2010 recommendations have changed the order. Chest compressions should begin first, followed by clearing the airways and checking for breathing if the rescuer is adequately trained. There are two reasons for this change. First, most people have residual oxygen in their lungs from their last breath. It is most important that the blood be kept circulating continuously through chest compressions so that this oxygen reaches the brain without delay. Second, many lay people are reluctant to do mouth-to-mouth breathing on a stranger. After reviewing multiple studies that examined the outcome of CPR done by lay people, the American Heart Association has determined that chest compressions alone (hands-only CPR) are almost as effective as chest compressions with breathing, and that breathing need not be done by people untrained in CPR. The American Heart Association hopes that this change will encourage more bystanders to come to the aid of a cardiac arrest victim and potentially save more lives.

The steps to be followed in CPR by a layperson are as follows:

  • If the victim appears to be unconscious, he or she should be shaken or tapped gently to check for any sign of consciousness. If there is no response, the rescuer should call emergency medical services immediately, or (preferably) send someone else to call for help. If the rescuer is alone, he or she should call for emergency services before beginning CPR.
  • The victim should be placed on his or her back on a level surface such as the ground or the floor unless there is some sign of neck or back injuries, in which case the individual should not be moved. It is better to err on the side of caution and not move the individual if there is any question about whether moving will cause additional damage.
  • The rescuer then places the heel of one hand in the middle of the chest, putting the other hand on top of the first, interlacing the fingers, and pressing down so that the chest is compressed by at two inches. Hard and fast compressions are essential if CPR is to be effective. The rescuer should not worry about damaging the breastbone or ribs. (These will heal; death is permanent.) When performing compressions, the rescuer should keep the elbows straight, center his or her shoulders over the individual, develop an upand-down rhythm, and keep the hands firmly on the individual's chest. Compressions should be done on the center of the chest midway between the nipples. Compressions should be hard and fast at a rate of at least 100 times per minute. That is about the same rhythm as the beat of the Bee Gee's song "Stayin' Alive." Compressions should continue at this rate until the victim begins to breathe spontaneously or until trained medical help arrives.
    If the rescuer has been trained in CPR, he or she may jut the victim's jaw forward, tilt the head back, and open the mouth. Using the finger, the rescuer should clear any debris from inside the mouth. The rescuer then should put his or her ear to the victim's open mouth, look for chest movement, listen for air flowing through the mouth or nose, and feel for air on his or her cheek. If there is no breathing, the rescuer pinches the individual's nose shut, makes a seal over the individual's mouth with his or her own mouth, and gives the individual two puffs of breath big enough to make the chest rise. If the chest does not rise, the individual's head should be repositioned to help ensure the tongue is kept away from the windpipe, then the rescuer should try again to give a breath. Chest compressions should continue with two puffs of breath given for every 50 compressions (two puffs per minute) until help arrives or the victim begins breathing spontaneously.


Rescuers should observe the following:

  • Do not leave the individual alone.
  • Do not give the individual anything to eat or drink.
  • Avoid moving the individual's head or neck if spinal injury is a possibility. To check for breathing when spinal injury is suspected, the rescuer should only listen for breath by the individual's mouth and watch the chest for movement.
  • Do not place a pillow under the individual's head.


As CPR is performed in emergency situations, there is no time to prepare the recipient for the procedure. It is necessary to place lay the recipient on a flat surface facing up before administering compressions.

Training in CPR is the best preparation the rescuer. Training is not difficult or expensive. The American Heart Association provides CPR instruction for the community, schools, and workplace, along with health care settings. Courses vary from short programs to teach laypersons the basics of CPRto advanced cardiac life support certification for healthcare professionals. CPR is taught as part of many first aid courses.

In addition, the American Heart Association has a 22-minute long self-directed program called CPR Anytime in an effort to prepare the public and people who would not otherwise attend a CPR course to be able to respond to an emergency with core CPR skills. CPR Anytime does not lead to certification, but research has shown that the program is effective in quickly training the lay public and could prove to be a valuable tool in increasing the overall number of CPR-prepared individuals.


When CPR is initiated, emergency responders have ideally already been notified and are on the way to the scene. It is important to stay with the affected person and continue CPR until breathing and circulation are restored and/or emergency medical personnel arrive. When emergency personnel assume care of the individual, the person who initially provided CPR can often be helpful by providing information to emergency responders.


Minor injuries such as bruising can occur with chest compressions. Sometimes chest compressions can result in one or more breaks in the ribs and accompanying damage to internal organs, especially in young children, the elderly, or debilitated persons. The American Heart Association states, however, that in the event of a suspected cardiac arrest, even CPR performed by an untrained bystander who receives instructions from an emergency dispatcher is more beneficial than the risk of injury in a person who is actually not in cardiac arrest.


People with serious health conditions can follow these general guidelines:

  • Risk factors that contribute to heart disease should be reduced or eliminated. People can reduce risks if they stop smoking, lower blood pressure and cholesterol, lose excess weight, and reduce stress.
  • Illegal recreational drugs should be avoided.
  • Seeing a doctor regularly and being aware of any disease conditions or risk factors can help prevent or complicate illness, as can seeking and following the doctor's advice about diet and exercise.