Cardiopulmonary resuscitation (CPR) is an emergency technique used when a person’s heart has stopped beating and breathing has stopped. Millions of people receive CPR training each year, and its use has been shown to increase the survival rate of people who are suffering from otherwise fatal conditions.

CPR is used in a variety of situations, including drug overdose, near drowning and electrical shock. It is also used when a person has entered cardiac arrest, or the heart has stopped beating (most often due to an abnormal heart rhythm called ventricular fibrillation). Patients may avoid sudden cardiac death if they receive CPR until emergency medical help arrives (who may use a defibrillator to restore a natural heart rhythm).

Although information about CPR may be obtained in a variety of ways, only an accredited CPR class (e.g., those offered by the American Red Cross or the American Heart Association) can offer people CPR certification.

CPR cannot always save a person’s life. In addition, even when CPR is administered correctly, there is a risk of harming the person on whom it is being performed. Anyone administering CPR should be aware of importance of administering CPR in certain situations.

 

Cardiopulmonary resuscitation (CPR) is an emergency technique that anyone can learn to help someone whose heart and/or breathing has stopped. The heart and/or breathing can stop from a number of causes, including heart attack, choking, drowning or electric shock. When breathing has stopped, blood cannot receive oxygen, and when the heart has stopped (cardiac arrest), the blood cannot circulate to nourish the body. Therefore, it is vital for people in this emergency situation to receive medical treatment such as CPR within the first four minutes.

CPR does not restart a heart in ventricular fibrillation, but it can keep a victim alive until a defibrillator can be used to shock the heart back into a normal rhythm. Defibrillators are available at hospitals and in many ambulances, and are also becoming more available in malls, golf courses and other public places.

Using CPR, a rescuer can breathe for the victim and chest compressions can help some of the blood to circulate. Recent studies have demonstrated that CPR not only keeps a victim alive, it helps increase a survivor’s quality of life, probably because the rescuer may prevent or mitigate additional injury due to oxygen deprivation.

CPR can be performed by one person, but it is most effective when done by two people. One person performs the “mouth-to-mouth” breathing, and the other performs the chest compressions. The technique is not difficult to learn, and many organizations offer accredited courses in CPR, including the American Heart Association (AHA), American Red Cross, community centers, health clubs and YMCAs.

Ongoing research on various CPR methods serves to continually evaluate their safety and effectiveness, and organizations providing CPR training may periodically update their methods. For example, in 2005, the AHA published updated CPR guidelines, which form the basis for its new CPR training materials. Although knowing the latest CPR methods is important, there is no substitute for learning up-to-date CPR techniques from a qualified instructor.

The first step is to recognize the emergency. A heart attack, for instance, begins with symptoms such as a sudden shortness of breath (dyspnea), tightness in the chest or a feeling of being squeezed in the chest area. Learning to recognize the symptoms is vital. A recent study has suggested that many people mistake choking for a heart attack. The universal sign for choking is clutching the throat with both hands.

Cardiopulmonary resuscitation (CPR) is used whenever breathing and/or the heart stops. Before starting CPR, the rescuer must make sure the person is actually unconscious and not merely sleeping or resting by shaking the shoulder of the person and shouting “Are you OK?” Performing CPR on someone whose heart is functioning normally can itself cause the heart to stop (cardiac arrest).

If the person does not respond and the rescuer is alone, he or she should call 9-1-1 immediately and then begin CPR unless the victim is an infant, in which case it is vital to begin CPR immediately and then call 9-1-1. Experts agree that it is important to get oxygen into a distressed infant immediately. It is also recommended to administer CPR before calling 9-1-1 to adult victims of trauma, submersion and drug overdose. If others are present, the one most qualified or experienced in CPR should stay with the person in crisis while someone else calls 9-1-1 and is prepared to answer the following questions:

There are three principles of cardiopulmonary resuscitation (CPR), which are sometimes referred to as the ABCs of CPR: airway, breathing and circulation. The following is a general description of how CPR is performed on adults. For infants and children, the procedure is similar, although there are some important differences.

Airway: The rescuer makes sure the victim’s airway is clear. First, the victim should be carefully turned on his or her back (with the neck supported in case of neck injury).

Anything that may cause airway obstruction should be removed from the victim’s mouth. Liquids are wiped out with fingers covered by a piece of cloth. Using the index finger, the rescuer also “hooks out” any solids. If the airway is still blocked, the rescuer then performs the Heimlich maneuver. To perform the Heimlich maneuver on a person who is lying on his or her back, the rescuer kneels over the victim, straddling the victim’s thighs. One hand is placed over the other with the heel of the bottom hand on the stomach, slightly above the navel and below the rib cage. With a quick upward thrust, the rescuer presses into the stomach while being careful to direct the thrust upward and not down or to either side of the stomach. The rescuer is also careful not to push too high into the ribs. This maneuver will dislodge most obstructions and should be repeated as necessary until the airway is clear.

Previously, a “jaw thrust” method (moving the lower jaw forward) was recommended to open an unresponsive person’s airway. Although any method of opening an airway may cause potentially damaging movement of an injured spine, the American Heart Association (AHA) recommends the “head tilt-chin lift” method be used. This lifts the tongue away from the back of the mouth and opens the airway.

The head tilt-chin lift method may be performed as follows: The rescuer puts one hand on the victim’s forehead. The fingers of the other hand should be placed under the bony part of the lower jaw, near the chin. The rescuer then tilts the head back and gently lifts the jaw, without closing the victim’s mouth or pushing on the soft parts under the chin. It is important to avoid lifting the neck as this could cause injury.

Breathing: The rescuer takes no more than 10 seconds to check for normal breathing in an unresponsive victim. This may be done by observing the chest for signs of rising and falling breathing motions, or by placing an ear close to the victim’s mouth to listen and feel for exhalation. Gasping for breath is not considered normal breathing. A person who is gasping may be experiencing cardiac arrest and require CPR.

Once the need for CPR has been established, two rescue breaths (over one second per breath) should be provided immediately. This may be done as follows:

• The rescuer maintains the victim's open airway (e.g., the head tilt-chin lift). With a hand on the victim’s forehead, the rescuer pinches the victim’s nostrils closed so air cannot escape out of the victim’s nose.
  
  
• The rescuer takes a regular breath, covers the victim’s mouth with his or her own mouth to form a tight seal, and then exhales completely into the victim’s mouth twice. This should inflate the victim’s lungs, and the victim’s chest should visibly rise. If it does not, or there is resistance to the exhalations, the rescuer should perform the head tilt-chin lift again before providing the second breath. Previously, deep breaths were suggested. However, deep breaths are not necessary and regular breaths should be enough to cause the victim’s chest to rise.
  
  
• If mouth-to-mouth rescue breathing is not possible, the rescuer then attempts a procedure called mouth-to-nose. This technique is used if the mouth cannot be opened or the mouth is too damaged by injury to make a tight seal. The technique is the same as mouth-to-mouth, except the fingers on the chin close the mouth completely. Air is blown into the victim’s nose.

After the two rescue breaths have been administered, chest compressions should be begun immediately.

Circulation:  In response to the rescue breaths, lay rescuers were previously instructed to check for signs of circulation (e.g., normal breathing, coughing or movement) or a pulse (by checking the carotid artery in the neck). However, the AHA has found that these efforts may not be reliable and the time spent performing such checks is better applied to actually performing CPR.  

Thus, immediately after providing the initial two rescue breaths, rescuers should begin chest compressions. These may be done in the following manner:  

• The rescuer kneels next to the victim’s chest, halfway between the shoulder and the waist. Feeling for where the two halves of the rib cage join together, the rescuer finds the “V” notch in the center of the chest. Then the rescuer places the heel of one hand on the breastbone (sternum) next to the fingers that found the notch (about three fingers up from the notch, between the nipples). The palm should be able to feel the bones underneath.
  
  
  
  
  
• The rescuer then places the other hand on top and interlocks the fingers, making sure to use only the palms. The fingers should not press into the victim’s ribcage.
  
  
• Chest compressions begin. The rescuer straightens the arms, locks the elbows and leans forward until his or her shoulders are over the rescuer's hands. Using his/her weight, the rescuer presses the sternum until it sinks from 1.5 to 2 inches. The pressure is then relaxed. Prior recommendations had the rescuer delivering chest compressions at a rate of one per second. This has been revised to ensure faster compressions – about 100 per minute - realizing that the patient will receive fewer than that due to pauses for the breaths (below). The AHA recommends that rescuers push hard, push fast, and allow the victim’s chest to completely recoil after each compression. Interruptions in the delivery of chest compressions should be avoided.

Cycles of chest compressions and ventilations may now begin. The AHA now recommends that 30 compressions be given at a time, followed by two breaths. This 30:2 compression-to-ventilation ratio should be given to all victims, no matter their age. This is an update from earlier recommendations and is intended to simply lay rescuer CPR.

These cycles of compressions and ventilations should continue until emergency medical help arrives or the victim recovers and is breathing on his or her own.

For children between the ages of 1 and 8, CPR is delivered much as it is for adults, except chest compressions may be performed with the heel of only one hand and the chest only needs to be pressed down about 1 to 1.5 inches.

For an infant less than 1 year old, the CPR technique is a little different. The rescuer checks for consciousness by tickling the infant’s feet or pinching the skin. Airway obstructions may be cleared with a back slap or chest thrust. Also, unless a spinal, neck or back injury is suspected, the rescuer gently places the baby on its back on a hard, flat surface, keeping the back straight and firmly supporting the head and neck. The infant’s chin is lifted and the head is tilted back slightly to move the tongue away from the windpipe, being careful not to overextend the head. The chest is exposed and the rescuer listens and watches for breathing for about five seconds. Next steps usually include:

• If the infant is breathing, but appears to be choking, the rescuer should begin back blows to clear the airway. Using the thigh or lap for support, the infant is laid face down along the rescuer’s forearm, with the child’s chest in the rescuer’s hand and the jaw between the thumb and index finger. The infant’s head is kept lower than his or her body. The rescuer then delivers five forceful blows between the infant’s shoulder blades with the heel of the rescuer’s other hand. The baby is then turned over to face upward. The rescuer places two fingers on the middle of the breastbone, just below the nipples, and gives five quick thrusts down, compressing the breast 0.5 inch to 1 inch each time. Afterwards, the rescuer should check to see if the compressions dislodged the object by opening the child’s mouth with the thumb and index finger. Placing a thumb over the infant’s tongue, the rescuer should remove any visible and loose objects.
  

It will take the paramedics a few moments to set up their equipment, therefore the rescuer should keep performing cardiopulmonary resuscitation (CPR) until told to stop. The rescuer should tell the paramedics the victim’s medical history (if known), including any allergies or reactions the victim may have to medication. The paramedics will take it from there.

Both CPR and defibrillation should be begun within minutes of collapse in order for resuscitation to be successful. Brain death begins 4 to 6 minutes after cardiac arrest – if no CPR or defibrillation occurs during that time. Effective and timely CPR can double a victim’s chance of survival, according to the American Heart Association (AHA). Without CPR, a victim’s chance of survival decreases 7 to 10 percent for every minute of delay until defibrillation, according to the AHA. Although the electrical shock delivered by a defibrillator is important, recent studies have emphasized the importance of effective bystander CPR.

Before performing cardiopulmonary resuscitation (CPR), a rescuer must identify that a person’s breathing or pulse has stopped. CPR performed on a healthy person can actually cause the person to go into cardiac arrest. For this reason, CPR training should never be practiced on a person.

Even when properly administered, CPR cannot always save a person’s life. In addition, there may be a risk of harming the person on whom it is administered. For example, when an unresponsive person’s airway is opened (e.g., even with the preferred head tilt-chin lift method), there is a risk of causing further damage to a person with an injured spine. Chest compressions that are pushed into the chest too far may damage internal organs. However, in many case, the benefits of CPR outweigh its risks.

It is not uncommon for a person to vomit during CPR administration due to air being forced into the stomach. If this happens, a rescuer should turn the person over to one side, clean out the mouth and then re-establish an open airway as before.

Performing CPR, especially by only one person, is strenuous work, and the rescuer may quickly begin to tire. Studies conducted by the American Heart Association (AHA) showed that only a small percentage of single–rescuers, practicing on mannequins, were able to provide the recommended number of compressions/breaths in spite of their best efforts.

Research has indicated that many bystanders do not perform CPR when it is needed. This may be due to the public’s perceived risk of disease, especially from performing mouth-to-mouth resuscitation. The most commonly cited reason for not performing mouth-to-mouth was the risk of getting AIDS. However, the AHA knows of no reports of contracting AIDS during CPR, whether on a mannequin or a person who has experienced cardiac arrest. According to the Centers for Disease Control and Prevention, there is no evidence that AIDS is transmitted by saliva. Other social or economic factors may also cause some bystanders not to perform CPR when necessary.

For adults:

• Recognize the symptoms. Is the person having a heart attack or choking?
  
  
• If the person appears unconscious, shake him or her and shout, “Are you OK?”
  
  
• If there is no response, call 9-1-1 immediately.  
  
  
• Open airway. Turn the victim on his or her back, supporting the neck. Remove any vomit or foreign material. If the airway is still blocked, perform the Heimlich maneuver until the airway is clear. Use the held-tilt, chin-lift method to open the airway.
  
  
• Check and administer breathing. Spend no more than 10 seconds checking for signs of breathing. If none are present, pinch the victim’s nostrils closed so that air cannot escape from the nose. Rescuers should cover the victim’s mouth with their own mouth to form a tight seal. Take a regular breath and exhale completely into the victim’s mouth until the chest inflates. If it doesn’t, check for and remove any blockages. Two initial breaths should be given prior to beginning chest compressions. 
  
  
• Begin chest compressions. Place the heel of one hand on the victim’s breastbone, between the nipples. Place the other hand on top and interlock the fingers, making sure to use only the palms. Do not allow the fingers to press into the ribcage. Press the breastbone until it sinks from 1.5 to 2 inches. Relax pressure. Repeat at a rate of a bit more than one per second – about 100 per minute.
  
  
• Continue cycle of compressions and ventilations. Alternate 30 compressions with two breaths (30:2 ratio). If there are two rescuers present, periodically switch positions to fight fatigue without interrupting the rhythm.

For a child (ages 1 through 8)

The procedure is the same as for adults, except that chest compressions may be performed with the heel of only one hand, and the chest only needs to be pressed down about 1 to 1.5 inches.

For an infant

• Check for consciousness by tickling the infant’s feet or pinching the skin. Gently place the infant on its back on a hard, flat surface. Keep the back straight and support the head and neck. Lift the chin and tilt the head back slightly to move the tongue away from the windpipe. Watch for breathing for about five seconds.
  
  
• If the baby is not breathing, it is vital to get air into the infant before dialing 9-1-1. Cover the mouth and nose completely and gently exhale twice, each lasting one second with a pause in between. If the chest does not inflate, reposition the head and try again. After two initial rescue breaths are provided, chest compressions should begin immediately.
  
  
• Using two fingers in the center of the infant’s chest (just below the nipple line), press down to compress the infant’s chest. As with adult CPR, chest compressions should be given at the rate of 100 per minute, with 30 at a time, followed by two breaths. This cycle should be continued for two minutes before leaving the child to call 9-1-1.
  
  
• If the child is not breathing and appears to be choking, begin back blows. Lay the infant down along your forearm with the child’s chest in your hand and the jaw between the thumb and index finger. Use your thigh or lap for support, and keep the baby’s head lower than its body. Deliver five forceful blows between the shoulder blades with the heel of your hand. If necessary, turn the baby up to perform a modified Heimlich maneuver. Place two fingers on the middle of the breastbone, just below the nipples, and give five thrusts down, compressing the breast no more than 1 inch each time. Open the mouth, place a thumb over the tongue and remove any visible and loose objects.

Preparing questions in advance can help patients have more meaningful discussions with their doctor. Patients may wish to ask their physicians the following questions related to cardiopulmonary resuscitation (CPR):

1. How do I properly perform CPR?
   
   
2. How do I know if a person requires CPR? What are the signs that a person has stopped breathing?
   
   
3. What is the proper way to administer CPR if there are two rescuers working together?
   
   
4. How does performing CPR on a child differ from an adult?
   
   
5. Should I immediately begin to perform CPR or should I call 9-1-1 first?
   
   
6. Are there any instances when CPR should not be performed?
   
   
7. Can CPR be safely performed on an infant? How can I be sure I am not injuring the infant?
   
   
8. Could I contract any diseases while administering CPR?
   
   
9. Is it safe to perform CPR if I am pregnant?
   
   
10. Can you refer me to a certified CPR instructor?