Cardiopulmonary resuscitation (CPR) is an emergency procedure that combines chest compressions often with artificial ventilation in an effort to manually preserve intact brain function until further measures are taken to restore spontaneous blood circulation and breathing in a person who is unconscious. CPR is a lifesaving procedure useful in many emergencies, including heart attack or near drowning, in which someone's breathing or heartbeat has stopped.
CPR should be performed immediately on any person who has become unconscious and is found to be pulse-less.
CPR, in its most basic form, can be performed anywhere without the need for specialized equipment. Some hospitals and EMS systems employ devices to provide mechanical chest compressions.
CPR alone is unlikely to restart the heart. Its main purpose is to restore partial flow of oxygenated blood to the brain and heart. The objective is to delay tissue death and to extend the brief window of opportunity for a successful resuscitation without permanent brain damage. Administration of an electric shock to the subject's heart, termed defibrillation, is usually needed in order to restore a viable or "perfusing" heart rhythm.
A cardiac defibrillator provides an electrical shock to the heart via 2 electrodes placed on the patient’s torso and may restore the heart into a normal perfusing rhythm.
CPR serves as the foundation of successful cardiopulmonary resuscitation, preserving the body for defibrillation and advanced life support
In its full standard form, CPR comprises the following 3 steps, performed in this order:
The acronym CAB which stands for Compressions, Airway and Breathing can be used to help people remember the order to perform the steps of CPR.
For lay rescuers, compression-only CPR (COCPR) is recommended.
1. CPR is most easily and effectively performed by laying the patient supine on a relatively hard surface, which allows effective compression of the sternum. Delivery of CPR on a mattress or other soft material is generally less effective.
2. The health care provider giving compressions should be positioned high enough above the patient to achieve sufficient leverage, so that he or she can use body weight to adequately compress the chest.
3. In the hospital setting, where patients are in gurneys or beds, appropriate positioning is often achieved by lowering the bed, having the CPR provider stand on a step-stool, or both.
4. In the out-of-hospital setting, the patient is often positioned on the floor, with the CPR provider kneeling over him or her.
Before starting CPR, check:
Is the environment safe for the person? Check that there is no danger to you or others.
Is the person conscious or unconscious?
If the person appears unconscious, tap or shake his or her shoulder and ask loudly, "Are you OK?"
If the person doesn't respond and two people are available, one should call an emergency number and one should begin CPR. If you are alone and have immediate access to a telephone, call the emergency number before beginning CPR, unless you think the person has become unresponsive because of suffocation (such as from drowning). In this special case, begin CPR for one minute and then call the emergency number.
Remember the CAB acronym
For an unconscious adult, CPR is initiated as follows:
Compressions: Restore blood circulation
Put the person on his or her back on a firm surface.
Kneel next to the person's neck and shoulders.
Place the heel of one hand on the patient’s sternum and the other hand on top of the first, fingers interlaced.
Extend the elbows and the provider leans directly over the patient.
Press down, compressing the chest at least 2 inches (approximately 5 centimetres) but not greater than 2.4 inches (approximately 6 centimetres).
Release the chest and allow it to recoil completely.
Push hard at a rate of 100 to 120 compressions a minute.
The key phrase for chest compression is, “Push hard and fast”.
If you haven't been trained in CPR, continue chest compressions (Untrained bystanders should perform chest compression–only CPR, COCPR) until there are signs of movement or until emergency medical personnel take over. If you have been trained in CPR, go on to checking the airway and rescue breathing.
Airway: Clear the airway
If you're trained in CPR and you've performed 30 chest compressions, open the person's airway using the head-tilt, chin-lift manoeuvre. Put your palm on the person's forehead and gently tilt the head back. Then with the other hand, gently lift the chin forward to open the airway.
Look in the patient’s mouth for a foreign body blocking the airway.
Check for normal breathing, taking no more than five or 10 seconds. Look for chest motion, listen for normal breath sounds, and feel for the person's breath on your cheek and ear. Gasping is not considered to be normal breathing. If the person isn't breathing normally and you are trained in CPR, begin mouth-to-mouth breathing. If you believe the person is unconscious from a heart attack and you haven't been trained in emergency procedures, skip mouth-to-mouth breathing and continue chest compressions.
Breathing: Breathe for the person
Rescue breathing (also known as ventilation) can be mouth-to-mouth breathing or mouth-to-nose breathing if the mouth is seriously injured or can't be opened. A bag-valve-mask (BVM) can be used if available.
With the airway open (using the head-tilt, chin-lift manoeuvre), pinch the nostrils shut for mouth-to-mouth breathing and cover the person's mouth with yours, making a seal.
Prepare to give two rescue breaths. Give the first rescue breath, lasting one second and watch to see if the chest rises. If it does rise, give the second breath. If the chest doesn't rise, repeat the head-tilt, chin-lift manoeuvre and then give the second breath. Thirty chest compressions followed by two rescue breaths is considered one cycle. Be careful not to provide too many breaths or to breathe with too much force.
Resume chest compressions to restore circulation.
If the person has not begun moving after five cycles (about two minutes) and an automated external defibrillator (AED) is available, apply it and follow the prompts. Administer one shock, then resume CPR, starting with chest compressions, for two more minutes before administering a second shock. If you're not trained to use an AED, an emergency medical operator may be able to guide you in its use. If an AED isn't available, go to step 5 below.
Continue CPR until there are signs of movement or emergency medical personnel take over.
To prevent provider fatigue or injury, new providers should intervene every 2-3 minutes (ie, providers should swap, giving the chest compressor a rest while another rescuer continues CPR).
For an intubated patient, continuous compressions should be given while ventilations are given 8-10 times per minute
To perform the BVM or invasive airway technique, the provider should do the following:
Ensure a tight seal between the mask and the patient’s face.
Squeeze the bag with one hand for approximately 1 second, forcing at least 500ml of air into the patient’s lungs.
To perform CPR on a child
The procedure for giving CPR to a child age 1 through 8 is essentially the same as that for an adult. The following CPR to be performed on a child should be recommended:
If you're alone, perform five cycles of compressions and breaths on the child (this should take about two minutes) before calling your local emergency number or using an AED.
Use two hands, or only one hand if the child is very small, to perform chest compressions. Press straight down on (compress) the chest about 2 inches (approximately 5 centimetres). If the child is an adolescent, push straight down on the chest at least 2 inches (approximately 5 centimetres) but not greater than 2.4 inches (approximately 6 centimetres).
Breathe more gently.
Use the same compression-breath rate as is used for adults: 30 compressions followed by two breaths. This is one cycle. Following the two breaths, immediately begin the next cycle of compressions and breaths. If there are two people conducting CPR, conduct 15 compressions followed by two breaths.
After five cycles (about two minutes) of CPR, if there is no response and an AED is available, apply it and follow the prompts. Use paediatric pads if available, for children ages 1 through 8. If paediatric pads aren't available, use adult pads. Do not use an AED for children younger than age 1. Administer one shock, then resume CPR, starting with chest compressions, for two more minutes before administering a second shock. If you're not trained to use an AED, an emergency medical operator may be able to guide you in its use.
Continue until the child moves or medical help arrives.
To perform CPR on a baby
Most cardiac arrests in babies occur from lack of oxygen, such as from drowning or choking. If you know the baby has an airway obstruction, perform first aid for choking. If you don't know why the baby isn't breathing, perform CPR.
To begin, examine the situation. Stroke the baby and watch for a response, such as movement, but don't shake the baby.
If there's no response, follow the CAB procedures below and time the call for help as follows:
If you're the only rescuer and CPR is needed, do CPR for two minutes (about five cycles) before calling your local emergency number.
If another person is available, have that person call for help immediately while you attend to the baby.
Compressions: Restore blood circulation
Place the baby on his or her back on a firm, flat surface, such as a table. The floor or ground also will do.
Imagine a horizontal line drawn between the baby's nipples. Place two fingers of one hand just below this line, in the centre of the chest.
Gently compress the chest about 1.5 inches (about 4 centimetres).
Count aloud as you pump in a fairly rapid rhythm. You should pump at a rate of 100 to 120 compressions a minute.
Airway: Clear the airway
After 30 compressions, gently tip the head back by lifting the chin with one hand and pushing down on the forehead with the other hand.
In not more than 10 seconds, put your ear near the baby's mouth and check for breathing: Look for chest motion, listen for breath sounds, and feel for breath on your cheek and ear.
Breathing: Breathe for the baby
Cover the baby's mouth and nose with your mouth.
Prepare to give two rescue breaths. Use the strength of your cheeks to deliver gentle puffs of air (instead of deep breaths from your lungs) to slowly breathe into the baby's mouth one time, taking one second for the breath. Watch to see if the baby's chest rises. If it does, give a second rescue breath. If the chest does not rise, repeat the head-tilt, chin-lift manoeuvre and then give the second breath.
If the baby's chest still doesn't rise, examine the mouth to make sure no foreign material is inside. If an object is seen, sweep it out with your finger. If the airway seems blocked, perform first aid for a choking baby.
Give two breaths after every 30 chest compressions. If two people are conducting CPR, give two breaths after every 15 chest compressions.
Perform CPR for about two minutes before calling for help unless someone else can make the call while you attend to the baby.
Continue CPR until you see signs of life or until medical personnel arrive.
CPR, in its most basic form, can be performed anywhere without the need for specialized equipment. Regardless of the equipment available, proper technique is essential.
Universal precautions (ie, gloves, mask, gown) should be taken. However, in the vast majority of patients who are resuscitated in the out-of-hospital setting, CPR is delivered without such protections, and no cases of disease transmission via CPR delivery have been reported.
Some hospitals and emergency medical services (EMS) systems employ devices to provide mechanical chest compressions.
Complications of CPR include the following:
Fractures of ribs or the sternum from chest compression (widely considered uncommon)
Gastric insufflation from artificial respiration using noninvasive ventilation methods (eg, mouth-to-mouth, BVM); this can lead to vomiting, with further airway compromise or aspiration; insertion of an invasive airway (eg, endotracheal tube) prevents this problem
For patients with cardiac arrest, survival rates and neurologic outcomes are poor, though early appropriate resuscitation, involving cardiopulmonary resuscitation (CPR), early defibrillation, and appropriate implementation of post–cardiac arrest care, leads to improved survival and neurologic outcomes. Targeted education and training regarding treatment of cardiac arrest directed at emergency medical services (EMS) professionals as well as the public significantly increase cardiac arrest survival rates.
When someone's blood flow or breathing stops, seconds count. Permanent brain damage or death can happen quickly. When the heart stops, the lack of oxygenated blood can cause brain damage in only a few minutes and a person may die within eight to 10 minutes.
If you know how to perform cardiopulmonary resuscitation (CPR), you could save a life. CPR is an emergency procedure for a person whose heart has stopped or is no longer breathing. CPR can maintain circulation and breathing until emergency medical help arrives.
Even if you haven't had training, you can do "hands-only" CPR for a teen or adult whose heart has stopped beating ("hands-only" CPR isn't recommended for children). "Hands-only" CPR uses chest compressions to keep blood circulating until emergency help arrives. If you've had training, you can use chest compressions, clear the airway, and do rescue breathing. Rescue breathing helps get oxygen to the lungs for a person who has stopped breathing. To keep your skills up, you should repeat the training every two years.
It's far better to do something than to do nothing at all if you're fearful that your knowledge or abilities aren't 100 percent complete. Remember, the difference between your doing something and doing nothing could be someone's life.
If you've previously received CPR training but you're not confident in your abilities, then just do chest compressions at a rate of 100 to 120 a minute.
To learn CPR properly, take an accredited first-aid training course, including CPR and how to use an automated external defibrillator (AED). If you are untrained and have immediate access to a phone, call your country’s emergency number before beginning CPR. The dispatcher can instruct you in the proper procedures until help arrives.
Use of automated external defibrillator (AED)
Prompt defibrillation is an important part of the resuscitation process, along with effective CPR.
Some safety points to remember include:
AEDs must only be used for victims who are unresponsive and not breathing normally.
CPR must be continued until the AED is turned on and pads attached.
The pads should be placed as instructed and not touching each other.
The rescuer should then follow the AED instructions.
Care should be taken for all people present not to touch the person during shock delivery.
Standard adult AEDs and pads are suitable for use in children over eight years of age.
Ideally, paediatric pads and an AED with a paediatric capability should be used for children between one and eight years.
These pads also are placed as per an adult, and the pads come with a diagram of where on the chest they should be placed.
If the AED does not have a paediatric mode or paediatric pads, then the standard adult AED and pads can be used.
Do not use an AED on children under one year of age.
Note: Do not use an AED on children under one year of age.
The information above provides guidance only, and should not be relied upon as a substitute for medical advice. We recommend you attend a first-aid training course. It pays to have first aid skills because they can't be learned in an emergency situation.