Cardiopulmonary resuscitation

CPR or Cardiopulmonary resuscitation is an emergency first aid procedure to help someone who has lost their ability to breathe and their pulse, i.e., their noticeable heartbeat. It is a response to a condition known as cardiac arrest, in which heartbeat and breathing have stopped. Cardiac arrest is a condition nearly everyone experiences in the last few minutes of life, after drawing their last breath, and refers to a period in which the heart muscle still has some residual life in it and may sometimes be brought back to normal functioning by emergency techniques. CPR is appropriate for otherwise healthy persons experiencing sudden cardiac death, due perhaps to massive heart attacks or heart rhythm disturbances, and can keep the victims alive until emergency personnel arrive. It is also used effectively for victims of drowning, electrocution or choking, or those suffering from drug or other substance overdoses. CPR is commonly taught to ordinary people who may be the only persons present in the crucial few minutes before emergency personnel are available.

Table of contents

1 Effectiveness 2 History 3 First Aid 3.1 AIRWAY 3.2 BREATHING 3.3 CIRCULATION 3.4 CPR for children age twelve months to eight years 3.5 CPR for infants 3.6 Note 4 CPR Training 5 See also

Effectiveness

CPR is not usually effective on its own. When someone has lost their heartbeat (cardiac arrest), the most effective remedy is a technique known as "defibrillation", using an electronic shock to try to restore the correct heart rhythm. However, in cases in which the victim has gone into respiratory arrest but still has a heartbeat (as might happen in drowning, choking or overdosing on depressive drugs such as opiates or tranquilizers) the rescue breathing part of CPR is a certain life saver.

In cardiac arrest, CPR can keep the victim "viable" for a few extra minutes, to allow the arrival of a defibrillator on the scene. When CPR is started within minutes of the victim's collapse, and when a defibrillator is used within ten minutes of the victim's collapse, the save rate is about a third. CPR is almost never effective on a victim after more than about 15 minutes after collapse, due to brain damage, except in some cases of "hypothermia" - cardiac arrest due to overexposure to cold temperatures. The cold seems to exert a protective effect on the victim and there are instances of hypothermia victims being revived through CPR, defibrillation and advanced, hospital-based warming techniques, after a half an hour or more.

History

CPR was created by Peter Safar in the 1950s; he wrote his book ABC of resuscitation (A for airway, B for Breathing, C for Circulation, see below) in 1957. It was first promoted as a technique for the public to learn in the 1970s. Early marketing efforts oversold the effectiveness of CPR in rescuing heart attack and other victims. The standards for CPR, in the United States, are established by the American Heart Association. Re-written every several years, most recently in 2000, these standards now have a more conservative view of the potential of CPR as a bystander intervention, and now stress defibrillation as the more definitive intervention.

First Aid

FIRST send someone to call for help using the Emergency telephone number (911 in the US and Canada, 112 in Europe) to activate the emergency medical services. CPR can only buy time to apply advanced cardiac life support. Without advanced cardiac life support, CPR is useless. If you are alone, administer one minute of CPR -- use 1 to 2 minutes to call for help -- then return and continue CPR until help arrives.

Three simple steps to CPR

AIRWAY

Try to get a response by shaking and yelling at the victim. If there is no reaction, place victim flat on his or her back on a hard surface. Open the victims' airway by tilting their head back with one hand while lifting up their chin with the other hand. If there is a chance of neck injury just lift up the chin. Tilting of the head in the presence of injury to the spine or the neck could result in further injury to the spinal column.

BREATHING

(also known as "rescue breathing")

Put your cheek close to the victims' nose and mouth while looking at the victims' chest, to

look, listen, and feel for breathing (5-10 seconds) If there is no breathing, pinch victim's nose closed and breath two full breaths into the victim's mouth.

If breaths won't go in, reposition their head and try again to give breaths. If the airways are still blocked, perform abdominal thrusts (Heimlich maneuver). In the event the head tilt/chin lift maneuver was not performed due to suspected neck/spine injury and the breaths do not enter the lungs, head tilt/chin lift should be done anyway.

CIRCULATION

Check for a pulse by feeling for 5-10 seconds at side of the victims' neck.

• If there is a pulse but the victim is not breathing, give breaths at rate of 1 breath every 5 seconds (12 breaths a minute).
• If there is no pulse, begin chest compressions as follows. The compressions will pump blood around manually until hopefully the body can take over:

Kneel next to the victim's chest. To find the correct hand position, place the heel of the hand closest to the feet on the lower part of the ribcage. Place your other hand on top of the first. You can either interlace your fingers or keep them straight, but to avoid injuring the ribs, only the heel of your hand should touch the chest.

Shift your weight forward on your knees until your shoulders are directly over your hands and your elbows are locked. Bear down and then come up, bear down and come up, keeping your elbows locked. In order to create enough pressure to circulate the blood, you must depress the chest of an average adult 1 1/2 to 2 inches with each compression.

You should compress the chest at a rate of 80-100 times a minute (plus have time to do rescue breathing, if required). To get the right speed and rhythm, count out loud as you do the compressions, saying "1 and 2 and 3 and four and five!" Rest on each "and," then compress on each number. Each series of 5 should take about 3 seconds.

After each 15 compressions (counting to 5, 3 times), perform 2 rescue breaths. Take your hands off the chest, place them on the chin and forehead as before, pinch the nose, seal the mouth, and give 2 strong breaths, watching out of the corner of your eye for the chest to rise. Also have someone check for you if possible.

Go back to the chest, find the correct hand position again, and do 15 more compressions, followed by 2 more breaths. Repeat this cycle of 15 and 2 for a total of 4 times, which takes about 1 minute. Then check again for pulse and breathing. If neither has returned, you must continue alternating compressions and breathing until the patient revives, qualified help comes, or you are too exhausted to continue.

Recent studies have suggested that, for some patients, the time lost due to switching back and forth between mouth-to-mouth breathing and compressions may be harmful. Rescue breathing is important for patients whose oxygen levels are low (drowning victims, for example), but an uninterrupted series of chest compressions may be best for those who are known not to have asphyxiation issues (i.e., people who were walking around and talking just before they collapsed from a heart attack).

Common mistakes in performing chest compressions include rocking back and forth and bending the elbows. It is also important to note that, particularly in elderly patients, crepitations will often occur. Crepitations are the shattering of bones in the rib cage and sternum. They can be both heard and felt.

CPR for children age twelve months to eight years

Children have less lung capacity and a somewhat faster respiration rate. Also, compressions should be considerably less forceful than those used on adults.

The sequence of CPR for children is as follows:

1. ESTABLISH UNRESPONSIVENESS (4-10 SECONDS)

You must quickly determine if injury is present and determine consciousness. If head, neck, or spinal injury is suspected, great care must be exercised in positioning the child on her back on a firm flat surface. Turn and position the child, supporting the head and neck to avoid spinal cord injury caused by rolling, twisting, or tilting the head and neck.

A conscious child struggling to breathe will often find the best position to keep a partially obstructed airway open and should be allowed to maintain that position until medical help is available. If the young victim is unresponsive, position the child or infant on the back on a firm, flat surface and begin CPR.

Call for help after conducting CPR for 1 minute as below. If the child is conscious but suffering respiratory distress, do not waste time on CPR maneuvers but get the child to medical help as soon as possible. (Unresponsive children should receive CPR as they are rushed to the hospital.)

2. OPEN THE AIRWAY AND CHECK FOR BREATHING (3-5 SECONDS)

If you are certain the child has not suffered a spinal injury, place your hand on the child's forehead and gently tilt the head slightly backward.

Augment the head tilt by placing 1 or 2 fingers from the other hand under the chin and gently lifting upward (see figure 13.13). If you are not sure whether the child is breathing, while maintaining an open airway place your ear near the child's mouth and listen for breathing, look at the chest and abdomen for movement, and feel for air flow from the mouth. If the victim is breathing, maintain the airway; if no breathing is detected, CPR must proceed.

3. BREATHE FOR THE VICTIM (3-5 SECONDS)

While continuing to maintain an open airway, take a breath in, then hold it, open your mouth, and seal it over the mouth of the victim.

Remember that an infant will need much less air than a larger child. A proper amount of air will move the chest up and down between breaths. A slow, deliberate delivery will reduce the likelihood of forcing air into the stomach, causing distention.

Rescue breathing is the single most important maneuver in rescuing a nonbreathing child or infant. If repeated rescue breathing attempts do not result in airflow into the lungs, evidenced by chest movement, a foreign body obstruction should be suspected.

4. CHECK FOR PULSE (5-10 SECONDS)

In children over 1 year the heartbeat can be felt at the side of the neck. While maintaining the head tilt with one hand, find the windpipe at the level of the Adam's apple with two fingers of the other hand. Slide the fingers into the groove between the windpipe and neck muscles, as for adults. If no pulse is felt, proceed with chest compression and rescue breathing as below.

If a pulse is felt but there is no breathing, initiate and continue rescue breathing 15 times a minute for a child.

5. CALL EMERGENCY

If someone is available to help, have him call as soon as possible. If you are alone, complete 4 cycles of rescue breathing, or of breathing and chest compression, before taking time to call for help.

6. CHEST COMPRESSIONS

The child must be on her back on a firm surface such as the floor.

If the child is over 1 year of age, compression is applied to the breastbone by the heel of one hand, located in the midline, 2 fingers'-breadth above the tip of the breastbone. With one hand, the chest is compressed to a depth of 1 to 1 1/2 inches at a rate of 80 to 100 compressions per minute, as for an adult. Compression and relaxation time should be equal and the rhythm smooth and even. The fingers must be kept off the chest.

External compression should be accompanied by rescue breathing in a 5:1 ratio of compressions to ventilation breaths for an infant or child. Continue compression and rescue breathing until the child revives, help arrives, or you become too exhausted to continue.

While the 5:1 ratio has been used in the U.S. for decades "because oxygen is more important for children," a March 2002 study by Norwegian Air Ambulance recommends that children and infants receive the same 15:2 ratio as adults, because the 5:1 approach provides exactly the same number of breaths per minute in actual practice, but fewer chest compressions, as a substantial amount of time is lost due to switching positions.

CPR for infants

Infants under twelve months of age have significantly higher pulse and respiration rates than adults. CPR must be modified significantly to account for the differences.

Tilting the head and lifting the chin will not work in infants, as they have little or no neck. The infant should be cradled in the dominant arm, with the head resting in the rescuer's palm. As in children, the compression/respiration ratio should be 5:1, not 15:2 as in adults. Respirations are easiest if performed with the mouth covering the entire nose and mouth, given in short puffs of air and not full exhalations. Chest compressions must be swiftly performed, with two fingers bearing down on the sternum at the nipple line (where a line between the two nipples meets the sternum, halfway between both), or about one inch (one finger breadth) closer to the infant's feet for better compression volume.

Note

Continue CPR until help arrives or your life is placed in danger by continuing to perform CPR.

See also wilderness first aid for situations where it may be impossible to continue CPR and guidelines for how to proceed in such a situation.

Also note that it may be inappropriate to perform CPR in a disaster or triage situation with mass casualties.

CPR Training

CPR training is available through the American Red Cross as well as many other volunteer and governmental organizations worldwide.

External link: http://cpmcnet.columbia.edu/texts/guide/hmg13_0001.html

See also

• Mechanical ventilation
• First aid
• wilderness first aid