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Jai Ganesh

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Cardiopulmonary resuscitation (CPR)

Cardiopulmonary resuscitation (CPR)

Gist

Cardiopulmonary resuscitation (CPR) is a life-saving technique performed during cardiac or respiratory arrest to maintain blood flow and oxygenation to vital organs until professional medical help arrives. It involves chest compressions and rescue breaths to temporarily pump blood and oxygen to the brain and other organs. CPR is crucial in situations like cardiac arrest or when someone isn't breathing normally.

Summary

Cardiopulmonary resuscitation (CPR) consists of the use of chest compressions and artificial ventilation to maintain circulatory flow and oxygenation during cardiac arrest (see the images below). Although survival rates and neurologic outcomes are poor for patients with cardiac arrest, early appropriate resuscitation—including early defibrillation when needed—and appropriate implementation of post–cardiac arrest care lead to improved survival and neurologic outcomes.

Indications and contraindications

CPR should be performed immediately on any person who has become unconscious and is found to be pulseless.

Assessment of cardiac electrical activity via rapid rhythm strip recording can provide a more detailed analysis of the type of cardiac arrest, as well as indicate additional treatment options.

Loss of effective cardiac activity is generally due to the spontaneous initiation of a nonperfusing arrhythmia, sometimes referred to as a malignant arrhythmia. The most common nonperfusing arrhythmias include the following:

* Ventricular fibrillation (VF)
* Pulseless ventricular tachycardia (VT)
* Pulseless electrical activity (PEA)
* Asystole
* Pulseless bradycardia

Although prompt defibrillation has been shown to improve survival for VF and pulseless VT rhythms,  CPR should be started before the rhythm is identified and should be continued while the defibrillator is being applied and charged. Additionally, CPR should be resumed immediately after a defibrillatory shock until a pulsatile state is established. This is supported by studies showing that preshock pauses in CPR result in lower rates of defibrillation success and patient recovery.

In a study involving out-of-hospital cardiac arrests in Seattle, 84% of patients regained a pulse when defibrillated during VF.  Defibrillation is generally most effective the faster it is deployed.

The American College of Surgeons, the American College of Emergency Physicians, the National Association of EMS Physicians, and the American Academy of Pediatrics have issued guidelines on the withholding or termination of resuscitation in pediatric out-of-hospital traumatic cardiopulmonary arrest.  Recommendations include the following:

* Withholding resuscitation should be considered in cases of penetrating or blunt trauma victims who will obviously not survive.

* Standard resuscitation should be initiated in arrested patients who have not experienced a traumatic injury.

* Victims of lightning strikes or drowning with significant hypothermia should be resuscitated.

* Children who showed signs of life before traumatic CPR should be taken immediately to the emergency department; CPR should be performed, the airway should be managed, and intravenous or intraosseous lines should be placed en route.

* In cases in which the trauma was not witnessed, it may be assumed that a longer period of hypoxia might have occurred and limiting CPR to 30 minutes or less may be considered.

* When the circumstances or timing of the traumatic event are in doubt, resuscitation can be initiated and continued until arrival at the hospital.

* Terminating resuscitation in children should be included in state protocols.

Contraindications

The only absolute contraindication to CPR is a do-not-resuscitate (DNR) order or other advanced directive indicating a person’s desire to not be resuscitated in the event of cardiac arrest. A relative contraindication to performing CPR is if a physician justifiably believes that the intervention would be medically futile. This is an area of active research.

Details

Cardiopulmonary resuscitation (CPR) is an emergency procedure used during cardiac or respiratory arrest that involves chest compressions, often combined with artificial ventilation, to preserve brain function and maintain circulation until spontaneous breathing and heartbeat can be restored. It is recommended for those who are unresponsive with no breathing or abnormal breathing, for example, agonal respirations.

CPR involves chest compressions for adults between 5 cm (2.0 in) and 6 cm (2.4 in) deep and at a rate of at least 100 to 120 per minute. The rescuer may also provide artificial ventilation by either exhaling air into the subject's mouth or nose (mouth-to-mouth resuscitation) or using a device that pushes air into the subject's lungs (mechanical ventilation). Current recommendations emphasize early and high-quality chest compressions over artificial ventilation; a simplified CPR method involving only chest compressions is recommended for untrained rescuers. With children, however, 2015 American Heart Association guidelines indicate that doing only compressions may result in worse outcomes, because such problems in children normally arise from respiratory issues rather than from cardiac ones, given their young age. Chest compression to breathing ratios are set at 30 to 2 in adults.

CPR alone is unlikely to restart the heart. Its main purpose is to restore the 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 to restore a viable, or "perfusing", heart rhythm. Defibrillation is effective only for certain heart rhythms, namely ventricular fibrillation or pulseless ventricular tachycardia, rather than asystole or pulseless electrical activity, which usually requires the treatment of underlying conditions to restore cardiac function. Early shock, when appropriate, is recommended. CPR may succeed in inducing a heart rhythm that may be shockable. In general, CPR is continued until the person has a return of spontaneous circulation (ROSC) or is declared dead.

Medical uses

CPR is indicated for any person unresponsive with no breathing or breathing only in occasional agonal gasps, as it is most likely that they are in cardiac arrest.  If a person still has a pulse but is not breathing (respiratory arrest), artificial ventilations may be more appropriate, but due to the difficulty people have in accurately assessing the presence or absence of a pulse, CPR guidelines recommend that lay persons should not be instructed to check the pulse while giving healthcare professionals the option to check a pulse. In those with cardiac arrest due to trauma, CPR is considered futile but still recommended. Correcting the underlying cause such as a tension pneumothorax or pericardial tamponade may help.

Additional Information

CPR stands for cardiopulmonary resuscitation. It’s a way to save the life of someone who’s in cardiac arrest (when their heart can’t pump blood). It’s an attempt to restart their heart and/or keep their blood circulating.

CPR is a technique that anyone can learn. The key part of CPR is chest compressions, which keep blood flowing to vital organs until a regular heartbeat returns. Giving rescue breaths brings more oxygen into the person with cardiac arrest.

A person of any age needs CPR if ALL of the following happens:

* They collapse
* They don’t respond
* They aren’t breathing
* They don’t have a pulse

If you receive CPR immediately after you go into cardiac arrest, along with other timely emergency care, your chance of survival can double or even triple.

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