Cardiopulmonary arrest

From Wikipedia, the free encyclopedia

Cardiopulmonary arrest refers to the combination of cardiac arrest and respiratory arrest, each detailed below:

Respiratory arrest is the cessation of the normal tidal flow of the lungs due to paralysis of the diaphragm, collapse of the lung or any number of respiratory failures. It is a medical emergency and it usually is related to or coincides with a cardiac arrest. Respiratory arrest is first treated with Artificial respiration until the patient is revived or advanced life care arrives.

A cardiac arrest is the cessation of normal circulation of the blood due to failure of the ventricles of the heart to contract effectively during systole. The resulting lack of blood supply results in cell death from oxygen starvation. Cerebral hypoxia, or lack of oxygen supply to the brain, causes victims to lose consciousness and stop breathing.

Cardiac arrest is a medical emergency that, if left untreated, invariably leads to death within seconds to minutes. The primary first-aid treatment for cardiac arrest is cardiopulmonary resuscitation.

Etiology

Coronary artery disease (CAD) is the predominant disease process associated with sudden cardiac death in the United States. The incidence of CAD in individuals who suffer sudden cardiac death is between 64 and 90%. Other causes of cardiac arrest include electrocution and near-drowning, as well as other cardiac conditions such as the cardiomyopathies.

In children, cardiac arrest is typically caused by hypoxia from other causes such as near-drowning. With prompt treatment survival rates are high.

Every fatal injury or illness ultimately terminates in cardiac arrest, which is a natural part of the processes of death.

Treatable causes

The potentially treatable causes of cardiac arrest (4 Ts and 4 Hs) are:

Cardiac Tamponade
Tension pneumothorax
Toxins or drug overdoses
Pulmonary Thromboembolism (or other mechanical obstruction to cardiac outflow)
Hypoxia (lack of oxygen)
Electrolyte disturbances (such as hypokalemia, hyperkalemia, and hypocalcaemia)
Hypovolemia (decreased blood volume) due to haemorrhage or dehydration
Hypothermia

Diagnosis

The state of cardiac arrest is diagnosed in an unconscious (unresponsive to vigorous stimulation) person who does not have a pulse.

An ECG clarifies the exact diagnosis and guides treatment. but treatment should begin without awaiting an ECG. The ECG may reveal:

asystole (known colloquially as a flatline)
pulseless electrical activity (formerly called electromechanical dissociation)

ventricular fibrillation
ventricular tachycardia
severe bradycardia
complete heart block with a slow ventricular escape rate
agonal rhythm

Treatment

First aid

Seconds count. Call for help immediately or send someone for help. Begin cardiopulmonary resuscitation (CPR) immediately. CPR only buys time for help to arrive but does not restart the heart. If an automated external defibrillator is available, use it immediately.

Field care

Appropriately trained personnel apply advanced cardiac life support protocols as soon as they arrive, unless there is a valid do not resuscitate order or advance health directive. If so, it is ethically appropriate to permit natural death to occur in accordance with the wishes of the patient.

Do not use an AED unless you hold current qualifications to do so. The incorrect usage can lead to more harm than good. Also legally you will be held accountable.

Hospital treatment

In many hospitals, cardiac arrest results in one of the carers announcing a "Code Blue"(or the local equivalent) for immediate response by a trained team of nurses and doctors. The resuscitating team continues advanced cardiac life support until the patient recovers or a doctor declares the patient's death.

Ethical Issues

Cardiopulmonary resuscitation and advanced cardiac life support are not always in a person's best interest. This is particularly true in the case of terminal illnesses when resuscitation will not alter the outcome of the disease. Properly performed CPR often fractures the rib cage, especially in older patients or those suffering from osteoporosis. Defibrillation, especially repeated several times as called for by ACLS protocols, may also cause electrical burns. Internal cardiac massage, an ACLS procedure performed by emergency medicine physicians requires splitting open the rib cage, which is painful during the weeks of recovery. While such treatment is worthwhile when it saves a life, it is undignified and simply adds to the suffering of a victim with a terminal illness who wishes to die peacefully.

It is not surprising that some people with a terminal illness choose to avoid such "heroic" measures and die peacefully.

People with views on the treatment they wish to receive in the event of a cardiac arrest should discuss these views with both their doctor and with their family.

It is also important that these views are written down somewhere in the medical record. In the event of cardiac arrest, health professionals need to act quickly on the information that is available to them. As cardiac arrest often happens out of regular hours, the resuscitation team rarely includes anybody who actually knows the patient.

A patient may ask their doctor to record a do not resuscitate (DNR) order in the medical record. Alternatively, in many jurisdictions, a person may formally state their wishes in an "advance directive" or "advance health directive".