Cardiac arrest

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 immediately lose consciousness and stop breathing.

Diagnosis

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

Related Topics:
Unconscious - Pulse

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

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

Related Topics:
ECG

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

• asystole (known colloquially as a flatline),
• ventricular fibrillation,
• ventricular tachycardia
• severe bradycardia,
• complete heart block with a slow ventricular escape rate,
• agonal rhythm,
• or even normal electrical activity (pulseless electrical activity, formerly called electromechanical dissociation).

Potentially treatable causes of pulseless electrical activity and some other arrhythmias include:

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

• cardiac tamponade
• tension pneumothorax
• toxins or drug overdoses
• thromboembolism or other mechanical obstruction
• lack of oxygen (hypoxia)
• potassium disturbance (hypokalemia or hyperkalemia)
• hypocalcaemia
• acidaemia
• decreased blood volume (hypovolemia) due to haemorrhage or dehydration
• hypothermia