Asystole

Asystole - cardiac arrest, accompanied by the disappearance of its electrical activity.

[1], [2], [3], [4], [5]

What causes asystole?

• Operations with increased stimulation of the vagus nerve (eg, gynecological / ophthalmic).
• The initially available complete heart block, blockade of the second degree or trifascicular.

How is it manifested asystole?

• Electrical activity on the ECG is absent - as a rule, on the monitor slowly undulating isolines.
• Pulse on the main arteries (carotid and femoral) is not palpable.
• Sometimes the electrical activity of the atria is retained in the absence of electrical activity of the ventricles. This "asystole with a P wave" can respond to electrocardiostimulation.

How is the asystole recognized?

Electrolytes and urea, blood gases, chest X-ray, ECG.

Differential diagnosis

• Disconnecting the ECG electrode - while on the monitor will be a straight line.
• Very low voltage ECG - while on the monitor, some signs of electrical systems are usually saved.
• Hypoxia - obstruction of the respiratory tract, intubation of the esophagus or bronchus, stopping oxygen supply.
• Hypovolemia is a hemorrhagic shock (especially when anesthesia is induced), anaphylaxis.
• Hypo / hyperkalemia and metabolic disorders - renal failure, suxamethonium-induced hyperkalemia in burns.
• Hypothermia is unlikely.
• Stressed pneumothorax - especially in patients with trauma or after central venous catheterization.
• Cardiac tamponade - after penetrating trauma.
• Intoxication / therapeutic disorders - after drug overdose (self-inflicted or iatrogenic).
• Thromboembolism is a massive thrombus in the pulmonary artery.

[6]

What should I do if there is an asystole?

• Stop any surgical manipulations that can cause excessive stimulation of the vagus nerve (eg, peritoneal tract).
• Restore airway patency, start ventilation with 100% oxygen. Intubate - but this should not delay the onset of an indirect heart massage.
• Conduct an indirect cardiac massage with a frequency of 100 per min, without interrupting it for ventilation.
• Introduce atropine intravenously - according to the universal algorithm of expanded resuscitation once in a dose of 3 mg. If the asystole was caused by the stimulation of the vagus during surgical intervention, it is more expedient to administer atropine fractional by 0.5 mg.
• If asystole is not permitted after stopping surgical procedures or injecting atropine, inject 1 mg of epinephrine. Repeat this dose of epinephrine every 3 minutes until the recovery of spontaneous circulation.

Further management

• Eliminate or treat potentially reversible causes of asystole.
• Fast fluid infusion (including blood during severe blood loss).
• Complete cardiac blockade or blockade of the second degree of Mobitz type II require the use of pacing. Before the arrival of trained personnel with experience in transvenous pacemaking, it can be performed percutaneously.
• If resuscitation is successful, complete the life-saving part of the operation (for example, stop bleeding). Except when the cardiopulmonary resuscitation was very short (say, less than 3 minutes), the patient should be left intubated and transferred to the ICU.
• Perform a chest X-ray, an ECG in 12 leads, an analysis of blood gases and plasma electrolytes.

Pediatric features

• With asystole in children, resuscitation is built on the same principles.
• Hypoxia is more likely as a root cause.

Special Considerations

• Asystole, associated with excessive stimulation of the vagus nerve or the administration of suxamethonium, is resolved, as a rule, spontaneously after elimination of the cause that caused it. Nevertheless, atropine (0.5-1 mg) or glycopyrrhalate (200-500 μg) should be administered, and sometimes a short, indirect heart massage may be required.
• In such cases, subsequent studies are usually not needed.
• In other cases, the prognosis is unfavorable, except for asystalia, caused by a potentially reversible cause of immediate intervention.