Morgagni-Adams-Stokes Syndrome

Morgagni-Adams-Stokes Syndrome (MAC) is a syncopal condition developing against a background of asystole, followed by the development of acute cerebral ischemia. Most often it develops in children with atrioventricular blockade of II-III degree and syndrome of weakness of the sinus node with a ventricular contraction rate of less than 70-60 per minute in young children and 45-50 in older children.

Bradycardia and bradyarrhythmia lead to a syndrome of small cardiac output, if the heart rate is less than 70% of the age norm. Normally, the lower limit of heart rate per minute for awake children over 5 years is 60, under 5 years - 80; for children of the first year of life - 100, the first week of life - 95. During sleep, these limits are lower: less than 50 per minute in children older than 5 years and less than 60 for young children.

Children have the most frequent and dangerous, but relatively favorable response to treatment conduction disorders - sinus bradycardia, due to the increased tone of the vagus nerve in the background of hypoxia.

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

Symptoms of Morgagni-Adams-Stokes syndrome

The child suddenly turns pale, loses consciousness, breathing becomes rare and convulsive, followed by its arrest and increasing cyanosis. Pulse and blood pressure are not determined, heart rate is 30-40 per minute. Possible the development of seizures, involuntary urination and defecation.

The duration of the attack can range from a few seconds to several minutes. More often the attack passes independently or after corresponding medical actions, but the lethal outcome is possible.

Treatment of Morgagni-Adams-Stokes syndrome

Treatment of hypoxemia in combination with one-, two-fold administration of age-related doses of atropine intravenously or in the muscles of the bottom of the mouth, as a rule, quickly leads to a restoration of the heart rate. More active treatment requires bradycardia, which arose against a background of various poisonings (poisons of some fly agarics, organophosphorus substances, beta-blockers, opiates, barbiturates, calcium channel blockers). In these cases, the dose of atropine is increased 5-10 times and the infusion of isoprenaline is carried out.

Emergency care for recurrences of the asystolic form of MAC attacks begins with a precordial stroke (in children of an early age it is not recommended to apply), then intravenously inject 0.1% atropine solution from the calculation of 10-15 μg / kg or 0.5% isoprenaline solution in a dose from 0.1-1 μg / kghmin) to 3-4 μg / kghmin), and at the older age - 2-10 μg / kghmin). Atropine can be re-injected every 3-5 minutes (depending on the effect) to achieve a total dose of 40 mcg / kg (0.04 mg / kg). With insufficient effectiveness of drug treatment, transesophageal, external percutaneous or intravenous electrostimulation of the heart is performed under electrocardiographic control.

In children's practice, 0.1% solution of epinephrine in a dose of 10 mcg / kg is rarely used, as with severe conduction disorders there is a risk of developing ventricular fibrillation. Epinephrine is injected intravenously in the initial treatment of ventricular fibrillation or ventricular tachycardia without pulse, followed by defibrillation with a charge energy of 360 J. The introduction of epinephrine can be repeated every 3-5 minutes. The drug is also used in the presence of electrical activity of the heart without pulse and asystole. With symptomatic bradycardia, not sensitive to atropine and percutaneous electrocardiostimulation, epinephrine is administered intravenously drip from the calculation of 0.05-1 μg / kghmin).

The most appropriate for the prevention of cardiac arrest with severe hyperkalemia is intravenously slowly injected 10% calcium chloride solution at a dose of 15-20 mg / kg. If ineffectiveness is introduced again after 5 minutes. After applying the drug, sodium hydrogencarbonate can not be administered, since it increases the content of non-ionized calcium. Effective action of calcium chloride lasts for 20-30 minutes, so it is necessary to infuse a 20% dextrose solution (4 ml / kg) with insulin (1 ED per 5-10 g of dextrose) to increase the rate of potassium entry into the cells.

It is important to take into account that calcium preparations in children increase the toxic effect of cardiac glycosides on the myocardium, and therefore it is necessary to observe great care when they are prescribed. In case of cardiac glycosides intoxication, it is advisable to administer a 25% solution of magnesium sulfate in a dose of 0.2 ml / kg and a 5% solution of dimercaprol at a rate of 5 mg / kg. To increase the excretion of potassium, it is necessary to introduce furosemide in a dose of 1-3 mg / kghsut). To remove potassium, cation exchange resins are also used (sodium polystyrene sulfonate, kaexylate is prescribed at 0.5 g / kg in 30-50 ml of 20% sorbitol solution inside or 1 g / kg in 100-200 ml 20% dextrose solution in the rectum. The most effective means of reducing the level of potassium in the serum is hemodialysis.