What Are the Effects of Atropine on the Heart?

Atropine test is one of the commonly used methods to identify sick sinus node syndrome (Sicksinus-syndrome, SSS). This method is simple, safe and widely used in clinical practice. First, the electrocardiogram was traced as a control, and then atropine 1.5-2 mg was injected intravenously. Immediately after injection, lead II electrocardiograms were taken at 1, 2, 3, 5, 10, 15, 20 minutes.

Atropine test

Atropine test is identification

Used for

Use with caution in patients with glaucoma or markedly enlarged prostate.

Atropine test

Different doses of atropine have different effects on the heart. Low-dose atropine excites the vagus nerve, slows sinus heart rate, reduces P waves, and presents borderline escape beats or borderline escape beat rhythms, and T waves increase. High-dose atropine can relieve the vagus nerve's inhibitory effect on the heart, make sinus frequency faster, P wave increased, T wave reduced, and other ECG changes.

I. Mechanism

Eliminate vagus nerve pairs

1.Aided diagnosis

When the dosage exceeds 5mg, poisoning occurs, but there are not many deaths, because the poisoning amount (5-10mg) and the lethal amount (80-130mg) are far away. Emergency oral atropine poisoning can be performed by gastric lavage and catharsis to remove unabsorbed atropine. When excitement is too strong, short-acting barbiturates or chloral hydrate can be used. Use nicosameter for respiratory depression. In addition, 0.5 to 1 mg of neostigmine can be injected subcutaneously every 15 minutes until the pupils are narrowed and the symptoms are relieved.

Atropine is an anticholinergic. Symptoms of atropine poisoning include dry mouth, flushed skin, elevated body temperature, shortness of breath, increased heart rate, dilated pupils, blurred vision, restlessness, delirium, and mania, etc. The main symptoms are central excitement symptoms, and in turn, they are suppressed and appear Coma and even died of breathing paralysis.

Atropine poisoning can be treated with neostigmine or pilocarpine as a antagonist. Neostigmine has a pseudocholine effect, which can slow heart rate and increase glandular secretion. The dosage is 0.02 mg / (kg · times). It is administered once every 15 to 20 minutes until the dry mouth disappears. Pilocarpine is a post-holiday pseudocholine drug, which can increase glandular secretion. For severe atropine poisoning, use 5-10mg / time, 15-30 minutes once, until the mouth is wet. In the application of the above two drugs, do not overdo it, especially for the elderly and those with heart failure, to prevent arrhythmia. Glaucoma should not be used. In the rescue of atropine poisoning, it is necessary to consider that the effect of neostigmine and pilocarpine on the blood-brain barrier is not ideal. Special attention should be paid to central nervous excitement and sedation in a timely manner. At the same time, we should also pay attention to the excessive dosage of neostigmine and cause central nervous system symptoms of the drug. It is paralysis after first excitement, but can die due to respiratory paralysis. If pilocarpine is used too much, there may be headache, dizziness, and neurological disorders when nicotine-like effects and central nervous system symptoms occur, which should be distinguished from the central nervous system excitatory symptoms of atropine poisoning.