Related Experiment Video
Updated: Apr 30, 2026
Pupillary Response as Assessment of Effective Seizure Induction by Electroconvulsive Therapy
Published on: April 11, 2019
Effect of atropine dose on heart rate during electroconvulsive therapy
Zirka H Anastasian1, Nayema Khan, Eric J Heyer
1From the *Department of Anesthesiology, Columbia University, New York, NY; †Department of Anesthesiology, Beth Israel Deaconess Medical Center, Boston, MA; ‡Departments of Neurology, §Psychiatry and ∥Epidemiology, Columbia University, New York, NY.
Introduction:
Transient bradycardia during the stimulation phase of electroconvulsive therapy (ECT) is a well-known clinical observation. The optimal dose of atropine needed to prevent bradycardia has not been determined. This study was designed to investigate the effect of low doses of atropine on heart rate during ECT.
Methods:
Patients who received at least 2 different doses of atropine over their series of right unilateral ECT were included in the analysis. The anesthetic consisted of 0, 0.2, 0.3, or 0.4 mg of atropine, methohexital, and succinylcholine. Heart rate was measured by the RR interval, the time between sequential R waves on the electrocardiogram. Analysis was performed using logistic multivariate regression and repeated-measures multivariate analysis of variance.
Results:
One hundred eighteen ECT sessions were identified from 19 patients. Patients were grouped into 4 groups by atropine dose (0, 0.2, 0.3, or 0.4 mg) with 9, 33, 13, and 63 ECT sessions identified for each dose, respectively. Patients who received atropine had significantly less bradycardia after electrical stimulus and a faster heart rate through the seizure than patients who did not receive atropine. There was no significant difference in heart rate between patients receiving 0.2, 0.3, and 0.4 mg of atropine at any time point. There was no significant difference in heart rate at time points after the seizure conclusion in any group of patients.
Conclusion:
Low-dose atropine results in significantly less bradycardia after electrical stimulus. There was no significant difference in heart rate across low doses of atropine.
Related Concept Videos
01:30Electroconvulsive Therapy
01:25ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
01:25Cardiopulmonary Resuscitation IV: Pharmacological Management
01:24Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers
01:16ECG Interpretation of Arrhythmias I: Sinus Arrhythmias
Types of Arrhythmias
Sinus Node Arrhythmias
Sinus Bradycardia: Originating from the sinoatrial (SA) node, sinus bradycardia involves slower impulses, resulting in a heart rate of less than 60 beats per minute (bpm). Causes include sleep, vagal stimulation, beta-blockers, hypothyroidism,...
01:19Cardiac Output I:Effect of Heart Rate on Cardiac Output
Cardiac output (CO) refers to the total amount of blood ejected by one of the ventricles in liters per minute (L/min). In a resting adult, CO ranges from 5 to 6 L/min, adjusting according to the body's metabolic requirements.
Effect of Heart Rate on Cardiac Output
Cardiac output adapts to metabolic demands during stress, physical activity, or illness. The autonomic nervous system regulates heart rate via the sinoatrial node. The parasympathetic nervous system decreases heart...