The role of atropine in electroconvulsive therapy

Effect of Atropine Premedication on Cardiac Autonomic Function During Electroconvulsive Therapy: A Randomized Crossover Study

OBJECTIVES

Electroconvulsive therapy (ECT) results in significant cardiovascular changes. The acute cardiac autonomic changes during ECT remain unexplored. The primary objective of this study was to compare autonomic dysfunction with and without atropine premedication during ECT and secondarily to evaluate dysautonomia across psychiatric diagnoses before and after ECT.

METHODS

In this crossover study, 41 psychiatric patients were monitored during 82 ECT sessions. Patients were randomized either to receive atropine or not to receive atropine during their second ECT session and were crossed over during their third session. Heart rate, blood pressure, and oxygen saturation were continuously monitored from stimulus application until 300 seconds after ECT. Demographic characteristics and ANSiscope indices derived pre- and post-ECT were collected.

RESULTS

Autonomic dysfunction (%) before ECT was similar between atropine and no-atropine sessions (32.4 ± 15.7 vs 32.8 ± 16.7; 95% confidence interval, -7.6 to 6.7; P = 0.90) but increased significantly after ECT to 60.9 ± 16.3 and to 47.0 ± 17.3, respectively, and this difference was significant (95% confidence interval, 6.5-21.3; P < 0.001). There was no difference in the autonomic function across psychiatric diagnoses both before (P = 0.07) and after ECT (P = 0.12).

CONCLUSIONS

Cardiac autonomic dysfunction worsens after ECT in patients with psychiatric illnesses and to a significantly greater extent with atropine premedication. The degree of dysautonomia is similar across various psychiatric diagnoses both before and after ECT. Atropine premedication during ECT should be restricted to select patients susceptible to bradyarrhythmia and could be avoided in others.

Modification of tonic-clonic convulsions by atracurium in multiple-monitored electroconvulsive therapy

STUDY OBJECTIVE

To determine the effect of two different doses of atracurium on the modification of tonic-clonic convulsions in multiple-monitored electroconvulsive therapy (MMECT). To compare recovery time and adverse reactions of these doses.

DESIGN

Clinical study. Anesthesiologist was blinded in the evaluation of post-electroconvulsive therapy (ECT) myalgia and other side effects.

SETTING

University-affiliated veterans general hospital.

PATIENTS

Two groups of twelve psychiatric inpatients who suffered from major depression or catatonic-type schizophrenia that failed to respond to tricyclic antidepressant therapy.

INTERVENTIONS

Under single-channel, prefrontal electroencephalographic (EEG) monitoring, patients were given either 0.3 mg/kg or 0.5 mg/kg of atracurium intravenously (IV) after anesthetic induction with methohexital 1 mg/kg i.v.

MEASUREMENTS AND MAIN RESULTS

Evoked electromyographic responses of the adductor pollicis muscle was obtained by train-of-four stimulation of the ulnar nerve at the wrist every 20 seconds. The first twitch depression (T1) of neuromuscular blockade was maintained within 11% to 25% (atracurium 0.3 mg/kg) or 0% to 10% (atracurium 0.5 mg/kg) of control during the entire session of MMECT. Patients pretreated with atracurium 0.5 mg/kg had significantly fewer ECT-induced moderate and vigorous convulsions when compared with patients receiving atracurium 0.3 mg/kg (16.7% vs. 78.4%, moderate; 0% vs. 8.3%, vigorous). However, patients pretreated with atracurium 0.5 mg/kg took a longer time to attain a T4 ratio of 0.5 than did patients receiving atracurium 0.3 mg/kg (9.2 +/- 0.8 minutes vs. 4.3 +/- 0.4 minutes). There was no significant difference between the two groups with respect to cumulative seizure duration or frequency of bradycardia, sialorrhea, postseizure myalgia, nausea, headache, or confusion. No patient in either group recalled any event concerning electroconvulsive shock.

CONCLUSIONS

Whereas full neuromuscular blockade by atracurium 0.5 mg/kg i.v. is very effective in the modification of tonic-clonic convulsions induced by ECT, we suggest that a lower dose of atracurium (0.3 mg/kg i.v.) be used if one needs to ascertain the occurrence of ECT-induced seizures as indicated by minimum peripheral muscle activity at the time of EEG recording during MMECT.

Electroconvulsive therapy--induced hemodynamic changes unmask unsuspected coronary artery disease

Electroconvulsive therapy (ECT) is known to produce increases in heart rate and blood pressure during seizure activity due to sympathetic stimulation and systemic catecholamine surges. These intense, brief hemodynamic changes can adversely affect myocardial oxygen supply and demand. In patients with compromised myocardial circulation, ECT can unmask undiagnosed cardiac disease. In this case report, ECT was performed on a 64-year-old white male with negative cardiac history. The patient awakened complaining of chest pain and ST wave depression was noted on the electrocardiogram. Cardiology consultation and cardiac catheterization were followed by coronary artery bypass surgery for significant coronary artery stenosis prior to resumption of ECT treatments. The physiological changes that occur during ECT are discussed, as well as pitfalls in evaluation of these patients for ECT treatment.

Oxygen saturation during electroconvulsive therapy

Oxygen saturation was measured during anaesthesia and electroconvulsive therapy (ECT) using ear oximetry. Significant hypoxia occurred during some treatments; desaturation related to the number of ventilations performed after muscle relaxation and prior to the shock. Desaturation did not correlate significantly with seizure duration. These findings highlight the need for adequate oxygenation during ECT.