Abstract
Anesthesia for electroconvulsive therapy (ECT) is generally seen as a straightforward procedure with a low risk of serious complications. While this is true in the main, there can still be a range of predictable, although usually minor, physiologic disturbances related to both the anesthetic and the ECT procedure itself. Because patients undergoing ECT may be older with a number of comorbidities, such effects may take on a greater significance and need to be specifically addressed
Keywords
anesthesia, complications, electroconvulsive therapy, hemodynamics, pharmacology
Case Synopsis
A 65-year-old man with a major depressive illness is scheduled to commence his first course of electroconvulsive therapy (ECT). Medical assessment before commencing treatment reveals he is otherwise well, apart from being hypertensive (serial readings in the order of 180/95). For management of his psychiatric condition he is currently taking tranylcypromine, lithium, and sodium valproate. Following anesthesia with thiopentone and suxamethonium and a period of hyperventilation, the stimulus is delivered. There was a significant motor seizure, evidenced by tonic-clonic movement of all limbs. The seizure is accompanied by a significant increase in heart rate. This falls rapidly as the seizure comes to an end. In the postanesthesia care unit, the blood pressure remains elevated for 15 minutes, slowly returning to pre-ECT levels. On emergence from anesthesia, the patient is confused and combative. Small doses of midazolam are given to help settle the patient. Eventually he wakes and is orientated to time and place. He has no memory of recent events.
When he presents for his next treatment he complains of severe widespread muscle pain.
Problem Analysis
This case demonstrates the main complications associated with ECT anesthesia: medication management, inadequate relaxation, hemodynamic changes, emergence agitation, and suxamethonium-induced myalgia.
Although anesthesia for electroconvulsive therapy (ECT) is usually a fairly straightforward process, there can still be significant complications associated with the procedure ( Tables 31.1 and 31.2 ), the risk of which can be minimized with careful management. The initial treatment session is referred to as a “titration” session, during which a number of stimuli are usually applied with the aim of establishing the threshold for eliciting a seizure in an individual patient. Such sessions are usually slightly longer than standard treatment session and can be associated with a higher incidence of adverse effects in general. The anesthetist needs to be especially vigilant during the titration session. The patient may have a number of such sessions during a course of treatment as a result of either change in electrode placement or needing to reestablish a level of stimulation during a prolonged series of treatments.
Complication | Management Options |
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Inadequate response to treatment or seizures of brief duration | Use lowest possible dose of induction agent, adding remifentanil if needed to reduce awareness. Ensure agents with anticonvulsant activity have been ceased. |
Inadequate muscle relaxation | Increase dose of suxamethonium. Wait 90 seconds after injection. Use tendon hammer to check tendon reflexes. |
Prolonged seizure | Use small dose of induction agent to terminate. Usually responds promptly. |
Changes in pulse rate and blood pressure during treatment | Changes are usually transient and interventions have not been shown to confer any particular benefit. |
Hypoxia during treatment | Ensure adequate oxygenation with hyperventilation before treatment. Minimize muscle activity (which increases oxygen consumption) during treatment. |
Complication | Management |
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Prolonged hypertension | Usually settles without treatment; otherwise glyceryl trinitrate, hydralazine, or metoprolol |
Post-ECT agitation | Restrain as appropriate; midazolam or propofol as intravenous aliquots |
Myalgia | No effective treatment; almost always settles after initial treatment |
Nausea | Standard antiemetics |