What is Electroconvulsive Therapy (ECT)?

What is Electroconvulsive Therapy (ECT)?

Electroconvulsive therapy (ECT) is a medical procedure that delivers controlled electrical stimulation to the brain under general anesthesia to induce a generalized seizure for the treatment of severe psychiatric disorders, most notably treatment-resistant depression, bipolar depression, mania, catatonia, and schizophrenia. 1

Core Mechanism

ECT works by inducing therapeutic neuroplastic changes in limbic brain structures, particularly the hippocampus and amygdala, which are directly implicated in depression pathophysiology. 2 The electrical stimulation produces measurable volume increases in these structures that correlate with clinical improvement. 2

The Procedure

Pre-Treatment Requirements

• General anesthesia is administered by qualified personnel, typically using methohexital as the anesthetic agent. 3
• Muscle relaxation is achieved with succinylcholine to prevent injury during the induced seizure. 3, 4
• Anticholinergic medication (atropine or glycopyrrolate) may be given to protect against vagally-induced bradycardia, though this is not universally required. 3
• Patients must fast overnight before treatment. 3

Treatment Administration

• Electrode placement can be either unilateral (to the non-dominant hemisphere) or bilateral, with unilateral being preferred to minimize cognitive side effects. 3, 5
• Brief pulse stimulation is used rather than sine wave to reduce cognitive impact. 5
• Treatment frequency is typically 2-3 times weekly. 3
• The goal is to induce a seizure lasting 30-90 seconds for optimal efficacy. 5

Efficacy and Clinical Use

ECT should be regarded as an acute phase intervention only—it effectively treats the current episode but does not prevent future relapse. 3 Therefore, maintenance pharmacotherapy or other continuation treatment must be initiated after completing ECT. 3

Adverse Effects

Common and Self-Limiting

• Headache, nausea, vomiting, muscle aches typically resolve within the day of treatment and are managed conservatively (e.g., acetaminophen for headaches). 3, 5
• Confusion and agitation usually clear within an hour after awakening. 3

Cognitive Effects

• Memory impairment is the most significant concern, typically involving retrograde amnesia extending back approximately 6 months and impaired new learning for about 2 months after treatment. 3
• Most cognitive functions return to baseline within several months after completing ECT. 3, 6
• Executive function may actually improve beyond baseline levels due to prefrontal circuit modifications. 2

Serious but Rare Complications

• Prolonged seizures (>180 seconds) occur in 0-10% of treatments and require termination with additional methohexital, diazepam, or lorazepam. 3, 5
• Tardive seizures (late-onset seizures occurring 6-48 hours after treatment) are rare but require 24-48 hours of monitoring after each session. 3, 5
• Mortality risk is extremely low: 0.2 per 10,000 treatments overall, with anesthesia-related mortality at 1.1 per 10,000. 3

Critical Monitoring Requirements

• During treatment: seizure duration, airway patency, vital signs, and adverse effects must be continuously monitored. 3
• Post-treatment: patients require 1-2 hours of recovery in a designated area with skilled nursing care. 3
• Extended monitoring: surveillance for tardive seizures for 24-48 hours after each session is mandatory. 3, 5
• Neurological consultation is required if recurrent prolonged seizures or tardive seizures occur. 3

Important Clinical Caveats

Concurrent medications should be minimized whenever possible during ECT, as certain psychotropic medications can interfere with treatment. 3 The severity of symptoms requiring ECT necessitates inpatient placement for proper monitoring and safety. 3