Electroconvulsive therapy

Two variations of electroconvulsive therapy exist depending on the placement of electrodes and the direction of electrical current applied:

• Bilateral electroconvulsive therapy: The electrodes between which the electrical current flows are placed from temple to temple on the patient’s head; therefore, the charge is delivered to both hemispheres of the brain. The current spreads throughout the entire brain and affects both halves equally.
• Unilateral electroconvulsive therapy: In this type of electroconvulsive therapy, the two electrodes are placed such that the current is delivered only to one side of the brain (typically the right hemisphere). One electrode is placed at the very top of the head (the vertex) and the other is placed in the temple of the side receiving the charge (typically the right temple). It has been noted that memory loss complications are more pronounced with the application of electrical current on the dominant hemisphere, which is commonly the left hemisphere that controls the right side of the body. Unilateral treatment typically requires a larger dose of electroconvulsive therapy.

Electroconvulsive therapy can be a very useful treatment modality to rapidly reverse psychiatric symptoms in patients who have not responded to drug-based treatments or psychotherapy. However, given the distressing nature and associated complications, electroconvulsive therapy should be used sparingly and be reserved for certain conditions. Electroconvulsive therapy can be considered in the following cases:

• Severe depressive illness or refractory depression: In major depressive disorders, severe escalations with symptoms of delusions, hallucinations or homicidal or suicidal tendencies require treatment with electroconvulsive therapy. ECT has been noted to be more efficacious than antidepressant drug treatment for short-term management in such cases. The most effective treatment of major depressive disorder is electroconvulsive therapy.
• Catatonia: Catatonia is a psychiatric disorder in which the patient is unable to move or communicate normally. They may either become unable to move or move excessively and abnormally. Additionally, they can become confused and/or agitated. Catatonia can appear with schizophrenia or mood disorders (like depressive or manic disorders). While catatonia is usually treated with benzodiazepines, sometimes the use of electroconvulsive therapy becomes necessary on drug treatment failure. There is no evidence of ECT being superior to drug treatment and is reserved as a last resort measure.
• A prolonged or severe episode of mania: Mania is a mood disorder in which the patient is unreasonably euphoric, excited, hyperactive and, at times, delusional. During a manic episode of elevated mood and increased energy, the patient can sometimes become dangerous to themselves and others. The mainstay of treatment of a manic episode is the use of antipsychotic medicines, but electroconvulsive therapy can be tried if the symptoms are uncontrolled as last-line treatment.
• Manic episodes of bipolar mood disorder: Bipolar disorder can present either with episodes of depression, mania or hypomania (a less severe form of mania) depending on the type of the bipolar disorder. In varieties with prolonged or severe manic episodes, management may include electroconvulsive therapy if the patient is unresponsive to other treatment options.
• Schizophrenia: The usefulness of electroconvulsive therapy in the treatment of schizophrenia is debatable but is still used at times. In cases where no other treatment option has worked, ECT may be tried after careful deliberation by the medical team and with the informed consent of the patient or their family.

Furthermore, given the intrusive nature of electroconvulsive therapy, it is imperative to proceed with therapy only if:

• The patient gives consent: If the patient possesses the mental capacity to make decisions, it is necessary to take their consent.
• Consent of caretakers or family: In case the patient is unable to make decisions for themselves, the consent of the next of kin or an individual assigned to make decisions for the patient must be taken.
• Decisions must be taken keeping the best interest of the patient in mind.

Electroconvulsive therapy must be used sparingly for a limited period of time and should be stopped when, or if:

• Desired effect or alleviation of psychiatric symptoms is achieved
• Side effects of electroconvulsive therapy develop
• The patient refuses further treatment with electroconvulsive therapy

(Read more: Mental Health)

The doctor begins by making a thorough assessment of the patient with a medical history, physical examination, psychiatric evaluation, cognitive assessment and some laboratory tests and radiological imaging if necessary. Hand dominance (right-handedness or left-handedness) is noted and electroconvulsive therapy is ideally applied on the non-dominant brain hemisphere. For example, right-sided electrode placement is preferred in unilateral electroconvulsive therapy for a right-handed person, as the left side of the brain controls the right half of the body. Informed consent is taken from the patient (if in the mental capacity to take decisions) or from the next of kin where necessary. Certain measures need to be taken before an electroconvulsive therapy session:

• The patients are advised to remain nil per oral (not eat or drink starting from midnight before the session till afterwards) due to possible complications with general anaesthesia.
• Smokers must not smoke on the morning of the treatment session.

(Read more: How to quit smoking)

Following the decision to institute electroconvulsive therapy (ECT) after due trial of alternative treatment options, informed consent of the patient or next of kin and a thorough assessment of the patient, a session is scheduled. The patient is administered general anaesthesia to be sedated and put under as well as a muscle relaxant to prevent any possible muscle convulsions. Depending on the type of electroconvulsive therapy (ECT) to be administered, bilateral or unilateral, the electrodes are placed either on both the temples or on the top of the head and on one temple (generally the right one), respectively. The dose of the electroconvulsive therapy (ECT) to be delivered is calculated in terms of the current, charge, duration, pulses per second and any other necessary parameters. The current is delivered as a brief pulse or an ultra-brief pulse to induce a seizure (without muscular convulsions), lasting no longer than 60 seconds, in the patient’s brain. The patient’s vitals (including heart rhythm) are monitored throughout the session. After the effect of the general anaesthesia weans, the patients are allowed to go home on the same day.

Typically, 6 to 12 sessions are carried out, generally on a twice a week schedule. Treatment is stopped if the patient responds, develops symptoms or refuses any further sessions. Although electroconvulsive therapy (ECT) is used on a short-term basis, rarely maintenance sessions, once per month, are carried out.

In the presence of certain factors, electroconvulsive therapy should either be reconsidered or carried out after making suitable adjustments and taking adequate precautions. Following are some relative contraindications to ECT:

• Elevated intracranial pressure
• Space occupying lesion
• Recent myocardial infarction (within the last 3 months)
• Severe arterial hypertension
• Narcotic intolerance
• Acute glaucoma
• Abnormalities in brain (cerebral) arteries, e.g., aneurysm, angioma
• Pregnancy: Although used as the very last reserve treatment for depressive disorders in pregnancy, electroconvulsive therapy brings with it an unnecessary risk to the mother and fetus and many doctors choose to avoid it. However, due to lack of evidence, the risk has not been assessed and some may choose to treat problematic refractory maternal depression with electroconvulsive therapy if the benefits outweigh the possible adverse effects.

Although considered relatively safe, some complications and side effects can arise after a session of electroconvulsive therapy, either immediately following it or in the long run.

• Immediate complications: Some side effects that can arise following the delivery of electroconvulsive therapy (ECT) include, but may not be limited to: 
  • Headache 
  • Nausea 
  • Cardiovascular instability - eg, arrhythmias and hypotension
  • Status epilepticus
  • Related to the general anaesthetic
  • Laryngospasm
  • Peripheral nerve palsies
  • Temporary, short-term functional disorders such as amnesic aphasia
  • Prolonged seizures
• Long-term complications: Although electroconvulsive therapy is generally intended for short term rapid improvement of psychiatric conditions not responding to traditional drug-based or psychotherapy treatments, its use can sometimes bring about long-term complications. It is thus vital to ensure the use of the therapy is judicious. Some long-term complications following electroconvulsive therapy include, but may not be limited to: 
  • Anterograde amnesia: The ability to form new memories or make new learnings after electroconvulsive therapy can be impaired. While the complication is more pronounced with the use of bilateral electroconvulsive therapy over unilateral treatment, if both electrodes are placed in the dominant half of the brain with unilateral electroconvulsive therapy, the effect can be just as bad. 
  • Retrograde amnesia: Information and memories accrued before electroconvulsive therapy (ECT) can become hard to recall. The memory deficit is greater in the case of bilateral as opposed to unilateral electroconvulsive therapy (ECT) or if both electrodes are placed on the dominant side of the brain with unilateral therapy. 
  • Memory changes: Changes to a patient’s memories can be quite marked with an increasing number of electroconvulsive therapy sessions and the type of electrical stimulus delivered. The distress caused by the memory alteration caused to the patient can be severe enough to counter the intended benefits of electroconvulsive therapy. Brain imaging typically remains normal in the presence of memory loss or changes and the exact cause of the complication cannot usually be pinpointed.

While electroconvulsive therapy can be fatal, the mortality rate is similar to that of the use of general anaesthesia in surgery. With careful administration to the right candidates, electroconvulsive therapy (ECT) proves to be a beneficial mode of psychiatric treatment.