Electroconvulsive Therapy (ECT) was introduced by Cerletti in Italy in 1938. It involves production of a fit by passing an electric current through the brain.
ECT today is carried out under a short general anaesthetic, and a muscle relaxant is given to reduce the intensity of the fit. Modern ECT machines deliver brief square-wave (not sine-wave) pulses of electricity and allow the ědoseî to be individually adjusted for the patient.
Though ECT has always tended to arouse controversy, with some pressure groups demanding a ban on its use, most psychiatrists consider it a highly effective and sometimes lifesaving treatment for certain severe mental illnesses.
However, these days it seems to be necessary to be used much less frequently. The author is responsible for a highly morbid and deprived catchment area, yet has only needed to prescribe it twice in the last 3 years. Colleagues in elderly psychiatry prescribe it more frequently.
INDICATIONS Depressive illness is the main indication. An MRC research study in 1965 showed that ECT is superior to antidepressant drugs for treating severe depression. Most depressed patients, however, are given drugs as the first-line treatment with ECT being used in the following circumstances:
- When life is threatened by suicidality.
- When life and health are threatened by refusal of food and drink.
- When antidepressant drugs have failed.
- When antidepressant drugs are contraindicated for medical reasons, such as cardiac arrhythmias.
- In the elderly, including some with cognitive impairment, when unwanted effects of medication may make drug treatment slower and riskier.
ECT is very occasionally used for inpatients with severe schizophrenia, especially catatonic schizophrenia, or mania which has not responded to intensive drug treatment. This indication is uncommon in the UK, though remains prevalent in developing countries.
MODE OF ACTION This is unknown, but may relate to alterations in neurotransmitter sensitivity. ECT causes many physiological changes, including slowing of the EEG, and increased secretion of sympathetic amines, prolactin and other pituitary hormones, but none of these correlate reliably with clinical response.
Some sceptics claim that ECT is effective because it results in confusion, which makes the patient forget depressing thoughts.
Production of an adequate fit, arbitrarily defined as a generalised tonic-clonic seizure lasting at least 25 seconds, appears to be necessary for a good clinical effect. The minimum size of electrical stimulus required to cause a fit varies a great deal between patients, and is influenced by many factors including age, medication, and previous exposure to ECT. Ideally the stimulus should be individually adjusted to be slightly above the individualís seizure threshold. If the stimulus is too low, no fit occurs; if too high, marked confusion may follow the treatment.
Medications with anticonvulsant effects such as benzodiazepines should be stopped before treatment.
Research studies comparing real ECT with ěpseudo ECTî, in which an anaesthetic and muscle relaxant are given but no electric shock, shows real ECT is more effective in the treatment of depression but ěpseudo ECTî has some clinical benefit too (
1). This suggests that factors such as the complexity and mystique of the treatment, the extra medical and nursing attention and/or the anaesthetics, are partly responsible for the therapeutic effect.
EFFICACY AND PREDICTION OF RESPONSE About 80% of severe depressive episodes respond well to ECT in the short term. Features predicting a good response- which are essentially markers of a severe depressive illness- include retardation, guilt, delusions, early morning waking, symptoms worse in the mornings, short duration of illness and stable premorbid personality.
Milder depression tends not to respond well, especially if mixed with anxiety in a patient with neurotic symptoms and poorly adjusted premorbid personality, and ECT would not now be used in this situation.
About two-thirds of patients given ECT for depression will relapse within six months, unless given maintenance treatment with an antidepressant drug or lithium.
TIMING AND NUMBER OF TREATMENTS ECT is usually given twice a week for depressive illness, and more frequent administration has no advantage.
The number of treatments required in a course of ECT varies considerably, though typically would be 6ń10. There is usually a transient improvement for a few hours after each application, which gradually becomes sustained.
Most depressive illnesses are episodes of a recurrent condition, often requiring prophylactic treatment; this is usually with medication, but very occasional patients seem to do best with ěmaintenanceî ECT administered every few weeks.
PRACTICALITIES OF TREATMENT Treatment is best carried out in a specially equipped ECT suite within a psychiatric unit. Inpatient admission is usual for the first course, but outpatient ECT is feasible for patients in good general health, who can be trusted not to eat or drink on the morning of treatment, and not to drive or cycle home immediately afterwards.
The treatment is carried out by a psychiatrist, a nurse and an anaesthetist. Physical examination must be performed before the course begins, in order to exclude the contraindications listed below.
CONTRAINDICATIONS
- Anaesthetic contraindications such as severe respiratory or cardiac disease.
- Organic brain disease of a kind in which increased cerebral blood flow would be dangerous, such as cerebral aneurysm, or conditions involving raised intracranial pressure. Other forms of organic brain disease including dementia, epilepsy and a past history of head injury do not necessarily rule out the use of ECT, but do carry an increased risk of confusion after treatment.
These contraindications are relative, not absolute, and may need to be balanced against the risk to life posed by severe depression when deciding whether ECT is justified.
Pregnancy is not a contraindication, nor is old age.
BILATERAL vs UNILATERAL ECT The electrodes may be applied to both sides of the head (bilateral ECT), which is the standard treatment, or to the non-dominant side only (unilateral ECT). Bilateral ECT produces greater memory loss and confusion, but is more effective in that fewer treatments per course are needed for a therapeutic effect. Bilateral ECT is therefore preferred when a rapid response is required, but patients prone to marked cognitive impairment may be better treated with unilateral ECT.
UNWANTED EFFECTS- Memory impairment: transient memory impairment, both retrograde and anterograde, is frequent after each application, but usually settles within a few hours. ECT as used now does not seem to cause persisting memory problems .There are a small number of chronic ex-asylum patients who may have had large numbers of treatments many years ago, and here a link to memory problems is more plausible.
- Confusion: mild transient confusion after treatment is frequent. If a severe confusional state develops, ECT should be discontinued, and evidence for organic brain disease sought.
- Anaesthetic complications.
- Fractures: not a hazard if the fit is adequately modified by a muscle relaxant.
- Mania may be precipitated when ECT is given to patients with bipolar affective disorder in the depressed phase.
Mortality is 1 per 50 000 treatments, almost always from anaesthetic complications.
CONSENT FOR ECT Most patients who have ECT do so voluntarily. (Indeed, the last two patients I have prescribed it for have actually asked for it, after long inpatient stays without improvement.)
They are required to sign a consent form before treatment. This should be preceded by a full explanation of the procedure, reinforced by an information leaflet.
Some patients refuse, or are unable to give, informed consent. If such patients appear to be in urgent need of ECT- for example, refusal to drink leading to dehydration- they may be treated as an emergency either under common law or under Section 62 of the Mental Health Act 1983.
However, it is much more usual to apply Section 3 of this Act, and to seek the necessary second opinion from a doctor appointed by the Mental Health Act Commission.
MYTHS Many patients are horrified when ECT is first suggested. The public perception, reinforced by certain sections of the media, is of ěunmodifiedî ECT as it used to be given thirty years ago without an anaesthetic.
There were frequent physical complications such as broken teeth and bones, plus the dehumanising character of the experience, for example patients were often treated one after another in a public ward, with no privacy and no tranquillising medication.
Modern administration of ECT is very different; patients are anaesthetised, treated and recovered in privacy, and complications are rare. Many patients who have been successfully treated with ECT ask for further treatment if their illness recurs. Research has shown that over half those patients who have had ECT consider it less unpleasant than going to the dentist.
NICE reviewed ECT in 2003 (
2), and ě ..recommended that electroconvulsive therapy (ECT) is used only to achieve rapid and short-term improvement of severe symptoms after an adequate trial of other treatment options has proven ineffective and/or when the condition is considered to be potentially, life-threatening, in individuals with:
ď severe depressive illness
ď catatonia
ď a prolonged or severe manic episode.î
This is uncontroversial and in line with modern practice. They more controversially opined that ěit is not recommended as a maintenance therapy in depressive illnessî, whereas there is a tiny number of patients (a handful per district) where maintenance ECT, other treatments having been tried and failed, seems to be the only way to keep them out of hospital.
The Royal College of Psychiatrists produces guidance on the commissioning and operation of a high quality ECT service (
3).
FOR THE FUTURE Developments may include the use of gentler forms of stimulus such as transcranial magnetic stimulation (
4).
PSYCHOSURGERY Psychosurgery is brain surgery carried out to relieve a patientís suffering by changing mood or behaviour. Latest figures indicate that only 7 operations were done for the 2- year period 2004-5 (
5). It has thus become a near obsolete-treatment, probably carried out for only the most intractable cases of OCD.
The history of psychosurgery serves to illustrate the way that the relative influences of the biological and the psychological approaches to psychiatry have varied over time. During the early decades of the twentieth century psychological theories predominated, in particular the various schools of psychoanalysis.
However, their results in the treatment of psychiatric patients proved disappointing, particularly in relation to the rapid progress being made in other branches of medicine. This led to a renewed search for what became known as physical treatments (including convulsive therapy, either electrically induced or by chemical means, psychosurgery, insulin coma, electrosleep).
Of these methods, only ECT has been shown effective in prospective randomised controlled trials, and the rest have now fallen out of use. Psychiatristsí enthusiasm for these and other unproven physical treatments, often used without informed consent, was a major reason for the emergence of the ěantipsychiatryî movement in the 1960s.
Moniz introduced psychosurgery in Portugal in 1935. During the next twenty years many patients in mental hospitals all over the world underwent lobotomy, entailing large-scale, blind destruction of brain tissue. Some responded well, but others gained no benefit, suffered marked unwanted effects or even died. The introduction in the 1950s of an effective antipsychotic drug (chlorpromazine) was followed by a secular decline in psychosurgery.
It is conceivable that it may return in the future in a modified form, with the more precise use for example of fine electrodes precisely implanted and available for so-called ědeep brain stimulationî (DBS).
FURTHER VIEWING A video demonstrating the practical administration of ECT is available from the Royal College of Psychiatrists, 17 Belgrave Square, London SW1X 8PG.
