ELECTROCONVULSIVE THERAPY

 Written by:

Chittaranjan Andrade, MD 
Additional Professor 
Department of Psychopharmacology 
National Institute of Mental Health and Neurosciences, Bangalore 560 029, India

 Member of the World Federation of Societies of Biological Psychiatry Task Force on ECT

Electroconvulsive therapy (ECT) is a form of treatment that is sometimes used in the management of severe depression or psychosis, including patients with bipolar disorder. Although the treatment is effective, and can even be life-saving, it has been reviled as a professional assault on the patient, and has been accused of producing brain damage.

The general public and the mass media view ECT with misgivings because electricity is passed through the brain, the seat of reason, and because the patient's 
body appears to convulse horrifically as a result of the shock. ECT, however, is not a cruel treatment. This article seeks to reappraise ECT and to present
its modern practice. 

A patient advised ECT undergoes a full physical examination as well as tests such as the ECG and X-Rays; fitness to receive ECT is thus confirmed. ECT is 
usually administered in the morning after an overnight fast. The patient lies down in the ECT room and an anaesthetic drug, such as methohexital, is injected 
intravenously. This drug induces sleep and curtails the anxiety that the ECT procedure may otherwise occasion. Next, a muscle relaxant, such as succinylcholine, 
is injected. This drug paralyzes the voluntary muscles of the body and minimizes the violence of the convulsion. Sometimes, other drugs are also given to increase
the safety of the procedure; the use of such drugs depends upon individual need. While these pre-ECT treatments are being given, the patient is hyperventilated
with pure oxygen.

During ECT, a special device is used to pass a small current (usually 0.5-0.8 A) through electrodes applied to the head. The current lasts for a duration that is 
seldom more than four seconds. The total electrical charge that the patient receives is 0.1-0.3 C, on average (one coulomb [C] is the charge delivered when 
one ampere [A] of current is passed for one second). Much of the electrical charge during ECT does not actually reach the brain but instead traverses scalp 
tissues. It is clear, therefore, that a very tiny electrical stimulus is applied. This should reassure those who believe that large bolts of electricity strike the brain 
during ECT! 

The current applied activates the brain and elicits a seizure. This is demonstrated using electroencephalography (EEG) as a brief barrage of brain electrical 
activity. The occurrence of a seizure is essential for ECT to be effective. The stimulated brain activity, and not the electrical stimulus, induces the muscular 
contractions (convulsion) that characterize the seizure. The convulsion is mild and merely lasts a few seconds because of the effect of the muscle relaxant. 

The muscle relaxant that minimizes the muscular contractions also paralyzes the respiratory muscles. The patient is therefore artificially ventilated with pure 
oxygen for the few minutes that it takes for spontaneous breathing to resume. The entire process is painless, and the patient usually feels comfortable on awaking
15-30 minutes later, when the anaesthesia wears off. 

Patients usually require about 4-10 ECTs administered twice or thrice a week. More frequent ECT can be harmful while less frequent ECT may be less effective. 

Major depression is the single most important indication for ECT. In depressed patients, ECT can be of especial help when the patient is severely depressed, 
suicidal, psychotic, or stuporous.ECT is also useful in schizophrenia and mania, particularly in patients who do not respond adequately to medication. In bipolar 
patients who experience frequent switches between mania and depression (rapid cyclers), maintenance ECT can reduce the cycle frequency and increase period
of normal mood. Maintenance ECT is considered in greater detail below.

ECT is not used in neurotic, psychosexual, psychosomatic, organic, and other psychiatric disorders. Recent research however suggests that ECT may be effective 
in a few other conditions, including Parkinson's disease, delirium, and uncontrolled status epilepticus.

Why has ECT survived the advent of drug therapy in psychiatry? Well, ECT produces recovery faster than drugs; it is more effective than drugs at times, and
is often effective in drug-resistant cases. Thus, ECT reduces suffering, hospital stay, and hospital costs; it returns the patient earlier to his social and 
occupational environment; and, it can also be life saving as in stuporous, suicidal or violent patients. 

The beneficial effects of ECT wear off over time; so, after the ECT course the patient is usually prescribed appropriate antidepressant or antipsychotic drugs 
to maintain the ECT-induced improvement across the succeeding months or years. Patients who relapse may require further courses of ECT. 

Patients who repeatedly relapse despite maintenance drug therapy may require maintenance ECT, administered once-weekly to once-monthly, in order to remain 
well. Maintenance ECT is administered in exactly the same way as regular ECT. The patient needs to visit the hospital only on the day of the treatment; he can 
return home, in the company of an attendant, after recovering from the treatment.
How does ECT act? This is an unfair question because, although we make educated guesses, we do not know for certain how antidepressant and antipsychotic 
drugs really act. In fact, we are far from an understanding of even the fundamental abnormality in the brain in mental illnesses. With these caveats, a tentative 
view is very simply expressed. 

Nerve cells in the brain communicate with each other through chemicals called neurotransmitters. ECT and the drugs used in psychiatry modify the actions of these
neurotransmitters and the receptors upon which they act. Secondary changes are produced within the nerve cell and its nucleus; these lead to changes in the way 
the nerve cell functions, as well as in the way it branches out and meets other nerve cells. Somewhere in this process, out of a host of neurotransmitter changes,
receptor changes, intracellular changes, and other changes, the abnormality that is responsible for the mental illness is either corrected or compensated for.

Despite the superficially alarming nature of ECT, the treatment is associated with a death rate of only about 1 in 25,000; this is lower than the death rates
with drug therapy. Adverse effects with ECT are usually few and mild, and      include transient confusion, aches, and pains immediately after the treatment.      
The most important adverse effect of ECT is forgetfulness. 

Forgetfulness with ECT is usually mild, fragmentary, short lasting, and confined to events during the ECT course. Occasional patients, however, experience more 
severe memory loss, such as the forgetting of events in their personal lives. The memory loss is due to chemical changes in the brain and not due to brain damage.
Extensive investigation using a plethora of biological techniques have all documented that ECT does NOT produce  brain damage.

In order to improve the effectiveness of ECT and reduce the adverse effects, a number of technical improvements have been made. With the administration of 
unilateral ECT, only half the brain is stimulated by the electric current; this reduces the memory problems induced by ECT, but may also reduce the benefit 
occasioned by the treatment.

Brief-pulse waveforms and constant current ECT devices now precisely measure and administer an appropriate dose of current during ECT. These devices render 
obsolete the conventional sine wave, constant voltage devices. Precise electrical dosing during ECT is important because larger electrical stimuli may induce greater
improvement, but may also induce greater cognitive impairment. Methods are being examined to evaluate the ECT seizure on-line using computerized EEG 
assessments.

Refinements in the theory and practice of ECT have made the treatment safer and more effective. It is likely that the treatment will survive indefinitely, unless a 
new form of treatment, transcranial magentic stimulation (TMS), becomes established. TMS is the induction of electric currents in the brain using magnetic 
stimulation techniques. Selective brain zones can be stimulated and psychiatric benefits can be obtained without the need for the induction of a seizure.
TMS is technologically in its infancy, however, and as yet ECT is not under threat.

 THE HISTORY OF ECT

Sixty years ago, virtually no meaningful treament was available for mentally disturbed patients. Then, ECT was introduced....

The story began with von Meduna, a Hungarian psychiatrist, who observed that epilepsy and schizophrenia rarely coexist, and that when they do coexist, the occurrence of seizures reduced the severity of psychosis. Meduna therefore treated schizophrenic patients by inducing seizures using drugs such as intramuscular camphor or intravenous pentylenetetrazol. Meduna's patients improved dramatically, and for the first time a meaningful treatment became available in psychiatry.

Seizures induced by the injection of drugs could not be controlled in number, duration, severity, and time of occurrence. Therefore, alternate means of inducing seizures were sought.

Cerletti and Bini, neuropsychiatrists in Rome, had observed that electricity was being used to stun pigs in slaughterhouses; these pigs frequently convulsed when the current was passed. Cerletti and Bini therefore thought of using electricity to similarly induce seizures in humans. After two years of experimentation in animal models, they optimized electrical details such as dose, duration, and site of electrode placement.

In April 1938, they were ready for the administration of the first ECT. The treatment was conducted under a veil of secrecy because they were uncertain of the outcome and were afraid of a public outcry. Fortunately for them and for psychiatry, the treatment was uneventful, and the patient showed improvement.

A series of studies quickly established the usefulness of the treatment, and the practice of ECT spread rapidly across the globe. Today, despite the availability of effective drugs for the treatment of mental illness, ECT retains an important place in psychiatry and is widely used all over the world.

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