Electroconvulsive therapy, or ECT, is the fastest and surest way to relieve depression. When other treatments have failed, when a patient is too suicidal for anything less effective, when depression is too severe to wait for drugs to work, electroconvulsive theapy is the treatment of choice. Compared to drugs, though, it is expensive, often requires hospitalization, and demands a greater commitment from patients. For these reasons it is reserved for more serious and unresponsive depressions.
A treatment consists of a medically controlled seizure initiated by passing an electric current between two scalp electrodes. If the seizure were unmodified it would look like a typical epileptic convulsion lasting 20 seconds to a minute and causing the muscles of the body to contract rhythmically.
The term "medically controlled seizure" refers to a number of treatment modifications. Before the treatment, patients receive a short-acting anesthetic in a vein so they are anesthetized throughout the procedure. Once anesthetized, they receive a drug to relax the muscles to prevent the hard muscle contractions that are associated with epileptic seizures. Since the seizure and the muscle relaxant can both interfere with breathing, an anesthesiologist provides oxygen through a face mask. Next, the treating physician passes an electric current of several seconds duration to start the seizure. After the seizure ends and the anesthetic has worn off, the next step is a short stay in the recovery room. ECT causes mental confusion that is most marked during the hour after treatment and close observation needs to be provided during this time. Once the confusion has cleared substantially patients are discharged from the treatment suite.
ECT is given as a series of 8 to 12 individual treatments three days a week, so a series of treatments requires three to four weeks to complete. Improvement often begins after a week but the treatment is continued until the depression has cleared. An antidepressant medication is started toward the end of the treatment series to provide further protection against a recurrence of the illness.
Risks and Side Effects
ECT is a safe medical procedure. It has been given safely in all nine months of pregnancy, in advanced age, and in a wide variety of medical conditions. The benefits must be weighed against the risks of worsening the medical illness, though, particularly in the face of a recent heart attack, heart failure, unstable angina, respiratory failure, recent blood clots, or any condition causing pressure on the brain.
The side effects of ECT are usually not serious though they can be bothersome. Headache and nausea on awakening from the treatment are a common complaint. This can be treated with medicine for pain and nausea and prevented by giving these drugs before the anesthesia wears off.
The most publicized effect of ECT is its effect on memory. In order to remember an experience the brain must record the event and then store it in long-term memory for recall hours, days or even years later. ECT interferes with this storage. Thus, events that occur during the course of treatment may be forgotten, but events that have already been stored remain intact. After the treatments are over the ability to store new memories returns to normal. (One exception to this rule is that some memory loss occurs in a retrograde fashion; memories formed shortly before starting treatments are affected the most, though treatments can affect memories for as far back as a year.) The net effect is that memory for many events during and shortly before the treatment course can be lost permanently, but the ability to retain and recollect new memories returns to normal after the treatments are over.
A question often asked about ECT is whether it causes permanent brain damage. Because an electric current is passed through the brain and memory is altered, many people have been concerned that the treatment may injure the brain. Medical research has addressed this question by carefully testing a wide variety of mental abilities in persons who have had ECT and the results are reassuring. No evidence of permanent brain damage has ever been uncovered.
Memory loss can be minimized by stimulating only one side of the head. The left side of the brain is usually dominant, so stimulating on the right side typically causes less memory loss than stimulating both sides. This benefit has to be balanced against the observation that stimulating on one side is sometimes less effective so that more treatments are needed to recover. However, in recent years the effectiveness of unilateral treatments has improved considerably.
How effective is ECT for depression? Most studies find that approximately 80% of patients recover or are much improved. The rate of recovery can be as important as effectiveness. Recovery usually begins after a week whereas drugs require at least two weeks and sometimes take as long as six. ECT also remains quite effective in patients who have not responded to one or more trials of antidepressant drug therapy.
ECT is an effective treatment for mania, although it is rarely used for this now because the illness responds so well to drugs. ECT is reserved for the unusual circumstance when manic excitement and psychosis cannot be controlled with antipsychotic and mood stabilizing medications.
In the past ECT was used extensively to treat schizophrenia but this is rarely necessary now because most schizophrenic episodes can be controlled with antipsychotic medication. With an expanding armamentarium of new antipsychotic drugs to treat schizophrenia, ECT will probably be needed less and less. When it is needed, it is effective against psychotic symptoms, such as delusions and hallucinations, and complicating depression. It is not an effective treatment for the emotional and social withdrawal of schizophrenia unless these behaviors are caused by psychotic symptoms.
ECT is very effective in catatonia. This severe abnormality of movement usually presents with profound withdrawal and absence of spontaneous movements or responses to other people. Bizarre movements such as unusual postures can be seen as well. It usually appears as a complication of schizophrenia or manic-depressive illness, but it also can complicate underlying medical illness. Catatonia is so responsive to ECT that patients often improve noticeably after a single treatment. Although it is rare it is an important use of ECT because it responds poorly to medications.
Recent changes in our health care system have changed the way ECT is given as well. Until recently, ECT has been a treatment for hospitalized patients, but today many patients are receiving part or all of their treatments as outpatients. A common practice is to begin the treatments in the hospital and complete them at home once the depression has lifted enough to return home safely. Another group of patients who benefit from outpatient ECT are those who have not responded to other treatments and need maintenance ECT to remain well. Not everyone can be treated as an outpatient, however, because it requires someone to transport the patient to and from treatments and remain with them on the day of the treatment. Even with these restrictions, some people suffering from depression now receive all of their treatments without entering a hospital.