By Mayo Clinic Staff
Electroconvulsive therapy (ECT) is a procedure, done under general anesthesia, in which small electric currents are passed through the brain, intentionally triggering a brief seizure. ECT seems to cause changes in brain chemistry that can quickly reverse symptoms of certain mental illnesses.
ECT often works when other treatments are unsuccessful and when the full course of treatment is completed, but it may not work for everyone.
Much of the stigma attached to ECT is based on early treatments in which high doses of electricity were administered without anesthesia, leading to memory loss, fractured bones and other serious side effects.
ECT is much safer today. Although ECT still causes some side effects, it now uses electric currents given in a controlled setting to achieve the most benefit with the fewest possible risks.
Electroconvulsive therapy (ECT) can provide rapid, significant improvements in severe symptoms of several mental health conditions. ECT is used to treat:
- Severe depression, particularly when accompanied by detachment from reality (psychosis), a desire to commit suicide or refusal to eat.
- Treatment-resistant depression, a severe depression that doesn't improve with medications or other treatments.
- Severe mania, a state of intense euphoria, agitation or hyperactivity that occurs as part of bipolar disorder. Other signs of mania include impaired decision-making, impulsive or risky behavior, substance abuse, and psychosis.
- Catatonia, characterized by lack of movement, fast or strange movements, lack of speech, and other symptoms. It's associated with schizophrenia and certain other psychiatric disorders. In some cases, catatonia is caused by a medical illness.
- Agitation and aggression in people with dementia, which can be difficult to treat and negatively affect quality of life.
ECT may be a good treatment option when medications aren't tolerated or other forms of therapy haven't worked. In some cases ECT is used:
- During pregnancy, when medications can't be taken because they might harm the developing fetus
- In older adults who can't tolerate drug side effects
- In people who prefer ECT treatments over taking medications
- When ECT has been successful in the past
Although ECT is generally safe, risks and side effects may include:
- Confusion. Immediately after treatment, you may experience confusion, which can last from a few minutes to several hours. You may not know where you are or why you're there. Rarely, confusion may last several days or longer. Confusion is generally more noticeable in older adults.
- Memory loss. Some people have trouble remembering events that occurred right before treatment or in the weeks or months before treatment or, rarely, from previous years. This condition is called retrograde amnesia. You may also have trouble recalling events that occurred during the weeks of your treatment. For most people, these memory problems usually improve within a couple of months after treatment ends.
- Physical side effects. On the days of an ECT treatment, some people experience nausea, headache, jaw pain or muscle ache. These generally can be treated with medications.
- Medical complications. As with any type of medical procedure, especially one that involves anesthesia, there are risks of medical complications. During ECT, heart rate and blood pressure increase, and in rare cases, that can lead to serious heart problems. If you have heart problems, ECT may be more risky.
Before having your first ECT treatment, you'll need a full evaluation, which usually includes:
- A medical history
- A complete physical exam
- A psychiatric assessment
- Basic blood tests
- An electrocardiogram (ECG) to check your heart health
- Anesthesiologist review to go over the risks of anesthesia
These exams help make sure that ECT is safe for you.
The ECT procedure takes about five to 10 minutes, with added time for preparation and recovery. ECT can be done while you're hospitalized or as an outpatient procedure.
Before the procedure
To get ready for the ECT procedure:
- You'll have general anesthesia. So you can expect dietary restrictions before the procedure. Typically, this means no food or water after midnight and only a sip of water to take any morning medications. Your health care team will give you specific instructions before your procedure.
- You may have a brief physical exam. This is basically to check your heart and lungs.
- You'll have an intravenous (IV) line inserted. Your nurse or other team member inserts an IV tube into your arm or hand through which medications or fluids can be given.
- Your nurse places electrode pads on your head. Each pad is about the size of a silver dollar. ECT can be unilateral, in which electric currents focus on only one side of the brain, or bilateral, in which both sides of the brain receive focused electric currents.
Anesthesia and medications
At the start of the procedure, you'll receive these medications through your IV:
- An anesthetic to make you unconscious and unaware of the procedure
- A muscle relaxant to help minimize the seizure and prevent injury
You may receive other medications, depending on any health conditions you have or your previous reactions to ECT.
During the procedure:
- A blood pressure cuff placed around your ankle stops the muscle relaxant medication from entering the foot and affecting the muscles there. When the procedure begins, your doctor can monitor seizure activity by watching for movement in that foot.
- Monitors check your brain, heart, blood pressure and oxygen use.
- You may be given oxygen through an oxygen mask.
- You may also be given a mouth guard to help protect your teeth and tongue from injury.
Inducing a seizure
When you're asleep from the anesthetic and your muscles are relaxed, the doctor presses a button on the ECT machine. This causes a small amount of electric current to pass through the electrodes to your brain, producing a seizure that usually lasts less than 60 seconds.
- Because of the anesthetic and muscle relaxant, you remain relaxed and unaware of the seizure. The only outward indication that you're having a seizure may be a rhythmic movement of your foot if there's a blood pressure cuff around your ankle.
- Internally, activity in your brain increases dramatically. A test called an electroencephalogram (EEG) records the electrical activity in your brain. Sudden, increased activity on the EEG signals the beginning of a seizure, followed by a leveling off that shows the seizure is over.
A few minutes later, the effects of the short-acting anesthetic and muscle relaxant begin to wear off. You're taken to a recovery area, where you're monitored for problems. When you wake up, you may experience a period of confusion lasting from a few minutes to a few hours or more.
Series of treatments
In the United States, ECT treatments are generally given two to three times weekly for three to four weeks — for a total of six to 12 treatments. Some doctors are using a newer technique called right unilateral ultrabrief pulse electroconvulsive therapy that is done daily on weekdays.
The number and type of treatments you'll need depends on the severity of your symptoms and how rapidly they improve.
Some people may be advised not to return to work or drive until one to two weeks after the last ECT in a series or for at least 24 hours after the last treatment.
Many people begin to notice an improvement in their symptoms after about six treatments with electroconvulsive therapy. Full improvement may take longer, though ECT may not work for everyone. Response to antidepressant medications, in comparison, can take several weeks or more.
No one knows for certain how ECT helps treat severe depression and other mental illnesses. What is known, though, is that many chemical aspects of brain function are changed during and after seizure activity. These chemical changes may build upon one another, somehow reducing symptoms of severe depression or other mental illnesses. That's why ECT is most effective in people who receive a full course of multiple treatments.
Even after your symptoms improve, you'll still need ongoing depression treatment to prevent a recurrence. Ongoing treatment may be ECT with less frequency, but more often, it includes antidepressants or other medications, or psychological counseling (psychotherapy).
May 09, 2017
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