Electroconvulsive therapy, which works by creating a generalized seizu
re, is used most frequently to treat medication-resistant depression.
Other indications for electroconvulsive therapy include severe depress
ion with suicidal ideation, acute mania and severe psychiatric illness
with food and fluid refusal. Electroconvulsive therapy may be adminis
tered as an inpatient or outpatient procedure. Treatments are usually
administered three times a week for six to 12 treatments. Before this
therapy is used, a thorough medical and anesthetic history should be o
btained, and a complete physical examination, an electrocardiogram and
appropriate laboratory studies should be performed to rule out anemia
, electrolyte imbalances, and cardiopulmonary and neurologic risk fact
ors. Heart rate and rhythm, oxygenation, blood pressure and, often, th
e electroencephalogram are monitored continuously while the patient is
anesthetized with a short-acting hypnotic agent and a muscle depolari
zing agent. After electroconvulsive therapy, antidepressant or lithium
therapy significantly reduces the symptom relapse rate.