Thymatron
®
System IV Instructions for Use
43
within about 5% of the established target, keeping in mind the often dramatic rise in seizure threshold across a
course of treatment. Lower target values suggest that the treatment was less than fully effective; this might be
acceptable for selected patients but is clearly a matter of medical judgment.
Of course, as everywhere in medicine, clinical response is overriding. Patients whose EEG or peak heart rate
reflect a high seizure quality at lower dosage levels, but who are not showing clinical improvement, might
benefit from higher doses. Those who are enjoying a satisfactory clinical response despite apparently poor
quality seizures may require no dose adjustment.
TYPICAL COURSE OF TREATMENT
A typical acute course of treatment is two or three ECT sessions per week for between 6 and 10 total sessions.
Some patients may need more treatments to achieve maximum improvement. Patients with catatonia of
malignant severity may benefit from more frequent ECT sessions at the beginning of their course.
TARDIVE SEIZURE
A tardive seizure is a seizure that occurs after the ECT session. It is sometimes called a delayed onset seizure. It
is rare but dangerous, and fatality can occur. When it begins after an ECT session earlier that day clonus or
worsening delirium may be seen. Anticonvulsant treatment is typically immediate and vigorous, such as full
anesthesia with propofol. These patients should be considered for transfer to the ICU because of high risk for
sudden cardiopulmonary arrest, a risk that lasts several days.
A different presentation of tardive seizure is onset of seizure at an ECT session in response to anesthesia alone,
without an electrical stimulus. This can be managed in the same way an ECT seizure is, with insertion of a
mouth protector, vigorous ventilation and seizure monitoring. If the seizure lasts longer than about 100 sec
consider termination with propofol.
WORSENING OF PSYCHIATRIC SYMPTOMS
As with any treatment, some patients may show worsening along the course of ECT, and discontinuation of the
treatment becomes a consideration. Patients showing worsening should be suspected of having delirium from the
treatment or from combination with a complicating medical condition such as Parkinson's disease or a
medication such as a sympathomimetic agent, aminophylline or L-DOPA. New onset of a medical condition
should be considered, e.g., pneumonia, pulmonary embolus, MI, nonconvulsive status epilepticus, urinary tract
infection. Patients with motor retardation or poverty of thought before ECT may show apparent worsening when
ECT decreases these initial symptoms, with agitation, self-harm or suicidal behavior that should mitigate with
further ECT; suicide risk can increase during this time. Unrecognized alcohol or substance use disorder with
withdrawal symptoms can also cause worsening during a course of treatment.
