Thymatron
®
System IV Instructions for Use
13
RISK OF THYMATRON® COMPONENT FAILURE
In the extremely rare event of catastrophic failure of an ECT device component, there is a remote possibility of
delivering an electrical stimulus dose in excess of that set by the operator, potentially causing excessive memory
disturbance. To prevent such an occurrence, the Somatics Thymatron® device includes an independent separate
redundant safety circuit that automatically measures the electrical charge of the output each time the stimulus
button is pressed and prevents delivery of any stimulus charge exceeding by more than 5% that set by the
operator. To test the integrity of the electrical connection to the patient, the Somatics Thymatron® device
includes a static impedance test initiated by a button press. The test current is too small to be felt. This test helps
assure good electrode contact and prevent excessive heat release onto the skin.
EFFICACY AND SAFETY OF THE THYMATRON® ECT DEVICE
The below review of the clinical research literature on electroconvulsive therapy (ECT) focuses on the risks and
benefits of the most widely-used Thymatron® ECT device models: the DG, DGx, and System IV
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This review
emphasizes controlled studies with random assignment, blind ratings and statistical validation; older
impressionistic reports without validated observations are not included.
Several old reports not involving a Thymatron® ECT device stated concern about potential adverse effects of
ECT on brain function, but the technique of ECT and electronic design of the devices used for this treatment
have since advanced to mitigate those concerns. An old study claiming brain injury in cats receiving electrically-
induced convulsions (Alpers and Hughes, 1942) failed to use muscle-relaxant drugs before stimulation or proper
comparison animals. Breggin (1979) emphasized cerebral petechial hemorrhages (small blood spots on the
brain), but when animals were restrained from banging their heads no petechiae occurred (Siekert et al, 1950).
A prospective study in patients receiving modern ECT that employed blindly-analyzed serial magnetic resonance
images obtained before, 2-3 days after ECT, and 6 months later revealed no evidence of brain injury from ECT
(Coffey et al, 1991).
EFFICACY OF THE THYMATRON® ECT DEVICE
Abbott et al (2013) reported twelve DSM-IV manic-depressive depressed patients treated with a Thymatron®
System IV, rated on the Hamilton scale before and after a course of ECT. They exhibited a statistically
significant mean depression scale improvement of 27.6 points. Nine patients achieved remission; three did not.
Azuma et al (2007) studied 14 treatment-resistant depressives who received bilateral ECT with a Thymatron®
System IV. Highly significant improvement in Hamilton Depression Scale scores was achieved, with 43%
scoring under 8 post-ECT. Postictal suppression measured by the Thymatron® System IV significantly predicted
therapeutic outcome.
Heikman et al (2002a) used a Thymatron® DGx ECT device to treat 24 major depressives randomly assigned to
high-dose right unilateral ECT, moderate-dose right unilateral ECT, or low-dose bifrontal ECT. Blindly-obtained
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The DG, DGx and Thymatron System IV deliver the same electricity. The Thymatron IV differs from previous models
in monitoring and in ways that the doctor can select the electrical stimulus. Somatics no longer sells the DG or DGx
