Electro Convulsive Therapy

ECTDr.D.Raj Kiran.

What is ECT

• ECT- Application of electric current to the head with the aim of inducing a controlled tonic-clonic seizure, usually at regular intervals, to achieve an improvement in an abnormal mental state.

• Modified ECT- Induction of cerebral seizure under anaesthesia.

• Unmodified ECT- Induction of cerebral seizure without anaesthesia.

History

• In 16th century, the Swiss alchemist Paracelsus gave camphor by mouth to induce convulsions and “cure lunacy.”

• In 18th & 19th century, several cases of convulsions induced by chemical means were documented.

History

• Manfred Sakel was the developer of insulin shock therapy.

• He noted that insulin-induced coma and convulsions had a change in the mental state of drug addicts and psychotics.

• Complications were high.

History

• In 1934, Lazlo Meduna, a Hungarian psychiatrist, injected camphor in oil into a catatonic schizophrenia, causing grand mal seizure.

• After series of such treatments pts recovered.

• Later Camphor was replaced by pentylenetetrazol.

History

• Pentylenetetrazol caused lot of unpleasant sensations.

• The concept of applying electricity was developed.

• Swiss scientists induced seizures in dogs using direct electrical current.

Birth of ECT

• Italian scientists, Cerletti and Bini subsequently succeeded in applying electricity directly to the human scalp.

• In 1938, they treated an unidentified 39-year-old man who was found delusional in a train station.

• He recovered fully after 11 treatments without adverse Effects.

Birth of ECT

Ugo Cerletti Cerletti’s ECT machine

Effects of ECT

• During ECT, brain imaging shows- Hypermetabolic state– increases in cerebral blood flow (CBF).– increase cerebral metabolic rate (CMR).

• Post-ictal state- functional suppression– decreases in CBF.– decrease in CMR.

• Also during & after ECT, there are δ waves indicating reduction in neural activity.

Mechanism of action

• No “definitive theory” regarding the mechanisms of action.

• Psychological theories- patient expectation, placebo effects, forced regression, and contribution of retrograde amnesia to clinical response.

• These were proved to be incorrect.

Mechanism of action

• Biological theories- they are related to ECT's anticonvulsant effects.

• These effects manifest during a course of ECT.

• They include – progressive increases in seizure threshold. – progressive decrease in seizure duration. – increases in inhibitory neurotransmitters. – decreases in excitatory neurotransmitters.

Mechanism of action

• Recent studies-– Transient induction of increased pro-

inflammatory cytokines, – Increased expression of brain-derived

neurotrophic factor (BDNF),– Gene polymorphism,– Enhanced activity in the GABAergic,

glutaminergic and dopaminergic systems,– Enhance neurogenesis, synaptogenesis and

remodelling of synapses in hippocampus.

Electrical principles

• Waveforms– Sine wave- more cognitive deficits– Brief square wave- better efficacy & less

adverse effects.

• An adequate seizure is defined as– Motor seizure > 25 sec.– EEG seizure of 30-120 sec.– Rise of HR by > 50% during seizure.– Post-ictal rise in PRL.

Electrode placement

Bilateral• Electrodes are placed

apart over each hemisphere.

• More rapid therapeutic response.

• Mc- Bitemporal, Bifrontal.

Unilateral• Both electrodes placed

apart over non dominant hemisphere.

• Less marked cognitive deficits.

• Mc- Right unilateral.

Electrode placement

• Bilateral- electrode is placed 2.5 -4cm above the midpoint of line joining tragus & lateral canthus.

• Unilateral- another electrode at vertex.

Indications

• Major depression.• Mania.• Schizophrenia.• Catatonia.• Parkinson’s disease.• Intractable seizures.• Delirium.• Gilles de la tourette syndrome.• Hallucinogen induced psychosis.• Neuroleptic malignant syndrome (NMS).

Contra-indications

• Absolute- “none”• Relative-

– Space occupying intracranial lesion.– Raised ICP.– Recent MI with unstable cardiac function.– Vascular aneurysm.– Recent Intra cranial hemorrhage.– Retinal detachment.– Pheochromocytoma.– Anesthesia risk.

• Pregnancy is not a contraindication.

Pretreatment

• Informed consent• Evaluation-

– History & Examination.– Medical evaluation- systemic examination,

fundus, ECG, electrolytes.– Anaesthetic evaluation.

• Bite block• Anaesthetic agents- thiopental/propofol,

muscle relaxant (SCh), anticholinergics.

Adverse effects

• Nausea, vomiting, headache.• CNS-

– Post-ictal confusion.– Memory problems- retrograde > anterograde.

• Fractures & Muscle injuries- direct ECT.• Death- 1 in 25,000. causes could be MI,

Ventricular arrhythmias, respiratory complications.

Video….

• Video on Modified ECT