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
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