Anaesthesia for ECT Dr Hannah Rose April 2006

Overview Introduction to ECT Anaesthesia for ECT History Indications Practicalities Side Effects Anaesthesia for ECT Patient factors – Hx / Exam / Ix Venue / Equipment Conduct Induction / Muscle relaxation Recovery

History 1934 Von Meduna – Insulin induced seizures for schizophrenia 1938 Ugo Cerletti – Electric shock induced seizures Found to be more effective for mood disorders. Popular in 1940’s and 50’s 1962 ‘One flew over the Cuckoo’s Nest’ Waning popularity 60’s and 70’s Safer (Mortality 2-5 : 100 000)

Indications Life threatening illness Treatment resistance Attempted suicide / strong ideation Catatonia Refusal of food / fluids Depressive delusions / hallucinations Prolonged / severe manic episode Treatment resistance Depression Mania Schizophrenia (4th line treatment) Patient choice Maintenance therapy

Practical Aspects In- or out-patients First / repeat visit Consent ECT suite Anaesthetic Equipment ECT machine EEG monitor Electrode placement Dosing / duration Anaesthetic ‘Shared’ Airway Recovery / Home ECT machine – measured dose of electirical charge. Constant current stimulus by a Train if brief pulses 1 ms in length. Electrical dose range measured in Coulombs 25-1000mC. Electrode placement – bitemporal or unilateral --- lower incidence of memory and cognition loss and reduced time for reorientation

SIDE EFFECTS Safe low-risk procedure Risks associated with anaesthesia Cognitive dysfunction Prolonged seizures (>3mins) Injuries Cardiac risks Other – disorientation, h/a, PONV, weakness, anorexia, muscle aches, confusion Prolonged seizures more likely on 1st treatment and without eeg monitoring Worsens cognitive impairment and disorientation.

Anaesthetic Considerations HISTORY Routine Hx Previous Anaes Hx IHD / MI / HT / Valvular pathology / Dysrhythmias CVA / Raised ICP HH / GORD / NBM Diabetes Medications Drugs / Alcohol Reliability Consent Theophylline, TCA’s. SSRI’s, Lithium, neuroleptics lower seizure threshold Anticonvulsants, hypnotics, membrane stabilisers, MAOI’s raise the seizure threshold

Examination and Investigations Behaviour Airway (incl wobbly teeth) Vitals Routine Examination Ix only as needed

Contraindications Uncontrolled CCF DVT (untreated) Acute respiratory tract infection Recent MI / CVA Unstable major fracture Untreated phaeochromocytoma Raised ICP / untreated cerebral aneurysm “A balance must be struck between risks of anaesthesia vs untreated depression. ECT may be life-saving, under which circumstances there may be no absolute contraindications” Kelly and Zisselman (2000) Update on ECT in Older Adults. Journalof the American Geriatrics Society , 48, 560-566.

Venue and Equipment ECT Suite – Remote site ! Resuscitation equipment Experienced Anaesthetist and ODP Minimum mandatory monitoring +/- PNS Tilting trolley / padded cot sides Flow controlled oxygen supply + suction Anaesthetic / Emergency drugs Airway / Circuits / Disposables Clock Mouth guards EEG machine / ECT machine Staffed recovery area Written records

Conduct IV access Monitoring Pre O2 IV induction Muscle relaxant Mouth block Seizure induction Recovery

Seizure Induction Hyperventilation Minor tonic, then clonic activity Seizure pattern on EEG Missed seizures Prolonged / Tardive seizures Haemodynamic responses MISSED insufficient stimulus, too much impedance, hypercarbia, dehydration, drugs. Wait 20s and try again. Try reducing iv anaestheitci dose/change agent/BZD reversal PROLONGED / TARDIVE late return of seizure activity ----o2 and BZD/Anaesthetic agent to stop it.

Induction agent Methohexitone Barbiturate No longer available Lowered seizure threshold Propofol Phenol Widely used Increases seizure threshold, reduces duration Better cardiovascular stability Etomidate Imidazole Greater haemodynamic responses Longer seizures Useful in resistant cases or abortive seizures PONV / HP axis suppression

Muscle Relaxation Suxamethonium Dose (0.5-1mg/kg) Uses (Reduce muscle activity and injury) Stimulus post-fasciulations Non-depolarising if C / I

RECOVERY Adequate no. of trained personel Fully equipped O2 until awake and maintaining Sats Familiar escort Written instructions

Questions ?