another ECG case…
The Case.
I was superficially involved in this case of a 32 year old suicidal patient who ingested two full packets of Solian (amisulpride) (~ 24 grams) approximately 90 minutes prior to arrival to ED.
On initial assessment he was GCS 12/15 & had a systolic BP of 115 mmHg.
This is his ECG….
[DDET Amisulpride Toxicity…]
AMISULPRIDE TOXICITY.
Amisulpride – What is it ?
a benzamide neuroleptic (atypical antipsychotic) with high affinity for the dopamine (specifically D2-2) receptor.
- used for acute & chronic schizophrenia (both negative & positive symptoms)
- unlike other neuroleptics, it has minimal affinity for 5HT, alpha, H1 or cholinergic receptors.
Dose-based Risk Assessment.
- < 8g = mild-moderate sedation, mild anticholinergic features.
- QT prolongation & torsades are reported (in as little as 4.6g ingestion)
- 8-15g = Increasing sedation & depressed level of consciousness.
- Cardiotoxicity includes hypotension, QRS & QT prolongation, bundle-branch blocks & torsades.
- > 15g = Significant risk of delayed coma & cardiotoxicity…
Signs & Symptoms.
- Mild-Moderate: Mydriasis, lethargy, drowsiness and sedation, bradycardia, agitation, hyperthermia and extrapyramidal symptoms.
- Severe toxicity: Seizures, coma, hypotension, and QTc prolongation. Torsades & VT are reported in intentional overdose.
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[DDET Management…]
Management.
- Resuscitation area / full cardiorespiratory monitoring.
- Patients may require intubation / mechanical ventilation
- Minimum of 16 hours telemetry mandated for ingestion >4g
- Decontamination (oral activated charcoal) is recommended for > 4 grams in previous 4 hours.
- No antidote.
- Enhanced elimination not useful
- Control of QT / risk of Torsades
- Magnesium (2g IV over 1-2 minutes, repeat x1 –> infusion of 0.5-1.0g / hour)
- Chemical or electrical atrial overdrive pacing.
- Correct electrolyte abnormalities (specifically hypomagnesaemia, hypokalaemia & hypocalcaemia)
Disposition.
As a rule; all ingestions > 4 grams should be monitored for at least 16 hours and until all ECG intervals are normal….
- Asymptomatic adults with inadvertent/minor exposure may be monitored at home.
- Significant/deliberate amisulpride overdose are observed for at least 16 hours after ingestion.
- Continuous cardiac monitoring and serial ECGs.
- If no dysrhythmias or QT prolongation at 16hrs –> discharged after psychiatric evaluation.
- Dysrhythmias or QT prolongation on ECG –> intensive care setting for continuous cardiac monitoring and treatment.
[/DDET]
[DDET As for our patient…]
ECG: Sinus rhythm @ 83bpm. Normal axis. PR ~200ms. QRS ~120ms. QTc ~560ms !!!
His management (after discussion with our Toxicology gurus) included;
- Intubation
- NG tube w/ activated charcoal administration
- Two further doses of charcoal
- MgS04 (20mmol x2)
- Isoprenaline infusion with target HR >100 bpm
- Dropped QT down to ~500msec
He survived his first night in the ICU….
[/DDET]
[DDET References]
- Murray L, Daly F, Little M & Cadogan M. Toxicology Handbook. 2nd Edition. Elsevier 2011.
- Isbister GK et al. Amisulpride deliberate self-poisoning causing severe cardiac toxicity including QT prolongation and torsades de pointes. Med J Aust 2006; 184 (7): 354-356.
- Isbister GK, Balit CR, Macleod D, Duffull SB. Amisulpride overdose is frequently associated with QT prolongation and torsades de pointes. J Clin Psychopharmacol. 2010 Aug;30(4):391-5.
- http://lifeinthefastlane.com/book/toxicology/amisulpride/
- Micromedex 2.0 (Toxicology Summary) “SULPIRIDE AND RELATED AGENTS”
- http://lifeinthefastlane.com/ecg-library/basics/qt_interval/
[/DDET]
