Propranolol and sotalol = 'one pill can kill'

WELL HELLO THERE. (rubs hands evilly)

	Co-ingestions and action on Na channel comes with higher mortality
Etiology	- Vasodilatory/vasogenic shock mostly from b-blockers - Sodium channel antagonism from propranolol, labetalol, carvedilol
Clinical presentation	A/B: cardiogenic shock → pulmonary oedema C: hypotension, bradycardia D: Seizures, coma (from Na channel blocking effects) E: Hypoglycaemia, AKI
Pathogenesis	Hepatic/renal elimination mostly Hypoglycaemia - from ↓ pancreatic glucagon release and ↓ adrenaline counter-regulation
Diagnostic investigations	ECG: bradycardia, various AV blocks, QRS widening → VT, VF, asystole (see below)
Management	Wide QRS/high degree block may not respond to atropine! Low dose Adrenaline as rescue +/- other pressors HIET Sodium bicarb Glucagon - less in favour now (theoretically, should increase cAMP independent of adrenoceptors) Observation - t½ up to 10-12h for bisoprolol; or modified release preparations for propranolol Complications:

management

airway/breathing

hyperventilation → aiming pH 7.5

circulation

QRS prolongation - sodium bicarb
ventricular arrhythmias - bicarb
bradycardias - atropine, isoprenaline
sotalol can cause torsades des pointes → magnesium
severe hypotension, heart failure or cardiogenic shock - glucagon
- 5-10mg (adult), bolus then infusion if needed
- 50-150mcg/kg (paed)


Cardiac arrest, VT or QRS ≥ 160 msec	Administer a rapid bolus of 100 mmol (i.e.100 mL 8.4%) sodium bicarbonate urgently. A repeat bolus may be administered if there is persistent QRS prolongation or arrhythmias and the pH is <7.5.
QRS 120-160 msec	Administer 50 mmol (i.e. 50 mL 8.4%) sodium bicarbonate. A repeat bolus may be administered if there is persistent QRS prolongation
Children with QRS prolongation	Administer 1-2 mL/kg 8.4% (centrally) or 2-4 mL/kg 4.2% (peripherally): If cardiac arrest or VT – as a bolus If prolonged QRS alone – over 20 minutes

disability

seizures after propranolol overdose → high risk VT
→ give bicarb - 50ml of 8.4%
metab acidosis - consider high insulin euglycaemic therapy after disucsison with NPIS

#toxicology

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