TOXICOLOGY

Response>5 mg/kg = toxic
>10 mg/kg - severe - effects occur within 2-4 hours
>30 mg/kg - severe

Requires close observation for >6 hours if does not develop toxicity in area with cardiac monitoring

ResponseSinus tachycardia - Anticholinergic activity and inhibition of noradrenaline uptake
Hypotension - Reduced myocardial contractility and peripheral alpha blockade

ResponseECG - Cardiotoxicity tachycardia, long QT, long PR, QRS widening (>100 risk of seizure, >160 risk of VT)
Paracetamol level - screening test in overdose
b-HCG - young woman, may complicate management
VBG - Monitor acidosis/response to treatment

ResponseSeizure Terminate seizure

• sodium bicarbonate - 1-2mmol/kg IV.
• Midazolam 5mg if seizure ongoing. Endpoint = termination of seizure

Serum alkalanisation

• Repeat ECG - looking for signs of toxicity. If QRS prolongation/hypotension
• 100 mmol 8.4% sodium bicarbonate with endpoint of QRS narrowing and haemodynamic stability

Early intubation to control airway and ventilation with predicted clinical course of coma and respiratory acidosis contributing to worsening sodium channel blockade.

• Appropriate use of RSI drugs (Ketamine 100, Roc 100 mg)

End point: Hyperventilate TV 6-8 mL/kg, PEEP 5, FiO2 to maintain sats >95%. RR targeted to caheive pH 7.5-7.55.
Fluids 20 mL/kg n/s or Hartmann’s +/- vasopressor if ongoign hypotension - SBP >90, MAP>65
Activated charcoal 50g once airway secured given significant ingestion
Supportive - K+ replacement with alkalinsation
Consider 3% N/S if refractory hypotension aiming Na 150)

ResponseI’ve basically changed this chapter so its just info on each drug in a table form in a few pages. It was easier for me.