|Drug Toxicity - clinical assessment
|Aspirin or Salicylates toxicity
|Ethylene glycol toxicity
|Carbon Tetrachloride Toxicity
|Renal Tubular Acidosis
|Tricyclic Antidepressant Toxicity
|Carbon monoxide Toxicity
|Paracetamol (Acetaminophen) toxicity
|Beta Blocker toxicity
|Calcium channel blockers toxicity
|Organophosphate (OP) Toxicity
|Toxin elimination by dialysis
|Drug Toxicity with Specific Antidotes
In lethal overdoses death is usually prehospital. Survival to hospital bodes well. Cyanide is a colourless liquid or gas that has a typical smell of almonds
- Potentially fatal usually pre-hospital
- Consider especially in domestic fires
- Used as an agent of genocide in gas chambers in WW2
- Hydrogen cyanide isolated from Prussian blue dye in 1786
- Cyanide first extracted from almonds around 1800.
- Exist as a gas, hydrogen cyanide, a salt, potassium cyanide.
- Accidental Cyanide Exposure may be seen in the chemical industry
- Deliberate suicide or homicide attempt.
- Enclosed fires involving plastics/foam or Smoke inhalation.
- Seen with prolonged or high dose therapeutic use of Sodium nitroprusside
- Causes death by inhibiting cellular respiration.
- Inhalation of hydrogen cyanide gas inhibits cytochrome a3
- Leads to blocking mitochondrial oxidative phosphorylation and a fall in ATP
- Dizzy, anxiety, ↑ HR, nausea, drowsy Eye irritation, skin flushing
- Soot in mouth, Cherry-red skin colour as oxygen is not extracted
- Smell of bitter almonds on the breath
- There may be chest pain and dyspnoea, seizures, coma.
- Moderate: Vomiting, low GCS, convulsions, cyanosis.
- Severe: Deep coma, fixed pupils, heart failure, arrhythmias, pulmonary oedema.
- ABG: Metabolic lactate acidosis, Anaerobic respiration
- Lactate : ↑↑ lactate suggests significant overdose.
- Give high 100% FiO2 oxygen, decontamination, and start IV fluids. Support may be enough. There are several treatment options
- Dicobalt edetate 300 mg IV over 1 minute followed by 50 ml of 50% dextrose but only if severe toxicity confirmed as it is itself very toxic.
- Hydroxycobalamim (Cyanokit) 5 g over 15 minutes combines to form cyanocobalamin
- Sodium thiosulphate (25 ml of 50% solution) enhances the conversion of cyanide to thiocyanate, which is renally excreted.
- Potentially fatal - take expert advice.