OVERDOSE/TOXICOLOGY

Question 1

Describe the clinical features, investigation and treatment of alcohol intoxication.

Answer 1

Clinical features:

• Reduced consciousness
• Slurred speech
• Vomiting or feeling nauseated
• Hypoglycaemia
• Hypotension

Investigation:

Blood alcohol level

Treatment:

• Hypoglycaemia → glucose
• Prevent aspiration of vomit
• Haemodialysis if blood alcohol level > 500 mg/dl

Question 2

Describe the clinical features, investigation and treatment of paracetamol overdose including the importance of monitoring of hepatic and renal function.

Answer 2

Clinical features:

• RUQ pain at around 48-72 hours(?hepatic necrosis)
• Vomiting
• Deranged LFTs
• Liver failure
• Encephalopathy
• Coma
• Metabolic acidosis with raised lactate

Investigation:

• Plasma paracetamol level at least 4 hours after ingestion
• Hx to establish:
  
  • Single or staggered dose?
  • Time since last ingestion?
  • Total amount ingested (mg/kg)

Treatment:

Doses < 75 mg/kg in 1 hour are unlikely to cause harm, unless staggered.

Dose > 150 mg/kg in any 24 hour period are associated with serious adverse effects. Dose > 12g are potentially fatal.

• If presenting within 1 hour of ingestion consider activated charcoal
• 21 hour IV Acetylcysteine for those who:
  
  • Taken < 8 hours ago and meet treatment line
  • Dose > 150 mg/kg taken between 8-24 hours ago
  • Taken > 24 hours ago and have jaundice/hepatic pain
  • Taken 24 hours ago and have detectable levels, ALT raised or INR > 1.3
  • Staggered dose
  • Delayed presentation or paracetamol level not available for 8 hours from last ingestion

Question 3

Describe the clinical features and management principles of other overdoses that present commonly to the Emergency Department, including tricyclic antidepressants, benzodiazepines, opiates, cocaine and aspirin.

Answer 3

Question 4

List the antidotes available to treat specific poisons, e.g. for paracetamol, opiates,benzodiazepines, beta-blockers, tricyclic antidepressants

Answer 4

• N-acetylcysteine for paracetamol
• Naloxone for opiates
• Flumazenil for benzodiazepines
• Glucagons for beta-blockers
• Sodium bicarbonate for tricyclic antidepressants