A to E: Disability - Acute poisoning

Question 1

What is the significance of acute poisoning?

Answer 1

For people aged <40:

• Leading cause of cardiac arrest
• Common cause of non-traumatic coma
• Major reason for hospital admission
  
  • Accidental (typically children <5yrs)
  • Illicit drugs (typically adolescents)
  • Deliberate self-harm (adults)

Question 2

Name four drugs commonly involved in overdose

Answer 2

• Paracetamol (50%)
• NSAIDS: ibuprofen; aspirin
• Benzodiazepines; zopiclone
• Drugs of misuse
  
  • Opioids
  • TCAs: amitriptyline
  • SSRIs

Question 3

Name four presenting features of acute poisoning (general)

Answer 3

• Able to provide Hx
  
  • Majority present immediately after accidental intake
  • Delay presentation: unaware; deliberate self-harm
• Direct observation: eating; materal around mouth; on clothes
• Consider acute poisoning in:
  
  • Delirium
  • Hypoglycaemia
  • Abnormal LFTs
  • Unexplained seizure
  • Several people presenting with similar symptoms
  • Recurrent/chronic unexplained symptoms in children

Question 4

Name three presenting features of paracetamol poisoning

Answer 4

• Often asymptomatic: low threshold for urgent admission
• NaV: usually settles within 24h
• Persistent NaV ± right subcostal pain: hepatic necrosis
  
  • Encephalopathy; hypoglycaemia; haemorrhage; cerebral oedema; death
• Coma; reduced GCS: suggest polysubstance use
  
  • Commonly alongside opioids or alcohol

Question 5

Name three presenting features of aspirin poisoning

Answer 5

• Hyperventilation
  
  • ​Mixed respiratory alkalosis and metabolic acidosis
• Tinnitus; deafness
• Vasodilation
• Sweating
• Coma (if very severe)

Question 6

Give four presenting features of TCA poisoning

Answer 6

• Dry mouth; mydriasis; urinary retention; tachycardia
• Seizures
• Coma
• Cardiac conduction defects (VT); arrhythmias
• Hypothermia
• Hypotension
• Hyperreflexia
• Respiratory failure

Question 7

Give four presenting features of SSRI poisoning

Answer 7

• NaV
• Agitation
• Tremor
• Nystagmus
• Drowsiness; convulsions
• Sinus tachycardia

Question 8

Give three presenting features of benzodiazepine poisoning

Answer 8

• Drowsiness
• Dysarthria
• Ataxia
• Nystagmus
• Respiratory depression; coma

Question 9

List three presenting features of cocaine poisoning

Answer 9

• Agitation
• HTN crisis; tachycardia
• Mydriasis
• Hallucinations
• Hyperthermia
• Hypertonia; hyperreflexia
• Chest pain; arrhythmias; MI with angina
  
  • ​Cocaine-induced artery spasm

Question 10

Give three presenting features of opioid poisoning

Answer 10

• Drowsiness; coma
• Respiratory depression
• Pinpoint pupils

Question 11

Give three presenting features of ecstasy poisoning

Answer 11

• Delirium
• Coma; convulsions
• Hyperthermia
• Rhabdomyolysis
• AKI; acute hepatitis
• DIC
• ARDS
• Hyperreflexia

Question 12

Request four investigations for acute poisoning

Answer 12

• Obs: HRl BP; RR; Temp
• ECG
• Weight
• If unconscious or severe toxicity:
  
  • U+Es
  • Paracetamol concentration
  • VBG/ABG

Question 13

Outline the general management of acute poisoning

Answer 13

• Most can be treated with suppotive care and monitoring
  
  • Serious clinical effects occur in <5%
• ABC assessment
• ALS algorithm for cardiac arrest; hypoglycaemia; seizures
  
  • Benzodiazepines for sustained seizures or agitation
• Consult TOXBASE for advice and specific antidotes

Question 14

What is the specific antidote for opioid poisoning?

Answer 14

Naloxone

400 mcg IV (also available via IM/SC/IN)

Consider repeat doses

Question 15

What is the specific antidote for benzodiazepine poisoning?

Answer 15

Flumazenil

As long as no history or risk of seizures

Question 16

What is the specific antidote for TCA poisoning?

Answer 16

Sodium bicarbonate

Question 17

What is the specific antidote for cocaine poisoning?

Answer 17

Small dose of IV benzodiazepines

Question 18

What is the antidote for salicylate poisoning?

Answer 18

Urinary alkalinisation + IV sodium bicarbonate