A to E: Disability - Paracetamol poisoning

Question 1

List three presenting features of paracetamol poisoning

Answer 1

• 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 2

What is considered significant ingestion of paracetamol?

Answer 2

Total dose / Patient weight (up to 110kg)

Significant if either:

• >75 mg/kg/d
• Reported dose unreliable

Question 3

Explain what is meant by ‘single ingestion’ and ‘staggered’

Answer 3

• ‘Single ingestion’: all taken in one go or <1h
• ‘Staggered’: ingestion over a period >1h

Question 4

Outline the management of paracetamol poisoning >24h ago

Answer 4

Ingestion >24h but within 1/52:

• Obtain INR; VBG; U+E; LFT; paracetamol level; FBC
• If jaundice or liver tenderness:
  
  • NAC immediately
  • Admit to AMU

Question 5

How is a staggered ingestion of paracetamol poisoning managed?

Answer 5

NAC within 1h of arrival

Question 6

When may activated charcoal be used for paracetamol poisoning

Answer 6

Ingestion <1h ago and >150 mg/kg

Question 7

What is the management of paracetamol poisoning <4h ingestion?

Answer 7

Admit to EDU on ‘Toxicology’ pathway

Unless co-ingestions make patient unsuitable for EDU admission

Question 8

Outline the managment of paracetamol poisoning >150mg/kg ingestion between 4-24h ago

Answer 8

>150mg/kg ingestion:

• Act <8h:
  
  • INR; VBG; U+E; LFT; paracetamol level (4hr); FBC
  • Determine if NAC needed
• Cannot act <8h:
  
  • NAC within 1h of arrival

Question 9

When is NAC indicated for paracetamol poisoning?

Answer 9

• 4-15h after single ingestion, level on or above treatment line
• >15h single ingestion, paracetamol still detectable (10+mg/L)
• >4h after last tablets of a staggered ingestion, paracetamol is detectable
• >4h after an ingestion of uncertain timing, paracetamol is detectable

Question 10

Outline the King’s College criteria for liver transplant in paracetamol poisoning

Answer 10

• pH <7.30
• INR >6.5 (PT >100s)
• Creatinine 3.4mg/dL
• Grade III or IV hepatic encephalopathy
  
  • III: Marked confusion; incoherent; responds to voice
  • IV: Coma; unresponsive to pain