Paracetamol poisoning: which nomogram should we use?

Area of Science:

• Emergency Medicine
• Clinical Toxicology

Background:

• Paracetamol (acetaminophen) overdose is a common cause of acute liver injury.
• Nomograms are crucial tools for guiding N-acetylcysteine treatment in paracetamol poisoning.
• Current guidelines and practices for paracetamol nomogram use in Australasia require evaluation.

Purpose of the Study:

• To determine the types of paracetamol nomograms currently utilized in Australasian Emergency Departments (EDs).
• To review the existing scientific literature for the evidence base supporting current paracetamol nomogram guidelines.

Main Methods:

• A cross-sectional descriptive study was conducted using a postal survey of all Australasian EDs accredited for specialist emergency medicine training.
• A comprehensive literature review was performed utilizing the Knowledge Finder search engine.

Main Results:

• The study achieved an 87% response rate from Australasian EDs.
• The most frequently adopted nomogram featured a four-hour treatment threshold of 1300 mumol/L (used by 69% of respondents).
• Significant variation exists, with 22% using a 1000 mumol/L threshold, 3% treating above 660 mumol/L, and 15% lacking a treatment line below 1300 mumol/L.

Conclusions:

• There is considerable variability in paracetamol nomogram use across Australasian EDs.
• Literature indicates that hepatotoxicity and fatalities can occur in patients with paracetamol levels below the 1300 mumol/L threshold.
• N-acetylcysteine remains a highly safe and effective antidote when administered at recommended dosages.