Failure of Risk Assessment After Paracetamol Overdose-A Short Communication

Ther Drug Monit. 2023 Apr 1;45(2):273-276. doi: 10.1097/FTD.0000000000000995.

Abstract

Background: The accepted treatment for patients with acetaminophen/paracetamol overdose includes risk assessment based on the Rumack-Matthew (R-M) nomogram. An inaccurate use of the nomogram may result in improper treatment. Clinicians were surveyed to determine their understanding and proper use of this risk assessment tool in practice.

Methods: Differences between visual risk assessment using the same depiction of the R-M nomogram and calculated risk assessment were determined using an online calculator developed based on the Rumack equation. An online survey was administered in French between August 25, 2021, and November 25, 2021, as a Google Form with 14 questions (the paracetamol concentration and time postingestion were stated). A total of 147 respondents with an average age of 32 years (range 23-61 years) performed risk assessment (low/possible/probable/not assessable). The mean assessment accuracy was 66.2 ± 26.7% (12.3-99.3). The sensitivity, specificity, positive predictive value, and negative predictive value were 93%, 55%, 71%, and 89%, respectively. A subcohort of n = 31 senior clinicians showed the same trends (91%, 52%, 69%, and 84%).

Results: Approximately 7% of patients who are at risk of hepatotoxicity based on the R-M nomogram would not be treated. By contrast, N-acetylcysteine was not recommended by the R-M nomogram but would be administered to approximately 50% of patients. A concern for the latter group is that anaphylactoid reactions occur in up to 25% of patients with low paracetamol concentrations.

Conclusions: Some patients may be undertreated, resulting in possible hepatotoxicity, and many patients may be overtreated, resulting in a high percentage of anaphylaxis. Rather than relying on visual risk assessment, physicians should use an online calculator ( www.hopitox.com/?lang=en ) or consult with a toxicologist or poison center to substantially improve patient care after acetaminophen/paracetamol overdose.

MeSH terms

  • Acetaminophen
  • Adult
  • Analgesics, Non-Narcotic* / therapeutic use
  • Chemical and Drug Induced Liver Injury* / etiology
  • Drug Overdose*
  • Drug-Related Side Effects and Adverse Reactions*
  • Humans
  • Middle Aged
  • Retrospective Studies
  • Risk Assessment
  • Young Adult

Substances

  • Acetaminophen
  • Analgesics, Non-Narcotic