Predicting mortality from acetaminophen poisoning shortly after hospital presentation

Area of Science:

• Toxicology
• Clinical Medicine
• Public Health

Background:

• Acetaminophen (APAP) poisoning is a common cause of overdose.
• Early identification of patients at high risk of mortality from APAP poisoning is challenging.
• Established prognostic criteria vary in sensitivity and timeliness.

Purpose of the Study:

• To compare the sensitivity and time to fulfillment (latency) of established prognostic criteria for predicting in-hospital death after acetaminophen poisoning.
• To evaluate the effectiveness of criteria such as King's College Hospital (KCH), Model for End Stage Liver Disease (MELD), lactate, and phosphate levels.

Main Methods:

• Retrospective analysis of 162 in-hospital deaths from APAP overdose across eight Canadian cities over 30 years.
• Independent classification of deaths by three physician toxicologists using the Relative Contribution to Fatality scale.
• Calculation of sensitivity and latency for KCH, MELD ≥33, lactate ≥3.5 mmol/L, and phosphate ≥1.2 mmol/L criteria.

Main Results:

• Of 162 deaths, 93 were classified as "APAP deaths".
• King's College Hospital (KCH) or lactate criteria demonstrated the highest sensitivity (94%) and shortest latency (median 4.2 hours) for identifying APAP deaths.
• Model for End Stage Liver Disease (MELD) criterion showed lower sensitivity (55%) and longer latency (median 52 hours).

Conclusions:

• King's College Hospital (KCH) or serum lactate criteria are effective in identifying most patients who die from acetaminophen poisoning.
• These criteria facilitate early recognition and intervention for high-risk individuals.
• Lactate and KCH criteria offer a more timely and sensitive approach compared to MELD for predicting mortality in APAP overdose.