Lactic acidosis can be a predictor for the severity of an acetaminophen (paracetamol) poisoning.
Basis: mitochondrial inhibition by the metabolite N-acetyl-p-benzo-quinone-imine (NAPQI)
Advantage: it may be more readily accessible than serum acetaminophen concentrations
Indications for measuring serum lactic acid for a patient with an acetaminophen overdose:
(1) intake known to be significant
(2 presence of a reduced level of consciousness or hepatic failure
Rules:
(1) A high serum lactate concentration within 8 hours of ingestion indicates a significant overdose.
(2) A high serum lactate is associated with increased mortality in patients who develop toxic hepatitis.
(3) The possibility of acetaminophen poisoning should be in the differential diagnosis of acute metabolic acidosis of unknown cause.
