Laboratory interpretation in the emergency department — the systematic high-yield read

Meet the patient

A man is found collapsed at home beside a bottle of car antifreeze. He is drowsy, breathing deeply and fast, and the bedside glucose is normal. A point-of-care lactate reads high while the automated chemistry lactate returns much lower.

This discordance is the lactate gap (point-of-care minus automated chemistry). Most point-of-care lactate results are falsely elevated in ethylene glycol poisoning, and an elevated lactate gap together with a high anion gap metabolic acidosis and an osmolar gap provides rapid surrogate laboratory data indicating ethylene glycol poisoning, enabling timely treatment while gas chromatography quantitation — rarely available — is awaited.^[18]

References38ShowHide

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