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Equations

Scores

Serum Osmolality

  Units: US SI
Na mEq/L
K mEq/L
BUN mg/dL
Glucose mg/dL
Serum Osmolality mOsm/kg
Normal serum osmolality = 285-295 mOsm/kg

Serum Osmolality (US) = (2 * (Na + K)) + (BUN / 2.8) + (glucose / 18); SI units ares all molar, so no need to divide by 2.8 or 18.