Osmolality Calculator

Medical Calculator – SonDoctor.com

Calculated Osm = (2 × Na) + (glucose / 18) + (BUN / 2.8)
Effective Osm = (2 × Na) + (glucose / 18)
(BUN crosses cell membranes freely and has minimal osmotic effect)
Osmolar gap = Measured Osm – Calculated Osm

Serum Sodium (mmol/L) :
Serum Glucose (mg/dL) :
Serum Urea (mg/dL) :
[Optional] Measured Serum Osmolality (mOsm/kg) :

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