Serum Osmolality

Calculates serum osmolality from sodium, glucose and BUN. Comparing it with a measured value reveals an osmolal gap suggesting unmeasured osmoles such as toxic alcohols.

What you enter

• Sodium (mEq/L)
• Glucose (mg/dL)
• BUN (mg/dL)

Reference

2Na + glucose/18 + BUN/2.8

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Educational decision-support tools. They do not replace clinical judgment, local protocols or specialist advice: verify results before acting on them.