Osmolal gap

Osmolal Gap is the difference between measured serum osmolalityand calculated serum osmolality.

It is typically calculated as: OG = measureed serum osmolality - (2 X serum sodium+ serum glucose+ serum urea)

Where:

• 2 X serum sodium + serum glucose + serum urea = the calculated serum osmolality and all measures are in mmol/L.
• OG = osmolal gap

In US customary units the calculated osmolarity is: ( 2 x sodium ) + glucose/18 + BUN/2.8

A normal osmolal gap is < 12 mmol/L.

Causes of an elevated osmolal gap are numerous. Several causes are:

• ethanolintoxication
• methanolingestion
• ethylene glycolingestion

See also

• Osmolality
• Metabolic acidosis

External links

• Osmolar gap- fpnotebook.com
• Serum Osmolality- fpnotebook.com
• Acid-Base Physiology

This article is licensed under the GNU Free Documentation License.
It uses material from the http://en.wikipedia.org/wiki/Osmolal+gap Wikipedia article Osmolal gap.