Osmolality (Serum)

Pathology category

Biochemistry

Code

OS

Referral code

Request form

Test information

Assessment of osmolality, most commonly used in hyponatraemic patients, or patients with raised glucose, or suspected of high serum alcohol levels.

NOTE: If required for water deprivation test, please request as WDEP and inform the lab 24h prior to test so they can be processed urgently

Guidelines

Pre-analytical

NOTE: If required for water deprivation test, please request as WDEP and inform the lab 24h prior to test so they can be processed urgently

Reference range

275-295 mosmol/Kg

Tube type

Tube type info

SST

Special requirements

Serum

Minimum volume

Assay frequency

TAT Inpatient (urgent)

TAT Inpatient

4 hrs

TAT GP/Outpatient

48 hrs

Referral lab

Local, Clinical Biochemistry