Test Directory / Osmolality
Brown clotted serum, gel barrier
|Brown clotted serum, gel barrier
|Determination of serum and urine osmolality can be useful in the assessment of electrolyte and acid-base disorders. Comparison of serum and urine osmolalities can determine the status of renal water regulation in settings of severe electrolyte disturbances as might occur in diabetes insipidus or the syndrome of inappropriate anti-diuretic hormone. Osmolality may also be performed as part of a water deprivation test (used in the diagnosis of diabetes insipidus) or where there is suspicion of ingestion of an osmotically active substance such as ethanol, methanol or ethylene glycol.
|0.5mL If requesting more than 10 tests please send an additional brown clotted serum sample.
|No special requirements
|Serum: 4 days at room temperature and 8 days at 4°C Whole blood: 12 hours at room temperature and ? 14 days at 4°C
|Inpatient: 24 hours Outpatient/ GP: 24 hours
|York and Scarborough
|Additives, such as anticoagulants found in some collection containers, may contribute significantly to the measured osmolality and should NOT be used.