bih.button.backtotop.text
BROWSE BY TEST NAME
%
1
2
3
5
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Clear
 
Test Code:
OSMOLALITY

Order Name:
Osmolality (Serum)

 
Useful For:
Evaluating acutely ill or comatose patients
 
Methodology:
Freezing Point Depression
 
 
 
Test Code:
OSMOLALITY

Order Name:
Osmolality (Serum)

 
Collection Specimen Or Container:
Blood/ Plain blood (Red top) 6 mL, 1 tube
 
Specimen Testing Type:
Serum, minimum volume 0.5 mL
 
Sub Mission Container:
Plastic vial
 
Rejection Criteria:
Hemolysis: Mild OK
 
Specimen Stabillity:
Specimen Type Temperature Time
Serum Refrigerated, 2oC to 8oC 7 days
Frozen, -20o 7 days
 
 
 
Test Code:
OSMOLALITY

Order Name:
Osmolality (Serum)

 
Method detail:
Freezing Point Depression
 
Schedule:
Tested daily (24 hours)
 
Turnaround Time:
Collected specimen to report within 1.5 hours (90 mins)
 
Performing Location:
Chemistry, Laboratory Department Tel. 13224
 
Specimen Retention Time:
5 days
 
 
 
Test Code:
OSMOLALITY

Order Name:
Osmolality (Serum)

 
 
Clinical Information:
Osmolality is a measure of the number of dissolved solute particles in solution. It is determined by the number and not by the nature of the particles in solution. Dissolved solutes change the physical properties of solutions, increasing the osmotic pressure and boiling point and decreasing the vapor pressure and freezing point.

The osmolality of serum increases with dehydration and decreases with overhydration. The patient receiving intravenous fluids should have a normal osmolality. If the osmolality rises, the fluids contain relatively more electrolytes than water. If the osmolality falls, relatively more water than electrolytes is being administered.

Normally, the ratio of serum sodium, in mEq/L, to serum osmolality, in mOsm/kg, is between 0.43 and 0.5. The ratio may be distorted in drug intoxication.

Generally, the same conditions that decrease or increase the serum sodium concentration affect the osmolality.
 
Reference Value:
275 - 295 mOsmo/ kgH2O
 
Interpretation:
An increased gap between measured and calculated osmolality may indicate ingestion of poison, ethylene glycol, methanol, or isopropanol.
 
Clinical Reference:
http://www.mayomedicallaboratories.com (Retrieved: 01 Jan 2019)