Osmolality – Serum – BC250
💧 Fluid & Electrolyte Balance
₹599
MRP ₹690
Sample Time: 4:30 PM
Report: Next day Evening
Sample Type: Blood (Serum)
Test Code: BC250
Report: Next day Evening
Sample Type: Blood (Serum)
Test Code: BC250
About this Test:
The Serum Osmolality test measures the concentration of dissolved particles (solutes) in your blood. These particles include sodium, glucose, and urea. This test is the most accurate way to assess your body's water balance.
✔ Crucial for investigating Hyponatremia (low sodium) and Hypernatremia (high sodium).
✔ Helps diagnose dehydration or overhydration.
✔ Used to detect the ingestion of toxins like methanol or ethylene glycol (via the Osmolal Gap).
✔ Often compared with Urine Osmolality to check kidney function.
The Serum Osmolality test measures the concentration of dissolved particles (solutes) in your blood. These particles include sodium, glucose, and urea. This test is the most accurate way to assess your body's water balance.
✔ Crucial for investigating Hyponatremia (low sodium) and Hypernatremia (high sodium).
✔ Helps diagnose dehydration or overhydration.
✔ Used to detect the ingestion of toxins like methanol or ethylene glycol (via the Osmolal Gap).
✔ Often compared with Urine Osmolality to check kidney function.
Why Measure Particle Concentration?
Your body strives to maintain a specific balance of water and dissolved substances (electrolytes, sugars, proteins) in the blood. Osmolality tells doctors exactly how concentrated or diluted your blood is. Sodium is the main contributor to serum osmolality, followed by glucose and urea.
What Abnormal Results Mean
- High Osmolality: This usually means the blood is too concentrated. Common causes include:
- Dehydration (loss of water).
- High blood sugar (hyperglycemia/diabetes).
- High sodium levels (hypernatremia).
- Build-up of toxins like alcohol or poisons.
- Low Osmolality: This means the blood is too diluted (too much water). Causes include:
- Overhydration (drinking too much water).
- Low sodium levels (hyponatremia).
- Syndrome of Inappropriate Antidiuretic Hormone (SIADH).
Doctors also calculate the Osmolal Gap. This is the difference between the measured osmolality (from this test) and the calculated osmolality (using a formula based on sodium, glucose, and urea). A large gap suggests the presence of hidden toxins like methanol or ethylene glycol.
Frequently Asked Questions (FAQ)
Q1: What is Osmolality?
Osmolality is a measure of the number of dissolved particles in a fluid. In blood, it reflects the balance between water and solutes like sodium and glucose.
Osmolality is a measure of the number of dissolved particles in a fluid. In blood, it reflects the balance between water and solutes like sodium and glucose.
Q2: Why did my doctor order this test?
It is commonly ordered if you have seizures, confusion, or signs of severe dehydration. It helps doctors investigate low sodium levels (hyponatremia) or suspect ingestion of toxins (like antifreeze or methanol).
It is commonly ordered if you have seizures, confusion, or signs of severe dehydration. It helps doctors investigate low sodium levels (hyponatremia) or suspect ingestion of toxins (like antifreeze or methanol).
Q3: Do I need to fast for this test?
Fasting is not strictly required, but doctors may advise you to avoid alcohol for 24 hours before the test, as alcohol can affect the results. Follow your doctor's specific instructions.
Fasting is not strictly required, but doctors may advise you to avoid alcohol for 24 hours before the test, as alcohol can affect the results. Follow your doctor's specific instructions.
Q4: What is the difference between Serum and Urine Osmolality?
Serum osmolality checks the blood's concentration, while urine osmolality checks the urine's concentration. Doctors often look at both simultaneously to see if the kidneys are properly conserving or excreting water to keep the blood balanced.
Serum osmolality checks the blood's concentration, while urine osmolality checks the urine's concentration. Doctors often look at both simultaneously to see if the kidneys are properly conserving or excreting water to keep the blood balanced.
Q5: What is the Osmolal Gap?
The Osmolal Gap is the difference between the measured osmolality (from this lab test) and the calculated osmolality (a math formula). A high gap indicates there are hidden particles in the blood, often due to toxins.
The Osmolal Gap is the difference between the measured osmolality (from this lab test) and the calculated osmolality (a math formula). A high gap indicates there are hidden particles in the blood, often due to toxins.