Osmolality Calculated Serum Low Calculator
Osmolality calculated serum low is a critical parameter in clinical chemistry, reflecting the number of osmoles of solute per kilogram of solvent in a solution. Understanding and calculating serum osmolality is essential for diagnosing and managing various medical conditions.
- Enter the serum osmolality value in milliosmoles per kilogram (mOsm/kg).
- Enter the blood urea nitrogen (BUN) level in milligrams per deciliter (mg/dL).
- Optionally, enter the glucose level in milligrams per deciliter (mg/dL).
- Click the “Calculate” button to see the results and chart.
The formula used in this calculator is based on the following equation:
Serum Osmolarity = 2 * [Na+] + [Glucose] + [BUN] / 2.8
Where:
- [Na+] is the serum sodium concentration (mEq/L).
- [Glucose] is the serum glucose concentration (mg/dL).
- [BUN] is the blood urea nitrogen concentration (mg/dL).
| Serum Osmolarity (mOsm/kg) | Serum Osmolality (mOsm/kg) |
|---|---|
| 270 | 275 |
| 285 | 290 |
| 300 | 305 |
| Age | Lower Limit (mOsm/kg) | Upper Limit (mOsm/kg) |
|---|---|---|
| 0-1 year | 250 | 290 |
| 1-18 years | 260 | 290 |
| 18+ years | 270 | 290 |
- Always use fresh, properly collected, and handled blood samples for accurate results.
- Consider other factors like temperature, hydration status, and medications when interpreting osmolality results.
- Consult with a healthcare professional for personalized medical advice.
What is the difference between serum osmolality and serum osmolarity?
Serum osmolality and serum osmolarity are closely related but not identical. Osmolality is the number of osmoles of solute per kilogram of solvent, while osmolarity is the number of osmoles of solute per liter of solution. The main difference lies in the denominator: mass (kg) for osmolality and volume (L) for osmolarity.
What are the normal ranges for serum osmolality?
The normal range for serum osmolality is typically 270-290 mOsm/kg in adults. However, this can vary depending on age, hydration status, and other factors.