Sodium Change Calculator in Hypertriglyceridemia
Calculate true sodium levels corrected for pseudohyponatremia caused by elevated triglycerides
Calculate Sodium Correction
Normal range: 135-145 mEq/L
Normal: <150 mg/dL (<1.7 mmol/L)
Example Calculation
Patient with Severe Hypertriglyceridemia
Measured Sodium: 130 mEq/L (appears low)
Triglycerides: 800 mg/dL (very high)
Clinical Question: True hyponatremia or pseudohyponatremia?
Step-by-Step Calculation
Step 1: Sodium change = (800 - 150) / 1000 × 130
Step 2: Sodium change = 650 / 1000 × 130 = +8.45 mEq/L
Step 3: Corrected sodium = 130 + 8.45 = 138.5 mEq/L
Result: Normal corrected sodium - pseudohyponatremia confirmed
Normal Laboratory Values
Serum Sodium
135-145 mEq/L
Triglycerides
<150 mg/dL (<1.7 mmol/L)
Borderline High TG
150-199 mg/dL
High TG
200-499 mg/dL
Very High TG
≥500 mg/dL
Pseudohyponatremia Causes
Lipid-Related
- • Hypertriglyceridemia
- • Severe hyperlipidemia
- • Chylomicronemia
Protein-Related
- • Multiple myeloma
- • Waldenström's macroglobulinemia
- • IV immunoglobulin infusion
- • Hyperproteinemia
Other Causes
- • Mannitol infusion
- • Glycine irrigation
- • Severe hyperglycemia
Understanding Pseudohyponatremia in Hypertriglyceridemia
What is Pseudohyponatremia?
Pseudohyponatremia occurs when sodium levels appear low on laboratory tests, but the actual concentration in plasma water is normal. This happens when elevated lipids or proteins displace water in the plasma sample, affecting the measurement.
Clinical Significance
- •Prevents inappropriate sodium replacement therapy
- •Avoids potentially harmful treatments
- •Guides appropriate lipid management
- •Identifies underlying metabolic disorders
Mechanism of Action
Normal Plasma: ~93% water, ~7% solids (proteins, lipids)
Hypertriglyceridemia: Increased lipid volume reduces water fraction
When triglycerides are elevated, they occupy more plasma volume, reducing the water fraction. Since sodium is measured per total plasma volume, the apparent concentration decreases even though the actual concentration in plasma water remains normal.
Treatment Implications
Correcting pseudohyponatremia requires treating the underlying lipid disorder rather than sodium replacement. Inappropriate sodium therapy can lead to true hypernatremia.