Measured serum sodium
Serum triglycerides
Sodium change
Corrected serum sodium

Sodium Change Calculator in Hypertriglyceridemia

By Aleksandra Zając, MD

This sodium change calculator helps you find the real sodium concentration in a patient with hypertriglyceridemia. Patients suffering from hypertriglyceridemia may present a decreased level of serum sodium. This is a common example of pseudohyponatremia - when a patients true serum sodium concentration is higher than that seen on paper. This is not the only example, though - check out the causes of pseudohyponatremia for more information.

We try our best here at Omni to make our calculators as precise and reliable as possible. However, this tool can never replace a professional doctor's assessment. Before administering any drug, fluid, or treatment to your patient, make sure you know the correct dose and method.

Sodium in hypertriglyceridemia

When we look at the results of a laboratory test, we usually feel quite sure that the numbers and results we're seeing are correct. We rely on modern lab machines and the professionalism of our diagnosticians, so the results that we see much support our diagnosis - right? Unfortunately, even the most thorough lab tests can be incorrect. Thus, it's worth having some knowledge of how one parameter can influence others, the mechanism behind it, and how we can deal with it.

One such example is serum sodium concentration, often measured during a standard hospital stay. The most common sodium disorder, hyponatremia, affects betweens 2-3% of all hospitalised patients, and causes psychiatric-like symptoms, followed by a sudden improvement after their ion levels get back to normal.

Sodium is a labile ion. If your serum protein, lipid, or sugar concentration is higher than usual- sodium will react. In this sodium change calculator we deal with the case of how sodium levels change in a patient with hypertriglyceridemia. In this case, sodium levels are often higher than the lab report shows - this is a state we call pseudohyponatremia (and triglycerides are not the only reason - check out the other pseudohyponatremia causes here). High blood sugar levels require sodium correction as well - remember this when admitting diabetes patients.

Pseudohyponatremia phenomenon

While regular hyponatremia means that a patients sodium (Na) serum concentration is lower than 135mEq/L (normal range is 135-145mEq/L), pseudohyponatremia - or false hyponatremia - occurs when a patients Na levels are within the normal range, but, for some reason, the laboratory tests show a lowered value.

How does this happen? Sodium concentration is measured by dividing the sodium content by the plasma volume. Plasma is made of plasma water, proteins, and lipids (i.e., water and solid particles).

Plasma volume = Plasma water + proteins + lipids

Sodium concentration = Sodium/Plasma volume

Usually, the volume of solid particles in the serum is negligible and doesn't really affect the result of the lab test. In certain physiological states, the amount of proteins or lipids increases, thus increasing the plasma volume. As a result, the sodium concentration seems small, while, in actuality, its concentration in the plasma water is normal.

True hyponatremia is associated with low osmolality and causes free water move into cells, where the osmolality is higher. On the other hand, pseudohyponatremia is not connected with low osmolality and free water stays outside the cells, or even moves out of them.

How to use the sodium change calculator

The only data you need to know is the result of two laboratory tests: the concentration of triglycerides in serum and the serum sodium (Na+) concentration.

  1. In the first row of the sodium change calculator, input the serum sodium concentration as given in the lab test report.
  2. In the second row you will find a place for triglycerides. You can freely switch between units - either mg/dL or mmol/L.
  3. The next field shows the change in your patient's serum sodium level- in case of severe hypertriglyceridemia, it can astonish you!
  4. The last row does the maths for you - it adds the measured sodium and the change in sodium to presents you with the real serum sodium concentration.

Pseudohyponatremia causes

Pseudohyponatremia causes include states of increased triglycerides or proteins (respectively hypertriglyceridemia and hyperproteinemia). Medical conditions that lead to these states, or can combine with them, are:

  • hyperlipidemia - specifically hypertriglyceridemia
  • multiple myeloma
  • Waldenström's macroglobulinemia
  • IV infusion of immunoglobulins
  • extremely rarely - hypercholesterolemia

It is important to remember those conditions when you see a patient with hyponatremia. Supplementing sodium in a patient with pseudohyponatremia can lead to severe health consequences.

Aleksandra Zając, MD