Sodium Correction Rate Calculator for Hypo- and Hypernatremia

Q: Can rapid sodium correction lead to complications in hypernatremia?

Rapidly correcting high serum sodium levels can lead to severe complications, such as cerebral edema. This occurs due to the rapid movement of water from the bloodstream into cells, including brain cells, causing them to swell.

Q: What is the formula for the correction of sodium in hyponatremia?

To find the change in serum sodium, use: Change in serum sodium = (Fluid sodium - Serum sodium) / (TBW + 1) where: Fluid sodium is the sodium concentration in the fluid; Serum sodium refers to the serum sodium concentration; and TBW is the total body water. Then, determine the correction flow rate with the following: Correction flow rate = 1000 × Aimed change × (TBW + 1) / (Fluid sodium - Serum sodium) where: Aimed change is the desired hourly serum sodium change, considering overcorrection risk.

Creators

Małgorzata Koperska, MD and Mariamy Chrdileli

Mariamy Chrdileli

Mariam is a psychologist with a master’s degree in Clinical and Health Psychology from Eötvös Loránd University, Budapest. At New Vision University in Georgia, she supports international students as they navigate the challenges of academic life and personal well-being. When not conducting consultations, Mariam is likely hunting for the perfect plant to propagate or challenging herself at the gym. See full profile

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Bogna Szyk, Steven Wooding

Steven Wooding

Steven Wooding is a physicist by training with a degree from the University of Surrey specializing in nuclear physics. He loves data analysis and computer programming. He has worked on exciting projects such as environmentally aware radar, using genetic algorithms to tune radar, and building the UK vaccine queue calculator. Steve is now the Editorial Quality Assurance Coordinator here at Omni Calculator, making sure every calculator meets the standards our users expect. In his spare time, he enjoys cycling, photography, wildlife watching, and long walks. See full profile

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, Aleksandra Zając, MD

Aleksandra Zając

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Aleksandra (Ola) Zając, MD, is a medical doctor with a passion for lifestyle medicine. She wants to never stop learning while sharing what she already knows as a health educator and prophylaxis popularizer. She mainly concentrates on how human lifestyle impacts their health and disease. After hours, she likes weightlifting, foreign affairs podcasts, learning Korean, and dogs (with a special affection for her own pup Zoja). See full profile

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, and Adena Benn

Adena Benn

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Adena Benn is a Guyanese teacher with a degree in computer science who is always reading and learning. She loves problem-solving, everything tech, and working with teenagers. She has a passion for education and is especially interested in how children learn and the teaching methods that best suit their learning styles. She grew up on a farm in Pomeroon, Guyana, where she worked alongside her parents and siblings. As such, she is just as comfortable growing plants as teaching in the classroom. In her early life, she also gained expertise as a seamstress, which she learned from her mother. By grade 9, she had already acquired her dressmaker's certificate. Today she uses her skills to design many items for her family. In her free time, Adena loves to read, take long walks, write children’s stories and poetry, travel, or spend time with her family. See full profile

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New

The sodium correction rate calculator uses the patient's weight, serum sodium concentration, the aimed increase of serum sodium, and the chosen fluid's parameters to find the serum sodium change per liter and the rate of the sodium replacement fluid flow.

Come along to learn:

What sodium correction formula is used by our calculator;
How to go about calculating the sodium correction rate;
What is the recommended maximum rate of sodium replacement per day to treat hyponatremia safely; and
Much more.

You'll also probably find our water deficit, sodium deficit, sodium correction for hyperglycemia, and fractional excretion of sodium (FENa) calculators useful.

We try our best to make our Omni Calculators as precise and reliable as possible. However, this tool can never replace a professional doctor's assessment. All information on this website is for informational purposes only and is not intended as a substitute for medical consultation. Always consult your healthcare provider if you are unwell.

What's the rate of sodium correction formula?

The sodium correction rate calculator uses the Adrogue-Madias formula, as it is the one most widely used sodium correction formula in the prediction of serum sodium change:

change in serum sodium = (fluid_sodium - serum_sodium) / (TBW + 1)

where:

fluid_sodium is the concentration of sodium in the fluid you're planning to use. The values provided here are based on this table of the composition of commonly used crystalloids by the National Institute for Health and Care Excellence (NICE).
serum_Na is the measured concentration of sodium in the blood serum.
TBW is the total body water. We calculate this by multiplying the patient's weight by the age/sex coordinate, which equals 60% for children and adult males, 50% for adult females and elderly males, and 45% for elderly females. See the total body water calculator.

Then, to calculate the sodium correction rate, we use the inverse of the previous calculation:

correction flow rate = 1000 × aimed_change × (TBW + 1) / (fluid_sodium - serum_sodium),

where:

aimed_change is the aimed serum sodium change per hour. As there is a risk of overcorrection.

Keep in mind that rapid sodium correction may lead to cerebral edema or the development of osmotic demyelination, which may, in turn, result in brain damage or death.

Experts recommend that the sodium correction should not exceed 8 mmol/L/day. Remaining within this daily range, the initial correction rate in patients with severe symptoms can be 1 - 2 mEq/L/hr for several hours.

You should always check the results and the current guidelines with another healthcare provider, as the sodium replacement rate calculator cannot replace clinical judgment and medical assessment.

How do I use the calculator to calculate the sodium correction rate?

Choose the patient's age/sex group from the five options given in the first line: child, adult female, adult male, elderly female, and elderly male.
Type in the patient's weight in the preferred unit.
Enter the measured serum sodium level. If your results are in mmol/L, type in these values – in the case of sodium, they are equal to those in mEq/L.
Choose the kind of sodium replacement fluid you're planning to use.
The predicted serum sodium change per liter of administered replacement fluid is given in the second to last field in milliequivalents per liter (mEq/L), which is equal to millimoles per liter (mmol/L).
The calculated sodium correction rate is presented in the last field in milliliters per hour (ml/h).

FAQs

Can rapid sodium correction lead to complications in hypernatremia?

Rapidly correcting high serum sodium levels can lead to severe complications, such as cerebral edema. This occurs due to the rapid movement of water from the bloodstream into cells, including brain cells, causing them to swell.

How do I calculate total body weight for sodium correction rate in hyponatremia?

If you're trying to determine the sodium correction rate in hyponatremia, and you want to calculate the total body weight to use it in for the formula, you can follow these steps:

Take the weight of the patient in kg.
Multiply the weight by the percentage of body water according to the table below:

Age	Male	Female
Child	0.6	0.6
Adult	0.6	0.5
Elderly	0.5	0.45

That's it. You now have the total body weight for sodium correction rate in hyponatremia.

What is the formula for the correction of sodium in hyponatremia?

To find the change in serum sodium, use:

Change in serum sodium = (Fluid sodium - Serum sodium) / (TBW + 1)

where:

Fluid sodium is the sodium concentration in the fluid;
Serum sodium refers to the serum sodium concentration; and
TBW is the total body water.

Then, determine the correction flow rate with the following:

Correction flow rate = 1000 × Aimed change × (TBW + 1) / (Fluid sodium - Serum sodium)

where:

Aimed change is the desired hourly serum sodium change, considering overcorrection risk.

How do I correct sodium at 120 mEq/L in a patient?

To correct a sodium level of 120 mEq/L in a patient:

Determine the patient's age, sex, and weight;
Choose the appropriate sodium replacement fluid and rate of sodium correction; and
Apply the Adrogue-Madias formula.

For example, for an adult male (70 kg) using a 2% saline solution at a rate of 0.5 mEq/L/h, sodium correction would be 97 mL/h.

Sodium correction should only be performed by medical professionals in accordance with the patient's unique clinical circumstances.

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