Amount of required sodium replenishment for the patient with hyponatremia
Hyponatremia is a common electrolyte disturbance frequently requiring fluid administration for correction to physiologic levels. Rapid correction can be dangerous for patients, leading to cerebral edema and osmotic demyelination among other complications.1 Determining a safe rate of fluid administration to prevent these issues relies on patient and fluid variables. The majority of cases of osmotic demyelination were originally thought to have taken place with daily sodium correction of greater than 12 mmol/L/day (0.5 mmol/L/hr); however, many experts advocate for a more conservative approach to correction, targeting 4-6 mmol/L/day with a maximum of 8 mmol/L/day.2
This calculator specifically addresses the total sodium deficit for a patient considering their total body water (TBW) alongside current and desired serum sodium levels. The calculation used for TBW is simplified, however many more complex equations integrating age and height exist in the literature.
Calculator for Sodium Deficit
Sodium Deficit (mEq) = Total body water (TBW) * (Desired sodium - Serum sodium
Whereby:
Hyponatremia is a common electrolyte disturbance frequently requiring fluid administration for correction to physiologic levels. Rapid correction can be dangerous for patients, leading to cerebral edema and osmotic demyelination among other complications.1 Determining a safe rate of fluid administration to prevent these issues relies on patient and fluid variables. The majority of cases of osmotic demyelination were originally thought to have taken place with daily sodium correction of greater than 12 mmol/L/day (0.5 mmol/L/hr); however, many experts advocate for a more conservative approach to correction, targeting 4-6 mmol/L/day with a maximum of 8 mmol/L/day.2
This calculator specifically addresses the total sodium deficit for a patient considering their total body water (TBW) alongside current and desired serum sodium levels. The calculation used for TBW is simplified, however many more complex equations integrating age and height exist in the literature.
Calculator for Sodium Deficit
Sodium Deficit (mEq) = Total body water (TBW) * (Desired sodium - Serum sodium
Whereby:
© 2020 QxMD Software Inc., all rights reserved. No part of this service may be reproduced in any way without express written consent of QxMD. This information should not be used for the diagnosis or treatment of any health problem or disease. This information is not intended to replace clinical judgment or guide individual patient care in any manner. Click here for full notice and disclaimer.
