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  Water Deficit in Hypernatremia

Age Sex Factor Male <65 years old (0.6)

Male ≥65 years old (0.5)

Female <18 years old (0.6)

Female 18-65 years old (0.5)

Female ≥65 years old (0.45)
Desired Na  
Normal Weight  
Serum Na  

Decimal Precision  

Include literature references: Yes   No
  • The default unit of measure for weight is kilograms. Please verify that the correct unit of measure has been selected.
  • The term Age Sex Factor * Normal Weight represents the normal total body water (TBW).
  • Normal TBW is gender and age specific as seen in the 0.6, 0.5 and 0.45 factors above.

Equations used
WDef = (AgeSexFactor * NormalWeight) * (SerumNa - DesiredNa) / DesiredNa


Calculation Details and Variables
  • Equation parameters such as Age Sex Factor, have two or more discrete values that may be used in the calculation. The numbers in the parentheses, e.g. (0.6), represent the values that will be used.

  1. Adrogue HJ, Madias NE. Hypernatremia. N Engl J Med. 2000 May 18;342(20):1493-9. PubMed ID: 10816188 PubMed Logo

Associated Medical Subject Headings [MeSH]
         Female,   Humans,   Hypernatremia,   Insensible,   Male,   Water Loss,   Water-Electrolyte Imbalance

Associated Logical Observation Identifiers Names and Codes [LOINC]
Parameter LOINC's and Suggested Units
Serum Na 2951-2 : mmol/L      2947-0 : mEq/L      32340-2 : mEq/L      39791-9 : mEq/L      

This material contains content from LOINC® (http://loinc.org). The LOINC table, LOINC codes, and LOINC panels and forms file are copyright © 1995-2014, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and available at no cost under the license at http://loinc.org/terms-of-use.

Associated ICD10-CM Codes
   E87.0Hyperosmolality and hypernatremia
   E87.8Other disorders of electrolyte and fluid balance, not elsewhere classified

Associated ICD9-CM Codes
   276.9Electrolyt/fluid dis nec

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