This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.

• Fluid calculator

  Holliday-Segar maintenance requirement, 24-hour plan for dehydration and volume bolus by AWMF 068-003

• Urine output ml/kg/h

  From urine volume, weight and collection time – with the oliguria stages according to KDIGO (children and neonates)

• Fluid balance

  Intake minus output over a period – with urine output in ml/kg/h and balance in % of body weight

• Free water deficit

  In hypernatremia: water deficit from sodium, weight and total body water fraction, with correction limit

• Sodium deficit

  In hyponatremia: sodium deficit, infusion volume according to Adrogué-Madias and correction limits of the guideline

• Corrected sodium in hyperglycemia

  Sodium according to Katz (1.6) and Hillier (2.4) per 100 mg/dl glucose above 100

• Sodium correction rate

  Actual change in sodium from two measurements – compared with the guideline limits

• Potassium intake / potassium replacement

  Maintenance requirement, oral and intravenous replacement per kg with maximum rates and concentrations (Daly & Farrington 2013)

• Bicarbonate deficit

  Volume of distribution × kg × (target − actual) – with selectable volume of distribution 0.3–0.5

• Serum osmolality

  Calculates from sodium, glucose and urea/BUN – conventional or SI

• Effective osmolality (tonicity)

  2 × sodium + glucose – the osmotically effective osmolality without urea

• Osmolal Gap

  Measured minus calculated osmolality – with ethanol correction (Purssell 2001)

• Anion gap

  Na − (Cl + HCO₃), optionally with potassium – reference range according to Kraut & Madias

• Albumin-corrected Anion Gap

  AG + 2.5 × (4.0 − albumin g/dl) according to Figge 1998

• Delta gap

  Anion gap minus 12 – rise in the anion gap relative to the reference value and comparison with the bicarbonate decrease

• Delta ratio

  (AG − 12) ÷ (24 − HCO₃) – assessment of mixed acid–base disorders

• Corrected calcium

  Albumin-corrected total calcium according to Payne – mg/dl or mmol/l

• Winter's formula

  Expected pCO₂ in metabolic acidosis: 1.5 × HCO₃ + 8 ± 2

• Acid-base compensation calculator

  Primary disorder from pH, pCO₂ and HCO₃ – expected compensation according to Berend 2014 and anion gap

← All calculators at a glance