Calculators
Formula-based ICU calculations — every result is computed locally in your browser, with no network calls and no patient data ever transmitted anywhere. Open a calculator for its full formula, interpretation, limitations, and references.
Respiratory
Grades hypoxemia severity using the 2012 Berlin ARDS oxygenation bands when PaO2/FiO2 is measured with PEEP/CPAP ≥5 cmH2O. The newer Global ARDS Definition also recognizes nonintubated ARDS on HFNO ≥30 L/min and additional pathways, so this calculator should not be used as the sole modern ARDS diagnostic tool.
Plateau pressure minus PEEP — a marker of lung-protective ventilation beyond tidal volume alone.
Tidal volume delivered per unit of driving pressure — a bedside marker of how stiff the lung and chest wall are.
Total volume of gas moved in or out of the lungs per minute.
Predicted body weight from height and sex (Devine formula) — the basis for lung-protective tidal volume dosing.
Target tidal volume for lung-protective ventilation, dosed to predicted body weight rather than actual weight.
Hemodynamics
Estimated average arterial pressure across the cardiac cycle, from systolic and diastolic pressure.
Heart rate divided by systolic blood pressure — a simple bedside marker that can flag early hemodynamic compromise before hypotension develops.
Acid-Base
Narrows the differential for a metabolic acidosis by estimating the concentration of unmeasured anions in the plasma.
How far the anion gap has risen above normal — the numerator used when assessing for a concurrent metabolic process.
Compares the rise in anion gap to the fall in bicarbonate, to detect a second metabolic process hiding behind a high-anion-gap acidosis.
Predicted respiratory compensation (expected PaCO2) for a primary metabolic acidosis.
Difference between measured and calculated osmolality — a screen for unmeasured osmotically active substances such as toxic alcohols.
Renal
Estimates creatinine clearance from age, weight, sex, and plasma creatinine — commonly used for renally-cleared drug dosing.
Calculates FeNa as a context-dependent physiologic clue in AKI; it can support but does not by itself distinguish hemodynamic/prerenal physiology from intrinsic kidney injury.
Calculates FeUrea, sometimes used as an adjunct when diuretics limit FeNa interpretation; FeUrea is also context-dependent and does not reliably distinguish prerenal physiology from intrinsic AKI by itself.
Estimates the water deficit underlying hypernatremia, as a starting point for correction planning.
Electrolytes
Estimates true serum sodium in the setting of hyperglycemia, which dilutes measured sodium by drawing water into the vascular space.