Select a hand-drawn equation page. Calculators are grouped by clinical topic.
Alveolar Oxygen Tension
Board Review Alveolar–Arterial Gradient
Arterial to Alveolar Ratio
Board Review PaO₂ / FiO₂ Ratio
Desired PaO₂ / FiO₂ Needed Estimate
FiO₂ from Two Gas Sources
O₂:Air Entrainment Ratio and Total Flow
Dalton’s Law of Partial Pressure
Partial Pressure of a Dry Gas
Density of Gases
Fick’s Law of Diffusion
Graham’s Law Diffusion Coefficient
Combined Gas Law
Boyle’s Law
Gas Volume Corrections
Board Review Heliox Flow Correction
Humidity Deficit
Relative Humidity
Board Review Oxygen Index (OI)
Oxygen Duration for Liquid System
Oxygen Cylinder Duration
Board Review
Airway Resistance
Board Review Static Compliance
Board Review Dynamic Compliance
Board Review Total Compliance
Corrected Tidal Volume
Board Review Physiologic Deadspace to Tidal Volume Ratio
Dead Space and Alveolar Ventilation
Endotracheal Tube Size for Children
Flow Rate in Mechanical Ventilation
Inspiratory to Expiratory Ratio
Board Review Lung Volumes and Capacities
Mean Airway Pressure
Board Review Minute Ventilation
Minute Ventilation Estimation
Minute Ventilation in IMV/SIMV
Ventilator Frequency or VE Estimate for Desired PaCO₂
Pressure Support Ventilation Setting
Tidal Volume Based on Flow and I Time
Poiseuille Equation
Reynolds Number
Rapid Shallow Breathing Index
Artificial Airway Catheter Size
Cardiac Index
Cardiac Output by Fick Equation
Mean Arterial Pressure
Cerebral Perfusion Pressure
Systolic minus Diastolic Pressure
Pulmonary Vascular Resistance
Systemic Vascular Resistance
Stroke Volume
Stroke Volume Index
Left Ventricular Stroke Work
Left Ventricular Stroke Work Index
Right Ventricular Stroke Work
Right Ventricular Stroke Work Index
Oxygen Consumption
Arterial Oxygen Content
End-Capillary Oxygen Content
Mixed Venous Oxygen Content
Arterial–Mixed Venous O₂ Content Difference
Oxygen Extraction Ratio
Classic Physiologic Shunt Equation
Estimated Shunt Equation