Calculator ng Tidal Volume (ARDSNet)

Clinical Principles of Lung-Protective Mechanical Ventilation

Prior to the year 2000, intensive care units routinely ventilated patients with acute respiratory failure at high tidal volumes (10–15 mL/kg). In 2000, the Acute Respiratory Distress Syndrome Network (ARDSNet) published the landmark ARMA trial in the New England Journal of Medicine, establishing that lower tidal volume ventilation targeting 6 mL/kg PBW dramatically decreases mortality and increases ventilator-free days.

Predicted Body Weight (PBW) Formulas

Because thoracic dimensions correlate with skeletal height rather than body mass index (BMI):

• Males (cm): PBW (kg) = 50 + 0.91 × (Height in cm - 152.4)
• Males (inches): PBW (kg) = 50 + 2.3 × (Height in inches - 60)
• Females (cm): PBW (kg) = 45.5 + 0.91 × (Height in cm - 152.4)
• Females (inches): PBW (kg) = 45.5 + 2.3 × (Height in inches - 60)

Ventilator setting – calculation example

Let’s see an example calculation for an adult male measuring 5 ft 10 in (70 inches / 178 cm):

1. Select patient sex: sex = Male.
2. Enter patient height: height = 70 inches (178 cm).
3. The calculation results are available for you: Predicted Body Weight (PBW) = 73.0 kg.
4. Initial ARDSNet protective target: 6 mL/kg PBW = 438 mL.
5. Safe protective range: 4 to 8 mL/kg PBW = 292 to 584 mL.

💡 Ventilator tidal volumes should always be calibrated to PBW (lung size) rather than actual total weight to avoid barotrauma in patients with elevated BMI.

Ventilator Target Ranges by Clinical Protocol

Clinical Note: This tool is intended for medical education and reference. Ventilator settings must always be individualized based on arterial blood gas (ABG) values, plateau airway pressures, and patient clinical status.