Lung-protective ventilation sets tidal volume from a patient's ideal body weight — not their actual weight — to keep breaths small enough to avoid injuring the lungs in ARDS.
Given: male, 170 cm (66.9 in), 6 mL/kg.
50 + 15.9 ≈ 65.9 kgTidal volume is scaled to lung size (height-based ideal body weight), targeting 4–8 mL/kg.
Lung size tracks height, not fat mass. Using ideal body weight (from height and sex) keeps breaths appropriately small even in obese patients, preventing overdistension of normal-sized lungs.
ARDSnet aims to keep plateau pressure at or below 30 cmH₂O. If it stays high at 6 mL/kg, tidal volume is reduced toward 4 mL/kg.
Ideal body weight = 50 kg (male) or 45.5 kg (female) + 2.3 kg for each inch over 5 feet. It's the standard basis for lung-protective tidal volume.
Yes — the ARDSnet trial showed lower tidal volumes (6 mL/kg) reduced mortality in ARDS compared with traditional larger volumes.