When aiming to improve oxygenation while minimizing ventilator-induced lung injury, the main levers are the amount of oxygen you deliver and keeping the lungs open at end expiration. PEEP (positive end-expiratory pressure) helps keep alveoli from collapsing, increases surface area for gas exchange, reduces shunt, and makes oxygen transfer more efficient. FiO2, the fraction of inspired oxygen, directly raises the amount of oxygen in the air the patient breathes, helping to boost blood oxygen levels. Using these together lets you achieve target oxygenation with lower risks of injury from high pressures or large tidal volumes. Tidal volume is more about removing CO2 and the risk of volutrauma; increasing it to improve oxygenation can worsen lung injury. Sigh rate is a less direct way to recruit airways and can cause overdistension if used inappropriately, while inspiratory flow rate mainly affects the shape of the inspiration and is not the primary tool for improving oxygenation.