Which factors influence postoperative ventilation strategies after CABG?

• A. CPB-related lung injury, atelectasis risk, edema, and gas exchange; strategies include lung-protective ventilation, appropriate PEEP, and early mobilization
• B. Only age matters
• C. Ventilation is always standard
• D. Nutrition dictates ventilation

Answer: (D)

Postoperative ventilation after CABG is guided by the lung effects of cardiopulmonary bypass and the resulting risk of collapsed airways, edema, and impaired gas exchange. CPB often triggers inflammatory changes and surfactant dysfunction, making the lungs stiffer and more prone to atelectasis. The ventilatory plan therefore aims to protect the lungs while ensuring adequate oxygenation and carbon dioxide removal. This means using lung-protective settings—lower tidal volumes based on predicted body weight, keeping plateau pressures within safe limits, and applying enough PEEP to keep alveoli open without overdistending the lungs. Recruitment maneuvers can be used selectively to reopen collapsed units, alongside careful fluid management to minimize edema. Encouraging early mobilization and pulmonary toilet helps expand the lungs, improve ventilation-perfusion matching, and hasten weaning from the ventilator. Nutrition supports overall recovery but does not determine the ventilatory strategy, and age alone does not dictate the approach; the ventilation plan is tailored to the patient’s lung mechanics and gas exchange status.