What does a plateau pressure of 46 cm H2O indicate in a ventilated patient?

A plateau pressure of 46 cm H2O suggests that there may be over-distension of the lungs, which can occur when the alveoli are being over-inflated or when there is a decrease in lung compliance. In a ventilated patient, this elevated plateau pressure is concerning because it can indicate that the lungs are either stiff (due to conditions such as ARDS or fibrosis) or that the tidal volume being delivered is too high for the lungs to handle comfortably.

When plateau pressures rise above normal levels, which typically range around 30 cm H2O in mechanically ventilated patients, this can signal potential injury to lung tissues. Excessive pressures can lead to barotrauma, volutrauma, and impaired gas exchange, which could worsen the patient's condition. Monitoring plateau pressure is essential to ensure that ventilation strategies are effective but also safe for the lung parenchyma.

The other options do not directly tie to the implications of a high plateau pressure. Improvement in oxygenation (option B) is not indicated by plateau pressure alone; it may or may not occur depending on various factors such as perfusion and ventilation balance. Effective tidal volume delivery (option C) does not correlate with elevated plateau pressures, as instead a high plateau indicates potential