Which patient is being adequately ventilated?

In the context of adequate ventilation, the scenario involving the 4-month-old girl is the best illustration of effective breathing. Adequate ventilation is indicated by the movement of the chest during breath delivery, demonstrating that air is reaching the lungs effectively.

In this circumstance, chest movement signifies that the girl is receiving sufficient air, as her respiratory system is functioning properly to allow for adequate gas exchange. Additionally, her starting to move around suggests increasing levels of consciousness and possibly adequate oxygenation and perfusion, further confirming that her body is responding positively to ventilation.

In contrast, the other scenarios indicate issues with ventilation. The girl who is pale and cyanotic with no chest movement suggests inadequate ventilation and potential respiratory failure. The 72-year-old male whose abdomen is distending while the chest remains still indicates improper ventilation mechanics, typically seen in cases like diaphragmatic breathing where the chest is not moving. Lastly, the 28-year-old male with no chest movement and difficulty ventilating is a critical sign of inadequate air exchange, pointing to severe respiratory distress or failure. These signs collectively highlight the importance of chest movement as a key indicator of effective ventilation.