A 2-week-old infant on pressure control ventilation needs a decrease in PaCO2. What should the specialist increase?

In the context of a 2-week-old infant on pressure control ventilation who needs a decrease in PaCO2, it is important to understand how ventilation parameters influence gas exchange. Increasing the respiratory rate is a key action in this scenario because it allows for more frequent breaths, leading to enhanced removal of carbon dioxide (CO2) from the lungs.

Higher respiratory rates increase the frequency of ventilation, which directly enhances alveolar ventilation. Since PaCO2 is determined by the balance between carbon dioxide production and elimination, increasing respiratory rate effectively promotes the elimination of CO2, thereby reducing its partial pressure in the blood.

Tidal volume could also influence CO2 levels, but in pressure control ventilation, the tidal volume delivered is determined by the set pressure and lung compliance. Inspiratory time and inspiratory flow, while they can affect the dynamics of airflow, primarily influence how quickly a breath is delivered but do not directly increase the number of ventilatory cycles. Thus, adjusting the respiratory rate is the most effective method for acute management of elevated PaCO2 in this scenario.