How can the FIO2 be adjusted effectively during mechanical ventilation?

• A. By changing the fraction of inspired oxygen delivered to the patient
• B. By altering the respiratory rate
• C. By increasing the tidal volume
• D. By adjusting the pressure support

Answer: (A)

To adjust the FIO2 (fraction of inspired oxygen) effectively during mechanical ventilation, the key method involves directly changing the fraction of inspired oxygen delivered to the patient. FIO2 is a measure of how much oxygen is present in the air a patient is breathing. In mechanical ventilation, this is typically controlled by a setting on the ventilator that allows the clinician to specify the exact percentage of oxygen the patient receives.

Modifying the FIO2 is important for optimizing oxygen delivery to meet the respiratory needs of the patient, especially in cases of hypoxemia or when the oxygen levels in the blood need to be carefully managed. This direct adjustment is immediate and clearly influences the oxygen levels provided to the patient, ensuring timely interventions based on the patient's oxygenation status.

While altering the respiratory rate, increasing tidal volume, or adjusting pressure support can impact a patient’s overall breathing mechanics and ventilation-perfusion matching, these actions do not directly change the concentration of oxygen the patient is inspired. Therefore, to appropriately regulate the FIO2 during mechanical ventilation, it is essential to focus on adjusting the fraction of inspired oxygen delivered.