What adjustment can be made to improve the oxygenation of a patient receiving mechanical ventilation?

• A. Increase the set tidal volume
• B. Decrease the mandatory rate
• C. Increase the pressure support
• D. Increase the PEEP level

Answer: (D)

The adjustment that can significantly improve the oxygenation of a patient receiving mechanical ventilation is increasing the PEEP (Positive End-Expiratory Pressure) level. PEEP helps to maintain open airways at the end of expiration, which can prevent the collapse of alveoli (atelectasis) and improve ventilation-perfusion matching. By increasing PEEP, you enhance the recruitment of collapsed lung units, thereby increasing the surface area available for gas exchange, which results in improved oxygenation.

Using PEEP effectively also helps to increase functional residual capacity (FRC), allowing for better oxygen exchange during the respiratory cycle. This is particularly beneficial for patients with conditions such as ARDS (Acute Respiratory Distress Syndrome), where lung compliance is reduced, and oxygenation is severely compromised.

Other adjustments, such as increasing tidal volume or adjusting pressure support, primarily focus on enhancing ventilation, which is more about eliminating carbon dioxide than improving oxygenation. While decreasing the mandatory rate can also reduce bronchial hyperinflation, it may not have a direct positive impact on oxygenation compared to an increase in PEEP. Therefore, increasing the PEEP level is a targeted and effective approach to enhance oxygenation for patients on mechanical ventilation.