What action should a RT take for a patient with mechanical ventilation settings of PEEP 15 and low PaO2 levels?

In the context of a patient on mechanical ventilation with high PEEP settings (in this case, 15 cm H2O) and low arterial oxygen levels (PaO2), it is important to consider the impact of PEEP on oxygenation. While PEEP is often used to improve oxygenation by recruiting collapsed alveoli and increasing functional residual capacity, excessively high PEEP can also result in reduced cardiac output and potential barotrauma, which may worsen oxygenation rather than improve it.

In this scenario, reducing the PEEP setting may be the appropriate intervention if the high PEEP is causing hemodynamic instability or not contributing positively to the patient's oxygenation. A lower PEEP can help reduce the intrathoracic pressure, potentially improving venous return and myocardial function, which may ultimately enhance oxygen delivery and improve the patient's PaO2 levels.

Making adjustments to tidal volume, switching to pressure control, or increasing FiO2 might be considered, but these actions do not directly address the potential negative effects of high PEEP in this particular situation. Reducing the PEEP aims to balance the need for oxygenation with the physiological effects of mechanical ventilation, making it a suitable choice.