Conclusions
The PP has been found to enhance the oxygenation index and increase the 10-day survival rate of critically ill COVID-19 patients receiving invasive mechanical ventilation in ICU. The frequency of PP correlates with a more significant improvement in the oxygenation index. However, it is worth noting that the effectiveness of PP may be reduced in patients with lower absolute lymphocyte values, while earlier and longer PP may yield better outcomes. Despite the challenges associated with implementing PP in patients on invasive mechanical ventilation, it is recommended to be performed whenever feasible, provided there are no clear contraindications to invasive mechanical ventilation.