The aim of this observational study is to learn the effects of prone position duration on patient outcomes in patients with severe acute respiratory distress syndrome (ARDS) due to Coronavirus Disease - 2019 (COVID-19). The main question it aims to answer is:

Does the length of prone position duration affect gas exchange in patients with severe ARDS and is there a difference between genders in this regard? The differences in gas exchange between those who have been in prone position for 16-24 hours and those who have been in prone position for 24-36 hours as part of severe ARDS treatment will be examined.

Inclusion Criteria:

• >18 years old
• hospitalized for more than 48 hours
• patients diagnosed with COVID-19
• intubated patients
• underwent prone positioning for longer than 16 hours starting from the first session

Exclusion Criteria:

• Pregnant females
• Patients under the age of 18
• Those who did not reach 16 hours duration of prone position for various reasons (unintentional extubation, ventilation problems, hemodynamic instability, cardiac arrest-prearrest)

The study population consisted of Covid-19 ARDS patients hospitalized in the tertiary intensive care unit of a university hospital.

Approval was not obtained from the institute's ethics committee for sharing patient data with an international registry.