Clinical Research Directory

Inclusion Criteria: * adult patients requiring MV in ICU Exclusion Criteria: * patients with abdominal or chest trauma, * patients with intra abdominal pathologies, * patients who had received more than 10 units of red blood cells or more than 5 liters of intravenous liquids over the last 24 h, * patients with sepsis or hepatic, or renal dysfunction, * patients in positions other than supine, and * body mass index (BMI) ≥ 30 kg/m2.