Evaluation of volume responsiveness by pulse pressure variability and inferior vena cava dispensability index at different tidal volumes by mechanical ventilation

This study investigated the effects of tidal volume (TV) on the diagnostic value of pulse pressure variation (PPV) and the inferior vena cava dispensability index (IVC-DI) for volume responsiveness during mechanical ventilation. In patients undergoing elective surgery with mechanical ventilation, different TVs of 6, 9, and 12 mL/kg were given for two min. The left ventricular outflow tract velocity-time integral (VTI) was measured by transthoracic echocardiography. The IVC-DI was measured at sub-xyphoid transabdominal long axis. The PPV was measured via the radial artery and served as baseline...