Superior Vena Cava Collapsibility Index for Predicting Fluid Responsiveness During High-risk Non-cardiac Surgery

"After induction of general anaesthesia following interventions will be performed.~1. Insertion of a tranesophageal echocardiography probe~2. Measurement of SVC-CI~3. Measurement of LVOT-VTI prior to fluid bolus~4. Fluid bolus (250ml of crystalloid)~5. Measurement of LVOT-VTI after fluid bolus~Several volume trials per patient will be allowed, until safety criteria are met. In such cases further testing will be stopped."

"A transient elevation of positive end-expiratory pressure (PEEP) will be applied, in order to validate SVC-CI in the setting of elevated PEEP.~A PEEP level of 8-10cmH2O will be applied for 1 minute prior to every measurement of SVC-CI. Then the previous PEEP level will be reinstated."