Effect of controlled hypotension on predicting transfusion response and threshold of stroke variability in hypertensive patients undergoing robotic hepatobiliary surgery

To investigate the effect of controlled hypotension by urapidil on the predictive accuracy and diagnostic threshold of stroke volume variation (SVV) in hypertensive and non-hypertensive patients undergoing robotic hepatobiliary surgery. Methods: Eighty patients undergoing robotic hepatobiliary surgery under general anesthesia were divided into a hypertension group (n=25) and a non-hypertension group (n=38) according to whether or not essential hypertension was present (excluding some cases that didn't meet requirements). The pump speed was at 6.0-7.0 µg/(kg﹒min), and the range of hypotension was between 10%≤Δ systolic blood pressure (SAP)≤20%. Volume loading test was performed after artificial pneumoperitoneum was established in reverse-Trendelenburg position. Hemodynamic indexes including heart rate (HR), SAP, cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke volume index (SVI) and SVV were recorded before and after infusion. Then the receiver operating characteristic (ROC) curves of SVV w