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Updated: Jan 24, 2026

Brain-Computer Interface-controlled Upper Limb Robotic System for Enhancing Daily Activities in Stroke Patients
Published on: April 18, 2025
[Effect of controlled hypotension on predicting transfusion response and threshold of stroke variability in
Objective:
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 was drawn to determine the accuracy and diagnosis of SVV in predicting volume status in hypertensive and non-hypertensive patients after anti-Trendelenburg posture and pneumoperitoneum. Results: In the patients with controlled hypotension by urapidil, the area under the ROC curve of SVV in the hypertension group was 0.974, the diagnostic threshold was 13.5%, the ROC curve of SVV in the non-hypertension group was 0.832, and the diagnostic threshold was 15.5%. Conclusion: SVV can accurately predict the volume status in the hypertension group and the non-hypertension group after controlled hypotension in the anti-Trendelenburg position and fixed pneumoperitoneal pressure, and the SVV diagnostic threshold in the non-hypertensive group is higher than that in the hypertensive group.
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