Carotid Ultrasound for Post-Spinal Anesthesia Hypotension in Elderly Hip Surgery

This study aims to evaluate the predictability of preoperative carotid artery-corrected flow time (CFTc) for hypotension after spinal anesthesia in patients undergoing geriatric hip replacement surgery. Primary outcomes: • The predictive performance of preoperative CFTc for post-spinal hypotension . Secondary outcomes: * Cut-off value, sensitivity, specificity, positive predictive value and negative predictive value of CFTc in prediction of hypotension. * Cut-off value, sensitivity, specificity, positive predictive value and negative predictive value of IVC collapsibility. * Cut-off value, sensitivity, specificity, positive predictive value and negative predictive value of echocardiography (ECHO) (LVOT-VTI). * Comparison of predictive accuracy of CFTc, IVC, and ECHO for post-spinal hypotension. * Monitoring of systolic blood pressure (SBP), mean arterial pressure (MAP), and heart rate (HR) (first 10 min every 2 minutes, then at 15 min and at 20 min).