Carotid Artery Corrected Flow Time and Respiratory Variation of Blood Flow Peak Velocity for Prediction of Hypotension after Induction of General Anesthesia in Elderly Patients Undergoing Elective Open Abdominal Surgery: A Prospective Observational Study.

Elderly patients undergoing major abdominal surgeries such as laparotomy are at a higher risk of developing hypotension following induction of general anesthesia due to age-related cardiovascular changes and altered autonomic regulation. Early prediction of post-induction hypotension allows timely preventive measures, such as optimized fluid therapy and vasopressor support.

This prospective observational study aims to evaluate whether noninvasive Doppler-derived parameter such as carotid artery corrected flow time and respiratory variation of blood flow peak velocity can predict the occurrence of hypotension after induction of general anesthesia in elderly patients undergoing elective laparotomy.

Pre-induction CFT and variation in  Vpeak will be measured using carotid Doppler ultrasound, and hemodynamic parameters will be recorded immediately after induction and for 5 minutes thereafter. The correlation of these ultrasound indices with hypotension will be analyzed, along with their sensitivity, specificity, and accuracy compared to conventional predictors such as age, comorbidities, and baseline blood pressure.

Findings from this study may help identify simple, noninvasive, bedside tools to anticipate and prevent anesthesia-induced hypotension in high-risk elderly patients.