Preoperative Carotid Doppler Ultrasound Parameters for Prediction of Post-Induction Hypotension in Elective Non-Cardiac Surgery

The Value of Preoperative Carotid Doppler Ultrasonography Parameters in Predicting Post-Induction Hypotension in Patients Undergoing Elective Non-Cardiac Surgery

This prospective observational study aims to evaluate the predictive value of preoperative carotid Doppler ultrasound parameters, including carotid velocity-time integral (carotid VTI) and corrected carotid flow time (ccFT), for post-induction hypotension in adult patients undergoing elective non-cardiac surgery under general anesthesia. Hemodynamic instability during anesthesia induction is a common and clinically important problem associated with adverse perioperative outcomes. Carotid Doppler ultrasonography provides a rapid and non-invasive method for assessing hemodynamic status at the bedside. In this study, carotid Doppler measurements will be performed in the preoperative period and their association with post-induction hypotension will be analyzed. The results of this study may help identify patients at risk for hypotension and improve perioperative hemodynamic management.

Study Overview

• Status: Not yet recruiting
• Conditions: Postoperative Morbidity; Post Induction Hypotension

Detailed Description

Post-induction hypotension (PIH) is a common hemodynamic complication during the induction of general anesthesia and is associated with increased risk of perioperative morbidity and mortality. Identifying patients at risk of developing hypotension before anesthesia induction may allow anesthesiologists to implement preventive strategies and optimize perioperative hemodynamic management.

Traditional static hemodynamic parameters are often insufficient to accurately assess intravascular volume status and cardiovascular reserve. Doppler ultrasound-based measurements have emerged as useful non-invasive tools for evaluating cardiovascular dynamics. Carotid Doppler ultrasonography, in particular, allows rapid bedside assessment of hemodynamic parameters such as carotid velocity-time integral (carotid VTI) and corrected carotid flow time (ccFT), which may reflect changes in stroke volume and preload responsiveness.

This prospective observational study aims to evaluate the ability of preoperative carotid Doppler parameters, including carotid VTI and corrected carotid flow time (ccFT), to predict the development of post-induction hypotension in adult patients undergoing elective non-cardiac surgery under general anesthesia. Carotid Doppler measurements will be performed during the preoperative period, and anesthetic induction will be conducted in accordance with the study protocol under standard monitoring conditions. Hemodynamic parameters will be recorded during the induction period, and the occurrence of post-induction hypotension will be documented.

The primary objective of this study is to determine the predictive performance of carotid VTI and corrected carotid flow time for post-induction hypotension. Secondary analyses will explore the relationship between Doppler-derived hemodynamic parameters and perioperative hemodynamic changes. The findings of this study may contribute to improving perioperative risk stratification and guiding individualized hemodynamic management strategies.

• Study Type: Observational
• Enrollment (Estimated): 110

Contacts and Locations

• Study Contact: Name: Engin Kılınç, medical doctor; Phone Number: 00 90 332 223 60 00; Email: enginkilinc96@gmail.com

Study Locations

• Turkey (Türkiye)
  • Konya, Turkey (Türkiye)
    • Necmettin Erbakan University
    • Contact: Engin Kılınç, medical doctor; Phone Number: 00 90 332 223 60 00; Email: enginkilinc96@gmail.com
    • Sub-Investigator: Engin Kılınç, Medical Doctor
    • Principal Investigator: SULE ARICAN, Assoc. Prof.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients aged 18-65 years with American Society of Anesthesiologists (ASA) physical status I-II who are scheduled for elective non-cardiac surgery under general anesthesia will be included in this study.

Description

Inclusion Criteria:

• Adult patients aged 18-65 years

American Society of Anesthesiologists (ASA) physical status I-II

Scheduled for elective non-cardiac surgery under general anesthesia

Planned endotracheal intubation

Ability to provide written informed consent

Exclusion Criteria:

Refusal to participate in the study

Planned emergency surgery

Planned cardiac surgery

Presence of carotid artery stenosis greater than 50%

Moderate to severe valvular heart disease

Presence of atrial fibrillation or significant arrhythmia

Advanced heart failure

Preoperative hypotension or hemodynamic instability

Inability to obtain reliable ultrasonographic measurements

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Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Elective Non-Cardiac Surgery Patients; Patients undergoing elective non-cardiac surgery will be prospectively enrolled. Preoperative carotid Doppler ultrasonography parameters, including carotid velocity time integral (VTI) and corrected carotid flow time (ccFT), will be measured before anesthesia induction. No intervention will be applied as part of the study protocol. Patients will be followed for the occurrence of post-induction hypotension after standardized anesthesia induction.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-induction hypotension	Occurrence of post-induction hypotension after anesthesia induction, defined as either a decrease in mean arterial pressure (MAP) of ≥30% from baseline or a MAP <65 mmHg sustained for at least 1 minute.	From anesthesia induction until 10 minutes after tracheal intubation or until the start of surgery, whichever occurs first.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Predictive performance of carotid Doppler parameters	Diagnostic accuracy of preoperative carotid Doppler parameters (carotid VTI and corrected carotid flow time [ccFT]) for predicting post-induction hypotension, including area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and optimal cut-off values.	From the initiation of anesthetic induction until 10 minutes after tracheal intubation or until surgical incision, whichever occurs first.

Collaborators and Investigators

• Sponsor: Necmettin Erbakan University

Publications and helpful links

General Publications

• Mascha EJ, Yang D, Weiss S, Sessler DI. Intraoperative Mean Arterial Pressure Variability and 30-day Mortality in Patients Having Noncardiac Surgery. Anesthesiology. 2015 Jul;123(1):79-91. doi: 10.1097/ALN.0000000000000686.
• Cheong I, Otero Castro V, Sosa FA, Tort Oribe B, Fruchtenicht MF, Tamagnone FM, Merlo PM. Passive leg raising test using the carotid flow velocity-time integral to predict fluid responsiveness. J Ultrasound. 2024 Mar;27(1):97-104. doi: 10.1007/s40477-023-00824-1. Epub 2023 Sep 5.
• Blanco P
• Cheong I, Otero Castro V, Sosa FA, Tort Oribe B, Merlo PM, Tamagnone FM. Carotid flow as a surrogate of the left ventricular stroke volume. J Clin Monit Comput. 2023 Apr;37(2):661-667. doi: 10.1007/s10877-022-00938-7. Epub 2022 Nov 18.

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): September 1, 2027

Study Registration Dates

• First Submitted: March 17, 2026
• First Submitted That Met QC Criteria: March 17, 2026
• First Posted (Actual): March 23, 2026

Study Record Updates

• Last Update Posted (Actual): March 23, 2026
• Last Update Submitted That Met QC Criteria: March 17, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Doppler Ultrasound; Anesthesia; Velocity Time Integral
• Other Study ID Numbers: 2026/6334

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No