Carotid Artery Corrected Flow Time Measured by Ultrasonography as a Predictor of Hypotension After Induction of General Anesthesia

General Anesthesia Induction for Elective Surgery Clinical Trial

Official title:

Carotid Artery Corrected Flow Time Measured by Ultrasonography as a Predictor of Hypotension After Induction of General Anesthesia

Clinical Trial Details — Status: Withdrawn

Administrative data

• NCT number: NCT02891772
• Other study ID #: 4-2016-0606
• Status: Withdrawn
• Start date: August 2016
• Est. completion date: August 2017

Study information

• Verified date: January 2019
• Source: Yonsei University
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Hypotension often happens immediately after anesthetic induction. Particularly in 5-10 minutes after anesthetic induction it is reported to happen more frequently. Patients may have preexisting hypovolemia resulting from dehydration and impaired compensatory responses, which increase the risk. However, it is still challenging to assess intravascular volume status in spontaneously breathing patients before anesthetic induction. Recently, the measurement of corrected flow time in carotid artery was introduced as quite useful, simple and noninvasive for the evaluation of circulating blood volume. The aim of this study is to evaluate whether corrected carotid artery flow time as determined by ultrasonography in spontaneously breathing patients before general anesthesia can predict hypotension after induction.

Recruitment information / eligibility

• Status: Withdrawn
• Enrollment: 0
• Est. completion date: August 2017
• Est. primary completion date: August 2017
• Accepts healthy volunteers: No
• Gender: All
• Age group: 19 Years to 80 Years

Eligibility

Inclusion Criteria:

• adult patients (19-80 years of age) who were scheduled to undergo elective surgery under general anesthesia

Exclusion Criteria:

• mean blood pressure < 70 mmHg before induction of general anesthesia

• Patients who have currently taken angiotensin-converting enzyme inhibitor

• Patients who have currently taken angiotensin receptor blocker

• the presence of carotid artery stenosis > 50%

• cardiac rhythm other than sinus

• unstable angina

• a left ventricular ejection fraction of < 40%

• severe vascular disease

• implanted pacemaker/cardioverter

• autonomic nervous system disorders

• anticipated difficult airway

• pregnancy

Related Conditions & MeSH terms

• General Anesthesia Induction for Elective Surgery
• Hypotension

Intervention

Procedure:
• ultrasonographic measurement of corrected flow time(FTc) in carotid artery
Corrected carotid artery flow time is measured using 10-5 MHz linear probe on a portable ultrasound machine. On the two-dimensional image, the optimal image of the long-axis view is obtained at the left common carotid artery. The sample volume is placed on the center of the lumen, 2 cm proximal to the bulb, and a pulsed wave Doppler examination was performed. Then, cardiac cycle time and carotid flow time is measured. Carotid flow time is measured between the upstroke of the flow tracing and the dicrotic notch, and it is corrected for pulse rate by dividing flow time by the square root of the cardiac cycle time to calculate corrected carotid artery flow time (flow time/vcycle time). The blood pressure was taken before anesthetic induction and every two minutes after anesthetic induction till ten minutes after endotracheal intubation.

Locations

Country	Name	City	State
Korea, Republic of	Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institue, Yonsei Universiy College of Medicine	Seoul

Sponsors (1)

Lead Sponsor	Collaborator
Yonsei University

Country where clinical trial is conducted

Korea, Republic of, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	corrected flow time (FTc) in carotid artery	the area under the receiver operating characteristics curve of corrected flow time in carotid artery measured by ultrasonography to predict hypotension after anesthetic induction	10 minutes before induction of general anesthesia.