HypotensionNCT06905535
Corrected Carotid Flow Time for Predicting Spinal Anesthesia-induced Hypotension
An observational study of Hypotension, run by Selcuk University.
Trial summary
Spinal anaesthesia is a standard technique frequently preferred for caesarean section. However, spinal anaesthesia-induced hypotension remains a critical problem causing undesirable maternal symptoms such as nausea, vomiting and dyspnoea and adverse consequences for umbilical acidosis and the fetus. Read more about this study
- Who is it for?
- Ages 18 to 40 years, women only
- Conditions the study is for
- Hypotension
- How many people
- 50 participants
- Where
- No sites listed yet
- Study dates
- 1 Apr 2025to 30 Jun 2025
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 40 years
- Women only
- No healthy volunteers
- Adult
Study population: Patients undergoing cesarean section in Selcuk University Faculty of Medicine Hospital Gynecology Operating Room
Who may be able to join
- Full-term pregnancy
- physical status II of American Society of Anesthesiologists
Who cannot join
- emergency cesarean section,
- cesarean under general anesthesia
- gestational Diabetes Mellitus
- gestational Hypertension
- preeclampsia,
- cardiovascular disease
- cerebrovascular disease
- chronic kidney disease disease
About this study
Official title: The Effect of Carotid Corrected Blood Flow Time Measured in the Left Lateral Tilt Position on the Prediction of Spinal Anaesthesia-induced Hypotension in Caesarean Section
Spinal anaesthesia is a standard technique frequently preferred for caesarean section. However, spinal anaesthesia-induced hypotension remains a critical problem causing undesirable maternal symptoms such as nausea, vomiting and dyspnoea and adverse consequences for umbilical acidosis and the fetus. One of the reasons aggravating hypotension is aortocaval compression of the growing uterus and consequent decrease in preload and stroke volume . Therefore, left lateral tilt position is recommended in pregnant women after the 20th gestational week to prevent supine hypotension. This position decreases uterine compression on the vena cava and increases venous return to the heart and thus stroke volume. Recently, carotid artery Doppler has been used to assess stroke volume. Many studies have shown that carotid corrected flow time increases significantly after expansion of intravascular volume in hypovolaemic patients . In one study, it was reported that the change in carotid artery blood flow time induced by passive leg raising predicts fluid sensitivity in critically ill patients. It has been reported that changes in carotid artery blood flow time against hemodynamic interventions (such as Trendelenburg position) reflect maternal hypovolemic status and distinguish hypovolemic patients with a higher risk of spinal anesthesia-related hypotension. The investigators also think that the left lateral tilt position may increase the corrected carotid flow time by affecting hemodynamics and may differentiate the patient with a high risk of hypotension.
Read the detailed description
Patients undergoing elective cesarean section under spinal anesthesia will be included in the study. Carotid corrected flow time will be measured by Doppler ultrasonography in the supine and left lateral tilt (15°) positions before spinal anesthesia. Flow time will be measured using pulse Doppler waveforms in the long axis of the right common carotid artery. The measured flow time will be calculated as "corrected flow time" using the following Wodey formula; Carotid corrected flow time = measured flow time + [1.29 (Heart rate - 60)].
After standard monitoring (Electrocardiography, peripheral oxygen saturation, noninvasive blood pressure measurement), routine spinal anesthesia will be performed without any study-specific changes. The noninvasive blood pressure value measured before spinal anesthesia will be taken as the baseline value and a decrease of 20% or more in this value or a decrease in systolic blood pressure below 100 mmHg will be considered as "spinal anesthesia induced hypotension". Patients will be divided into those who develop spinal anesthesia-induced hypotension and those who do not develop spinal anesthesia-induced hypotension after spinal anesthesia and carotid corrected flow times will be compared between both groups.
- Conditions
- Hypotension
- Keywords
- spinal anesthesia induced hypotension, carotid flow time
- Medical subject headings
- Hypotension
What is being measured
The primary outcome is the main question the study is designed to answer.
predictive value of the carotid flow time alteration
rate of prediction
Measured: 10-15 minute
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Apr 2025
- Study start1 Apr 2025 (estimated)
- Primary completion30 May 2025 (estimated)
- Study completion30 Jun 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HypotensionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Selcuk University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, EMİNE ASLANLAR, Selcuk University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06905535
- Sponsor's protocol ID
- carotis flow
- Status last verified
- Apr 2025
- First submitted
- 13 Dec 2024
- Last updated
- 9 Apr 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 9 Apr 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Carotid Corrected Blood Flow Time Measured in the Left Lateral Tilt Position on the Prediction of Spinal Anaesthesia-induced Hypotension in Caesarean Section
- ClinicalTrials.gov ID
- NCT06905535
- Acronym / sponsor ID
- carotis flow
- Conditions
- Hypotension
- Keywords
- spinal anesthesia induced hypotension, carotid flow time
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Selcuk UniversityUniversity, hospital or other
- Study start
- 1 Apr 2025 (estimated)
- Primary completion
- 30 May 2025 (estimated)
- Study completion
- 30 Jun 2025 (estimated)
- First posted
- 1 Apr 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Spinal anaesthesia is a standard technique frequently preferred for caesarean section. However, spinal anaesthesia-induced hypotension remains a critical problem causing undesirable maternal symptoms such as nausea, vomiting and dyspnoea and adverse consequences for umbilical acidosis and the fetus. One of the reasons aggravating hypotension is aortocaval compression of the growing uterus and consequent decrease in preload and stroke volume . Therefore, left lateral tilt position is recommended in pregnant women after the 20th gestational week to prevent supine hypotension. This position decreases uterine compression on the vena cava and increases venous return to the heart and thus stroke volume. Recently, carotid artery Doppler has been used to assess stroke volume. Many studies have shown that carotid corrected flow time increases significantly after expansion of intravascular volume in hypovolaemic patients . In one study, it was reported that the change in carotid artery blood flow time induced by passive leg raising predicts fluid sensitivity in critically ill patients. It has been reported that changes in carotid artery blood flow time against hemodynamic interventions (such as Trendelenburg position) reflect maternal hypovolemic status and distinguish hypovolemic patients with a higher risk of spinal anesthesia-related hypotension. The investigators also think that the left lateral tilt position may increase the corrected carotid flow time by affecting hemodynamics and may differentiate the patient with a high risk of hypotension.
Detailed description
Patients undergoing elective cesarean section under spinal anesthesia will be included in the study. Carotid corrected flow time will be measured by Doppler ultrasonography in the supine and left lateral tilt (15°) positions before spinal anesthesia. Flow time will be measured using pulse Doppler waveforms in the long axis of the right common carotid artery. The measured flow time will be calculated as "corrected flow time" using the following Wodey formula; Carotid corrected flow time = measured flow time + [1.29 (Heart rate - 60)].
After standard monitoring (Electrocardiography, peripheral oxygen saturation, noninvasive blood pressure measurement), routine spinal anesthesia will be performed without any study-specific changes. The noninvasive blood pressure value measured before spinal anesthesia will be taken as the baseline value and a decrease of 20% or more in this value or a decrease in systolic blood pressure below 100 mmHg will be considered as "spinal anesthesia induced hypotension". Patients will be divided into those who develop spinal anesthesia-induced hypotension and those who do not develop spinal anesthesia-induced hypotension after spinal anesthesia and carotid corrected flow times will be compared between both groups.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 to 40 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
- Study population
- Patients undergoing cesarean section in Selcuk University Faculty of Medicine Hospital Gynecology Operating Room
Key inclusion criteria (2 listed)
- Full-term pregnancy
- physical status II of American Society of Anesthesiologists
Key exclusion criteria (8 listed)
- emergency cesarean section,
- cesarean under general anesthesia
- gestational Diabetes Mellitus
- gestational Hypertension
- preeclampsia,
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
predictive value of the carotid flow time alteration
Time frame: 10-15 minute
rate of prediction
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Apr 2025.
Related trials for Hypotension
Not yet recruiting
Applying HPI in Oral Cancer Surgery
the Severity and Duration of Intraoperative Hypotension
RecruitingPhase 4
Effect of Remimazolam Versus Propofol Total Intravenous Anesthesia on Intraoperative Hemodynamic Stability in Patients Undergoing Thoracic or Abdominal Endovascular Aortic Repair
Aortic Aneurysm, Thoracoabdominal, Aortic Aneurysm, Abdominal
Not yet recruitingPhase 4
OB VEGA-Phenylephrine vs Norepinephrine Outcomes
Hypotension During Surgery, Cesarean Birth
Recruiting
Community Health Worker Support to Lower Blood Pressure After a Pregnancy With High Blood Pressure
Pregnancy-Associated Hypertension, Gestational Hypertension
RecruitingObservational study
The Role of Preoperative Internal Jugular Vein Collapsibility and Perfusion Index in Predicting Hypotension After Spinal Anesthesia in Elective Cesarean Sections: A Prospective Observational Study
Postspinal Hypotension, Cesarean Birth
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
An observational study of Hypotension, run by Selcuk University.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 9 Apr 2025. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
predictive value of the carotid flow time alteration (time frame: 10-15 minute). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Apr 2025.