Correlation Between Carotid Stump Pressure and Interhemispheric rSO₂ Asymmetry During Awake Carotid Endarterectomy

NCT07150260 | Recruiting

• 1 other identifier: 2025-0442
• Study Type: observational
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to better understand how well the brain is perfused (supplied with blood and oxygen) during a specific type of surgery called carotid endarterectomy (CEA), which is performed to prevent strokes in people with stenosis of carotid arteries. During this surgery, the surgeon temporarily clamps the carotid artery to remove a blockage, which can reduce blood flow to the brain. Monitoring brain oxygen levels during this time is important to prevent brain injury. Two common monitoring methods are: Stump pressure (SP) - a pressure measurement taken from the carotid artery during surgery. Near-infrared spectroscopy (NIRS) - a non-invasive technique that tracks brain oxygen levels in real time. This study focuses on the relationship between carotid stump pressure and differences in brain oxygenation between the two sides of the brain (interhemispheric asymmetry), as measured by NIRS. The study will include patients undergoing awake CEA (under regional anesthesia) at a single center university hospital. Oxygen levels in both hemispheres of the brain will be monitored before and after the carotid artery is clamped after 3 minutes. Stump pressure will also be measured. The researchers will examine whether low stump pressure is linked to greater differences in brain oxygen levels between the two sides. The primary goal is to determine whether a large difference in brain oxygenation between the two hemispheres (greater than 10%) is associated with low carotid stump pressure. Secondary goals include identifying a stump pressure threshold that predicts significant asymmetry and analyzing the influence of patient and surgical factors. The findings may help improve how surgeons and anesthesiologists monitor and protect the brain during CEA, particularly in patients who are awake and can be observed for neurological changes.

Conditions

Carotid Endarterectomy (CEA) Surgical Patients; Cerebral Hypoperfusion; Carotid Artery Stenosis Symptomatic

Keywords

Carotid stump pressure; Near-infrared spectroscopy; rSO₂ asymmetry; Cerebral oxygenation; Awake carotid endarterectomy; Regional anesthesia

Outcome Measures

Primary Outcomes (1)

• Difference in Carotid Stump Pressure Between Interhemispheric rSO₂ Symmetry and Asymmetry Groups

  The primary outcome is the comparison of intraoperative carotid stump pressure (SP) between patients with significant interhemispheric cerebral oxygenation asymmetry (\>10% ΔrSO₂ difference) and those with nonsignificant asymmetry (≤10%).

  3 minutes after carotid cross-clamping (intraoperative period)

Secondary Outcomes (12)

• Interhemispheric asymmetry difference

  3 minutes after carotid cross-clamping (intraoperative period)

• Correlation Between Carotid Stump Pressure and Interhemispheric ΔrSO₂ Difference

  3 minutes after carotid cross-clamping (intraoperative period)

• Correlation Between Carotid Stump Pressure and Ipsilateral ΔrSO₂

  3 minutes after carotid cross-clamping (intraoperative period)

• Carotid Stump Pressure Threshold Predictive of rSO₂ Asymmetry Using ROC Curve Analysis

  3 minutes after carotid cross-clamping (intraoperative period)

• Independent Predictive Value of Carotid Stump Pressure for rSO₂ Asymmetry in Multivariable Logistic Regression

  3 minutes after carotid cross-clamping (intraoperative period)

Study Arms (2)

Cerebral Asymmetry Group (>10% rSO₂ Difference)

This group includes patients who exhibit a significant interhemispheric cerebral oxygenation asymmetry during awake carotid endarterectomy, defined as an absolute difference in ΔrSO₂ greater than 10% between the ipsilateral (surgical) and contralateral hemispheres.

Cerebral Symmetry Group (≤10% rSO₂ Difference)

This group includes patients who exhibit a nonsignificant interhemispheric cerebral oxygenation asymmetry during awake carotid endarterectomy, defined as an absolute difference in ΔrSO₂ lesser than 10% between the ipsilateral (surgical) and contralateral hemispheres.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adult patients (≥18 years) undergoing elective carotid endarterectomy (CEA) under regional anesthesia at a single tertiary academic hospital. All participants must be able to tolerate awake surgery with regional anesthesia (superficial cervical plexus block) and undergo bilateral near-infrared spectroscopy (NIRS) monitoring and carotid stump pressure measurement during the procedure.

You may qualify if:

• Adults aged 18 years or older
• Scheduled for elective carotid endarterectomy (CEA)
• Able to tolerate surgery under regional anesthesia (superficial cervical plexus block)
• Availability of bilateral regional cerebral oxygen saturation (rSO₂) measurements by near-infrared spectroscopy (NIRS)
• Successful intraoperative carotid stump pressure (SP) measurement after cross-clamping
• Provided written informed consent

You may not qualify if:

• Incomplete NIRS or SP recordings
• Conversion from regional to general anesthesia
• Intraoperative technical complications preventing monitoring
• History of prior ipsilateral carotid endarterectomy or carotid artery stenting
• Recent major stroke with permanent neurological deficit
• Recent myocardial infarction within the past 3 months
• History of traumatic brain injury within the past 6 months

Sponsors & Collaborators

• Izmir Katip Celebi University: lead

Study Sites (1)

Izmir Katip Celebi University Atatürk Training and Research Hospital

Izmir, Turkey (Türkiye)

RECRUITING

Study Officials

• Ahmet Salih Tüzen, M.D:

  Izmir Katip Celebi University Atatürk Training and Research Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Ahmet Salih Tüzen, M.D.

CONTACT

+90 535 391 55 77; astuzen@icloud.com

Murat Aksun, M.D.

CONTACT

murataksun@yahoo.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 30 Days
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator, Department of Anesthesiology and Reanimation

Study Record Dates

• First Submitted: August 24, 2025
• First Posted: September 2, 2025
• Study Start: September 1, 2025
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): October 1, 2026
• Last Updated: January 7, 2026

Record last verified: 2026-01

Locations

TU (1)