Evaluation of the Correlation Between Carotid Stump Pressure and Interhemispheric rSO₂ Asymmetry in Awake Carotid Endarterectomy: A Prospective Cohort Study
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- Difference in Carotid Stump Pressure Between Interhemispheric rSO₂ Symmetry and Asymmetry Groups
研究概览
简要总结
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.
详细描述
Carotid artery stenosis accounts for approximately 15-30% of ischemic strokes, highlighting the importance of carotid endarterectomy (CEA) as a preventive surgical strategy. One of the most critical intraoperative concerns during CEA is cerebral hypoperfusion at the time of carotid cross-clamping, when antegrade ipsilateral blood flow is interrupted. Monitoring cerebral oxygenation and collateral circulation during this period is essential to reduce the risk of ischemic complications. Traditionally, carotid stump pressure (SP) measurement has been used as a surrogate of collateral flow, whereas near-infrared spectroscopy (NIRS) provides a continuous, non-invasive estimate of regional cerebral oxygen saturation (rSO₂). While both tools are widely used, each has limitations, and there is no universal consensus on their predictive thresholds. Recent interest has shifted toward analyzing interhemispheric asymmetry in rSO₂ as a potentially physiological marker of cerebral perfusion adequacy in other clinical conditions.
This prospective, single-center observational cohort study will evaluate the association between carotid stump pressure and interhemispheric rSO₂ asymmetry in patients undergoing awake CEA under regional anesthesia. All patients will undergo awake CEA under regional anesthesia (superficial cervical plexus block) with bilateral NIRS monitoring and intraoperative stump pressure measurement. Data will be collected at baseline (before cross-clamping) and 3 minutes after carotid cross-clamp application. Patients will be stratified into two groups based on interhemispheric ΔrSO₂ asymmetry (>10% vs. ≤10%).
The primary objective is to determine whether stump pressure values differ significantly between patients with interhemispheric rSO₂ asymmetry greater than 10% (asymmetry group) compared with those with asymmetry of 10% or less (symmetry group).
Secondary objectives include:
Interhemispheric asymmetry difference;
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •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
排除标准
- •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
研究组 & 干预措施
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.
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.
结局指标
主要结局
Difference in Carotid Stump Pressure Between Interhemispheric rSO₂ Symmetry and Asymmetry Groups
时间窗: 3 minutes after carotid cross-clamping (intraoperative period)
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%).
次要结局
- 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))
- Independent Predictive Value of Carotid Stump Pressure for rSO₂ Asymmetry in Multivariable Logistic Regression(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))
- Comparison of Intraoperative Arterial Pressures Between Asymmetry and Symmetry Groups(Intraoperative period (from anesthesia start to end of surgery))
- Comparison of Intraoperative Heart Rate Between Asymmetry and Symmetry Groups(Intraoperative period (from anesthesia start to end of surgery))
- Comparison of Intraoperative Arterial Oxygen Pressure (PaO₂) Between Asymmetry and Symmetry Groups(Intraoperative period (from anesthesia start to end of surgery))
- Comparison of Intraoperative Peripheral Oxygen Saturation (SpO₂) Between Asymmetry and Symmetry Groups(Intraoperative period (from anesthesia start to end of surgery))
- Comparison of Cross-Clamp Duration, Total Surgical Time, and Total Anesthesia Time Between Asymmetry and Symmetry Groups(Intraoperative period (from anesthesia start to end of surgery))
- Comparison of Intraoperative Shunt Requirement Between Asymmetry and Symmetry Groups(Intraoperative period (from anesthesia start to end of surgery))
- Incidence of Postoperative Complications Within 30 Days(From date of surgery through postoperative day 30)
研究者
Ahmet Salih Tüzen, MD
Principal Investigator, Department of Anesthesiology and Reanimation
Izmir Katip Celebi University