Carotid artery stump pressure: its variability when measured serially

Area of Science:

• Neurosurgery
• Vascular Surgery
• Anesthesiology

Background:

• Carotid endarterectomy is a common procedure to prevent stroke.
• Carotid artery stump pressure (CSP) is used to guide the decision for intraoperative bypass shunt placement.
• Variability in CSP may influence the reliability of this decision-making criterion.

Purpose of the Study:

• To assess the serial variability of carotid artery stump pressure (CSP) during carotid endarterectomy.
• To determine the proportion of patients with significant CSP fluctuations that could alter shunt management.
• To identify factors associated with CSP variability.

Main Methods:

• Serial measurement of CSP in 174 patients undergoing 189 carotid endarterectomies under eucarbic general anesthesia.
• Analysis of CSP variations relative to a threshold of 50 torr.
• Correlation of CSP variability with patient demographics, preoperative status, and imaging findings.

Main Results:

• Significant CSP variation occurred in 19.5% of patients (34/174), potentially affecting shunt decisions.
• In patients with initial CSP < 50 torr, 34% (26/76) later exceeded 50 torr.
• In patients with initial CSP ≥ 50 torr, 7% (8/113) later dropped below 50 torr.
• CSP variability was not linked to age, sex, intracranial disease, or contralateral stenosis.
• Preoperative status significantly influenced CSP: asymptomatic (89%), TIA (62%), prior stroke (54%).

Conclusions:

• Carotid artery stump pressure exhibits significant variability in a substantial portion of patients undergoing carotid endarterectomy.
• This variability may contribute to conflicting findings regarding the necessity of bypass shunts in this surgical population.
• Preoperative patient status is a key factor associated with CSP levels.