The Effects of Anaesthesia on Cerebral Oxygenation and Cognitive Function in Carotid Endarterectomy
The Effects of Anaesthesia on Cerebral Oxygenation and Cognitive Function in Carotid Endarterectomy
Volatile anesthetics interfere with cerebral blood flow and reperfusion-ischemia injury via
 the mechanism known as a preconditioning. A transient deterioration of local hemodynamics and
 oxygenation during carotid endarterectomy (CEE) might involve both hemispheres of brain and
 affect postoperative cognitive function. The goal of this study was to assess the effects of
 anesthetics on perioperative cerebral oxygenation and cognitive functions.
Background: A transient deterioration of cerebral hemodynamics and oxygenation during CEE
 might involve both hemispheres of the brain and affects postoperative cognition. Despite some
 benefits of regional blocks, the majority of procedures of carotid endarterectomy (CEE) are
 performed under general anaesthesia. Surprisingly, the studies comparing the effects of
 sevoflurane and propofol on postoperative mental state in CEE are scarce and controversial.
 While propofol possesses some anti-inflammatory properties, volatile anesthetics can
 interfere with cerebral blood flow and reperfusion-ischaemia injury via the mechanism of pre-
 and postconditioning. The goal of this study is to assess the effects of the anesthetics on
 the perioperative cerebral oxygenation and cognitive functions in CEE.

 Methods: The study and informed consent are approved by the Ethical Committee of the Northern
 State Medical University. Forty patients (males only) who are to undergo elective CEE will be
 included into a prospective study and randomised to two groups receiving either total
 intravenous anaesthesia (TIVA group, propofol + fentanyl) or the volatile induction and
 maintenance of anaesthesia (VIMA group, n = 20, sevoflurane + fentanyl). All patients were
 operated using temporary carotid bypass. Invasive arterial pressure (AP), gas exchange, and
 cerebral tissue oxygen saturation (SctO2, ForeSight, CAsMed, USA) over frontal region for
 ipsilateral (SctO2IPSI) and contralateral (SctO2CONTR) hemispheres were registered during the
 surgery and up to 20 hrs of the postoperative period. The cognitive changes will be assessed
 at 12 hrs before as well as on Days 1 and 5 after CEE by blinded investigator using Montreal
 Cognitive Assessment score (MoCA).

 Data will be presented as median (25-75th percentiles). Intergroup comparison will be
 provided with Mann-Whitney U-test and correlation analysis with Spearman's coefficient (rho).
 P value below 0.05 was regarded as statistically significant.
Inclusion Criteria:

 -  > 18 years

 -  Male gender

 -  Informed consent

 -  Symptomatic carotid stenosis > 75%

 Exclusion Criteria:

 -  Contralateral carotid occlusion

 -  Known allergy to the one of the compared medications