Cerebral autoregulation during carotid endarterectomy
Research type
Research Study
Full title
Measurement and assessment of impaired static and dynamic cerebral autroregulation in patients undergoing carotid endarterectomy for significant carotid artery stenosis, following stroke or transient ischaemic attack
IRAS ID
130563
Contact name
Ian Loftus
Contact email
Sponsor organisation
St George's Healthcare NHS Trust
Research summary
In a healthy adult patient the brain is able to regulate its own blood flow, and therefore oxygen supply, despite changes in mean arterial pressure (MAP). This provides protection against fluctuations in MAP during stressful events such as surgery, and minute to minute variation due to exercise. The result is prevention of brain injury.\nThere are several studies confirming that cerebral autoregulation is not maintained in stroke patients, especially in the acute phase i.e. within 96 hours. This damage affects the brain’s ability to autoregulate its blood supply, which can cause significant and uncontrollable swings in blood pressure especially at the lower values of MAP. Any drop in blood pressure puts them at risk of cerebral hypoxia as the brain is unable to maintain adequate blood flow. \nThis topic is of particular interest to vascular surgeons who perform an operation called carotid endarterectomy (CEA) on stroke patients in the acute period. CEA has been shown to be of greatest benefit in preventing further acute stroke when performed within 48 hours of the initial insult. In this period, gross fluctuations in mean arterial pressure in these patients are observed during surgery, making it more difficult for the anaesthetist to maintain the controlled physiological state required for adequate cerebral perfusion, and to prevent further damage. Post-operative cognitive decline (POCD) is seen in up to 28% of patients following CEA, and the cause is unknown, although it may be associated with disruption of normal cerebral autoregulation.\nThe aim of this project is to perform an observational study monitoring patients’ limits of autoregulation before, during and after surgery. This work has not been performed before, and it is anticipated that the results will provide surgeons with important information on how to make surgery safer, and improve outcomes for these more complex patients.\n \n
REC name
East of England - Cambridgeshire and Hertfordshire Research Ethics Committee
REC reference
13/EE/0264
Date of REC Opinion
4 Sep 2013
REC opinion
Further Information Favourable Opinion