title: External carotid compression: a novel technique to improve cerebral perfusion during selective antegrade cerebral perfusion for aortic arch surgery.
abstract: OBJECTIVE
  Selective antegrade cerebral perfusion (SACP) involving cannulation of either the axillary or innominate artery is a commonly used technique for maintaining cerebral blood flow (CBF) during the use of hypothermic cardiac arrest (HCA) for operations on the aortic arch. Nevertheless, asymmetrical CBF with hypoperfusion of the left cerebral hemisphere is a common occurrence during SACP. The purpose of this report is to describe an adjunctive maneuver to improve left hemispheric CBF during SACP by applying extrinsic compression to the left carotid artery.
  
  
  METHODS
  A 77-yr-old male patient with a history of aortic valve replacement presented for emergent surgical repair of an acute type A aortic dissection of a previously known ascending aortic aneurysm. His intraoperative course included cannulation of the right axillary artery, which was used as the aortic inflow during cardiopulmonary bypass and also allowed for subsequent SACP during HCA. After the onset of HCA, the innominate artery was clamped at its origin to allow for SACP. Shortly thereafter, however, the left-sided cerebral oxygen saturation (SrO2) began to decrease. Augmenting the PaO2, PaCO2 and both SACP pressure and flow failed to increase left hemispheric SrO2. Following the use of ultrasound guidance to confirm the absence of atherosclerotic disease in the carotid artery, external pressure was applied partially compressing the artery. With the carotid compression, the left cerebral saturation abruptly increased, suggesting pressurization of the left cerebral hemispheric circulation and augmentation of CBF.
  
  
  CONCLUSIONS
  Direct ultrasound visualization and cautious partial compression of the left carotid artery may address asymmetrical CBF that occurs with SACP during HCA for aortic arch surgery. This strategy may lead to improved symmetry of CBF and corresponding cerebral oximetry measurements during aortic arch surgery.
authors.affiliation: Departments of Anesthesia & Perioperative Medicine and Surgery, University of Manitoba, CR3008 - 369 Tache Avenue, Winnipeg, MB, R2H 2A6, Canada. hgrocott@sbgh.mb.ca.
authors.forename: Hilary P
authors.initials: HP
authors.lastname: Grocott
authors.affiliation: Department of Anesthesia and Perioperative Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Emma
authors.initials: E
authors.lastname: Avery
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, AB, Canada.
authors.forename: Mike
authors.initials: M
authors.lastname: Moon
mesh_terms: D000368:Aged; D001011:Aorta / Q000601:surgery; D001015:Aortic Arch Syndromes / Q000000981:diagnostic imaging / Q000601:surgery*; D001019:Aortic Rupture / Q000601:surgery; D002245:Carbon Dioxide / Q000097:blood; D006348:Cardiac Surgical Procedures / Q000379:methods*; D002315:Cardiopulmonary Bypass; D002342:Carotid Artery, External / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation; D050792:Circulatory Arrest, Deep Hypothermia Induced; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D010092:Oximetry; D010100:Oxygen / Q000097:blood
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen