Send to

Choose Destination
Am J Physiol Regul Integr Comp Physiol. 2014 May 15;306(10):R747-51. doi: 10.1152/ajpregu.00535.2013. Epub 2014 Mar 5.

Regional redistribution of blood flow in the external and internal carotid arteries during acute hypotension.

Author information

Department of Biomedical Engineering, Toyo University, Kawagoe-Shi, Saitama, Japan;
Université de Caen Basse-Normandie and Institut National de la Santé et de la Recherche Médicale, U-1075, F-14032, Caen, France; and.
Department of Biomedical Engineering, Toyo University, Kawagoe-Shi, Saitama, Japan;
Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, United Kingdom.


The present study examined to what extent an acute bout of hypotension influences blood flow in the external carotid artery (ECA) and the corresponding implications for blood flow regulation in the internal carotid artery (ICA). Nine healthy male participants were subjected to an abrupt decrease in arterial pressure via the thigh-cuff inflation-deflation technique. Duplex ultrasound was employed to measure beat-to-beat ECA and ICA blood flow. Compared with the baseline normotensive control, acute hypotension resulted in a heterogeneous blood flow response. ICA blood flow initially decreased following cuff release and then returned quickly to baseline levels. In contrast, the reduction in ECA blood flow persisted for 30 s following cuff release. Thus, the contribution of common carotid artery blood flow to the ECA circulation decreased during acute hypotension (-10 ± 4%, P < 0.001). This finding suggests that a preserved reduction in ECA blood flow, as well as dynamic cerebral autoregulation likely prevent a further decrease in intracranial blood flow during acute hypotension. The peripheral vasculature of the ECA may, thus, be considered an important vascular bed for intracranial cerebral blood flow regulation.


arterial baroreflex; arterial blood pressure; common carotid artery; humans; skin blood flow

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center