Selective carotid angiography during cross-clamping of the descending thoracic aorta in pigs

Objective. To visualize the intra- and extracranial blood vessels during cross-clamping of the descending thoracic aorta. Experimental design. Experimental animal study. Setting. Animal laboratory, University Hospital. Materials. Seven pigs. Interventions. Cross-clamping of the descending thoracic aorta for 30 minutes. Method. Selective carotid angiography was performed before, during and after cross-clamping. Venous filling time of internal- and external jugular veins, diameter of internal and external jugular veins and internal, external and common carotid arteries and contrast intensity were determined. Results. During cross-clamping the blood flow velocity increased as demonstrated by decreased venous filling time and decreased contrast intensity. In addition, the diameter of the external jugular Vein increased and the diameter of the internal carotid artery decreased during cross-clamping. No arteriovenous anastomoses could be detected during the experiment. Conclusions. Our results indicate increased intra- and extracranial blood flow during cross-clamping of the descending thoracic aorta in pigs.