THE EFFECT OF CAROTID-ARTERY OCCLUSION ON LINGUAL ARTERIAL BLOOD-PRESSURE IN DOGS

Although temporary occlusion of the carotid arteries is commonly done to reduce blood loss during nasal surgery in the dog, data supporting its use are mostly anecdotal and subjective. Twelve dogs were placed u nder general inhalation anesthesia and mechanically ventilated to main tain normocapnea and an end-tidal halothane concentration equivalent t o 1.3 times the minimum alveolar concentration. Tourniquets were place d around both carotid arteries of each dog. Both lingual arteries were cannulated in each dog and their heart rate and blood pressure were m easured bilaterally. During unilateral carotid artery occlusion, the b lood pressures in the ipsilateral lingual artery were significantly (P < 0.05) lower than the preocclusion control pressures and pressures r ecorded in the contralateral vessel. Bilateral carotid artery occlusio n resulted in a further significant (P < 0.05) fall in all lingual art erial pressures. The recorded heart rates only varied significantly fr om preocclusion control values when they increased during bilateral ca rotid occlusion (P < 0.05). The results of this study confirm that car otid artery occlusion has the potential to reduce intraoperative blood loss during oronasal surgery in the dog.