title: [Indirect measurement of residual internal carotid pressure by photoplethysmography during the carotid occlusion test].
abstract: A non invasive technique for measuring the systolic arterial pressure in the internal carotid artery during common carotid artery occlusion test is described. Its objective is to predict the efficiency of the collateral circulation through the circle of Willis during surgical carotid artery clamping. Photoplethysmographic curves were recorded on two facial areas supplied by the external carotid artery (earlobe and forehead above the center of one eyebrow). The residual carotid artery pressure during carotid clamping was estimated by considering the ratio of determined by the systolic brachial arterial pressure over the amplitude of the best photoplethysmographic curve obtained, multiplied by the amplitude of the photoplethysmographic curves recorded during the percutaneous compression of the common carotid artery. This method was verified on 15 patients (women: 6, men: 9) with carotid lesions, during carotid endarterectomy. The invasive measurement of the systolic pressure in the internal carotid during carotid clamping was compared with the calculated value. This comparison showed a highly significant correlation between the two values (p less than 0.001). Thus, a simple and non-invasive method of estimating the internal carotid systolic pressure during carotid clamping is described, so that the efficiency of the collateral circulation during this period may be assessed before surgery.
mesh_terms: D001795:Blood Pressure Determination / Q000379:methods*; D002339:Carotid Arteries; D005260:Female; D006801:Humans; D008027:Light; D008297:Male; D010991:Plethysmography / Q000379:methods*; D013599:Systole
vernacular_title: Mesure indirecte de la pression résiduelle de la carotide interne par photopléthysmographie lors du test d'occlusion carotidienne.