Quincke’s pulse [Heinrich I. Quincke] , an abnormal alternate blanching and reddening of the skin or nails that may be observed in several ways, such as by pressing the front edge of the fingernail and watching the blood in the nailbed recede and return. This pulsation is characteristic of aortic insufficiency and other abnormal conditions but may also occur in otherwise normal individuals. Formerly it was thought to be caused by pulsation of the capillaries; it is now known to be caused by pulsation of subpapillary arteriolar and venous plexuses. Also called capillary pulse, Quincke’s sign.
