Jones & Bartlett Learning (JBL) Module 5 Practice Exam

In shock, the body activates the sympathetic system to preserve blood flow to vital organs. That causes peripheral arterioles to constrict, reducing blood flow to the skin. With less blood reaching the skin, it looks pale and feels cool. So pallor is a sign of peripheral vasoconstriction prioritizing core perfusion. Peripheral vasodilation would make the skin flushed, and while hypothermia can accompany shock, it isn’t the direct cause of pallor.