a foot with raynaud's syndrome symptoms on tips of the toes. peripheral cyanosis shown as white and discoloured toes

skin toes tips foot blood circulation disorder syndrome chilly coldness raynauds raynaud extreme freezing frostbite frostburn frostnip mountain shivering prevention artery hypotension hypovolemic insufficiency problem shock vascular venous damage disease health cold finger white blue hypothermia frost phenomenon discolored medical symptom illustration day international support swelling feet