This conservation response involves an extensive system of nerves and muscles to control blood flow through the smaller blood vessels in the skin. With Raynaud's phenomenon, this control system becomes hyper sensitive to cold and overcompensates in reducing the blood flow to the fingers. Raynaud's phenomenon may be caused by damage to either the muscles or nerves that control blood flow. Signs and Symptoms Poor blood circulation in the fingers is the most noticeable symptom of Raynaud's phenomenon. Activities resulting in cold exposure like washing the car, holding a cold steering wheel, or the cold handlebars of a bicycle will bring on the symptoms.
Attacks can also occur when a person is outdoors in the cold weather.
The fingers turn white and there is pain. Sometimes there is redness that accompanies the return of blood circulation after 30 minutes to two hours. Occupationally induced Raynaud's phenomenon gets worse if workers remain exposed to the same conditions that caused the problem. As it gets worse, the attacks become stronger and more frequent. It is very important to recognize the signs and symptoms while it is developing.