This test looks for reduced blood flow in the fingers after they are exposed to cold temperatures.
A cold stimulation test may be advised when a healthcare provider suspects Raynaud phenomenon. This condition causes the small arteries of the fingers, toes, ears, or nose to go into spasm. The spasm causes changes in skin color. Feelings of numbness and pain also often occur. Cold temperatures or emotional stress can bring on symptoms of Raynaud phenomenon. When this condition lasts for 2 years or more and an underlying cause cannot be found, it is called Raynaud disease. The cold stimulation test is used to see if a person's symptoms are from Raynaud phenomenon or other causes of low blood flow, such as atherosclerosis.
A heat sensor is attached to the person's fingers to measure their normal temperature. Then, each finger is chilled with cold water or some other device. The fingers are removed from the cold after a short period of time. The skin temperature of the fingers is measured every 5 minutes until it returns to normal.