Peripheral Circulatory and Metabolic Consequences of Thyrotoxicosis: VI. The Effect of Cold Water Immersion upon the Circulation in the Hands of Patients with Thyrotoxicosis before and after Treatment

Abstract

Skin temperature of the hand was studied after immersion in water of different low temoeratures in patients with thyrotoxicosis before and after treatment.

Skin temperature was considerably higher in thyrotoxicosis at all water temperatures. This was the case during initial vasoconstriction as well as during and after cold vasodilatation. Calorimetry after cold vasodilatation at the lowest water temperature showed that hand blood flow under these conditions was twice as high in thyrotoxicosis as in the normal state. Cold vasodilatation took place at higher water temperatures in thyrotoxicosis, and the tendency to ‘hunting’ was more pronounced than in the normal state.

It was concluded that the thyrotoxic state represents a strong impulse to vasodilatation in the skin even at low local temperatures. This is probably an expression of the general physiological phenomenon that the thermal state of the body determines the tolerance of skin vessels to cold.

Key Words:

• Thyrotoxicosis
• blood flow
• body temperature regulation