Patent ID: 7483733
Filing Date: 2009-01-27
Classification: A61B

Abstract:
1. A diagnostic medical instrument adapted to determine whether a patient is suffering from a pre-shock, shock or shock-related condition, the instrument being used in a capillary filling time (CFT) test procedure in which a skin area of the patient overlying blood-filled capillaries normally imparting to the skin a pink color is depressed by a pressure, which is sufficient to expel blood from the capillaries while maintaining normal flow in the veins, said pressure causing the skin to blanch until the skin exhibits a white color, the said pressure being released when a point of maximum blanching is reached to permit blood to flow back to the capillaries at a rate that depends on the condition of the patient to cause the skin to regain its natural pink color; said instrument comprising: I. means including a color sensor trained on the skin area when exposed to light to generate a signal having a magnitude which is a function of light reflected by the skin area whose intensity depends on the natural color of the skin area, wherein the color sensor means includes means to illuminate the skin area with non-modulated light from a light source, and a light reflected therefrom is intercepted by a photodetector, which yields a signal that depends on an existing skin color; II. means responsive to said signal before pressure is applied to the skin area to determine its natural pink color to establish a reference base for the test to follow; and III. means responsive to said signal when pressure is applied to said skin during the test to measure the time elapsing from a starting point in time when the depressed skin is at its maximum blanching value of white, and the pressure applied thereon is then released to cause the capillaries to proceed to full with blood, to a final point in time when the skin recovers its natural pink color as established by the reference base, whereby the CFT measurement is an index to whether the patient is suffering from a shock-related condition, and to the severity of this condition.