The need for a simple, direct method for estimating the rate of utilization of oxygen by the tissues is obvious. A recent series of investigations1 suggests an ingenious method based on the rate at which oxyhemoglobin is reduced in the tissues. Spectroscopy of light reflected from the skin will show the characteristic absorption bands of oxyhemoglobin. Also it has been shown2 that venous compression and resulting hemostasis tend to obliterate the bands of oxyhemoglobin as it is changed to reduced hemoglobin. Under carefully controlled conditions, therefore, the rate of disappearance of the absorption bands of oxyhemoglobin might serve as an index to the rate of oxygen utilization of the skin or tissue examined and this perhaps in turn to the metabolic rate of the subject. Use was made of this principle for determining oxygen consumption by Vierordt3 in 1878.
An ingenious device for occluding the blood vessels