Effect of short periods of arterial occlusion on blood flow and oxygen uptake

¹ Department of Physical Medicine and Rehabilitation, and Department of Medicine, University of Illinois College of Medicine, Chicago, Illinois

In 17 experiments, performed on the forearm of normal subjects, the effect of 2, 5, and 10 min of arterial occlusion was studied. Blood flow was obtained with the venous occlusion plethysmograph, and oxygen uptake was calculated using the Fick principle. Arterial occlusion resulted in the production of an oxygen debt which was subsequently repaid. With progressively longer periods of anoxia there was a proportionate increase in the magnitude of the debt. Similar conclusions could not be drawn from blood flow studies alone, since the vascular change represented only one means of repayment of the oxygen debt during reactive hyperemia, the other being a greater extraction of oxygen from each unit of blood early in the postocclusion period. The constant overswing on either side of the control base line, observed in the records of oxygen uptake, suggested the absence of delicately balanced and efficient checks on the mechanisms responsible for repayment of the oxygen debt incurred in the period of tissue anoxia.