Fig. 2From: Biological effects of the oxygen molecule in critically ill patientsDiffusion of an oxygen molecule from the arterial end of a capillary to tissue cells. PO2 in the interstitial fluid averaged 40 mmHg, and that in the cells was 23 mmHg, ranging from 5 to 40 mmHg. (Reuse from Guyton and Hall Textbook of Medical Physiology 14th ed. with permission from Elsevier B.V.)Back to article page