Oxygen Transport and Tissue Utilization

Tissue oxygenation and regulation is a critical feature for any organ function. The maintenance of an adequate supply of oxygen is required to maintain normal cellular function. This requires the coordinated action of the three major systems involved in oxygen transport: the cardiovascular system, the respiratory system, and the blood. The cardiovascular and respiratory systems are designed to carry the oxygen that is present in the atmosphere down to the mitochondria. The majority of oxygen is transported to the tissues bound to hemoglobin, and its equilibrium is a function of arterial oxygen content, hemoglobin level, arterial oxygen partial pressure, arterial oxygen saturation, and cardiac output. The interplay among these factors determines the transport of oxygen to the tissues defining its convection and diffusion properties. The resuscitation of patients with hemodynamic dysfunction is more than normalizing hemodynamics as an approach like that might prove to be inadequate, but also the therapies might have inherent negative effects. Therefore, the management of a patient in shock with the theoretical concepts of the main drivers for transport of oxygen and the subsequent delivery of oxygen to the tissues might lead to a structured approach that might benefit the patient more than using static clinical endpoints for these variables.