Physiology of Oxygen Transport and its Determinants in Intensive Care Unit

Transport of oxygen is one of the most important functions of blood. How oxygen moves from the air, where its partial pressure is about 150 mm Hg to mitochondria, where it drops down to a single digit is an evolutionary marvel. In this article, we discuss the physiology of oxygen transport from the alveoli to the tissue, the alveolar gas equation and the oxyhemoglobin dissociation curve. In the applied physiology section, we discuss the impact of high altitude, hyperbaric conditions, carbon monoxide poisoning on the transport of oxygen. Some common pitfalls in the interpretation of pulse oximetry and arterial blood gas are also discussed. Finally, we talk about the methods of increasing oxygen delivery, the compensation for hypoxia and some indications of venous oxygen saturation measurement. HOW TO CITE THIS ARTICLE: Arora S, Tantia P. Physiology of Oxygen Transport and its Determinants in Intenstive Care Unit. Indian J Crit Care Med 2019;23(Suppl 3):S172–S177.