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. 2019 Sep;23(Suppl 3):S172-S177.
doi: 10.5005/jp-journals-10071-23246.

Physiology of Oxygen Transport and its Determinants in Intensive Care Unit

Sumesh Arora  1 , Pratik Tantia  2
Affiliations

Physiology of Oxygen Transport and its Determinants in Intensive Care Unit

Sumesh Arora et al. Indian J Crit Care Med. 2019 Sep.

Abstract

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.

Keywords: Arterial blood gas analysis; Hemoglobin; Hyperbaric oxygen therapy; Hypoxia; Oxygen saturation; Pulse oximetry.

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Conflict of interest statement

Source of support: Nil Conflict of interest: Dr Arora is the Director of Quiz Time in Critical Care Pty Ltd, Sydney, Australia; which runs the website www.gotheextramile.com - MCQ in Critical Care. Dr Arora is not paid any salary for his work with Go the Extra Mile.

Figures

Flowchart 1
Flowchart 1
Diffusion of oxygen from plasma to RBC and binding to hemoglobin. (Drawn with permission from www.gotheextramile.com - Quiz Time in Critical Care Pty Ltd, Sydney, Australia)
Fig. 1
Fig. 1
Entry, transport in blood and metabolic role of oxygen
Fig. 2
Fig. 2
Diffusion of oxygen from alveoli to plasma (Drawn with permission from www.gotheextramile.com - Quiz Time in Critical Care Pty Ltd, Sydney, Australia)
Fig. 3
Fig. 3
Oxyhemoglobin dissociation curve and factors that results in a shift to right or left (Drawn with permission from www.gotheextramile.com - Quiz Time in Critical Care Pty Ltd, Sydney, Australia)
See this image and copyright information in PMC

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