Tissue hypoxia: implications for the respiratory clinician

Respir Care. 2014 Oct;59(10):1590-6. doi: 10.4187/respcare.03357. Epub 2014 Aug 26.


Oxygen is essential for normal aerobic metabolism in mammals. Hypoxia is the presence of lower than normal oxygen content and pressure in the cell. Causes of hypoxia include hypoxemia (low blood oxygen content and pressure), impaired oxygen delivery, and impaired cellular oxygen uptake/utilization. Many compensatory mechanisms exist at the global, regional, and cellular levels to allow cells to function in a hypoxic environment. Clinical management of tissue hypoxia usually focuses on global hypoxemia and oxygen delivery. As we move into the future, the clinical focus needs to change to assessing and managing mission-critical regional hypoxia to avoid unnecessary and potential toxic global strategies. We also need to focus on understanding and better harnessing the body's own adaptive mechanisms to hypoxia.

Keywords: alveolar ventilation; diffusion; hemoglobin binding; hemoglobin-oxygen binding; hypoxemia; hypoxia; hypoxia-inducible factors; oxygen extraction; oxygen utilization; regional oxygenation; ventilation/perfusion matching.

Publication types

  • Review

MeSH terms

  • Adaptation, Physiological
  • Humans
  • Hypoxia / etiology
  • Hypoxia / physiopathology*
  • Hypoxia / therapy*
  • Oxygen / blood*
  • Oxygen Inhalation Therapy


  • Oxygen