Hypoxia

The phenomenon when organs and tissues lack oxygen or the tissues are unable to utilize the oxygen present in them is called hypoxia. Hypoxia occurs quite often when any part of the system is disrupted (respiratory organs, circulatory system, nervous centers controlling respiration) supplying oxygen to the body. Hypoxia, in turn, affects other systems of the body. Based on the origin, several types of hypoxia are distinguished: exogenous, respiratory, circulatory, blood, and tissue hypoxia. Exogenous hypoxia occurs when there is a lack of oxygen in the environment. Respiratory hypoxia occurs when there is a disruption in the functioning of the respiratory organs or the center controlling them. Circulatory hypoxia arises when there is a disturbance in the general or local circulation. Blood, or hemic, hypoxia occurs when suffering from anemia or inactivating hemoglobin. Tissue, or histotoxic, hypoxia occurs when there is enough oxygen in the blood and tissues, but the tissues are unable to utilize it. For example, cyanide compounds react with trivalent iron and block cytochrome oxidase.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė