stagnant hypoxia

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diminished availability of oxygen to the body tissues; its causes are many and varied and includes a deficiency of oxygen in the atmosphere, as in altitude sickness; pulmonary disorders that interfere with adequate ventilation of the lungs; anemia or circulatory deficiencies, leading to inadequate transport and delivery of oxygen to the tissues; and finally, edema or other abnormal conditions of the tissues themselves that impair the exchange of oxygen and carbon dioxide between capillaries and tissues. adj., adj hypox´ic.  

Signs and symptoms vary according to the cause. Generally they include dyspnea, rapid pulse, syncope, and mental disturbances such as delirium or euphoria. cyanosis is not always present and in some cases is not evident until the hypoxia is far advanced. The localized pain of angina pectoris due to hypoxia occurs because of impaired oxygenation of the myocardium. Discoloration of the skin and eventual ulceration that sometimes accompany varicose veins are a result of hypoxia of the involved tissues.

The treatment of hypoxia depends on the primary cause but usually includes administration of oxygen by inhalation (see oxygen therapy). In some vascular diseases, administration of vasodilators may help increase circulation, hence oxygen supply, to the tissues.
affinity hypoxia hypoxia resulting from failure of the hemoglobin to release oxygen to the tissues, as may occur with a left-shifted oxyhemoglobin dissociation curve.
anemic hypoxia hypoxia due to reduction of the oxygen-carrying capacity of the blood as a result of a decrease in the total hemoglobin or an alteration of the hemoglobin constituents.
circulatory hypoxia stagnant hypoxia.
histotoxic hypoxia that due to impaired utilization of oxygen by tissues, as in cyanide poisoning.
hypoxemic hypoxia (hypoxic hypoxia) that due to insufficient oxygen reaching the blood, as at the decreased barometric pressures of high altitudes.
stagnant hypoxia that due to failure to transport sufficient oxygen because of inadequate blood flow, as in heart failure.

stag·nant hy·pox·i·a

tissue hypoxia characterized not by tissue oligemia (tissue blood volume being normal or even increased), but by intravascular stasis due to impairment of venous outflow or (in some instances) to decreased arterial inflow.

stagnant hypoxia

An older term for the combination of reduced blood flow and poor oxygenation to a particular region of the body, especially to the brain. The term is regarded as suboptimal as it doesn’t take into account modifying local factors such as degree and duration of ischaemia, pre-existing vascular disease, blood glucose, patient age, body temperature and susceptibility of individual cells (e.g., neurones are more susceptible to permanent damage than are glial cells).