venous pooling

(noun)

When blood accumulates in the lower extremities, resulting in low venous return to the heart which can result in fainting.

Related Terms

Examples of venous pooling in the following topics:

  • Venous Blood Pressure

    • Variants of venous pressure include:
    • Jugular venous pressure (JVP), the indirectly observed pressure over the venous system.
    • Portal venous pressure or the blood pressure in the portal vein.
    • Standing or sitting for a prolonged period of time can cause low venous return in the absence of the muscle pump, resulting in venous pooling (vascular) and shock.
    • Jet pilots wear pressurized suits to help maintain their venous return and blood pressure, since high-speed maneuvers increase venous pooling in the legs.

  • Veins

    • Standing or sitting for prolonged periods can cause low venous return from venous pooling.
    • In venous pooling, the smooth muscles surrounding the veins become slack and the veins fill with the majority of the blood in the body, keeping blood away from the brain, which can cause unconsciousness.
    • Venous valves prevent back flow and ensure that blood flows in one direction.

  • Development of Blood

    • HSCs are self-renewing: When they proliferate, at least some of their daughter cells remain as HSCs, so the pool of stem cells does not become depleted.
    • The human arterial and venous systems develop from different embryonic areas.
    • While the arterial system develops mainly from the aortic arches, the venous system arises from three bilateral veins during weeks 4 to 8 of human development.

  • Blood Flow in Skeletal Muscle

    • The opposite effect would be seen if measuring venous outflow.
    • The skeletal muscles of the legs are particularly important skeletal muscle pumps as they prevent pooling of the blood in the feet and calves due to gravity.

  • Foster Pools of Expertise in Multiple Places

  • Blood Flow Through the Body

    • Thus, because skeletal muscle contraction aids in venous blood flow, it is important to get up and move frequently after long periods of sitting so that blood will not pool in the extremities.

  • Pooled standard deviation estimate (special topic)

    • In such cases, we can make our t distribution approach slightly more precise by using a pooled standard deviation.
    • The pooled standard deviation of two groups is a way to use data from both samples to better estimate the standard deviation and standard error.
    • Caution: Pooling standard deviations should be done only after careful research
    • A pooled standard deviation is only appropriate when background research indicates the population standard deviations are nearly equal.
    • When the sample size is large and the condition may be adequately checked with data, the beneļ¬ts of pooling the standard deviations greatly diminishes.

  • Venules

    • In contrast to regular venules, high-endothelial venules (HEV) are specialized post-capillary venous swellings.

  • Development of the Heart

    • The human arterial and venous systems develop from different embryonic areas.
    • While the arterial system develops mainly from the aortic arches, the venous system arises from three bilateral veins during weeks four through eight of human development.
    • The human venous system develops mainly from the vitelline veins, the umbilical veins and the cardinal veins, all of which empty into the sinus venosus.

  • Artery Function

    • The pressure in the arterial system decreases steadily, highest in the aorta and lowest in the venous system, as blood approaches the heart after delivery of oxygen to tissues in the systemic circulation.
    • Distinguish the function of the arterial system from that of venous system