Ads
related to: veins used to draw blood
Search results
Results From The WOW.Com Content Network
An elastic tourniquet used to temporarily restrict blood flow. The tourniquet distends the veins, making them more palpable and visible.. There are many ways in which blood can be drawn from a vein, and the method used depends on the person's age, the equipment available, and the type of tests required.
It arises from the cephalic vein 2.5 cm (one inch) below the lateral epicondyle of the humerus, runs obliquely upward and medially, and empties into the basilic vein 2.5 cm (one inch) above the medial epicondyle. It is routinely used for venipuncture (taking blood) and as a site for an intravenous cannula.
Phlebotomy is the process of making a puncture in a vein, usually in the arm, with a cannula for the purpose of drawing blood. [1] The procedure itself is known as a venipuncture, which is also used for intravenous therapy.
Veins become more visually prominent when lifting heavy weight, especially after a period of proper strength training. Physiologically, the superficial veins are not as important as the deep veins (as they carry less blood) and are sometimes removed in a procedure called vein stripping, which is used to treat varicose veins.
Though veins might make it appear as such, human blood is never naturally blue. [3] The blue appearance of surface veins is caused mostly by the scattering of blue light away from the outside of venous tissue if the vein is at 0.5 mm deep or more. Veins and arteries appear similar when skin is removed and are seen directly. [4] [5]
In the systemic circulation the return is of deoxygenated blood from the organs and tissues of the body, and in the pulmonary circulation the pulmonary veins return oxygenated blood from the lungs to the heart. Almost 70% of the blood in the body is in the veins, and almost 75% of this blood is in the small veins and venules. [7]
The name is most likely derived from phlebotome: phlebos, Greek for blood vessel and tome, meaning to cut. [2] These instruments are the progression from the early use of fish teeth, sharpened stones, and thorns used to penetrate blood vessels. The earliest known examples are made of bronze with a myrtle-leaf shape to the blade.
Venous access is any method used to access the bloodstream through the veins, either to administer intravenous therapy (e.g. medication, fluid), parenteral nutrition, to obtain blood for analysis, or to provide an access point for blood-based treatments such as dialysis or apheresis.