Facts about Veins
Most veins in the body carry deoxygenated blood from the tissues back to the heart, with the exception of the pulmonary and umbilical veins.
Veins are in contrast to the arteries, which are muscular blood vessels that carry blood away from the heart to the cells, tissues, and organs of the body.
The pulmonary veins carry relatively oxygenated blood from the lungs to the heart.
Incompetence of this vein is an important cause of varicose veins of lower limbs.
The total capacity of the veins in humans is more than sufficient to hold the entire blood volume of the body.
A variety of treatments are used depending on the patient's particular type and pattern of veins and on the physician's preferences.
The most common vein disorder is venous insufficiency, usually manifested by spider veins or varicose veins.
Like the arteries, the veins are defined by their three-layer walls, but the vein walls are less muscular and thinner than the artery walls.
The precise location of veins is much more variable from person to person than that of arteries.
The difference between veins and arteries is their direction of flow (out of the heart by arteries, returning to the heart for veins), not their oxygen content.
Skeletal muscle contractions help move the blood through the veins.
A portal venous system is a series of veins or venules that directly connect two capillary beds.
Veins are in contrast to the arteries, which are muscular blood vessels that carry blood away from the heart to the cells, tissues, and organs of the body.
The arteries are perceived as carrying oxygenated blood to the tissues, while veins carry deoxygenated blood back to the heart.
Excepting the pulmonary vein, veins function to return deoxygenated blood to the heart and are essentially tubes that collapse when their lumens are not filled with blood.
The helical bands of smooth muscles that wrap around veins help maintain blood flow to the right atrium.
Some highly concentrated fluids or irritating medications must flow into the large central veins, which are sometimes used when peripheral access cannot be obtained.