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Peripheral Vasculature Diseases – Section 4 VENOUS DISEASE (p. 339-345)
General Info about veins and such…
Veins: high-capacitance vessels that carry blood from the capillaries toward the heart; have thinner walls than arteries; often have one-way valves at intervals to prevent reflux of the blood, which flows in a steady stream and is in most cases dark-colored due to the presence of reduced hemoglobin.
Veins hold more than 70% of the total blood volume.
They’re not as muscular in structure as the arteries are…
The subendothelial layer of veins is thin
Compared to arteries, tunica media has fewer, smaller bundles of smooth muscle cells intermixed with reticular and elastic fibers.
Note that as this section is part of the Peripheral Vasculature Diseases, the veins we will discuss are mostly veins in the extremities! That said…
Veins of extremities have intrinsic vasomotor activity, but transport of blood back to the heart does require external compression from surrounding skeletal muscles as well as one-way valves to keep the blood moving toward the heart.
Deep vs. Superficial Veins of the Extremities:
Course in body…
Deep Veins generally course along the arteries and
return blood to the heart
Superficial Veins located subcutaneously and eventually drain into the deeper veins through a perforating connectors
This study guide will follow the book by breaking Venous Diseases down into three sub-types: 1/ Varicose Veins 2/ Venous Thrombosis – Deep Venous Thrombosis 3/ Venous Thrombosis – Superficial Thrombophlebitis