Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:
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- Inadequacy of the venous valves that causes impaired venous drainage leading to edema of the lower extremities.
- A chronic condition of lower extremity vascular incompetence.
- Normal blood flow in the venous system is unidirectional from the superficial veins to the deep veins.
- Unidirectional flow is maintained by contraction of leg muscles and by valves within the veins.
- Damage to the valves, e.g. following DVT, causes them to become rigid and they lose their ability to prevent retrograde blood flow properly.
- Decreased venous return from lower extremities causes increased pressure and distention of the veins, which in turn causes separation of the valve leaflets.
- Increased pressure transmitted into the dermal microcirculation results in extravasation of macromolecules and red blood cells causing inflammatory injury resulting in ulcer formation, skin changes, and poor ulcer healing.
- Primary valve incompetence (most common)
- Deep vein thrombosis (DVT)
- Risk factors include advanced age, family history, smoking, sedentary lifestyle, obesity, lower extremity trauma, prior DVT, and pregnancy