This text is dedicated to a subtype of venous disorders. General article about venous diseases can be found here.
Phlebitis means inflammation of the veins. It is a relatively common condition that may affect any veins, but it most commonly occurs in the superficial venous system of the lower extremities and in hospitalized patients, we also frequently see phlebitis of upper extremities.
Given that phlebitis is most closely related to the venous system of the lower limbs, it is necessary to say few words about its anatomy and function. The venous blood from the lower extremities is drained by two venous systems – the superficial and deep veins. The deep system is able to transport larger amount of blood and it is connected to the surface system with connecting veins. The veins of the lower limbs are equipped with one-way flaps that allow the blood to flow in only one direction (out o the limbs). The connecting veins have also valves that allow one-way blood flow from the superficial venous system to the deep veins and not in the opposite direction. In addition to the valves, the proper blood flow is ensured by the local muscle pump. Contractions of local muscles compress the veins and push the blood in the right direction.
As mentioned above, the classical phlebitis (or thrombophlebitis) affects the superficial veins. Deep venous system may be inflamed as well, but it is usually accompanied with blood clots formation and we refer this condition to as the deep vein thrombosis.
There are many causes of phlebitis. The venous inflammations are more typical in people with chronic venous insufficiency and varicose veins, in users of hormonal contraception and in smokers. Recurring phlebitis may be also paraneoplastic sign, i.e. it may accompany malignant diseases and it may also occur in congenital thrombophilic states such as the Factor V Leiden. Specific causes of thrombophlebitis in hospitalized patients are intravenous cannulae. If phlebitis occurs, the cannula must be immediately removed.
Superficial thrombophlebitis is seen as local redness in course of the affected vein (i.e. it is usually stripe-shaped) and local pain. The body temperature may be only slightly elevated, but the extremity is usually not swollen.
The inflammation can be seen by the naked eye, but it is advisable to perform a local ultrasound to rule out the deep vein thrombosis. In case of recurring phlebitis, it is advisable to exclude common thrombophilias (in younger patients) or malignant disease (in older patients).
The phlebitis is treated by local anti-inflammatory drugs in form of gels and ointments. It is also advisable to prescribe some anticoagulants at least in reduced dose to prevent the progress into the deep vein thrombosis (LMWHs are the drugs of choice). Supportive therapy may include venotonic drugs. When there is a large phlebitis, it is advisable to prescribe antibiotics.