Phlebitis in Dogs
Phlebitis is characterized by a condition known as superficial thrombophlebitis, which refers to an inflammation of superficial veins (or veins close to the surface of the body). Phlebitis is generally due to an infection or because of thrombosis -- the formation of a clot (or thrombus) inside a blood vessel, which in turn obstructs the flow of blood in the body.
Superficial venous thrombophlebitis is the most common form of this condition, and is usually localized in one area.
Conversely, deep tissue thrombophlebitis is associated with clinical signs of sepsis, in which a bacterial infection occurs due to the presence of pathogenic organisms and their toxins in the blood or tissues. This type of thrombophlebitis is also associated with deep tissue thromboembolism, in which a clot or thrombus formed in one part of the body breaks free and migrates to another blood vessel, where it causes blockage.
Phlebitis can affect both dogs and cats. If you would like to learn more about how this disease affects cats, please visit this page in the PetMD health library.
Symptoms and Types
The main symptom of phlebitis is a localized inflammation, which is characterized by warmth, swelling, pain, hardened vessels, or a redness of the skin known as erythema. If at least two of the aforementioned signs are present, this can be taken as a sign of local inflammation. Drainage or fever may also be present, both being associated with the body's response to such infections.
There is no specific age, breed, or gender of dog that is known to be more susceptible to the development of phlebitis. However, very young or elderly dogs may be at higher risk simply due to a less developed or poorly functioning immune system.
Other characteristics that are considered risk factors for the development of phlebitis include obesity, lack of mobility, poor vein quality, chronic heart or kidney disease, pregnancy, and/or an immunodeficiency disorder in which the dog's immune system does not function properly.
The main cause of phlebitis is intravenous (IV) catheter use. Poor catheter quality or care may lead to bacterial colonization of a catheter, which can then infect the dog. Catheters are often used during surgery, or in emergency situations for treating trauma victims.
A number of diagnostic procedures are necessary for properly diagnosing phlebitis. The Doppler test is an inexpensive means for testing blood flow in the dog's veins, and may reveal any blood circulation irregularities and blockage. Blood cultures may also indicate signs associated with systematic inflammations. Additional diagnostic techniques may include x-ray imaging and urine analysis.
If infection is suspected, antibiotic treatment will be the most likely treatment. The specific antibiotic prescribed to your dog will depend on the location of the infection, as well as the suspected contaminants behind the infection (if no culture is available at the time). Additional medications may help to make your dog more comfortable by alleviating related symptoms.
Living and Management
After the initial treatment, antibiotic therapy should be adjusted based on the follow-up culture tests. Certain veins, known as phlebotic veins, should be avoided for IV therapy or blood collection until your dog has completely recovered. With proper antibiotic treatment, the most severe cases may still take up to three weeks to resolve.
Because the main cause of phlebitis is poor quality catheters or improper catheter care, this is the primary area to target when thinking about prevention. Any IV catheter sites should be cleaned regularly with antimicrobials and treated with antimicrobial ointment, in order to avoid bacterial infection that may lead to phlebitis. Sterile dressings should be used, and catheters should be changed within 24 hours, especially if they were placed in an emergency situation. Longer catheters may reduce the incidence of phlebitis.