Phlebitis stages refer to a grading system that indicates the severity of inflammation in a vein due to an intravenous (IV) catheter. The score ranges from 0–4.

Symptoms in the early stage involve redness and pain at the IV site. If the condition progresses to the advanced stage, additional symptoms include swelling and a palpable venous cord, which is firmness in the vein.

In the early stage, doctors recommend removing the IV device and inserting a new one in another site. If phlebitis reaches the medium stage, they advise considering treatment.

One treatment may entail topical anti-inflammatory medications for people to apply to the skin over the vein. Another treatment option is an oral medication to reduce the formation of blood clots.

Keep reading to learn more about phlebitis stages due to IV therapy, causes, diagnosis, treatment, and outlook.

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Phlebitis is the inflammation of a vein, which results in redness, swelling, and pain. It can happen in an arm when a person receives IV therapy in a hospital.

The condition may also occur from a blood clot. When this happens, it is called thrombophlebitis. This may affect veins near the surface of the skin or deeper veins, but it usually occurs in the leg.

The staging system only applies to phlebitis due to IV therapy, a method of putting fluids into the bloodstream. It involves inserting a tube called a cannula into a vein. Approximately 25–35% of people who receive IV therapy in a hospital acquire phlebitis, notes an older 2002 study.

The chart below shows the phlebitis staging scale for IV therapy.

StageDescription
Score of 0.The IV site looks healthy.
Score of 1.The IV site looks slightly red, and a person experiences slight pain near the site.
Score of 2, or early-stage phlebitis.Redness and pain at the IV site are present.
Score of 3, or medium stage phlebitis.Redness, swelling, and pain along the path of the IV cannula are present.
Score of 4, or advanced stage phlebitis.Signs include redness, swelling, a palpable venous cord, and pain along the path of the IV cannula.

Causes of phlebitis include:

  • infection
  • injury
  • irritation

The use and removal of an IV can lead to these causes. A 2016 study explains that IV-related phlebitis may stem from:

  • Mechanical damage: This may happen when movement of the IV cannula inside a vein produces friction. It can also be due to irritation when a cannula is too wide for a vein.
  • Chemical damage: This may occur when a drug or other component of fluid flowing through an IV has a characteristic that produces vein irritation.
  • Infection: In response to IV insertion, bacteria may infiltrate a vein. This can create serious complications if the infection develops into sepsis. In sepsis, the infection leaves the IV site and becomes systemic, or circulates throughout the body.

Aside from IV therapy, thrombophlebitis can cause injury or trauma to a vein. If it affects a vein close to the skin surface, doctors call this superficial thrombophlebitis.

Risk factors for surface thrombophlebitis include:

If phlebitis involves an IV site, a diagnosis may be evident by observing the symptoms.

In contrast, if symptoms suggest superficial thrombophlebitis, the following procedures are necessary for diagnosis:

  • Physical examination: This entails noting any symptoms of redness, warmth, and tenderness over the track of a surface vein, along with a palpable cord.
  • Medical history: This includes discovering whether a person has risk factors or conditions that may cause injury to a vein.
  • Ultrasound: This imaging test can show the extent of superficial thrombophlebitis. It may also determine whether it has developed into the complication of deep vein thrombosis, a blood clot in a deep vein.
  • D-dimer blood test: This test measures a protein fragment that results when a blood clot dissolves. As the level of D-dimer is not always higher than normal in superficial thrombophlebitis, its use is limited.

Treatment of IV-related phlebitis differs from the treatment of superficial thrombophlebitis.

Treatment for IV-related phlebitis

In the early stage, experts recommend removing the IV and inserting a new one in a different site. Once phlebitis reaches the medium stage, they also advise considering treatment.

A 2015 review evaluated the effectiveness of treatments for IV-related phlebitis. Due to limited, poor-quality data, the authors concluded that research is too preliminary to determine how well current treatments work. However, options include:

  • Topical treatments. Examples include a nonsteroidal anti-inflammatory drug such as diclofenac gel (Voltaren) or a medication to reduce swelling of inflamed veins such as heparinoid (Hirudoid).
  • Nonsteroidal anti-inflammatory drugs: These decrease inflammation and include medications, such as ibuprofen.

Treatment for superficial thrombophlebitis

Research from 2018 reports that most cases of superficial thrombophlebitis resolve on their own. Treatment may involve:

  • elevating the leg above the heart to reduce swelling
  • wearing elastic stockings
  • applying warm compresses to the area
  • using topical or oral anti-inflammatory medications

If superficial thrombophlebitis is more severe, treatment may include an anticoagulant, such as fondaparinux (Arixtra).

When the cause of the condition is an infection, in rare cases, treatment may necessitate surgical removal of the infected part of the vein.

Cases of phlebitis from an IV infusion can range from those involving mild discomfort to those with severe complications, such as sepsis. The outlook depends on the severity.

Phlebitis stages are a grading system that doctors use to diagnose and monitor the severity of inflammation of a vein associated with IV therapy.

Doctors do not use phlebitis stages to diagnose the severity of thrombophlebitis. Instead, the diagnostic process involves a physical exam, history, and ultrasound.

There are some differences in treatment between IV-related phlebitis and thrombophlebitis. Yet both conditions may entail treatment with nonsteroidal anti-inflammatory drugs or anticoagulants.