Phlebitis

Introduction

Phlebitis is the inflammation of a vein, which can occur in superficial or deep veins and may be associated with pain, redness, and swelling. It is an important clinical condition as it can lead to complications such as thrombosis and infection. Early recognition and appropriate management are essential to prevent serious outcomes.

Definition and Classification

Definition of Phlebitis

Phlebitis refers to the inflammation of the venous wall, which may occur with or without the formation of a thrombus. It can affect any vein in the body but is most commonly observed in the lower limbs and in veins subjected to trauma or intravenous therapy.

Classification

• Superficial Phlebitis: Inflammation of veins located near the skin surface, often causing pain, redness, and a palpable cord.
• Deep Vein Thrombophlebitis (DVT): Involves veins located deeper within the limb and may be associated with thrombus formation, posing a risk of pulmonary embolism.
• Acute Phlebitis: Rapid onset inflammation of the vein, usually lasting a few days to weeks.
• Chronic Phlebitis: Persistent or recurrent vein inflammation, sometimes associated with venous insufficiency or varicosities.
• Primary Phlebitis: Occurs spontaneously without an identifiable underlying cause.
• Secondary Phlebitis: Develops due to underlying factors such as infection, trauma, intravenous therapy, or hypercoagulable states.

Etiology and Risk Factors

Infectious Causes

• Bacterial Infections: Phlebitis can result from bacterial invasion of the vein wall, commonly caused by Staphylococcus aureus or Streptococcus species.
• Septic Phlebitis: Severe infection of the vein, often associated with systemic symptoms such as fever, chills, and malaise.

Non-Infectious Causes

• Trauma or vein injury, such as from intravenous cannulation or catheter placement
• Prolonged immobilization leading to stasis of blood in veins
• Hypercoagulable states increasing the risk of thrombus formation

Underlying Medical Conditions

• Varicose veins that predispose to venous inflammation
• Malignancy, which increases the risk of thrombophlebitis
• Pregnancy, due to hormonal changes and increased venous pressure
• Inherited or acquired thrombophilia

Medications and IV Therapy

• Intravenous drugs or irritant solutions that can damage the vein wall
• Chemotherapy agents causing endothelial irritation
• Hormonal therapies that may increase clotting risk

Pathophysiology

• Inflammatory Cascade: Injury to the vein wall triggers release of inflammatory mediators, leading to redness, pain, and swelling.
• Virchow’s Triad: Endothelial injury, venous stasis, and hypercoagulability contribute to thrombus formation in affected veins.
• Thrombus Formation: In some cases, inflammation promotes blood clot development within the vein, increasing the risk of deep vein thrombosis and embolism.

Clinical Presentation

Symptoms

• Localized Pain and Tenderness: Patients often report pain along the course of the affected vein, which may worsen with movement or palpation.
• Redness and Warmth: The overlying skin may appear erythematous and feel warm to touch.
• Swelling: Mild to moderate edema may occur in the affected limb, especially in cases involving superficial veins.
• Fever: Low-grade fever may be present in infectious or septic phlebitis.

Physical Examination Findings

• Palpable Cord: A firm, tender, cord-like structure along the vein is often noted in superficial phlebitis.
• Skin Changes: Erythema, warmth, and sometimes mild induration over the vein.
• Edema: Swelling may be present distal to the affected vein, particularly if thrombus formation is involved.

Diagnostic Evaluation

History Taking

• Onset, duration, and progression of pain and tenderness
• Recent intravenous therapy, catheter use, or trauma to the limb
• Past medical history including previous thrombotic events or varicose veins
• Risk factors for hypercoagulability or infection

Laboratory Investigations

• Complete blood count to assess for leukocytosis
• Inflammatory markers such as ESR and CRP
• Blood cultures in cases of suspected septic phlebitis

Imaging Studies

• Duplex ultrasonography to evaluate vein patency, detect thrombus, and assess flow
• Venography, rarely used, for detailed venous mapping
• MRI or CT venography for complex cases involving deep veins or atypical anatomy

Differential Diagnosis

• Cellulitis: Infection of the skin and subcutaneous tissue causing redness, warmth, and tenderness but lacking a palpable cord along the vein.
• Superficial Thrombophlebitis vs Deep Vein Thrombosis: Distinguishing between superficial and deep vein involvement is critical due to the risk of pulmonary embolism with DVT.
• Lymphangitis: Inflammation of lymphatic vessels, often presenting with red streaks extending from the infection site toward regional lymph nodes.
• Musculoskeletal Pain or Contusion: Localized tenderness without vascular involvement may mimic phlebitis symptoms following trauma.

Management

Non-Pharmacological Management

• Elevation of the affected limb to reduce swelling and improve venous return
• Application of warm compresses to relieve pain and improve circulation
• Compression therapy with elastic bandages or stockings for support
• Encouraging activity and early mobilization to prevent stasis

Pharmacological Management

• Nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce pain and inflammation
• Anticoagulation therapy in high-risk cases or when deep vein involvement is suspected
• Antibiotics for confirmed or suspected infectious phlebitis

Surgical or Interventional Management

• Vein ligation or excision in recurrent or refractory superficial phlebitis
• Thrombectomy in cases of extensive thrombus or risk of embolization

Complications and Prognosis

• Extension to Deep Veins: Superficial phlebitis may progress to involve deep veins, increasing the risk of deep vein thrombosis.
• Pulmonary Embolism: Thrombus formation in deep veins can dislodge and travel to the lungs, causing life-threatening complications.
• Sepsis: Infectious phlebitis may lead to systemic infection if not treated promptly.
• Post-Thrombotic Syndrome: Chronic pain, swelling, and skin changes may persist after deep vein involvement.

Prevention

• Proper intravenous catheter care and aseptic technique during insertion and maintenance
• Early mobilization of hospitalized or immobilized patients to prevent venous stasis
• Use of compression stockings in patients at risk for venous thromboembolism
• Management of underlying hypercoagulable conditions and risk factors such as obesity or varicose veins

References

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