Deep Venous Thrombosis Study Notes
Overview of Deep Venous Thrombosis (DVT)
Thrombus: A clot that forms in a vein or artery.
Thrombophlebitis: Blood clot that forms and blocks one or more veins, subdivided into:
Superficial Thrombophlebitis
Deep Venous Thrombosis (DVT)
Pathophysiology and Etiology
Venous thrombosis: A thrombus (blood clot) forms on the vein wall leading to inflammation and obstruction.
Deep Venous Thrombosis (DVT): Specifically refers to thrombosis in a deep vein of the body.
Anatomy of Deep Veins in the Leg
Deep Veins of the Leg: Critical in circulation; thrombosis in these veins can have serious consequences.
Normal Blood Flow: Ensures that oxygenated blood returns efficiently to the heart.
Embolus: A detached blood clot that can travel to other parts of the body, posing significant health risks.
Major Risk Factors for DVT
Clotting abnormalities in your family
Previous DVT: History of deep venous thrombosis increases the risk of future clots.
Surgery or Injury: Particularly post-operative states, especially involving orthopedic procedures.
Overweight: Increased body weight can contribute to venous stasis.
Use of Contraceptive Pill or Hormone Replacement Therapy: Estrogen increases clot risk.
Smoking: Contributes to vascular complications.
Pregnancy: Increases the risk of venous thromboembolism due to physiological changes.
Age: Over 40 years of age increases risk.
Clinical Manifestations
Dull/Aching Pain: Often a primary symptom.
Tenderness: Inflammation may be indicated by tenderness in the affected area.
Warmth: Localized heat may be present at the site of the clot.
Erythema: Redness of the skin overlying the affected area.
Edema: Swelling typically manifests in the leg.
Cyanosis: Bluish discoloration may occur if there is significant vascular compromise.
Complications of DVT
Chronic Venous Embolism: Long-term complications that may affect venous circulation.
Pulmonary Embolism: A serious complication where emboli travel to the lungs, potentially causing death.
Prophylactic Measures
Elevation of Legs: Reduces venous pressure.
Early Mobilization: Encourages blood flow and reduces stasis.
Leg Exercises: Enhances circulation.
Sequential Compression Devices (SCDs): Mechanical aids that promote blood flow.
Thromboembolic Deterrent (TED) Stockings: Gradient compression to assist venous return.
Pharmacologic Therapy: Use of anticoagulants as a preventative measure.
Prevention is Key: Important to avoid using pillows under knees to minimize venous obstruction.
Collaboration in Management
Diagnostic Tests: Essential for assessing DVT presence and severity.
Pharmacologic Therapy: Involves anticoagulant medications.
Surgery and Clinical Therapy: Necessary in severe cases for symptom management and clot removal.
Diagnostic Tests for DVT
Laboratory Studies: Including but not limited to:
Prothrombin Time (PT): Measures time taken for blood to clot.
Activated Partial Thromboplastin Time (aPTT): Assesses intrinsic pathway of coagulation.
International Normal Ratio (INR): Standardized measure of PT.
Platelet Count: Normal range is 150,000 to 450,000 per microliter.
D-Dimer: Elevated levels indicate breakdown of blood clots; useful in diagnosis.
Duplex Ultrasound: Radiologic test to visualize clots in veins.
Pharmacologic Therapy for DVT
Anticoagulants: Medications that prevent blood clotting.
Heparin:
Continuous infusion: Often used in acute scenarios.
Subcutaneous Heparin: Used for prophylaxis.
Monitoring: Regular monitoring of PTT and platelet counts.
Warfarin (Coumadin):
Administration: Oral, typically bridged with heparin.
Therapeutic timeframe: Takes 4-5 days to reach full effect.
INR Target: Maintain between 2.0 to 3.0 for regular therapy.
Avoid Vitamin K-rich foods during therapy (e.g., leafy greens).
Antidote: Vitamin K in case of excessive anticoagulation.
Direct Oral Anticoagulants (DOACs):
Examples: Eliquis, Xarelto, Pradaxa, which do not require routine INR monitoring.
Limitation: No specific antidote available for reversal.
Surgical Interventions for DVT
Venous Thrombectomy: Surgical removal of large clots blocking major veins.
Inferior Vena Cava (IVC) Filters:
Indicated for patients with recurrent DVT to prevent clots from reaching the pulmonary circulation.
Clinical Therapy: Acute DVT Management
Measures to Reduce Symptoms and Inflammation:
Warm, moist compresses: Applied to relieve discomfort and promote circulation.
Resting Extremity: To minimize stress on the affected leg.
Anti-Inflammatory Agents: Can reduce inflammation and pain.
Bed Rest and Elevation of Legs: Important for recovery and reduction of edema.
Avoidance of Massage: Risk of dislodging clots and causing emboli.
Nursing Assessment for DVT
Health History: Assessment for leg or calf pain and its impact on mobility.
Physical Examination: Includes checking for redness, edema, tenderness, warmth, and temperature changes. Homan's sign may be evaluated for DVT suspicion.
Nursing Diagnosis for DVT
Possible nursing diagnoses include:
Pain Management Needs
Risk for Complications: Thrombosis with potential embolization
Ineffective Tissue Perfusion
Nursing Planning Goals for DVT Management
Client will manage pain effectively to allow for rest and comfort.
Client will experience no complications, specifically that thrombosis will not embolize.
Client will exhibit increased tissue perfusion as evidenced by improved limb color and temperature.
Nursing Implementation for DVT
Pain Management: Ensure effective analgesia is administered.
Promote Peripheral Perfusion: Techniques to enhance blood circulation.
Encourage Physical Mobility: Important for recovery and prevent further thrombus formation.