PANCE - Pulmonary Embolism and Deep Vein Thrombosis

Here are key facts for Physician Assistant National Certifying Examination (PANCE) from the Pulmonary Embolism & Deep Vein Thrombosis tutorial, focusing on clinical recognition, diagnosis, and management that are essential for certification. See the tutorial notes for further details and relevant links.

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1. Venous Thromboembolism: DVT and PE commonly occur together; the term "venous thromboembolism" describes their combined condition. 2. PE Mechanism: Pulmonary embolism occurs when pulmonary arteries are obstructed, most often by emboli that travel from deep veins of thighs/pelvis. 3. Pathogenesis Process: Clot forms in deep vein → fragment breaks off → travels through IVC → right heart → pulmonary arteries → obstructs blood flow → impairs gas exchange. 4. Nonthrombotic Sources: Air, fat, amniotic fluid, bacterial (septic), foreign bodies, and tumors can also cause PE. 5. Complications: Pulmonary hypertension, right heart failure, and pulmonary infarction; PE is a leading cause of cardiovascular-related death. 1. Endothelial Injury:

• Fracture, surgery, trauma, or previous DVT
• Triggers clotting cascade when endothelium is damaged
• Smoking also associated with endothelial damage

2. Venous Stasis:

• Immobility (bed rest, long flights)
• Elevated central venous pressure
• Heart failure
• Obesity

3. Hypercoagulable States:

• Pregnancy and postpartum period (pregnancy also associated with IVC stasis)
• Cancer
• Hormonal medications (contraceptives, replacement therapies)
• Coagulation disorders (Factor V Leiden)

4. Multiple Risk Factors: Patients with several predisposing elements have significantly higher risk (e.g., pregnant women on bed rest). 5. Preventable Factors: Many risk factors are modifiable through preventive interventions. 1. DVT Presentation:

• Unilateral leg swelling, tenderness, venous dilation
• Can occur in upper body (less common)
• May be asymptomatic
• Post-thrombotic syndrome if venous valves are damaged

2. PE Symptoms:

• Dyspnea, tachypnea (rapid breathing)
• Chest pain
• Hypoxemia and ventilation-perfusion mismatch
• Respiratory alkalosis
• Tachycardia
• Right heart failure possible

3. Atypical Presentations: Altered mental state particularly important to recognize in elderly patients. 4. PE Classifications:

• By risk: massive (high risk), intermediate (submassive), low risk
• By location: saddle (at pulmonary trunk bifurcation), lobar, segmental, subsegmental

5. Pulmonary Infarction: Most often due to small emboli causing tissue ischemia, typically in lower lobes. 1. Clinical Probability Assessment:

• Wells Score for DVT: Based on swelling, edema, likelihood of alternative diagnosis
• Wells Score for PE: ≥4 indicates PE likely; <2 low probability, 2-6 moderate, >6 high probability

2. Laboratory Testing:

• D-dimer: >500 ng/mL indicates possible PE/DVT requiring further testing
• Useful to rule out low-probability cases

3. Imaging for PE:

• Chest CT with angiography: Most widely used; visualizes pulmonary arterial disruption
• Ventilation-perfusion scan: Non-invasive test for blood clot detection
• Chest X-ray: May show atelectasis, Hampton hump (pulmonary infarction), Westermark sign (oligemic areas), pleural effusion

4. Imaging for DVT:

• Venous ultrasonography with compression: Verifies thrombus presence
• Contrast venography: Alternative method

5. Additional Findings:

• ECG: May show sinus tachycardia; S1Q3T3 pattern (S wave in lead I, inverted Q and T waves in lead III)
• Thrombi characteristics: Premortem thrombi display lines of Zahn (layers of fibrin, RBCs, platelets)

1. Supportive Therapy:

• Oxygen administration when saturation <90%
• Saline for fluid management
• Vasopressors if hemodynamically unstable

2. Anticoagulation:

• Short-term: Heparin, enoxaparin, or fondaparinux
• Long-term: Warfarin
• Monitoring: Assess for complications including heparin-induced thrombocytopenia

3. Advanced Interventions:

• Embolectomy or clot dissolution for severe cases to restore pulmonary arterial flow

4. DVT Prophylaxis:

• Mechanical: Sequential compression devices (SCDs) to prevent venous stasis
• Pharmacologic: Low-dose enoxaparin or heparin in selected patients

5. Long-term Management: Risk factor modification, monitoring for post-thrombotic syndrome.

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1. When to Suspect DVT: Unilateral leg swelling, tenderness, venous dilation; may be asymptomatic. 2. When to Suspect PE: Unexplained dyspnea, tachypnea, chest pain, hypoxemia; altered mental status in elderly. 3. Risk Assessment: Identifying patients with multiple Virchow's Triad elements who require heightened vigilance. 4. Diagnostic Challenges: PE diagnosis can be difficult due to nonspecific symptoms and signs. 5. Clinical Probability Interpretation: Utilizing Wells Scores appropriately to guide further testing. 1. D-dimer Utilization: Rule-out test for low-probability cases; levels >500 ng/mL warrant further investigation. 2. Imaging Selection:

• CT angiography as first-line for suspected PE
• Ultrasonography with compression for suspected DVT

3. Chest X-ray Findings:

• Hampton Hump: Wedge-shaped shadow indicating pulmonary infarction, typically in lower lobes
• Westermark Sign: Focal oligemia appearing as area of poor perfusion

4. ECG Pattern Recognition: Sinus tachycardia common; S1Q3T3 pattern may be present but nonspecific. 5. PE Classification Importance: Location (saddle, lobar, segmental, subsegmental) and risk level (massive, submassive, low) guide management. 1. Anticoagulation Initiation: When to start therapy based on clinical suspicion and risk assessment. 2. Supportive Care Decisions: Oxygen, fluid, and hemodynamic support based on presentation. 3. Advanced Intervention Selection: Determining candidates for embolectomy or thrombolysis. 4. Prophylaxis Decision-Making: Identifying high-risk patients requiring preventive measures. 5. Monitoring Requirements: Appropriate surveillance for treatment efficacy and complications. 1. Mechanical Prophylaxis: Sequential compression devices (SCDs) prevent venous stasis in hospitalized patients. 2. Pharmacologic Prophylaxis: Low-dose anticoagulants (enoxaparin or heparin) for selected high-risk patients. 3. Early Mobilization: Encouraging movement to prevent stasis when appropriate. 4. Patient Education: Teaching about risk factors and preventive measures. 5. Risk Factor Modification: Addressing modifiable elements of Virchow's Triad. 1. Pulmonary Infarction: Small emboli causing tissue ischemia; Hampton Hump on X-ray. 2. Pulmonary Hypertension: Can result from PE; monitor for signs of right heart strain. 3. Right Heart Failure: PE complication requiring prompt intervention. 4. Heparin-Induced Thrombocytopenia: Serious complication of anticoagulant therapy. 5. Post-thrombotic Syndrome: Long-term DVT complication from venous valve damage.

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Below is information not explicitly contained within the tutorial but important for the Physician Assistant National Certifying Examination. 1. Acute Coronary Syndrome: Chest pain, dyspnea, ECG changes; distinguishing features include cardiac biomarkers. 2. Pneumonia: Fever, productive cough, focal findings on exam and imaging; may coexist with PE. 3. Aortic Dissection: Tearing chest pain, pulse deficits, widened mediastinum on imaging. 4. Pneumothorax: Sudden-onset pleuritic pain, decreased breath sounds, hyperresonance. 5. Musculoskeletal Pain: Reproducible with palpation, normal oxygenation, no risk factors for PE. 1. Direct Oral Anticoagulants: Role in PE/DVT treatment, advantages and limitations. 2. Thrombolytic Therapy: Indications, contraindications, and administration protocols. 3. Bridging Anticoagulation: Management during transitions of therapy. 4. Inferior Vena Cava Filters: Indications, placement, and removal considerations. 5. Anticoagulation in Special Populations: Renal dysfunction, pregnancy, cancer, obesity. 1. Silent PE: May be present without typical symptoms, especially in elderly or chronically ill. 2. Upper Extremity DVT: Consider in patients with central venous catheters, pacemakers, or IV drug use. 3. Saddle Embolus: Often causes significant hemodynamic compromise requiring aggressive management. 4. Subsegmental PE: Management controversies regarding anticoagulation necessity. 5. Wells Score Limitations: Clinical judgment remains essential, as scoring systems have limitations. 1. CT Angiography Technique: Contrast timing, breath-holding, and interpretation pearls. 2. Ultrasound Technical Aspects: Compression techniques, Doppler assessment, limitations. 3. Arterial Blood Gas Sampling: Technique, interpretation, and integration with clinical findings. 4. Central Line Placement: Avoiding complications in patients on anticoagulation. 5. Thrombolytic Administration: Monitoring protocols and emergency response to complications. 1. Anticoagulation Duration: Risk-based approach to determining treatment length. 2. Recurrent VTE Prevention: Strategies for patients with prior events. 3. Post-PE Functional Assessment: Evaluating exercise capacity and cardiopulmonary function. 4. Chronic Thromboembolic Pulmonary Hypertension: Recognition and management approaches. 5. Patient Education Topics: Symptom recognition, medication adherence, lifestyle modifications.