Pulmonary embolism nursing: Wells score, CTPA, and anticoagulation urgency

Pulmonary embolism (PE) is a blockage in one or more pulmonary arteries, most commonly caused by a blood clot that travels from the deep veins of the legs or pelvis. PE is a medical emergency and a leading cause of preventable in-hospital death. The CDC estimates that venous thromboembolism – deep vein thrombosis and PE together – affects as many as 900,000 people in the United States each year and causes 60,000 to 100,000 deaths. Sudden death is the first symptom in roughly a quarter of people who have a PE, which is why prophylaxis and early recognition carry so much weight. For nursing students, PE is high-yield: it appears across med-surg, critical care, and postoperative rotations, and it demands rapid recognition, immediate intervention, and precise pharmacological management.

This reference covers pathophysiology, the DVT-to-PE progression, Wells clinical decision rule scoring, clinical presentation, severity classification (including the 2026 AHA/ACC acute PE clinical categories), diagnostic approach, nursing interventions, anticoagulation drugs with reversal agents, patient education, and six NCLEX-style practice questions with rationales. Pair this with the ABG interpretation cheat sheet for the respiratory alkalosis and hypoxemia patterns seen in PE, and the sepsis nursing reference for the hemodynamic instability differential.

Pathophysiology

PE sits within the broader spectrum of venous thromboembolism (VTE), which encompasses both deep vein thrombosis (DVT) and pulmonary embolism. The two conditions share the same underlying pathological mechanism and are best understood together.

Virchow’s triad

Thrombus formation in the venous system follows the pattern described by Rudolf Virchow in 1856, which remains the foundational model of VTE pathophysiology. Three overlapping factors drive clot formation:

1. Venous stasis – slowed blood flow allows platelets and clotting factors to accumulate. This occurs with prolonged immobility (bedrest, long-haul flights, casting), right-sided heart failure, and obesity.
2. Hypercoagulability – an increased tendency toward clotting, driven by malignancy, pregnancy, oral contraceptive use, inherited thrombophilias (Factor V Leiden, prothrombin G20210A mutation, protein C/S deficiency), or postoperative states.
3. Endothelial injury – damage to the vessel wall from trauma, surgery, IV catheter placement, or inflammatory conditions exposes subendothelial collagen and activates the clotting cascade.

DVT progression to PE

Deep vein thrombi most often originate in the deep veins of the calf. Proximal extension into the popliteal, femoral, or iliac veins significantly increases embolic risk. When a thrombus or fragment breaks free, it travels through the right heart and lodges in the pulmonary vasculature.

The downstream effects depend on clot burden and the patient’s cardiopulmonary reserve:

• Impaired gas exchange: The embolus creates dead space – lung units that are ventilated but not perfused. This ventilation-perfusion (V/Q) mismatch causes hypoxemia. Hypoxemia drives hyperventilation, producing hypocapnia and respiratory alkalosis – the classic ABG pattern in PE.
• Increased pulmonary vascular resistance: Mechanical obstruction plus hypoxic vasoconstriction raise pulmonary arterial pressures. The right ventricle (RV) must work harder against this increased afterload.
• Right ventricular strain and failure: With a large clot burden, the RV dilates acutely. Elevated RV pressures cause interventricular septal shift (the septum bows leftward), reducing left ventricular filling and cardiac output. This produces hypotension, shock, and cardiovascular collapse if untreated.
• Reflex bronchoconstriction: Loss of local CO2 causes airway constriction in affected lung segments, worsening V/Q mismatch.

Risk factors and Wells score

Understanding risk factors helps nurses apply the Wells clinical decision rule, recognize high-risk patients before symptoms develop, and prioritize VTE prophylaxis.

Common VTE risk factors

Patient characteristics: Age > 60, obesity (BMI > 30), prior DVT or PE, inherited thrombophilia, malignancy (especially adenocarcinoma, hematological cancers), pregnancy or postpartum state, immobility, paralysis, long-distance travel (> 4 hours).

Procedural and situational: Major surgery (especially orthopedic – hip/knee replacement, hip fracture repair), central venous catheter, trauma, hospitalization, acute medical illness with bedrest.

Hormonal: Oral contraceptives (estrogen-containing), hormone replacement therapy, selective estrogen receptor modulators (tamoxifen, raloxifene).

Wells clinical decision rule for PE

The Wells score is the most widely used pre-test probability tool for PE. It stratifies patients into low, moderate, or high risk, which determines whether imaging is required or whether D-dimer testing alone is sufficient to rule out PE. Nursing students are expected to know the Wells criteria and understand how the score drives diagnostic decision-making.

These cut points (low < 2.0, moderate 2.0–6.0, high > 6.0) come from the original Wells derivation study. The same paper also created a two-tier version: a score of 4 or less is “PE unlikely” and above 4 is “PE likely.” In PE-unlikely patients with a negative D-dimer, PE was found in only 1.7–2.2% of cases. Because points are awarded in 0.5 increments, always check where a half-point score falls.

PERC rule: In patients with a clinical gestalt suggesting low PE probability (< 15%), the PERC rule can rule out PE without D-dimer testing if all 8 criteria are negative: age < 50, heart rate < 100, SpO2 ≥ 95%, no hemoptysis, no estrogen use, no prior DVT/PE, no unilateral leg swelling, no recent surgery or trauma requiring hospitalization within 4 weeks. Many emergency departments operationalize “low gestalt” as a Wells score below 2.

YEARS algorithm: An alternative to Wells used in many hospitals. It asks three questions (clinical signs of DVT, hemoptysis, PE the most likely diagnosis). With zero YEARS items, PE is excluded if D-dimer is below 1,000 ng/mL; with one or more items, the cutoff is 500 ng/mL. In the YEARS validation study, this approach avoided CTPA in 48% of patients versus 34% with the standard Wells pathway. The 2026 AHA/ACC guideline endorses YEARS for deciding who needs imaging, including during pregnancy.

Clinical presentation

PE is often called “the great masquerader” because its presentation ranges from mild dyspnea to sudden cardiac arrest. This variability makes systematic assessment critical.

Symptoms and signs

In PIOPED II, the largest prospective study of PE presentation, the most frequent findings in patients with confirmed PE were:

• Dyspnea at rest or with exertion (79% of all patients with PE; onset usually rapid, and orthopnea can occur)
• Tachypnea, respiratory rate ≥ 20/min (57%) – the most common objective sign
• Pleuritic chest pain (sharp, worse on inspiration; 47%)
• Calf or thigh swelling or pain (about 40%)
• Cough (43%), usually nonproductive
• Tachycardia > 100 bpm (26%) – present in only about a quarter, so a normal heart rate does not exclude PE
• Hemoptysis – uncommon and usually small in volume (blood-streaked or pinkish sputum)

Anxiety, restlessness, and a sense of impending doom are also common. Dyspnea can be absent even in patients with circulatory collapse, which is why a high index of suspicion matters.

Severity classification

Older nursing texts sort PE into “low-risk,” “submassive,” and “massive.” The 2026 AHA/ACC multisociety guideline, the first formal US clinical practice guideline for acute PE, replaces those labels with five AHA/ACC acute PE clinical categories. Patients are assigned by their most severe clinical, laboratory, or imaging finding and can move between categories as they improve or deteriorate.

A respiratory modifier (“R”) can be added to any category when hypoxemia, tachypnea, or escalating oxygen needs are present. Many hospitals and the 2019 ESC guideline still use the older terms, so map them like this: “massive” or ESC high-risk PE roughly equals category E, and “submassive” or ESC intermediate-risk PE spans categories C and D.

PE with hemodynamic collapse (category E, formerly “massive”) – ESC 2019 defines high-risk PE as cardiac arrest, obstructive shock, or persistent hypotension (systolic BP < 90 mmHg, or a drop of ≥ 40 mmHg from baseline, lasting longer than 15 minutes and not explained by arrhythmia, hypovolemia, or sepsis). Look for:

• Cold, clammy extremities, altered mental status, oliguria, rising lactate
• Syncope or near-syncope
• Signs of right heart strain: elevated jugular venous pressure (JVP), new right bundle branch block on ECG
• Pulseless electrical activity (PEA) cardiac arrest in extreme cases

This group is small but lethal. In the ICOPER registry, 4.5% of patients with PE presented with a systolic BP below 90 mmHg, and their 90-day mortality was 52.4%, compared with 14.7% for patients without hypotension.

Simplified PESI (sPESI)

For hemodynamically stable patients, the simplified Pulmonary Embolism Severity Index estimates 30-day mortality. One point each for: age > 80, cancer, chronic heart failure or chronic lung disease, heart rate ≥ 110 bpm, systolic BP < 100 mmHg, and arterial oxygen saturation < 90%. A score of 0 is low risk (30-day mortality about 1% in the derivation and RIETE validation cohorts, versus about 9–11% with a score of 1 or more). sPESI 0 is one of the scores that places a symptomatic patient in AHA/ACC category B.

Atypical presentations

Elderly patients may present with altered mental status or syncope as the primary complaint, with minimal respiratory symptoms. Patients with significant cardiopulmonary reserve (e.g., young, otherwise healthy adults) can appear deceptively stable with a large clot burden. Conversely, patients with pre-existing COPD or heart failure may decompensate rapidly with even a small PE. See the head-to-toe assessment reference for a systematic approach to identifying subtle changes on admission assessment.

Diagnosis

D-dimer

D-dimer is a fibrin degradation product released when a clot is broken down. It is highly sensitive for VTE (≥ 95%) but not specific – D-dimer is elevated in many conditions including infection, malignancy, pregnancy, post-surgery, and trauma. A negative D-dimer effectively rules out PE in low-to-moderate pre-test probability patients. A positive D-dimer requires imaging to confirm or exclude PE.

The nursing lab values cheat sheet includes D-dimer reference ranges. Note that many labs now use age-adjusted D-dimer cutoffs (patient age × 10 mcg/L, fibrinogen-equivalent units, in patients > 50 years) to reduce false positives in older adults. In the ADJUST-PE study, this cutoff safely ruled out PE in more patients aged 75 and older than the fixed 500 mcg/L cutoff, and the 2026 AHA/ACC guideline supports age-adjusted D-dimer in low- and intermediate-probability patients.

CT pulmonary angiography (CTPA)

CTPA is the first-line imaging test for suspected PE (invasive pulmonary angiography was the historical reference standard). It directly visualizes the pulmonary vasculature and can identify emboli down to the segmental and subsegmental level. In PIOPED II, CTPA had 83% sensitivity and 96% specificity; adding CT venography of the legs raised sensitivity to 90% (specificity 95%). A result that disagrees with the clinical probability needs further testing. Severe renal impairment and prior severe contrast reaction are relative contraindications; in these cases, a V/Q scan is the usual alternative.

Ventilation-perfusion (V/Q) scan

V/Q scanning is the alternative when CTPA is contraindicated or unavailable. Results are reported as normal, low probability, intermediate probability, or high probability. A high-probability V/Q scan with high clinical pre-test probability confirms PE. A normal V/Q scan excludes PE.

ECG findings

ECG changes in PE are common but nonspecific, and a normal ECG does not exclude PE. Key patterns to recognize:

• Sinus tachycardia – one of the most frequent findings
• S1Q3T3 pattern – S wave in lead I, Q wave in lead III, T-wave inversion in lead III – a sign of acute right heart strain; seen in only a minority of patients with PE but high-yield for NCLEX
• Right bundle branch block (RBBB) – new RBBB suggests right heart strain from elevated pulmonary pressures
• Right axis deviation
• T-wave inversions in V1–V4 – reflecting right ventricular strain

ABG findings

The classic ABG in PE shows: hypoxemia (PaO2 < 80 mmHg), hypocapnia (PaCO2 < 35 mmHg), and respiratory alkalosis (pH > 7.45). This pattern reflects V/Q mismatch driving hyperventilation as the patient attempts to compensate for hypoxemia. A normal PaO2 does not rule out PE, and a rising PaCO2 in a patient with PE can signal fatigue or circulatory collapse. See the ABG interpretation cheat sheet for the full analysis framework.

Additional labs

• Troponin I or T: Elevated with right ventricular myocardial injury (AHA/ACC categories C2 and above, the older “submassive” and “massive” groups); associated with higher short-term mortality
• BNP/NT-proBNP: Elevated with right ventricular strain; used for risk stratification
• CBC: Assess baseline hemoglobin (affects anticoagulation decisions); rule out thrombocytopenia before anticoagulation
• Coagulation panel (PT/INR, aPTT): Baseline before initiating anticoagulation; aPTT used to monitor UFH therapy

Nursing interventions

Immediate priorities: airway, breathing, circulation

1. Airway and oxygenation: ESC 2019 recommends supplemental oxygen when SpO2 is below 90%; titrate to the ordered target range. Start with nasal cannula for mild hypoxemia. For moderate-to-severe hypoxemia, the 2026 AHA/ACC guideline favors high-flow nasal cannula over standard nasal cannula. Intubation is high risk in PE with RV failure, because induction drugs and positive-pressure ventilation can drop venous return and precipitate cardiovascular collapse, so prepare for it but expect the team to try less invasive support first.
2. Position: Head of bed elevated 30–45° (semi-Fowler’s) to optimize diaphragmatic excursion and lung expansion, unless the patient is hypotensive.
3. IV access: Establish large-bore peripheral IV access (16–18 gauge) for rapid medication administration. Two peripheral IVs preferred; central access if vasopressors are anticipated.
4. Hemodynamic monitoring: Continuous cardiac monitoring (pulse oximetry, cardiac telemetry). Anticipate frequent reassessment – every 15–30 minutes in the acute phase. Report new hypotension, rising heart rate, worsening oxygen needs, falling urine output, or confusion immediately: these signal a move into a higher AHA/ACC category.
5. Fluids and vasopressors: Avoid aggressive fluid loading. An overloaded right ventricle bulges into the left ventricle and lowers cardiac output, so ESC 2019 limits fluid to a modest challenge of 500 mL or less, and only when central venous pressure is low. Norepinephrine is the usual first vasopressor for PE-related hypotension.
6. Emergency preparation: Keep the crash cart accessible. If a patient with suspected or confirmed PE arrests, ESC 2019 advises that thrombolysis should be considered during CPR; once it is given, resuscitation should continue for at least 60–90 minutes before it is stopped, because the drug needs time to work. Many hospitals activate a pulmonary embolism response team (PERT) for higher-risk PE; the 2026 AHA/ACC guideline gives PERTs a Class 1 recommendation.

Anticoagulation administration

Anticoagulation is the cornerstone of PE treatment. It does not dissolve existing clots – it prevents clot propagation and new thrombus formation, allowing the fibrinolytic system to resolve the embolus over days to weeks.

• Direct oral anticoagulants (DOACs): The 2021 CHEST guideline gives a strong recommendation for apixaban, rivaroxaban, dabigatran, or edoxaban over a vitamin K antagonist for treatment-phase anticoagulation in DVT of the leg or PE, and DOACs are the default choice for most hemodynamically stable patients. Apixaban and rivaroxaban can be started without parenteral bridging; dabigatran and edoxaban require 5–10 days of parenteral lead-in. Fixed dosing, no routine lab monitoring required. Adjusted-dose warfarin is still suggested over a DOAC in confirmed antiphospholipid syndrome. The 2026 AHA/ACC guideline also gives DOACs over vitamin K antagonists a Class 1 recommendation in patients eligible for oral anticoagulation. In pregnancy, DOACs and warfarin are avoided and LMWH is used.
• Low-molecular-weight heparin (LMWH / enoxaparin): Subcutaneous injection, weight-based dosing. The 2026 AHA/ACC guideline recommends LMWH over UFH (Class 1) when initial parenteral anticoagulation is needed, because of predictable pharmacokinetics and lower HIT risk. Monitor anti-Xa levels in severe renal impairment, extremes of weight, or pregnancy. If CrCl is below 30 mL/min, the US label reduces the treatment dose to 1 mg/kg once daily, and many clinicians switch to UFH instead.
• Unfractionated heparin (UFH): IV bolus followed by continuous infusion, titrated by weight-based or aPTT-guided protocol. Reserved for hemodynamic instability, anticipated thrombolysis or procedures, and severe renal impairment, where its short half-life and reversibility matter. Monitor aPTT every 6 hours until therapeutic (1.5–2.5× baseline), then every 24 hours. Monitor for heparin-induced thrombocytopenia (HIT) – check platelet count every 2–3 days.

Thrombolytic therapy (PE with cardiopulmonary failure)

Systemic thrombolysis with alteplase (tPA) is reserved for PE with persistent hypotension or shock (AHA/ACC category E, ESC high-risk). The FDA-labeled regimen is alteplase 100 mg IV over 2 hours. The 2026 AHA/ACC guideline calls advanced therapy (systemic thrombolysis, catheter-directed therapy, or surgical or catheter embolectomy) reasonable in category E1, says it may be considered in category D, and classifies systemic thrombolysis as harmful in categories A through C2, where bleeding risk outweighs benefit.

Absolute contraindications (ESC 2019) include any prior hemorrhagic stroke or stroke of unknown origin, ischemic stroke in the previous 6 months (the 2011 AHA statement uses 3 months), central nervous system tumor, major trauma, surgery, or head injury in the previous 3 weeks, bleeding disorder, and active bleeding. ESC relative contraindications include a transient ischemic attack in the previous 6 months, oral anticoagulant use, pregnancy or the first week postpartum, noncompressible puncture sites, traumatic resuscitation, refractory hypertension (systolic BP > 180 mmHg), advanced liver disease, infective endocarditis, and active peptic ulcer. The 2011 AHA statement also lists age over 75 as a relative contraindication. During and after the infusion, monitor for bleeding at all puncture sites, neurological changes, and signs of intracranial hemorrhage; avoid new arterial punctures and IM injections.

IVC filter

An inferior vena cava (IVC) filter is a mesh device placed percutaneously to trap emboli before they reach the lungs. The main indication is confirmed DVT/PE in a patient who cannot be anticoagulated (active bleeding, very recent major surgery). Retrievable filters are preferred, and the filter should be removed once anticoagulation can be started. Routine filter placement in patients who are already anticoagulated is not recommended; the 2026 AHA/ACC guideline classifies it as harmful.

Ongoing monitoring and safety

• Bleeding precautions: All anticoagulated patients require fall risk assessment, soft toothbrush, electric razor, no IM injections. Monitor for signs of occult bleeding: guaiac-positive stool, gross hematuria, sudden drop in hemoglobin, unexplained tachycardia or hypotension.
• DVT assessment: Inspect lower extremities every shift for asymmetric swelling, erythema, warmth, or pain (Homan’s sign is unreliable and no longer recommended for clinical assessment).
• Pain management: Pleuritic chest pain responds to positioning and analgesics. Acetaminophen is the usual first choice; avoid NSAIDs such as ibuprofen and naproxen in anticoagulated patients unless the provider specifically orders them, because they add to bleeding risk. Use opioids cautiously and reassess respiratory status after each dose.

Anticoagulation reference table

Patient education

Patients diagnosed with PE require clear, structured education before discharge, as anticoagulation adherence and recurrence prevention depend on patient understanding.

Anticoagulation duration: Most patients with PE require anticoagulation for a minimum of 3 months. Patients with an unprovoked PE (no identifiable reversible risk factor), active cancer, or recurrent VTE are often offered extended anticoagulation with no planned stop date, reviewed at least yearly against their bleeding risk. Stopping anticoagulation early significantly increases recurrence risk.

Signs of bleeding to report immediately: Unusual bruising, prolonged bleeding from cuts, red/pink/dark urine, red or tarry stools, coughing or vomiting blood, severe headache, sudden vision changes, or weakness/numbness in the face or extremities. Patients on warfarin should understand that any significant change in diet, new medication (including OTC drugs and supplements), or illness can affect INR. All patients on anticoagulants should avoid over-the-counter NSAIDs (ibuprofen, naproxen) and aspirin unless their provider approves them, and should tell every dentist and provider that they take a blood thinner.

VTE prevention behaviors: Ambulate as soon as medically cleared – even short walks every 1–2 hours break venous stasis. Stay well hydrated. Avoid prolonged sitting with legs crossed or hanging. Wear compression stockings as prescribed. During long-haul travel, walk every 1–2 hours, perform ankle pumping exercises, and stay hydrated. Avoid tight-fitting clothing around the waist or legs.

When to seek emergency care: Return to the ED immediately for sudden worsening shortness of breath, chest pain, coughing up blood, leg swelling with pain, syncope, or signs of bleeding listed above. Patients should carry a medication card identifying their anticoagulant and dose.

NCLEX-style practice questions

1. A nurse is caring for a postoperative patient on day 2 following total hip replacement. The patient suddenly reports shortness of breath and sharp chest pain that worsens with breathing. Oxygen saturation drops from 98% to 90%. Which action should the nurse take first?

A. Administer prescribed PRN analgesic for the chest pain B. Notify the provider and prepare for diagnostic imaging C. Apply supplemental oxygen and elevate the head of bed D. Obtain an ECG to evaluate for myocardial infarction

Correct answer: C. The priority action follows the ABCs – airway and breathing come first. Supplemental O2 and HOB elevation address the immediate hypoxemia and respiratory compromise. Notifying the provider and preparing for imaging (B) is the correct second action, but oxygenation takes precedence. An ECG (D) may be obtained but is secondary to stabilizing the patient.

2. A nurse is reviewing the laboratory results for a patient being evaluated for possible PE. The D-dimer result is elevated. Which statement best explains the clinical significance of this finding?

A. An elevated D-dimer confirms that the patient has a pulmonary embolism B. An elevated D-dimer indicates that systemic thrombolysis is needed C. An elevated D-dimer is sensitive but not specific – it indicates further imaging is required D. An elevated D-dimer rules out the need for anticoagulation

Correct answer: C. D-dimer is highly sensitive (detects most cases of VTE) but not specific (elevated in many conditions including infection, malignancy, recent surgery, and pregnancy). An elevated result does not confirm PE; it indicates that imaging – typically CTPA – is needed. A negative D-dimer in a low-to-moderate probability patient effectively rules out PE.

3. A nurse is administering IV unfractionated heparin to a patient with confirmed PE. The patient’s aPTT result is 45 seconds (baseline 32 seconds). How should the nurse interpret this result and what action is appropriate?

A. The aPTT is supratherapeutic – hold the heparin infusion and notify the provider B. The aPTT is subtherapeutic – follow the heparin protocol to increase the infusion rate C. The aPTT is therapeutic – continue the current infusion rate D. The aPTT is irrelevant – heparin dose is weight-based and does not require monitoring

Correct answer: B. The therapeutic aPTT range for heparin anticoagulation is 60–100 seconds, or 1.5–2.5 times baseline. At 45 seconds (about 1.4× the baseline of 32 seconds), this patient is subtherapeutic by both measures, meaning the heparin dose is insufficient to prevent clot propagation. The nurse should follow the institutional weight-based heparin protocol to increase the infusion rate and notify the provider. Supratherapeutic aPTT (> 100 seconds) would require holding or reducing the infusion.

4. A patient with PE and persistent hypotension (formerly called “massive” PE) is being evaluated for systemic thrombolysis with alteplase. Which finding in the patient’s history is a contraindication to thrombolytic therapy?

A. Age > 75 years B. Known malignancy C. Ischemic stroke 3 weeks ago D. Current use of enoxaparin

Correct answer: C. A recent ischemic stroke is an absolute contraindication to systemic thrombolysis because of the risk of hemorrhagic transformation (within 3 months in the 2011 AHA statement, within 6 months in the 2019 ESC guideline). Other absolute contraindications include any prior hemorrhagic stroke, central nervous system tumor, major trauma, surgery, or head injury within the previous 3 weeks, bleeding disorders, and active bleeding. Age > 75 (A) increases bleeding risk and is listed as a relative contraindication in the AHA statement, so it calls for careful risk-benefit analysis. Malignancy outside the central nervous system (B) is not by itself a contraindication. Transitioning from enoxaparin (D) to thrombolysis requires discontinuation but is not a contraindication.

5. A nurse is caring for a patient receiving anticoagulation therapy for PE. Which assessment finding requires the nurse to notify the provider immediately?

A. aPTT of 75 seconds on UFH infusion B. INR of 2.5 on warfarin therapy C. Platelet count of 58,000/mm³ on day 6 of heparin therapy D. Mild bruising at enoxaparin injection sites

Correct answer: C. A platelet count of 58,000/mm³ after 6 days of heparin therapy raises strong concern for heparin-induced thrombocytopenia (HIT), a life-threatening immune-mediated complication. HIT typically presents 5–10 days after heparin is started, with a platelet drop of ≥ 50% from baseline. The nurse must notify the provider immediately – heparin should be discontinued and a non-heparin anticoagulant (argatroban, fondaparinux, bivalirudin) initiated. aPTT 75 seconds (A) and INR 2.5 (B) are therapeutic. Injection site bruising (D) is expected with subcutaneous anticoagulants.

6. A nursing student is preparing to discharge a patient following treatment for DVT and PE. Which statement by the patient indicates that teaching has been effective?

A. “I should stop my blood thinner as soon as I feel back to normal” B. “I will eat more leafy green vegetables to help my blood clot normally while on warfarin” C. “I should walk short distances every one to two hours during my flight home next week” D. “I can take ibuprofen for aches because my blood thinner protects me from problems”

Correct answer: C. Getting up to walk every 1–2 hours and doing ankle pumps during long-haul travel reduces venous stasis, the first component of Virchow’s triad, and is standard VTE-prevention teaching. Stopping anticoagulation early (A) is incorrect – a minimum of 3 months is required. Increasing leafy greens (B) is incorrect for warfarin patients: vitamin K counteracts warfarin, so the goal is a consistent intake, not a sudden increase. Ibuprofen (D) is an NSAID that adds to bleeding risk on an anticoagulant and should be avoided unless the provider approves it.

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