DVT & Pulmonary Embolism — Advanced Nursing Guide

▲ Virchow's Triad — Foundation of VTE Pathophysiology

          1. Stasis
          Prolonged immobility
Long-haul flights (>4 hrs)
Bed rest / hospitalisation
Venous obstruction

        

          2. Hypercoagulability
          Malignancy
Pregnancy / puerperium
OCP / HRT
Thrombophilia
Dehydration

        

          3. Endothelial Injury
          Surgery / trauma
IV catheters
Inflammatory conditions
Sepsis

        

      DVT Pathogenesis: Thrombus forms in deep veins (usually calf/popliteal/femoral/iliac) → propagates proximally → risk of embolisation to pulmonary vasculature causing PE → RV pressure overload → haemodynamic compromise in massive PE.
    

⚠ VTE Risk Factors

Patient Factors

Age >60 — independent risk factor
Obesity — BMI >30 significantly increases risk
Previous VTE — highest single risk factor
Thrombophilia — Factor V Leiden, Prothrombin G20210A, Protein C/S deficiency, Antithrombin deficiency, antiphospholipid syndrome
Active cancer — especially pancreatic, brain, haematological
Pregnancy — all trimesters + 6 weeks post-partum
OCP / HRT — oestrogen-containing preparations

Situational / Acquired Factors

Major surgery — especially orthopaedic (THR, TKR) and abdominal
Hospitalisation / immobility >3 days
Long-haul travel >4 hours (flight, car, train)
Acute medical illness — MI, stroke, sepsis, heart failure
Dehydration
Central venous catheter / PICC
COVID-19 — significant hypercoagulable state

📈 Wells Score for DVT

Each criterion scores +1 point. Alternative diagnosis as likely or more likely = −2 points.

Active cancer (treatment ongoing, palliative, or within 6 months)+1

Paralysis, paresis, or recent plaster immobilisation of lower extremities+1

Recently bedridden >3 days OR major surgery within 12 weeks+1

Localised tenderness along distribution of deep venous system+1

Entire leg swollen+1

Calf swelling >3 cm compared to asymptomatic leg+1

Pitting oedema confined to symptomatic leg+1

Collateral superficial veins (non-varicose)+1

Previously documented DVT+1

Alternative diagnosis at least as likely as DVT−2

●

Low Probability
Score <1 — check D-dimer; if negative DVT excluded

●

Moderate Probability
Score 1–2 — check D-dimer; if positive proceed to USS

●

High Probability
Score ≥3 — proceed directly to compression USS

📈 Wells Score for PE (Two-Level)

Clinical signs & symptoms of DVT (leg swelling, pain on palpation)+3

Alternative diagnosis less likely than PE+3

Heart rate >100 bpm+1.5

Immobilisation ≥3 days OR surgery in previous 4 weeks+1.5

Previous objectively diagnosed DVT or PE+1.5

Haemoptysis+1

Malignancy (treatment within 6 months or palliative)+1

●

PE Unlikely — Score ≤4
Check D-dimer. If negative → PE excluded. If positive → CTPA.

●

PE Likely — Score >4
Proceed directly to CTPA without waiting for D-dimer.

✓ PERC Rule — Pulmonary Embolism Rule-out Criteria

Used only in patients already assessed as LOW probability for PE. If ALL 8 criteria are met (negative), PE can be excluded without D-dimer or imaging.

Age <50 years
Heart rate <100 bpm
SpO2 ≥95% on room air
No unilateral leg swelling

No haemoptysis
No recent surgery or trauma (<4 weeks)
No prior VTE
No oestrogen use (OCP/HRT/pregnancy)

💡

PERC is not used in GCC exams as a primary diagnostic tool but demonstrates understanding of pre-test probability-based clinical reasoning — know it for SCFHS/DHA MCQs.

🔍 Diagnosing DVT

Compression Ultrasound (USS)

          Gold Standard for proximal DVT
          Non-compressibility of vein = positive for DVT
Sensitivity ~95% for proximal DVT
Lower sensitivity for distal (calf) DVT (~70%)
Safe in pregnancy — no radiation
Repeat in 1 week if initial negative but high suspicion

        

D-Dimer

          High sensitivity, low specificity
          Negative result rules out DVT/PE in low-moderate probability
Positive = not diagnostic (many causes: surgery, cancer, pregnancy, infection)
Age-adjusted D-dimer: >50y → use age × 10 µg/L threshold
Do NOT use D-dimer in high-probability Wells score

        

🔍 Diagnosing PE

CTPA — CT Pulmonary Angiography

          Gold Standard — Most Widely Used
          Sensitivity and specificity >95%
Visualises filling defects in pulmonary arteries
Provides alternative diagnoses if PE absent
Use with caution: contrast allergy, renal impairment, pregnancy
Requires IV contrast — check eGFR, allergy history

        

V/Q Scan — Ventilation-Perfusion

          Alternative when CTPA contraindicated
          Preferred in: pregnancy, renal impairment, contrast allergy, young women (radiation to breast)
Results: normal / low / intermediate / high probability
Less useful in abnormal CXR or pre-existing lung disease
Lower radiation dose than CTPA in pregnancy

        

Echocardiography (ECHO)

          McConnell's sign — RV free wall hypokinesia with apical sparing (highly specific for PE)
RV dilatation — RV:LV ratio >0.9
Septal flattening / D-sign — RV pressure overloads LV
Used in massive PE for rapid bedside assessment
TOE if TTE inadequate

        

Arterial Blood Gas (ABG)

          Type 1 respiratory failure — low PaO2, normal/low PaCO2
Hypocapnia — compensatory hyperventilation increases respiratory rate
Respiratory alkalosis initially
Alveolar-arterial gradient widened
Normal ABG does NOT exclude PE

        

📊 PE Classification & Biomarkers

Classification	Haemodynamics	RV Function	Biomarkers	Management
Massive PE	SBP <90 or drop >40 mmHg >15 min	RV failure present	Troponin ↑↑, BNP ↑↑	Thrombolysis / embolectomy
Submassive PE	Haemodynamically stable	RV dysfunction on ECHO or CTPA	Troponin ↑ / BNP ↑	Anticoagulation ± thrombolysis
Low-Risk PE	Haemodynamically stable	Normal RV function	Normal biomarkers	Anticoagulation — NOAC preferred

        Troponin (I or T)
        Elevated = RV myocardial injury
Independent predictor of 30-day mortality
Used in PESI score stratification

      

        BNP / NT-proBNP
        Elevated = RV pressure overload / wall stress
Prognostic marker — not diagnostic
High BNP + troponin = very high mortality risk

      

      ECG in PE — most common finding is sinus tachycardia. Classic S1Q3T3 pattern (S wave lead I, Q wave + T-wave inversion lead III) is seen in <20% but is exam favourite. Right bundle branch block (RBBB) indicates RV strain. T-wave inversions V1–V4 common in massive PE.
    

💊 LMWH — Low Molecular Weight Heparin

Common Agents

Enoxaparin (Clexane) — 1 mg/kg BD or 1.5 mg/kg OD (therapeutic)
Dalteparin (Fragmin) — 200 units/kg OD or 100 units/kg BD
Tinzaparin (Innohep) — 175 units/kg OD

Monitoring Indications (Anti-Xa)

Obesity (BMI >40 or weight >150 kg)
Renal impairment (eGFR <30 — use UFH instead or reduce dose)
Pregnancy — dose adjustments required, anti-Xa monitoring
Extremes of body weight (<40 kg)

⚠

LMWH Contraindications / Cautions

Active major bleeding
Severe renal failure (eGFR <15) — use UFH
HIT (Heparin-Induced Thrombocytopenia) — switch to argatroban/danaparoid
Thrombocytopenia <50 × 10⁹/L

          LMWH in Pregnancy
          Drug of choice — does NOT cross placenta
Warfarin teratogenic (weeks 6–12) and increases fetal bleeding risk
NOACs contraindicated in pregnancy
Monitor anti-Xa levels 4 hours post-dose

        

💊 NOACs — Novel Oral Anticoagulants

      First-line for most non-cancer VTE — NICE, ESC, and ASH guidelines support NOACs as preferred first-line for DVT/PE in the majority of patients.
    

Factor Xa Inhibitors

          Rivaroxaban (Xarelto)
          15 mg BD with food × 3 weeks → 20 mg OD with evening meal
No bridging needed — start directly
Avoid if eGFR <15

        

          Apixaban (Eliquis)
          10 mg BD × 7 days → 5 mg BD
No bridging needed
Better renal profile — can use down to eGFR 25
Take with or without food

        

Direct Thrombin Inhibitor

          Dabigatran (Pradaxa)
          Requires 5–10 days LMWH lead-in first
150 mg BD (110 mg BD if >75 yrs or renal impairment)
Specific reversal: Idarucizumab (Praxbind)

        

💡

Cancer-Associated VTE: Rivaroxaban and apixaban now preferred over LMWH for most cancer-associated VTE (exception: GI/GU cancers with high bleeding risk → LMWH safer).

💊 Warfarin

INR Target: 2.0–3.0

Requires bridging with LMWH until INR therapeutic (>2.0) for 2 consecutive days
Loading dose: 5–10 mg day 1 (reduce in elderly, liver disease, malnutrition)
Takes 5–7 days to reach therapeutic INR
Half-life variability — multiple monitoring visits required

Major Drug Interactions

Increase INR: antibiotics (metronidazole, ciprofloxacin), amiodarone, fluconazole, cimetidine
Decrease INR: rifampicin, carbamazepine, St John's Wort, high vitamin K intake

Dietary Considerations

          Consistent vitamin K intake — not zero, but consistent
High vitamin K foods: spinach, kale, broccoli, Brussels sprouts, green tea
Cranberry juice — increases INR (inhibits CYP2C9)
Alcohol — unpredictable; generally limit
Grapefruit — minimal effect on warfarin (unlike statins)

        

          High INR Management
          INR 5–8 with no bleeding → withhold 1–2 doses
INR >8 or bleeding → Vitamin K oral/IV
Life-threatening bleed → Prothrombin Complex Concentrate (PCC) + Vitamin K IV

        

📅 Treatment Duration

Scenario	Duration	Notes
Provoked DVT/PE (surgery, trauma, transient risk)	3 months	Risk factor no longer present — lower recurrence risk
Unprovoked DVT/PE (first episode)	3–6 months then reassess	Assess recurrence risk, bleeding risk, patient preference
Recurrent unprovoked VTE	Indefinite	High recurrence risk off anticoagulation
Cancer-associated VTE	Indefinite (while cancer active)	Until cancer resolved or remission — reassess annually
Antiphospholipid syndrome	Indefinite	Warfarin preferred — NOACs show higher recurrence in CAPS
Thrombophilia (high-risk)	Individualised / indefinite	e.g. homozygous Factor V Leiden, antithrombin deficiency

💉 Advanced Interventions

Systemic Thrombolysis

          Alteplase 100 mg IV over 2 hours
          Indication: massive PE with haemodynamic instability
50 mg IV bolus in cardiac arrest
Continue CPR 60–90 minutes after thrombolysis

        

Contraindications to Thrombolysis

Active internal bleeding
Recent (<3 months) intracranial surgery/trauma/stroke
Intracranial neoplasm
Recent (<10 days) major surgery/biopsy
Uncontrolled hypertension (>185/110)
Pregnancy

Catheter-Directed Thrombolysis (CDT)

          Lower dose thrombolytic delivered directly into thrombus via catheter
Reduced systemic bleeding risk versus systemic thrombolysis
Used in: submassive PE, proximal DVT to prevent post-thrombotic syndrome
Mechanical thrombectomy devices also used (AngioJet, Aspirex)

        

Surgical Embolectomy

          Massive PE with contraindication to thrombolysis
Failed systemic thrombolysis
High surgical risk — specialist centre only
ECMO as bridge to surgery

        

⚠

MASSIVE PE — TIME-CRITICAL EMERGENCY
Haemodynamic instability: SBP <90 mmHg OR drop >40 mmHg from baseline for >15 minutes, not explained by another cause (arrhythmia, hypovolaemia, sepsis).

🚨 Immediate Assessment & Airway

Call for help immediately

Activate resuscitation team. Notify senior physician, ICU, and cardiothoracics if available.

Airway & Oxygenation

High-flow O2 via non-rebreather mask (15 L/min). Target SpO2 >90%. Intubation if unable to maintain — note: intubation can worsen haemodynamics in massive PE (loss of sympathetic drive).

IV Access & Fluid Cautiously

Two large-bore IVs. Small fluid bolus 250–500 mL if hypotensive — aggressive fluids worsen RV dilation and shift interventricular septum, further compromising LV output.

Vasopressors

Noradrenaline — first-line vasopressor for massive PE. Increases systemic vascular resistance and RV perfusion pressure. Target MAP >65 mmHg.

Bedside ECHO / CTPA

If haemodynamically stable enough — CTPA confirms diagnosis. Bedside TTE in extremis — look for RV dilatation, McConnell's sign, D-sign.

Continuous Monitoring

12-lead ECG, arterial line for continuous BP, urinary catheter for urine output, continuous SpO2, ETCO2 if intubated.

💉 Reperfusion Decision — Thrombolysis

⚠

Systemic Thrombolysis — Alteplase
Alteplase 100 mg IV over 2 hours (or 0.6 mg/kg max 50 mg over 15 min in arrest).

Indication: massive PE with haemodynamic instability where benefits outweigh bleeding risk.

          Absolute Contraindications
          Active significant bleeding
Intracranial surgery/stroke <3 months
Intracranial neoplasm
Head trauma/closed head injury <3 months

        

          Relative Contraindications
          Major surgery <10 days
Non-compressible arterial puncture
Recent internal bleeding <10 days
Pregnancy
Active peptic ulcer disease
Severe thrombocytopenia

        

💡

In cardiac arrest due to PE: Give thrombolysis if PE confirmed or strongly suspected. Continue CPR for 60–90 minutes after thrombolysis before considering cessation. This is a key exam point.

💉 Advanced Rescue Therapies

          Surgical Embolectomy
          Failed or contraindicated thrombolysis
Cardiac surgery centre required
Cardiopulmonary bypass
High mortality but only option in some cases

        

          ECMO
          VA-ECMO as bridge to embolectomy or thrombolysis
Supports cardiac output while treatment arranged
Specialist centres in GCC (King Faisal, Cleveland Clinic Abu Dhabi)

        

          IVC Filter
          Temporary — inserted when anticoagulation contraindicated but PE risk high
Does NOT treat existing PE — prevents further embolism
Must be removed once anticoagulation possible
Not recommended routinely

        

💡

Catheter-Directed Therapy in Submassive PE: Catheter-directed thrombolysis or ultrasound-assisted CDT (EKOS system) may be used for submassive PE (haemodynamically stable + RV dysfunction) — lower bleeding risk than systemic thrombolysis.

🔒 VTE Prophylaxis — Risk Assessment

Padua Prediction Score (Medical Patients)

Active cancer+3

Previous VTE+3

Reduced mobility ≥3 days+3

Known thrombophilic condition+3

Recent (<1 month) trauma/surgery+2

Age ≥70+1

Heart/respiratory failure+1

MI or ischaemic stroke+1

Obesity (BMI >30)+1

Ongoing hormonal therapy+1

●

Score ≥4 = High risk → LMWH prophylaxis recommended

Mechanical Prophylaxis

          TED Stockings (Thrombo-Embolic Deterrent) — graduated compression, knee or thigh length
Intermittent Pneumatic Compression (IPC) — sequential compression devices on calves — more effective than stockings alone
Used when pharmacological prophylaxis contraindicated (active bleeding, recent surgery on CNS)
Combined mechanical + pharmacological = most effective

        

Surgical Prophylaxis Timing (Caprini Score)

          Start LMWH: 12 hrs pre-op (low bleeding risk) or 12 hrs post-op
High VTE risk surgery (THR/TKR): minimum 28 days extended prophylaxis
Orthopaedic surgery: rivaroxaban or apixaban now licensed for surgical VTE prophylaxis

        

👁 Nursing Monitoring on Anticoagulation

Bleeding Surveillance

          IV sites / venepuncture sites — prolonged oozing, haematoma
Haematuria — check urine colour each void
Rectal bleeding / melaena — stool colour and consistency
Intracranial — new headache, confusion, focal neurology, GCS drop
Retroperitoneal — flank pain, unexplained hypotension
Haemoptysis — cough with blood
Epistaxis / gum bleeding — minor but indicator

        

LMWH Injection Sites

          Inspect for bruising, induration, lipodystrophy
Rotate sites: left/right abdomen alternating
Do NOT rub after injection — increases bruising
Pinch skin — inject at 90° into subcutaneous tissue
Withdraw needle before releasing skin

        

HIT Monitoring

          Check platelet count days 4–14 if on heparin (UFH or LMWH)
HIT: platelet drop >50% from baseline = suspect
4T score to assess probability
Stop heparin immediately if HIT confirmed — switch to argatroban

        

📚 Patient Education

LMWH Self-Injection (Home)

          Demonstrate & return demonstration before discharge
Site rotation chart — abdomen preferred
Sharps disposal container
Missed dose: take as soon as remembered if >12 hrs remaining to next dose
Store in refrigerator (not freezer)
Do not aspirate before injection

        

NOAC Education

          Rivaroxaban — take with largest meal of day
Apixaban — with or without food
No routine blood monitoring required
Do NOT take NSAIDs / aspirin unless prescribed
Missed dose: take same day if remembered; do NOT double-dose next day
Avoid St John's Wort and herbal anticoagulants

        

When to Seek Emergency Help

⚠

Unusual or uncontrolled bleeding anywhere
Coughing or vomiting blood
Severe headache, vision changes, confusion
Black tarry stools or red blood in toilet
Sudden chest pain or shortness of breath

Travel Advice

          Stay hydrated — avoid alcohol on flights
Leg exercises every 1–2 hours (calf pumps, ankle circles)
Walk aisle every 2 hours on long flights
Wear class 1–2 compression stockings
Aisle seat preferred
Consider LMWH for very high risk travellers

        

🔗 Post-Thrombotic Syndrome (PTS) Prevention

          Graduated Compression Stockings
          Below-knee class II (23–32 mmHg) for 2 years after proximal DVT
Reduces PTS symptoms: leg pain, swelling, varicosities, skin changes, ulceration
SOX trial questioned benefit — evidence mixed, but practical symptomatic benefit for most patients
Apply in morning before standing
Replace every 3–6 months

        

          PTS Presentation
          Occurs in 20–50% after proximal DVT
Aching, heaviness, swelling — worse after standing
Skin changes: pigmentation, lipodermatosclerosis
Venous ulceration (severe cases)
Chronic pain significantly affects quality of life

        

💉 Anticoagulation Reversal Agents

Anticoagulant	Reversal Agent	Mechanism	Onset	Notes
UFH (Heparin IV)	Protamine Sulfate	Binds heparin directly	Minutes	1 mg per 100 units UFH; risk of hypotension/anaphylaxis
LMWH	Protamine Sulfate (partial)	Partially reverses anti-IIa effect	Minutes	Reverses ~60% of anti-Xa activity; not fully effective
Warfarin	Vitamin K + PCC	Replenishes clotting factors	PCC: minutes; Vit K: hours	PCC for life-threatening bleed; Vit K alone for non-urgent reversal
Rivaroxaban / Apixaban	Andexanet Alfa (Ondexxya)	Decoy Xa molecule — binds and sequesters factor Xa inhibitors	Minutes	Very expensive; limited availability in some GCC centres
Dabigatran	Idarucizumab (Praxbind)	Monoclonal antibody — binds dabigatran	Minutes	5g IV; complete reversal in most patients
All NOACs	PCC (4-factor) — off-label	Replaces clotting factors	Minutes	Used when specific reversal unavailable

🌎 GCC-Specific VTE Considerations

High-Risk Populations in GCC

          Long-haul flight workers — significant expat population arriving from South/Southeast Asia, Africa; high-risk for economy class syndrome
Hajj pilgrims — immobility in crowd crush, extreme heat causing dehydration, very high BMI population, physically exhausted elderly pilgrims; high VTE risk in Mina/Arafat
Post-surgical VTE — orthopaedic load in GCC (bariatric surgery, knee/hip replacement increasingly common)
High BMI population — GCC has among world's highest obesity rates → multiple VTE risk factors in single patient

        

Thrombophilia in Arab Populations

          Factor V Leiden — relatively prevalent in Middle Eastern populations; screen young Arab patients with unprovoked VTE
Prothrombin G20210A mutation — increased prevalence in Arab/Mediterranean populations
MTHFR mutation — common but clinical significance debated
Thrombophilia screening common practice in GCC oncology and haematology units for young patients
Consanguinity in Arab families increases homozygous mutation risk

        

NOACs Availability & Cost

          Rivaroxaban and apixaban widely available in Saudi Arabia, UAE, Kuwait, Qatar, Bahrain, Oman
Cost can be significant without insurance coverage — affects adherence in lower-income expat workers
LMWH still widely used for cancer-associated VTE and pregnancy
DHA and MOH formularies vary — know local drug availability

        

DHA/DOH VTE Bundle Compliance

          VTE risk assessment mandatory on all hospital admissions in Dubai (DHA policy)
Padua and Caprini scores used in electronic health records
VTE prophylaxis bundle: risk assess → prescribe LMWH + mechanical → document reason if omitted
Quality indicators tracked — compliance monitored via HAAD/DHA audits
Joint Commission International (JCI) accreditation in UAE hospitals requires VTE prevention protocol

        

🌞 Ramadan Fasting & Anticoagulation

💡

A unique clinical challenge in the GCC — approximately 1 billion Muslims fast annually. Patients on anticoagulation require careful management during the 29–30 day fast.

NOACs During Ramadan

          Rivaroxaban (20 mg OD): take with Iftar (breaking fast meal at sunset) — food required for absorption
Apixaban (5 mg BD): split doses between Iftar and Suhoor (pre-dawn meal) — flexible as food not required
Dabigatran (150 mg BD): take with Iftar and Suhoor
Counsel patients not to skip doses — DVT/PE breakthrough risk
Dehydration during fasting hours increases VTE risk — increased water intake at Iftar/Suhoor

        

Warfarin During Ramadan

          Significant INR instability during Ramadan
Dietary changes: increased vitamin K intake from traditional Ramadan meals (lentil soup, leafy vegetables, dates)
Changed meal timing alters drug absorption patterns
More frequent INR monitoring recommended during Ramadan
Consider switching stable patients to NOACs before Ramadan
Advise consistent meal composition at Iftar/Suhoor

        

📚 DHA / DOH / SCFHS Exam Preparation

High-Yield Exam Topics

          Wells PE score — know each criterion and points exactly; PE unlikely ≤4, PE likely >4
CTPA — gold standard for PE diagnosis; know when to use V/Q (pregnancy, renal failure, contrast allergy)
Massive PE management — alteplase dose 100 mg over 2 hours; CPR 60–90 min post-thrombolysis in arrest
LMWH dosing — enoxaparin 1 mg/kg BD; anti-Xa monitoring in obesity/renal/pregnancy
Duration — provoked 3 months; unprovoked 3–6 months; cancer indefinite
Reversal agents — andexanet alfa for Xa inhibitors; idarucizumab for dabigatran

        

Common MCQ Traps

⚠

D-dimer — used only in LOW/MODERATE probability; do NOT order if high Wells score
Warfarin in pregnancy — CONTRAINDICATED; LMWH is the answer
NOACs in pregnancy — CONTRAINDICATED; LMWH is the answer
Antiphospholipid syndrome — warfarin preferred over NOACs
PERC rule — only applicable to LOW pre-test probability patients
McConnell's sign — RV free wall hypokinesia with apical sparing → specific for massive PE
S1Q3T3 on ECG — classic finding taught, but sinus tachycardia is actually most common

Scenario	Correct Answer	Common Wrong Answer
Pregnant woman, DVT confirmed	LMWH throughout pregnancy + 6 weeks postpartum	Warfarin or rivaroxaban
Wells PE score 3 — what next?	CTPA (score >4 = PE likely → direct CTPA; score 3 is "PE unlikely" → D-dimer first)	Immediate CTPA
Massive PE with cardiac arrest	Alteplase 50 mg IV bolus + CPR 60–90 minutes	Stop CPR, give thrombolysis, restart
Dabigatran — life-threatening bleed	Idarucizumab 5 g IV	Andexanet alfa (wrong drug class)
Cancer patient with DVT — anticoagulant choice	Rivaroxaban or apixaban (unless high GI/GU bleeding risk → LMWH)	Warfarin
LMWH prophylaxis contraindicated — what to use?	Mechanical: IPC + TED stockings	No prophylaxis

🆕 Interactive Wells PE Score Calculator

Select all clinical features present. Score updates automatically.

Clinical signs & symptoms of DVT (leg swelling + pain on palpation of deep veins) +3 pts

Alternative diagnosis is less likely than PE +3 pts

Heart rate >100 bpm +1.5 pts

Immobilisation ≥3 days OR surgery in previous 4 weeks +1.5 pts

Previous objectively diagnosed DVT or PE +1.5 pts

Haemoptysis (coughing blood) +1 pt

Malignancy (treatment within 6 months or palliative) +1 pt

No criteria selected

📈

Probability

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🧬

D-Dimer

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Imaging

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