dr viviana elliott consultant physician acute medicine pulmonary embolism
TRANSCRIPT
Objectives
• To be able to understand pathophysiology
• To be able to understand importance of early diagnosis
• To be able to recognise signs and symptoms
• To be able to request investigations appropriately
• To be able to treat pulmonary embolism
• To be able to investigate and treat PE in special situations ( Massive PE, pregnancy and cancer)
Pathophysiology
Venous thrombi originatepredominantly in venous valve pockets and at other sites of
presumed venous stasis
Virchow’s Triad
Case 1
• Female 40 years old
• Chest tightness and shortness of breath for two days
• Past Medical History: Crohn’s disease
• Presents to ED RR 35x’, BP 80/40 mmHg, Sat: 80%
• Transferred to resus with suspected PE
• Thrombolised
• Arrested and died within 20’ of arrival
• Post mortem: massive PE
Incidence of Pulmonary embolism• 60-70 cases/100.000
• 50% develop PE while in hospital or in long term care
• 25% idiopathic cases
• 25% have recognised risk factors
Reduced mobility
• Hospitals stay !!!!!!• Fractures (Hip-Knee- Ankle)• Major surgery • Trauma • Spinal cord injury• Immobilizer or cast
Acute medical conditions
Hospital admission for acute illnessPregnancy Postpartum periodPolycythemia veraOral contraceptives Hormone-replacement Cancer Chemotherapy Advanced age Obesity Central venous catheterization
Hereditary Clue in the history!!!
Factor V LeidenAntithrombin deficiencyProtein C deficiencyProtein S deficiencyActivated protein C resistance without factor V LeidenProthrombin gene mutationDysfibrinogenemiaPlasminogen deficiency
PIOPED- symptoms and signs
Symptoms Dyspnoea (SOB) 73%
Pleuritic pain 66%
Cough 37%
Haemoptisis 13%
Signs Tachypnoea70%
Crackles 51%
Tachycardia 30%
Syndromes Pain & haemoptisis 65%
CVS collapse 8%
CXR findings in PE• Normal
• Laminar atelectasia
• Wedge infarct
• Pleural effusion
• Infiltrates
• Prominent pulmonary arteries (Fleishner sign)
• Oligemia ( Westermark’s sign)
• Pleural based opacity (Hampton’s hump sign)
Case• Female 82
• Admitted to ED
• Carers rung the ambulance as patient was short of breath and collapsed at home
• Ambulance crew
HR: 115 x’ RR: 32 x’ Sat: 82% on air
• PMH:
Discharged from hospital the week before admission with haemorrhagic cystitis
Recurrent UTIs :E. Coli ESBL (Extended Spectrum Beta Lactamase )
USS BOTH LEGS AND ABDOMEN• Right leg:
occlusive DVT is seen in right femoral vein extending to adductor canal region. The right popliteal vein was patent. Left leg: Short segment of non-occlusive DVT in the common femoral vein. The rest of the SFV and popliteal vein remain patent. US Pelvis (Transabdominal) : Urinary bladder empty with catheter in situ. No pelvic free fluid. uterus and ovaries not seen. No pelvic masses.
More informatio:
• 79% of patients presenting with PE have DVT in their legs!!!
• 50% of patients with DVT will have a PE
Preliminary Testing• Blood tests:
Mildly raised WBC and CRP
• ECG:
tachycardia
atrial fibrilation
manifestations of acute cor pulmonale
S1, Q3, T3 pattern,
right bundle-branch block
P-wave pulmonale
right axis deviation
Patient to ED with suspected PE
History + Risk factors + CxR and ECG
Potential PE identified &Well’s Score
Low probability(Well’s Score <4) High probability
abnormal X ray pre-existing cardio respiratory disease
High probabilityNormal chest X ray
D Dimer
If –ve, discharge
CTPA undertakenwithin 24 hours
UHCW:Q/VQ scan (weekdays)
CTPA (weekends)
Management plan
Treatment• LMWH 1.5 mg/kg
• Warfarin until INR between 2-3
• When INR 2-3 continue LMWH 5 more days– INR is often deceptive in the first days
factor VII has a half-life of 6 to 8 hours, the initial increase in
INR following the start of warfarin therapy reflects factor
VII depletion rather than attainment of true systemic anticoagulation.
- Factor II and X depletion takes 4 to 5 days
• Duration 6 months at UHCW
( 3 months same mortality less bleeding risk)
Massive PE• High suspicious
50% EMD (electromechanical dissociation)
Asystolic
very few survive whatever you do
• Diagnosis
ECHODiagnostic abnormal in 80%dilated RV & PAregional RV wall abnormalityintracardiac clot
CTPA (if stable)
Treatment for massive PE Thrombolysis
• What to give?
• 50 mg bolus of Alteplase
• If cardiac arrest CPR 60’
• Alternative to thrombolisis:
Embolectomy / right heart catheter clot fragmentation
can be considered if experience and facilities available
Suspected PE in pregnancy
• History with risk factors
• D Dimer? : NO THANK YOU!!!
• ECG
• Further investigation: gold standard USS both legs
Further investigation
Procedure Effective radiation dose Natural background radiation
CT-Chest 7 mSv 2 years
Chest X ray 0.1 mSv 0.1 to 0.9 mGy
10 days
Pregnancy and PEFetal Radiation
V/Q 0.11-0.22 mGy (milligray)
CTPA 0.01-0.06 mGy
Incidence of malignancy 1:16,000 per mGy
IV iodinated contrast : neonatal hypotyroidism
Mother
CTPA 35 mGy per breast
½ perfusion V/Q 0.25 mGy per breast
Life time risk of breast cancer reported with one dose of 10 mGy
PE in pregnancy- imaging at UHCW
• CxR to exclude other causes
• Half dose perfusion V/Q
• CTPA only in cardio respiratory disease or abnormal CxR
Treatment of PE in pregnancy
• Treatment:
Enoxaparine 1 mg BD
Warfarine is teratogenic
UFH should be given as delivery approaches
? Stop 4-6 hs pre – delivery
Continue anticoagulation 6 weeks post delivery or 3 months post event
Cancer Screening in PE
• 7 -12 % of idiopatic VTE presents with cancer in next 6 – 12 months
• Should we hunt for it?
• Most will be picked up by:
clinical history examination CxR
• Further tests are not warranted
1 year survival of occult cancer is 12 %
Most have metastasis at the diagnosis
VTE in cancer patients is poor prognostic factor
• Treatment LMWH
Messages to take home• PE is a medical emergency
• High level of suspicion
• Think PE in all patients recently discharged from hospital
• Request D Dimer only in low probability PEs
• Remember to continue Enoxaparine 5 more days after the INR is in range (2-3)
• Thrombophylia screen after the treatment has been completed
• Best treatment: PREVENTION!!!
References• British Thoracic Society guidelines for the
management of suspected acute pulmonary embolism. Thorax 2003;58:470–484
• Victor F. Tapson, M.D Acute Pulmonary Embolism NEJM 358;10, 2008
• Why shouldn’t we use Warfarin alone to treat acute venous thrombosis? Cleveland Clinic Journal of medicine, volume 69, number 7 July 2002
• Investigating suspected pulmonary embolism in pregnancy. BMJ 2007:334:418-9