PULMONARY EMBOLISM

Dr.Partha DasMEM,PGY2Fortis Hospital, Kolkata08/04/2016

STATISTICS (INDIAN SCENARIO)• Overall, the annual incidence of PE

ranges between 23 and 69 cases per 100,000 population

•  Responsible for up to 15% of all in-hospital deaths

• Accounts for 20 to 30% of deaths a/w pregnancy & delivery

• Average case fatality rate within 2 weeks of Δ of ~ 11 %

• Roughly accounting for at least 100,000 deaths each year

Ref : indianheartjournal.com/ihj09/sep_oct_09/467-469.html

DEFINITION

• Refers to the obstruction of the pulmonary artery or one of its branches by a thrombus (or thrombi) that originates somewhere in the venous system or in the right side of the heart

PATHOPHYSIOLOGY• Embolization• Impaired gaseous exchange• Increased pulmonary vascular resistance• Increased airway resistance• Decreased pulmonary compliance

Contd…As pulmonary vascular resistance↑, RV wall tension ↑ & causes further RV dilation & dysfunction

↓↑ RV wall tension also compresses the RCA

↓↓ subendocardial perfusion & limits myocardial oxygen supply

↓Provokes MI → eventually circulatory collapse & death may ensue

Ref : Harrison’s Principles of Internal Medicine, 18th Ed

PREDISPOSING FACTORS• Malignancy• Prolonged bed rest• Long-haul air travel• Obesity• COPD• Systemic arterial HTN• Smoking• OCPs• Pregnancy• Surgery & trauma• Post menopausal hormone replacement• Thrombophilia, AF

HEREDITARY FACTORS• Antithrombin III deficiency• Protein C deficiency• Protein S deficiency• Factor V Leiden • Plasminogen abnormality• Fibrinogen abnormality• Resistance to activated Protein C

VIRCHOW’S TRIAD

CLINICAL FEATURES• Dyspnoea (m/c)• Pleuritic chest pain (sudden & sharp)• Substernal chest pain• Cough• Fever• Hemoptysis• Syncope• Unilateral leg pain (signs of DVT)• Diaphoresis• Tachycardia, Tachypnoea• Hypoxemia (paO2 < 8ommHg)• S3 or S4 gallop/cardiac murmur

Well’s Score For PE• HR > 100 1.5• Hemoptysis 1• H/o previous TE 1.5• Active malignancy 1• Signs of DVT 3

Risk for PE>6 = High risk2-6 = Moderate risk<2 = Low risk

PE Severity Index (PESI)Predictors Points

• Age +1 per year

• Male sex +10• Heart Failure +10• Chronic Lung disease +10• Art. O2 sat. <90% +20• Pulse >110bpm +20• RR>30/min +20• T˚<36˚C/96.8˚F +20• Cancer +30• SBP<100mmHg +30• Altered mentation +60

Contd…

Score Risk Class

• <65 I• 66-85 II• 86-105 III• 106-125 IV• >125 V

*Low prognostic risk is defined as ≤ 85 points

PE R/O Criteria (PERC)

• Age < 50 years• HR < 100 bpm• SpO2 >95% in R/A• No Hemoptysis• No exogenous Estrogen use• No previous TE• No trauma/Surgery requiring

hospitalization (in 4 weeks)• No U/L leg swelling

DIAGNOSTIC FINDINGS

Chest X Ray • Radiographic signs include:-• Fleishner sign: enlarged pulmonary artery

(20%)• Hampton hump: peripheral wedge of

airspace opacity and implies lung infarction (20%)

• Westermark's sign: regional oligaemia and highest positive predictive value (10%)

• Pleural effusion (35%)• Knuckle sign  Ref : http://radiopaedia.org/articles/pulmonary-embolism

Contd…ECG

• Sinus tachycardia – m/c abnormality• Complete or incomplete RBBB – a/w ↑

mortality• RV strain pattern – T wave ↓ in the right

precordial leads (V1-4) ± the inferior leads• Right axis deviation• Right atrial enlargement (P pulmonale)

– peaked P wave in lead II > 2.5 mm in height

• Atrial Tachyarrhythmias – AF, Flutter• Non specific ST-segment & T wave cha

nges

Contd…CT Pulmonary Angiography

(CTPA)• filling defects within the pulmonary

vasculature with acute pulmonary emboli• When observed in the axial plane this has

been described as the polo mint sign

Contd…

Other Investigations :-• ECHO - It helps to detect RV

enlargement & RWMA a/w PTE(McConnell’s sign - hypokinesia of RV free wall with normal motion of RV apex is best known indirect sign of PE)

• ABG - ↓ PaO2

• D- Dimer assay• NT Pro BNP• V/Q Scan• Venous USG & Impedence

Plethysmography• Contrast enhanced Helical CT Lung

Diagnostic Approach

Management• Provide O2 by cannula/mask/ventilator –

as indicated• Elevate head-end of bed• Elevate lower extremities if DVT is

present• Morphine to manage pain & anxiety

(avoid in case of severe Hypotension)• Inj. Heparin 10,000 U i/v bolus followed

by 5000 U i/v 6 hourly charged in 200 ml N/S

• LMWH (Enoxaparin 1mg/kg BD s/c)• Dopamine or Dobutamine infusion to treat

hypotension & shock

Different LMWH in use

Name Treatment DoseEnoxaparin

1 mg/kg twice daily (approved as an inpatient or outpatient dose), or 1.5 mg/kg once daily (inpatient dose only)

Dalteparin100 units/kg twice daily, or 200 units/kg once daily

Tinzaparin175 units/kg once daily

Pulmonary Embolectomy

• Emergency surgical removal of emboli which are blocking blood circulation & causing necrosis

Vena Cava Filter

• Type of vascular filter, a medical device that is implanted into the inferior vena cava to presumably prevent life-threatening pulmonary emboli

Prevention• Leg exercises (Dorsiflexion of feet)• Frequent position changes• Ambulation• Intermittent pneumatic leg

compression devices• Anti embolism stockings• Tab.Warfarin 5mg BD x 3-4 weeks &

then can be tapered to keep INR @ 2.5-3

REFERENCES• Tintinalli’s Emergency Medicine e-Book

6th Edition• Harrison’s Principles of Internal Medicine

18th Edition• European Heart Journal, 2014• Kapoor VK. Venous thromboembolism in

India. The National Medical Journal. 2010;23(4):193-95.

• European Heart Journal Advance Access published August 29, 2014

• radiopaedia.org/articles/pulmonary-embolism