PE

1. PULMONARY EMBOLISM
PRESENTER : Novath Ngowi, M.D
FACILITATORS:
Dr. Hilal
Dr. Moses

2. OUTLINE
1. Objectives
2. Introduction
3. Pathophysiology
4. Clinical picture
5. Diagnosis
6. Investigation
7. Treatment
8. Prophylaxis

3. Introduction
 Is the occlusion of one or more vessels in the
pulmonary arterial tree by matter from a
source extrinsic to the lung
 Almost invariably acute
 May be chronic
 Common and potentially fatal due to V/Q
mismatch

4. Intro…
 One of the most common cause of preventable
death and the second most common cause for
increased length of hospitalization
 Diagnosis missed in about 70% of the cases
 Severity depends on size and cardiopulmonary
reserve

5. Epidemiology
 Prevalence: 6.2 - 50 per 100,000
population/yr
 Increases with age > 70
 Highest in US,
 Develops in up to 20% of patients 90 days
post-surgery
 High case fatality: 15 - 30%

6. Epidemiology…
 In Tanzania, devoid of researches on PE
 2016 – MNH, DVT incidence = 24.7%
 2017 – MOI, DVT incidence post hip fracture
repair = 6.1%

7. Etiology – VTE
• Immobility or paralysis
• Heart failure
• Venous insufficiency or varicose veins
• Venous obstruction from tumor, obesity or pregnancy
• Surgery
• Trauma
• Indwelling
catheter
• Atherosclerosis
• Heart valve
disease or
replacement
• Acute phase postop
• Cancer
• Thrombophilia
• Estrogen therapy
• Pregnancy and
postpartum period
• Inflammatory bowel disease

8. Pathophysiology

9. Pathophysiology…
 Depend upon:
1. Extent of occlusion
2. Patient’s pre-existing cardiopulmonary
condition
3. Chemical vasoconstriction effect
4. Reflex vasoconstriction

10. Clinical Picture
 Variable & Non Specific:
 Tachypnea
 Tachycardia
 Hemoptysis – lung infarction
 Pulmonary hypertension
 ⬆︎^LFT, ˆP2, RVH⬆︎⬆︎

11. Clinical Picture…
 Other atypical symptoms:
Seizures
Syncope
Abdominal pain
Delirium (elderly patients)

12. Diagnosis
 Clinically challenging
 The Well’s score (Well’s Criteria) – to predict
probability
Use complicated by multiple versions being
available

13. Well’s Score
Clinical Characteristic Score
Previous PE or deep vein thrombosis + 1.5
HR >100 beats per minute + 1.5
Recent surgery or immobilization (within the last 30 d) + 1.5
Clinical signs of DVT + 3
Alternative diagnosis less likely than pulmonary embolism + 3
Hemoptysis + 1
Malignancy (treated within the last 6 mo) + 1
Clinical Probability of Pulmonary Embolism Score
Low 0-1
Intermediate 2-6
High ≥7

14. Well’s score…
 Traditional interpretation (Three tier)
 Score > 6.0 – High (Probability 59%)
 Score 2.0 to 6.0 – Moderate (Probability 29)
 Score < 2.0 – Low (Probability 15% )

15. Investigations
1. CT angiogram
 Specific
 Good for large, centrally located thrombi
 GFR
2. V/Q Scan
 Relatively specific
 Better at peripheral thrombi – chronic PE
 Pneumonia may obscure

16. Case courtesy of Dr Stefan Ludwig, Radiopaedia.org, rID: 13894

17. Westgate EJ, FitzGerald GA - Pulmonary Embolism in a Woman Taking Oral Contraceptives and Valdecoxib. PLoS
MedicineVol. 2, No. 7, e197. doi:10.1371/journal.pmed.0020197

18. Investigations..
3. US of BLE
 Specific
 Positive surrogate to PE
 Negative test doesn’t r/o PE
4. D- dimer
 Not specific
 Positive rules in PE

19. Investigations...
5. Plain CXR
 Not specific
 Westermark’s sign - ↓ peripheral pulmonary Vasculature
 Palla’s sign – Enlarged Rt descending Pulmonary Artery
6. ECHO
 Not specific – Apex may/not be moving
7. EKG
 Not specific
 SIQIIITIII – Rt heart strain

20. The most common ECG finding in the setting of a pulmonary embolism is sinus
tachycardia. However, the “S1Q3T3” pattern of acute cor pulmonale is classic; this
is termed the McGinn-White Sign. A large S wave in lead I, a Q wave in lead III and
an inverted T wave in lead III together indicate acute right heart strain

21. Chest radiograph (posterior–anterior view) showing a lateral wedge-shaped opacity (white
arrow) in the right lower zone (Hampton’s hump), a focal area of oligemia (space between white
arrow heads) in the right lower zone (Westermark’s sign) and a prominent right descending
pulmonary artery (black arrow) (Palla’s sign).
Hameed Aboobackar Shahul et al. BMJ Case Rep
2019;12:e231693

22. Other investigations…
 ABG: ↑pH |↓PCO2 | ↓O2
 PT, APTT, TT
 FBP
 ESR

25. Management
 For convenience, may be grouped into:
a) Asymptomatic pulmonary embolism
b) Symptomatic pulmonary embolism
c) Sub-massive pulmonary embolism
d) Massive pulmonary embolism

26. Category Admission? SX Anatomy Vitals
changes
Rx
Asymptomatic
PE
NO Ø Ø Ø LMWH  Coumadin
Symptomatic PE General Ward ⊕ Ø Ø LMWH  Coumadin
Sub-massive PE ICU ⊕ ⊕
Trop
BNP
ECHO
Ø Heparin infusion
Massive PE ICU ⊕ ⊕
Trop
BNP
ECHO
⊕ tPA

27. Medical management
1. Fibrinolytic
 Indicated for:
Hemodynamically unstable Pts
Pts with right heart strain
Pts who are expected to have multiple
recurrences of PE

28. Medical management...
 Alteplase (t-PA)
 Fibrin specific,
 Recombinant human tissue-type plasminogen
activator (t-PA); produces local fibrinolysis.
Promotes thrombolysis by converting
plasminogen to plasmin; plasmin degrades
fibrin and fibrinogen
 Metabolized by liver,Half life of 4 min
 Extremely expensive

29. Medical management...
 Urokinase
 Half life 15 min
 Metabolized by the liver
 Not fibrin specific thus produce systemic
lytic effect

30. Medical management...
 Streptokinase
 Half life of 80 min
 It forms a complex with plasminogen, which
then converts to the proteolytic enzyme plasmin.
This process results in a cascade that ultimately
leads to the lysis of fibrin clots. Streptokinase
causes a systemic thrombolytic state that usually
resolves within 48 hours of administration
 Administered by continuous infusion for 6 hrs
OD for 2-3 days then heparin infusions

31. Medical management...
 Complications of fibrinolytics
 Distal embolism of partially lysed clot
 Allergic reaction and rarely
anaphylaxis
 Hemorrhage – Rare

32. Medical management...
2. Anticoagulants
 Heparin
 Augments antithrombin III which prevent
conversion of fibrinogen to fibrin
 Early anticoagulation – stops clot extension and
consequent embolization of new thrombi

33. Medical management...
 Heparinasation complications
 Intracranial hemorrhage (4-9%)
 Heparin induced Thrombocytopenia (2-5%)
 Effect of Heparin can be reversed with
Protamine sulphate

34. Medical management...
 Warfarin
 For maintenance therapy (1-3 days post
heparinization)
 Interferes with synthesis of Vit K dependent clotting
factors (II, VII, IX, X) + Protein C & S
 Maintenance dose is 5mg/day
 Duration is 8-12wks for normal pts and for high risk
patients 3-6 months

35. Percutaneous Treatment
 Recanalizes the pulmonary trunk or arteries
 When thrombolysis is contraindicated or has
failed
 Access through Jugular or Femoral venotomy
 Categories:
 Aspiration thrombectomy
 Thrombus fragmentation
 Rheolytic thrombectomy

36. Percutaneous Treatment…
 IVC filter placement
 When anticoagulation therapy is contraindicated
 Access through Jugular or Femoral vein
 Complications:
 More DVTs
 Fracturing
 Migration
 Perforation

37. Surgical management
1. Acute Pulmonary Embolectomy
 Indications:
 Hemodynamically unstable pt deemed unlikely
to survive
 Definitive dx of PE the main or lobar
pulmonary arteries
 Contraindications to thrombolytic or
anticoagulation therapy
 Large clot within RA or RV

38. Acute Pulmonary Embolectomy…
 Trendelenburg (1908) first described it thru
transthoracic approach – no survivors
 Sharp (1962) – first successful using
cardiopulmonary bypass
 Median sternotomy incision
 Cardiopulmonary bypass is instituted

39. Acute Pulmonary Embolectomy…
 Occluding tapes are placed around SVC & IVC
 Two polypropylene sutures are placed in the mid–
pulmonary artery for traction
 A longitudinal incision between these sutures in
the main pulmonary artery trunk 1 to 2 cm distal
to the valve
 Can be extended directly into the left
pulmonary artery

40. Acute Pulmonary Embolectomy…
• The emboli are extracted using forceps, suction,
and balloon catheters
• Pleural spaces can be entered
• Lungs manually compressed to dislodge small
distally lodged clots, which can then be suctioned
out
• Closure 6-0 polypropylene suture

41. Surgical management…
2. Extracorporeal life support (ELS)
 For massive PE or imminent cardiac arrest
 Can be implemented within 15 to 30 minutes &
maintained for a period up to several weeks
 IV heparin bolus of 1 mg/kg
 Percutaneous or surgical cut-down of the femoral
artery and femoral or internal jugular veins

42. Surgical management…
2. Extracorporeal life support (ELS)
 The tip of the venous catheter is advanced into the
right atrium to obtain a flow rate of 2.5-4.0 liters/min
 An electromagnetic flow- meter is placed on the
arterial line
 Thrombolytic drugs may be instilled directly into the
pulmonary artery via a Swan-Ganz catheter to aid in
clot lysis
 Bridge an unstable patient to surgical embolectomy

44. Management...
 For Chronic PE:
 Long-term anticoagulation therapy
 Open pulmonary thromboendarterectomy
 Heart-lung transplantation

45. Management...
 Open pulmonary thromboendarterectomy
 Developed by Dr. Stuart Jamieson
 Median sternotomy on cardiopulmonary
bypass & hypothermia
 Pericardial incised longitudinally and
attached to the wound edges
 Pulmonary arteries opened
 Clots and scar tissues dissected

46. Management...
 Alternative therapies for or CTEPH
 For:
 Technically non operable
 Unacceptable high surgical risks
 Includes:
1. Balloon angioplasty of the pulmonary
vasculature
2. Riociguat – guanylate cyclase stimulator

47. Prevention
 Early ambulation
 Prophylaxis anticoagulants
 Calf muscle massage
 Stockings

48. References
1. Pulmonary Embolism: Pathophysiology, Diagnosis, Treatment: Eleni
Kostadima, Epaminondas Zakynthinos
2. Brunicardi, F. Charles, et al. Schwartz's Principles of Surgery. 11th ed.,
McGraw-Hill, 2019.
3. Pearson, F. Griffith, et al. Pearson's Thoracic and Esophageal Surgery.
Churchill Livingstone/Elsevier, 2008.
4. “Pulmonary Embolism.” Sabiston & Spencer Surgery of the Chest, by
Frank W. Sellke, 9th ed., vol. 1, Elsevier, 2016.
5. Konstantinides, Stavros & Meyer, Guy & Becattini, Cecilia & Bueno,
Héctor & Geersing, Geert-Jan & Harjola, Veli-Pekka & Huisman, Menno
& Humbert, Marc & Jennings, Catriona & Jiménez, David & Kucher, Nils
& Lang, Irene & Lankeit, Mareike & Lorusso, Roberto & Mazzolai, Lucia
& Meneveau, Nicolas & Ni Ainle, Fionnuala & Prandoni, Paolo &
Pruszczyk, Piotr. (2019). 2019 ESC Guidelines for the diagnosis and
management of acute pulmonary embolism developed in collaboration
with the European Respiratory Society (ERS). European Heart Journal.
41. 10.1093/eurheartj/ehz405.