Download Pulmonary embolism

Pulmonary embolism
Pulmonology Refresher Course
27 May 2011
Dr. JM Nel
Department of Critical Care
Incidence

Pulmonary embolism (PE)
– In 1% of patients admitted to hospital
– Accounts for 5% of in hospital deaths
– Common mode of death
 Cancer
 Stroke
– Most common cause of death in pregnancy
Etiology

Majority (75%)
 Propagation of lower
limb DVT

Other (rare)






Amniotic fluid
Placenta
Air
Fat
Tumour
Septic emboli (from
endocarditis affecting
tricupid or pulmonary
valves)
Risk factors

Surgery
– Major abdominal/ pelvic
surgery
– Hip/ knee surgery
– Post- operative intensive
care

Obstetrics

Cardiorespiratory disease

Lower limb problems

Malignant disease

Miscellaneous
– Pregnancy/ puerperium
– COPD
– Congestive cardiac failure
– Other disabling disease
– Fracture
– Varicose veins
– Stroke/ spinal injury
– Abdominal pelvic
– Advanced/ metastatic
– Concurrent chemotherapy
–
–
–
–
–
Increasing age
Previous proven VTE
Immobility
Thrombotic disorders
Trauma
Clinical features

Clinical features vary
DIFFICULT DIAGNOSIS
Clinical features
ASK 3 QUESTIONS
– Is the presentation consistent with PE ?
– Does the patient have risk factors for PE ?
– Is there another diagnosis that can explain
the patients presentation ?
Clinical features

Clinical features
– Acute massive PE
– Submassive PE
– Acute small/ medium PE
Acute massive PE

Symptoms
 Collapse
 Central chest pain
 Severe dyspnoea

Signs
 Major circulatory
collapse
–
–
–
–
–
–
Tachycardia
Hypotension
Increased JVP
Loud P2
Parasternal heave
RV gallop rhythm
 Severe cyanosis
Acute small/medium PE

Symptoms
 Pleuritic chest pain
 Restricted breathing
 Haemoptysis

Signs







Tachycardia
Pleural rub
Raised hemidiaphragm
Crackles
Effusion
Low- grade fever
Normal BP
Submassive PE
WHAT’S THAT ???
Submassive PE

Massive PE
 RV Strain/dilatation
 Low BP

Submassive PE
 RV Strain/dilatation
 Normal BP
Investigations

CXR

Heart sonar

ECG

Other biomarkers

Arterial blood gas

Imaging

D- dimer
Investigations: Chest x- ray

High index of suspicion if normal CXR
– Acute dyspnoec and hypoxemic patient

Exclude differential diagnoses
 Heart failure
 Pneumonia
 Pneumothorax
Investigations: Chest x- ray

Radiographic
appearances
– Pleural effusion
– Pulmonary opacities
– Oligaemia of lung
field
– Wedge shaped
opacity
– Enlarged pulmonary
artery
– Horizontal linear
opacities
– Elevated
hemidiaphragm
Investigations: Chest x- ray

Acute massive PE
 Usually normal
 Oligaemia

Acute small/ medium PE
 Pleuropulmonary opacities
 Pleural effusion
 Linear shadows
 Raised hemidiaphragm
Investigations: ECG

Common but non- specific

Most common
– Sinus tachycardia

Exclude other differential diagnoses
– Acute myocardial infarction
– Pericarditis
Investigations: ECG

Massive/Submassive
PE
– Acute cor pulmonale






S1 Q3 T3
T- wave inversion
RBBB
P-wave pulmonale
Right axis
Small/ medium PE
 Sinus tachycardia
Investigations: A- blood gas

Typical A- blood gas
 Low PaO2
 Normal or low PaCO2
Investigations: D- dimer

Degradation product

Positive D- dimer
– High negative
predictive value
– Screening test for PE
– ELISA based Ddimer superior
sensitivity

Other causes for
elevation








Myocardial infarction
Pneumonia/Infection
Sepsis
Pregnancy
Malignancy
Hospitalised patients
Elderly
Trauma
Investigations: Heart sonar

Massive/Submassive PE
 Acute dilatation of the
right heart
 Pulmonary hypertension
 Thrombus can be seen
LOOK FOR:
RV
DYSFUNCTION
RV DYSFUNCTION
•RV enlargement
•Hypokinesis of free wall
•Leftward septal shift
•PHT
Investigations: Other
biomarkers

Cardiac troponin
Detects myocardial
injury
 Risk stratification
 Elevated in massive PE
– 6-12 hours after
symptoms

Pro-BNP
Detects myocardial
dysfunction
 Increases with
ventricular stretching
 But also elevated in
other causes of
PHT/congestive heart
failure
Investigations: Other
biomarkers
Normal levels:
•Low risk of death/complications
Increased levels:
•Cannot predict early death
•RISK ASSESSMENT
•Do not dictate need for early thrombolysis
Investigations: Imaging

V/Q scans
– If normal
 Excludes PE
– If underlying chronic cardiopulmonary
pathology (COPD, congestive cardiac
failure)
 Majority of scan indeterminate
Investigations: Imaging

CT pulmonary angiography
– Difficult to detect small peripheral emboli

Duplex doppler of legs
– DVT in leg

Pulmonary angiography
– Gold standard
Management

General measures

Anticoagulation

Thrombolytic therapy

Caval filters
Management: General

Oxygen for
hyoxaemic patients
– Keep arterial oxygen
saturation > 90%

Analgesics
– Opiates
 Careful in hypotensive
patients

Avoid diuretics and
vasodilators

Treat hypotension
– IVI fluids
– Inotropic agents of
limited value
Confirmed PE
ECHO
RV dysfunction
NO
YES
Hemodynamically
Stable ?
Low risk
Non-massive PE
YES
Anticoagulate
UFH
LMWH
Submassive PE
Anticoagulate
NO
Massive
PE
Thrombolysis if no
contra-indication
Management: Anticoagulation

Start immediately
– High or intermediate
probability of PE

Low molecular weight
heparin sc
–
–
–
–
Clexane
Give according to weight
Reduces mortality in PE
Reduces the propagation
of clot and risk of
further emboli
– Give at least 5 days
– Start Warfarin
– Stop Clexane when INR is
>2
Management: Anticoagulation

Duration of Warfarin therapy
– If underlying prothrombotic risk or
previous emboli
 For life
– If identifiable and reversible risk factor
 3 Months
– If idiopathic
 6 Months
Management: Thrombolytic
therapy

Acute massive pulmonary embolism
– Patient shocked
– Improves outcome

If normal BP
– Unsure if advantage above heparin

High risk of intracranial haemorrhage
– Screen patient for haemorrhagic risk
Management: Caval filters

Filter inserted in inferior vena cava
 Below origin of renal vessels

Indications
 Recurrent PE despite adequate anticoagulation
 Contraindication to anticoagulation
Prognosis

Lowest recurrence after operation

If right ventricular dysfunction
 Risk of cardiogenic shock
 Increased risk of death

If pulmonary hypertension and right
ventricular dysfunction after 6 weeks
 Increased risk to develop right heart failure over next 5
years
Pulmonary Embolism:
Case Studies
Pulmonary embolism

Case Presentation 1:
–
–
–
–
–
–
–
64 year old male
Previous hip surgery 20 days ago
Sudden dyspnoea
Pleuritic chest pain
Hypoxic
BP 130/80
Clinically DVT
Pulmonary embolism
DIFFERENTIAL DIAGNOSIS
 Pulmonary embolism
 Pneumonia
 Pneumothorax
 Musculoskeletal chest pain
Pulmonary embolism
ASK 3 QUESTIONS
– Is the presentation consistent with PE ?
– Does the patient have risk factors for PE ?
– Is there another diagnosis that can explain
the patients presentation ?
Pulmonary embolism
WHAT NOW ???
Pulmonary embolism

CXR
– Exclude differential diagnoses
 Heart failure
 Pneumonia
 Pneumothorax

High index of suspicion if normal CXR
– Acute dyspnoeac and hypoxaemic patient
Pulmonary embolism

ECG
– Exclude other differential diagnoses
 Acute myocardial infarction
 Pericarditis

Most common
– Sinus tachycardia
Pulmonary embolism

Arterial bloodgas

Low PaO2
Pulmonary embolism

D- dimer

POSITIVE
Pulmonary embolism


Heartsonar

Massive/Submassive PE
– Acute dilatation of the
right heart
– Pulmonary hypertension
– Thrombus can be seen
NORMAL

Alternative diagnoses
– Left ventricular failure
– Aortic dissection
– Pericardial tamponade
Pulmonary embolism

Duplex doppler of legs

DVT in leg
Pulmonary embolism

V/Q scan

PULMONARY EMBOLISM
Pulmonary embolism: Management

General measures
– Oxygen for all hyoxaemic patients
 Keep arterial oxygen saturation > 90%

Anticoagulation
– Clexane 80mg bd sc
 Give at least 5 days
– Warfarin
– Stop Clexane when INR is > 2
Pulmonary embolism: Management

HOW LONG DO I
TREAT THIS
PATIENT WITH
WARFARIN ???

Duration of Warfarin
therapy
– If underlying
prothrombotic risk or
previous emboli
 For life

3 Months
– If identifiable and
reversible risk factor
 3 Months
– If idiopathic
 6 Months
Pulmonary embolism

Case Presentation 2:
–
–
–
–
–
–
–
28 year old lady
Oral contraceptives
10 hour flight
Sudden dyspnoea
BP 90/40
Loud P2/ Increased JVP
Hypoxic
Pulmonary embolism
DIFFERENTIAL DIAGNOSIS
 Massive pulmonary embolism
 Myocardial infarction
 Pericardial tamponade
 Aortic dissection
Pulmonary embolism

CXR

NORMAL
Pulmonary embolism

ECG
– S1 Q3 T3
– RBBB

Arterial bloodgas
– Low PaO2

D- dimer
– POSITIVE
Pulmonary embolism

Heartsonar
– Right ventricular dilatation
– Increased pulmonary pressure
Pulmonary embolism

CT pulmonary angiography
MASSIVE PULMONARY EMBOLISM
Pulmonary embolism: Management

General measures
 Oxygen for all hypoxaemic patients
– Keep arterial oxygen saturation > 90%
 Treat hypotension with IVI fluids
Thrombolytic
 RV dilatation
 Low BP
therapy
Pulmonary embolism: Management

Complications of thrombolytic therapy
 Intracranial haemorrhage
 Haemorrhage at other sites
 Anaphylaxis
Pulmonary embolism

Case Presentation 3:
–
–
–
–
–
–
–
28 year old lady
Oral contraceptives
10 hour flight
Sudden dyspnae
BP 130/80
Loud P2/ Increased JVP
Hypoxic
Pulmonary embolism

CXR

NORMAL
Pulmonary embolism

ECG
– S1 Q3 T3
– RBBB

Arterial bloodgas
– Low PaO2

D- dimer
– POSITIVE
Pulmonary embolism

Heartsonar
– Right ventricular dilatation
– Increased pulmonary pressure
Pulmonary embolism

CT pulmonary angiography
PULMONARY EMBOLISM
Pulmonary embolism

Patient has normal BP

Patient has RV strain
SUBMASSIVE PULMONARY EMBOLISM
Confirmed PE
ECHO
RV dysfunction
NO
YES
Hemodynamically
Stable ?
Low risk
Non-massive PE
YES
Anticoagulate
UFH
LMWH
Submassive PE
Anticoagulate
NO
Massive
PE
Thrombolysis if no
contra-indication
Thrombolytic therapy

Associated with rapid resolution of
radiographic abnormality
 No reduction in
– In submassive PE
mortality !!!
Thrombolytic therapy

Indicated only in hemodynamically
unstable patients !!!
– SBP < 90mmHg or drop of 40mmHg for at
least 15 minutes
– Best if given in 48 hours, still benefit after
14 days (if still symptomatic)

All must be followed by therapeutic
anticoagulation
Submassive PE

To thrombolise or not to thrombolise
THAT REMAINS THE QUESTION !!!