Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Respiratory > Pulmonary Embolism > Flashcards

Pulmonary Embolism Flashcards

1
Q

what does a blockage in the pulmonary artery result in?

A

decreased oxygenated blood to body and decrease in blood flow downstream in lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are PEs associated with?

A

DVTs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how to DVTs form?

A

Damage to endothelium
Immediate vasoconstriction – limits blood flow
Platelets adhere and become activated by collagen and tissue factor
Recruit more platelets to form plug = primary haemostasis
Coagulation cascade is activated – clotting factors activated ot activate fibrinogen to fibrin – forms mesh around platelets = secondary haemostasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is V/Q mismatch

A

no blood is flowing past alveoli, there are some alveoli getting perfused with fresh air but not with blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what form can the embolus take?

A

clot, fat, air, amniotic fluid etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the consequences of V/Q mismatch

A

Hyperventilation is a physiological response

Release of CO2¬ causing a respiratory alkalosis (↑pH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how does a DVT become a PE

A

Clot grows in size and ↓blood flow, ↑blood pressure
Sometimes break down – fibrin → d-dimers
Increased pressure can cause part of main clot to break free = thromboembolus
Travels to pulmonary arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Virchows Traid?

A

Blood Stasis
Hypercoagulation
Damage to blood vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

mechanism and causes of blood stasis

A

turbulence causes slow or static blood -Platelets contact endothelium – leads to clotting factor adhesion and activation of coagulation cascade
Causes - bed rest, long flights, pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

hypercoagulation mechanism and cause

A

Altered amounts of clotting factors increase primary or secondary haemostasis
Causes - Genetics, surgery, medications (birthcontrol)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

blood vessel damage mechanism and causes

A

exposures tissue factor and collagen

Causes - infections, chronic inflammation, toxins (cigarettes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are other risk factors to developing PE

A

Age, malignancy, infection, FH, immobility, pregnancy (compression and oestrogen), previous DVT/embolism, oestrogen therapy (pill, HRT), trauma, surgery, recent MI, dehydration, smoking, congestive heart failure, antithrombin deficiency, protein C deficiency, inherited clotting deficiencies, obesity, varicose veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is an important risk factor to explore in PE?

A

family history

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the clinical signs of a PE (10)

A

Pyrexia, Cyanosis, Tachypnoea, Tachycardia, Hypotension, Raised JVP Pleural rub, Pleural effusion, Look for signs that could indicate a cause, Atrial fibrillation (rare)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the clinical symptoms of PE (7)

A

Pleuritic chest pain (pain worse on inspiration
Breathlessness
Cough
Haemoptysis – as a result of pulmonary infarct
Dizziness / pre-syncope
Syncope (loss of consciousness/fainting)
Non-pleuritic chest pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Small emboli tend to be…

A

asymtpomatic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

embolism at the pulmonary saddle causes

A

sudden death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

multiple PEs result in

A

pulmonary hypertension, right ventricular failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What criteria makes up the PERC?

A 
Age >50
HR >100
SaO2 on room air <95%
Unilateral leg swelling
Haemoptysis
Recent surgery or trauma
Previous PE or DVT
Exogenous Oestrogen – oral contraceptives, hormone replacement or other oestrogen hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what makes a negative PERC score?

A

all factors must be negative.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what do you if there is a positive PERC score?

A

move onto Wells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what criteria make up the Wells Score?

A 
Clinically suspected DVT = 3
PE is most likely diagnosis = 3
Tachycardia >100bpm = 1.5
Immobilisation >3 days OR surgery – in previous 4 weeks = 1.5
History of DVT or PE in past = 1.5
Haemoptysis = 1
Malignancy = 1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what do different wells scores mean?

A

Score >6.0 — High (probability 59%)
Score 2.0 to 6.0 — Moderate (probability 29%)
Score <2.0 — Low (probability 15%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What diagnostic tests can you do for pulmonary embolism?

A 
D-Dimer
CXR
ECG
VQ Scan
CT Pulmonary angiogram
ABG
Troponin
Echo
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is D-Dimer?

A

fibrin degradation product many factors can cause raised levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What does raised D-Dimer indicate?

A

should only be used as a rule out test in low probability cases based on Wells score
D-Dimer + in a low probability case indicates further investigations
In high probability can skip and go onto imaging

27
Q

what features will be present in a Xray of someone with PE?

A

will often be normal, to exclude other causes

may show raised hemidiaphragm, atelectasis

28
Q

what if the CXR in a PE is normal/bilateral?

A

If the CXR is normal, but the patient is breathless, this raises the suspicion of a pulmonary embolism.
If the CXR has bilateral changes, but the patient only has unilateral pain, this also raises the suspicion of pulmonary embolism.

29
Q

what ECG features are present in PE

A

Sinus tachycardia and T wave inversions
Non specific – t wave changes, new onset AF, RBBB axis deviation
S1Q3T3 pattern - S waves present in lead I, Q waves present in lead III, T wave inversion in lead III

30
Q

what is the predictive value of V/Q scans?

A

negative scan has high negative predicative value, but positive scans are less useful

31
Q

What will ABG show in PE?

A

↓PaO2 ↓PaCO2
Respiratory alkolisis
Metabolic acidosis

32
Q

what will an echo show in a PE?

A

right ventricle strain and dilation

33
Q

what is the drug treatment of a PE?

A

Anticoagulate with LMWH – e.g. dalteparin 200u/Kg/24hrs

34
Q

what is the surgical management of a PE?

A

vena cava filter

used in those who continue to develop thrombus despite anticoagulation

35
Q

when can thrombolysis be used in a PE?

A

when it is deemed massive - 50mg alteplase

36
Q

what preventative measures can be used in PE?

A

compression stockings, exercise, heparin for immobile patients

37
Q

what are the differentials of a PE?

A 
Acute Coronary Syndrome
Pleuritic chest pain
Pneumonia (viral or bacterial)
Pericarditis
Musculoskeletal back pain
Embolus of other cause (fat, amniotic fluid, air)
Dissecting Aortic Aneurysm
Anxiety
Syncope of another cause
Exacerbation of COPD
38
Q

what is a pleural effusion?

A

• Pleural Effusion is when there is excess fluid in the pleural space

39
Q

what is the pleural cavity?

A

Pleural cavity lies between parietal pleura (stuck to chest wall) and visceral pleura (stuck to lungs) – these lie close together
In the thin space, layer of fluid = lubrication to allow lungs to slide back and forth as the expand and contract

40
Q

what are the 2 mechanisms of a pleural effusion?

A

too much fluid is produced

too little is drained away

41
Q

what 2 types of pleural effusions are caused by too much fluid production?

A

transudative and exudative

42
Q

what type of pleural effusion is caused by too little fluid drainage?

A

lymphatic (chylothorax)

43
Q

what are the mechanism of a transudative pleural effusion?

A

raised hydrostatic pressure (BP - blood back up, HF)
reduced oncotic pressure in blood vessels due to reduced protein content (osmosis - low to high, low on BV means fluid leaves into pleural space)

44
Q

what are the causes of a transudative effusion?

A

Hypoalbuminaemia - Nephrotic syndrome, chronic infection, malabsorption, liver failure
Hypothyroidism
Meigs Syndrome
Cardiovascular - Fluid overload, HF, constrictive pericarditis

45
Q

what is the fluid make up of a transudative pleural effusion?

A

Lower protein content, contain fewer cells, fluid typically only contains mononuclear cells, protein content <25g/L

46
Q

what is the mechanism of a exudative effusion?

A

Inflammation of pulmonary capillaries – making them more leaky
Larger spaces between endoltehlial cells allows fluid, immune cells, large proteins to leak out

47
Q

what are the causes of a exudative effusion?

A

Inflammation - RA, granulomatous disorders, SLE, pulmonary infarct
Malignancy - Bronchial carcinoma, Metastasis
Infection - Acute – empyema, Chronic - TB

48
Q

content of exudative effusion?

A

The composition of an exudate varies, but it can include pretty much anything that is in blood. It will nearly always have water and dissolved solutes, and may also have white and red blood cells, as well as platelets. Exudates have a high protein content, Protein content >35g/L

49
Q

mechanism of a lymphatic effusion

A

Thoracic duct us disrupted and lymphatic fluid accumulates in the pleural space

50
Q

causes of lymphatic effusion

A

damage during surgery, tumours in mediastinum (compressing TD)

51
Q

what are the symptoms of a pleural effusion?

A

Reduced chest expansion on the affected side
Mediastinal displacement away from the affected side
Stony dull to percussion
Reduced or absent breath sounds
Reduced or absent vocal resonance
There will be no additional unusual sounds

52
Q

how do you diagnose a pleural effusion?

A

XRay and Thoracentesis

53
Q

what features are present on the CXR of a pleural effusion?

A

Standing – fluid displaces air, dulling of costophrenic angle
Lying down – fluid settles along chest wall (widespread haze)
Flat horizontal line = also pneumothorax present

54
Q

why do you a thoracentesis?

A

to remove fluid and to find a cause of pleural effusion

55
Q

how do you perform a thoracentesis?

A

Percuss the upper border of the effusion, then go 1-2 intercostal spaces below
Use 5-10ml of lideocaine and inject down to the pleura
Insert a 21G needle with syringe just above the ribs upper boarder (to avoid the neurovascular bundle)
Take 10-30ml of fluid
Send sample for: Clinical biochem – glucose, protein, pH, amylase, LDH, Bacteria culture, Cytology, Immunology

56
Q

how do you treat a pleural effusion?

A

treat cause and remove fluid (exudative not transudate)

57
Q

what are the different ways in which fluid can be removed in a pleural effusion

A 
Small effusions (from HF) – diuretics, sodium restriction
Large Effusion (from cancer) – draining with tube, long term chest drains
Large Loculated Effusion (pneumonia, TB) – surgery (as fluid can form paste = emphyema)
58
Q

what does transudative fluid look like?

A

clear

59
Q

what does exudative fluid look like?

A

cloudy

60
Q

what does Empyema/ parapneuoic effusion fluid look like?

A

yellow/white, foul smelling

61
Q

what does the pleural fluid with trauma, maligannyc or pulmonary infarct is the underlying cause?

A

blood

62
Q

what is light criteria used for?

A

distinguish transudative fluid vs exudative fluid

63
Q

what is lights criteria?

A

Is exudative if:
Fluid protein: serum protein >0.5
Fluid LDH: serum LDH > 0.6
Fluid LDH > 2/3 Normal upper limit serum LDG
Also, exudative have cholesterol level >45

Respiratory (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions