Pulmonary Circulation/haemoptysis Flashcards
where do most emboli originate from in PE
the deep veins of the leg
more rarely they can originate fro the upper limb
Paradoxical emboli can present in the arterial system such as in a cerebrovascular event. What three conditions can produce paradoxical emboli?
conditions producing a right to left shunt:
1) atrial/ventricular septal defects (patent foramen ovale, post MI, pulmonary hypertension)
2) Patent Ductus Arteriosus
3) AV malformations
which pulmonary artery passes through the pericardium for the longest
the right pulmonary artery passes horizontally through the pericardium anterior to the left main bronchus.
From which arteries do the bronchial arteries arise?
RIGHT: the third right intercostal artery (a branch off the aorta)
LEFT: arise at the level of T5
superior–> antero-medial surface of the aortic arch (lateral to carina)
inferior –> directly from the aorta
what are the differences between the bronchial and pulmonary circulations? what links them?
the bronchial arteries:
- smaller proportion of cardiac output (pulmonary arteries receive entire cardiac output)
- higher pressure as systemic
-supplies blood to air ways
- can cause massive haemoptysis
They are linked by the ligamentum arteriosum
what clinical sign is present in a patent ductus arteriosus
continuous machine like murmur
what is transposition of the great vessels and how is it treated?
the aorta and the pulmonary trunk are switched and therefore the baby is reliant upon the ductus arteriosus. The child becomes symptomatic upon the closure of the ductus arteriosus 2-3 weeks after birth.
treatment is with prostaglandins to maintain patency followed by surgery.
what is Virchow’s triad and what does it describe
The predisposition to thrombosis following an alteration in:
1) blood flow
2) blood constituents
3) injury to the endothelium
what might alter blood flow
SLUGGISH BF: - immobility (incompetent venous valves, compression of VC, cardiac failure) - AF - cardiomyopathy and dilated ventricle - ventricular and aortic aneurysms TURBULENCE: - prosthetic/infected valves - bifurcation of vessels
What might alter the constituents of blood
- increased cells (polycythaemia, thrombocythaemia, leukaemia)
- dehydration
- nephrotic syndrome
- disturbed clotting factors
what might endothelial inury
- surgery (pressure on limbs)
- trauma
- inflammation/vasculitis
- hypertension
- bacterial toxins
- chemo/radiotherapy
- turbulent flow
- smoking
- hyperlidiaemia
list 6 causes of venous emboli
1) DVT
2) fat embolism
3) gas embolism
4) amniotic fluid embolism
5) tumour embolism
6) schistosomiasis
list 8 causes of arterial emboli
1) AF
2) mitral stenosis
3) atrial myxomas
4) thrombi overlying MIs
5) ventricular or aortic aneurysm
6) infected or prosthetic valve
7) atherosclerotic plaque
8) vasculitis
list the 4 major causes of atheromatous plaques
1) hypertension
2) hyperlipidaemia
3) cigarette smoking
4) diabetes mellitus
what is the definition of pulmonary hypertension
MEAN pulmonary arterial pressure of >25mmHg measured at rest from right heart catheterisation
pulmonary hypertension can be split into 5 groups, breifly describe each one
1) pulmonary arterial hypertension - right sided heart disease
2) pulmonary venous hypertension - left sided heart disease
3) pulmonary hypertension associated with hypoxaemia - respiratory disease (esp interstitial lung)
4) pulmonary hypertension due to chronic thromboembolic disease
5) miscellaneous (sarcoidosis, histiocytosis X, lymphangiomatosis, compression of pulmonary vessels)
list some connective tissue disorders associated with pulmonary arterial hypertension
Scleroderma SLE mixed connective tissue disease antiphospholipid disease rheumatoid arthritis
what are the symptoms of pulmonary hypertension
often silent until right heart failure prevails, often misdiagnosed as athma, COPD or hysteria
- progressive dyspnoea
- fatigue
- palpitations
- chest pain
- cough/haemoptysis
- syncope
what ECG changes might you expect in pulmonary hypertension
Right ventricular hypertrophy:
- right axis deviation (isoelectric lead V5,6 instead of 3,4; negative QRS in lead I and tall QRS in lead II)
Right atrial enlargement:
- Tall peaked T-waves
- P-wave >2mm in lead II
what might you see on an echo in pulmonary hypertension
tricuspid regurgitation
what might you see on a CXR in pulmonary hypertension
hilar enlargement
enlargement of the pulmonary arteries
pruning of the peripheral arteries
why should pregnancy be avoided in pulmonary arterial hypertension
high mortality rate (30-50%) therefore patients should be counselled about using contraception:
- barrier methods
- POP
- mirena coil
what causes septic emboli
IV DRUG USERS!!!
pelvic thrombophlebitis
infected venous catheter/pacemaker wire
skin infections
usually staphylococci
describe the presentation of an acute minor PE
often with infarction:
- SOB
- pleuritic pain
- haemoptysis
- fever
