Pulmonary And Pleural Lung Disease. Flashcards
What is the pulmonary oedema? What pattern of disease does it cause?
Accumulation of fluid in the lung interstitium and alveolar spaces. Causes a restrictive pattern of disease.
What are some of the causes of pulmonary oedema?
Haemodynamic from increased hydrostatic pressure.
Cellular injury e.g. Alveolar lining cells or alveolar endothelium.
Can be localised e.g. Pneumonia.
Or general e.g. ARDS.
What are the two types of ARDS?
Alveolar damage syndrome (DADS)
Or
Shock lung.
What can cause shock lung?
Sepsis, diffuse infection, severe trauma and O2 damage.
What is the pathogenesis of ARDS?
Injury e.g. From a bacterial endotoxin leading to:
Infiltration of inflammatory cells
Cytokines
Oxygen free radicals and injury to cell membranes.
What pathological findings do we have in ARDS?
Fibrous exudate lining the alveolar walls.
Cellular regeneration and inflammation.
What are the possible outcomes of ARDS?
Death, resolution or fibrosis e.g. Chronic restrictive lung disease.
What two arterial supplies does the pulmonary circulation get?
Bronchial and pulmonary arteries.
What two types of hypertension are there?
Primary and secondary.
What type of pulmonary hypertension is more common?
Secondary
What can cause pulmonary hypertension?
What are the mechanisms behind them?
Hypoxia (vascular constriction).
Congenital heart disease (increased flow).
Blockage (PE) or loss of vascular bed (emphysema)
Back pressure from LVH.
Morphology change of vessels e.g. Intima thickening by fibrosis and medial hypertrophy of arteries.
RVH.
Cardiac left to right shunt.
Drugs e.g. Appetite suppressants.
What are some cardiac causes of pulmonary hypertension?
LVF, mistral regurg or stenosis and cardiomyopathy e.g. From alcohol or a virus.
What are the signs of pulmonary hypertension?
Central cyanosis if hypoxic, dependent oedema, raised JVP with V waves (due to tricuspid regurg) right ventricular heave at left para sternal edge, tricuspid regurg murmur and enlarged pulsatile liver.
What investigations do we do for pulmonary hypertension?
ECG, CXR, sats and ABGs, pulmonary function tests, echo, D dimers, VQ scan if PE suspected, CT pulmonary angiogram, cardiac MRI and auto-antibodies if vasculitis supspected.
How do we diagnose primary pulmonary hypertension?
Diagnosis by exclusion of other causes. Progressive shortness of breath and signs of right sided heart failure.
What is the pharmacological treatment of primary pulmonary hypertension?
Prophylactic anticoagulation - warfarin.
PO vasodilators e.g. Calcium channel blockers - oral nifedipine, diltiazem.
Endothelin antagonists - oral bosentan
PDE5 inhibitor - oral sildenafil.
Prostanoids - IV epoprostenol or inhiloprost.
Guanylate cyclase stimulator - oral riociguat.
What is cor pulmonale?
Pulmonary hypertension complicating lung disease causing right ventricular hypertrophy.
What is the pathogenesis of cor pulmonale?
Hypoxaemic pulmonary vasoconstriction causing increased ventricular afterload. This causes right ventricular hypertrophy which leads to dilation and failure.
How do we treat cor pulmonale?
Optimise small degree of reversibility with high dose B2 agonists and anticholinergics.
Remove hypoxic stimulus with home 02.
Thiazides or loop diuretic to remove oedema.
What type of cells make the pleura and what do they do to fluid?
How does disease affect this?
Mesothelial cells that are designed to absorb fluid.
Hallmark of pleural disease is effusion.
How much pleural fluid of we normally have and what type of fluid is it?
Serous fluid, usually around 4mls.
What happens to the pleura at the root of the lung?
The two layers combine, meaning the root of the lung has no pleural coverage. The layers combine to form the pulmonary ligament which runs inferiorly and attaches the root of the lung to the diaphragm.
What can the parietal pleura sense and what is its innervation?
Senses pain. Is supplied by the intercostal and the phrenic nerves.
What does the visceral pleura sense and what is its nerve supply?
Sensitive to stretch. It contains vasomotor fibres and sensory endings of the cranial nerve X for respiratory reflexes.
What is a pleural effusion and what does it look like on X-ray?
It is common in numerous diseases and is an abnormal collection of fluid in the pleural space.
Looks almost completely white on X-ray and we can see the line of the lung edge.
What effusions should we be particularly worried about?
Unilateral effusions in a smoker or patient with significant asbestos exposure.
What two categories of effusion do we have and what is the difference?
Transudates - protein under 30g/L
Exudates - protein over 30g/L
What condition gives a pleural effusion that we dont have to drain or aspirate?
Heart failure.
What tests do we do to find the cause of pleural effusions?
History and examination.
PA CXR and lateral.
Pleural aspirate if it’s not convincingly caused by heart failure.
CT
Repeat cytology
Pleural biopsy and bronchoscopy if concern of malignancy.
If the pleural fluid is bloody what does this mean?
Trauma, malignancy, infection and infarction.
If the pleural fluid is straw coloured what does this mean?
Cardiac failure and hypoalbuminaemia.
If the pleural fluid is turbid/milky what does this mean?
Empyema or chylothorax.
If the pleural fluid is foul smelling what does this mean?
Anaerobic empyema.
If the pleural fluid is viscous what does this mean?
Mesothelioma.
If the pleural fluid contains food particles what does this mean?
Oesophageal rupture.
What criteria do we use to determine if pleural fluid is exudative?
Lights criteria.
What are the lights criteria for exudative pleural fluid?
A serum protein ration of over 0.5
Serum LDH level of over 6.
A pleural fluid LDH of over two thirds of the upper ,I it if normal serum LDH.
If the fluid has any of the above it is exudative.
If there are neutrophils present in pleural fluid, what diagnosis does this point is too?
Parapneumonic or PE.
If there are mononuclear cells present in pleural fluid, what diagnosis does this point is too?
Chronic effusions.
If there are mesothelial cells present in pleural fluid, what diagnosis does this point is too?
Inflammatory process diseases like TB.
If there are lymphocytes present in pleural fluid, what diagnosis does this point is too?
Most commonly TB
Can also be sarcoidosis, lymphoma or rheumatoid.
What are the common causes of pleural transudate?
Heart failure, liver cirrhosis, nephrotic syndrome and atelactasis.
What are the not so common causes of pleural transudate?
Hypothyroidism, constrictive pericarditis, meigs syndrome and urinothorax.
What is meigs syndrome?
Ovarian or pelvic malignancy.
What does parapneumonic mean?
In the pleural space.
What are common pleural exudate causes?
Parapneumonic, PE, malignant effusions, rheumatoid or mesothelioma.
What are not so common causes of pleural exudate?
TB, oesophageal rupture, pancreatitis, SLE, post cardiac injury, radiotherapy, uraemia, chylothorax etc.
What microbiology tests do we do for pleural effusions?
Gram stain and microscopy.
Culture.
PCR, SFB stain and liquid culture.
What is the normal pH of pleural fluid?
7.6
What does it mean in the pH of the pleural fluid is under 7.3?
Suggest pleural inflammation
What does it mean in the pH of the pleural fluid is under 7.2?
What causes this?
Requires drainage.
Usually caused by parapneumonic or empyema.
When do we get a low glucose level in pleural fluid?
Infection, TB, rheumatoid, malignancy, lupus or oesophageal rupture.
How do we treat effusions?
Treat underlying cause.
Throacentesis (chest drainage)
Pleurodesis for malignant effusions.
Talc or surgery.
What should we never do to a bubbling chest drain?
Clamp it.
What type of chest drain uses a guidewire?
Seldinger.
What are the indications for chest drain insertion?
Tension pneumothorax after initial needle decompression.
Symptomatic pneumothorax.
Complicated parapneumonic effusion and empyema.
Malignant pleural effusion
Traumatic haemopheumothorax.
What are the complications of chest drains?
Pain, inadequate placement, surgical emphysema, infection, haemorrhage, organ damage, re expansion pulmonary oedema.
Vasovagal reactions and rarely sudden death.
Is asbestosis a pleural disease?
No.
What different types of asbestos related disease do we get in the pleura?
Benign pleural plaques Benign pleural effusions Diffuse pleural thickening Rounded actelectasis Mesothelioma.
What is rounded actelectasis?
Folded lung.
What latency period can asbestos have?
Up to 40 years.
What are benign pleural plaques?
What do they look like on X-ray?
How common are they?
What is the treatment?
Discrete areas of pleural thickening that can calcify.
They are usually symmetrical and look like bright white lines on X-ray.
They are common.
They aren’t premalignant so don’t need follow up.
What are benign asbestos pleural effusions?
What is the treatment?
Early manifestation of pleural disease that are small and unilateral and usually resolve spontaneously. They give blood stained exudate and so we must exclude mesothelioma.
We treat the symptoms.
What happens during diffuse pleural thickening?
What are the symptoms?
What do investigation show?
Extensive fibrosis of visceral pleura with adhesion to the parietal pleura.
SOB and chest pain are common.
Shows restrictive spirometry and can show as costophrenic angle blunting on X-ray and can see the lines of the pleura easily.
What is a mesothelioma?
Malignant tumour of the pleura or peritoneum. Not associated with smoking and is not dose related. It often invades the chest wall and has a poor prognosis.
What are the symptoms of mesothelioma?
Chest pain, shortness of breath and sweating.
What investigations do we do for mesothelioma?
Aspirate pleural fluid, CXR and CT.
If there is a moderate to large effusion, pleural mass or thickening, lung entrapment or local invasion then do a biopsy under CT, USS or direct vision.
What is the treatment for mesothelioma?
Radiotherapy, palliative care, surgery if very fit and chemo.
What special consideration do we need to think of for mesothelioma?
Patients are due compensation and the PF must be informed of their deaths.
What kind of patients is pneumothorax more common in?
Tall thin men, smokers, cannabis users and those with underlying lung disease.
What is a primary pneumothorax?
Happens to normal lungs or as a result of apical bullae rupture.
What is a secondary pneumothorax?
One caused by an underlying lung disease e.g. COPD.
What are the symptoms of pneumothorax?
Shortness of breath, hypoxia and acute onset pleuritic chest pain.
What are the signs of a pneumothorax?
Tachycardia, hyper resonant percussion note, reduced expansion, quiet breath sounds on auscultation and ham and sign (click on auscultation left side).
What are the investigations for a pneumothorax?
Chest X-ray usually sufficient.
ABG.
What percentage of pneumothorax is one with a 2cm rim?
50% pneumothorax by volume.
What is the management of a pneumothorax?
Oxygen if no drain, no treatment if symptomatic and small. Aspiration may avoid chest drain but may be time consuming and may fail.
May need chest drain
Suction drain
Surgical intervention.
What are the indications for surgical intervention of pneumothorax?
Second ipsilateral or first contra lateral.
Bilateral spontaneous.
Persistent air leak over 5 days of drainage.
Spontaneous haemothorax.
Risky professions after first collapse e.g. Pilots and divers.
What is the follow up after pneumothorax?
CXR, discussion about flying and diving. Risk of recurrence and smoking cessation.
What is a major complication of a tension pneumothorax?
Can lead to cardiac arrest.
What are the signs of a tension pneumothorax?
Trachea deviated to the opposite side, hypotension, raised JVP and reduced air entry on the affected side.
Where is needle decompression for a tension pneumothorax done?
Second intercostal space anteriorly in the mid clavicular line.
