Pleural effusion Flashcards Preview

Respiratory > Pleural effusion > Flashcards

Flashcards in Pleural effusion Deck (15)
Loading flashcards...
1
Q

What is exudate?

A

An exudate is a cloudy fluid that seeps out of blood vessels to surrounding tissues as a result of inflammation and injury. It is generally made up of cells with recognizable amounts of protein and other solutes (>30g/L, LDH > 200 units/L).
In the case of blood, plasma proteins, red blood cells, white blood cells, and platelets may also be present. An exudate may also be pus-like.

exudates are produced from inflammation and injury,

2
Q

What is transudate?

A

a transudate is a clear solvent or sometimes a solute that flushes out to extracellular spaces of tissues as a result of imbalanced hydrostatic and osmotic pressures. It has considerably lower protein content compared to an exudate.

transudates are caused by conditions that are related to increased hydrostatic pressure, such as cirrhosis, nephrotic syndrome, and left ventricular heart failure.

3
Q

causes of exudate effusion?

A

bacterial pneumonia,
carcinoma of the bronchus,
TB
connective tissue disease (RA, SLE).

Rare causes include post-MI syndrome, pancreatitis, mesothelioma, sarcoidosis, yellow-nail syndrome.

4
Q

causes of transudate effusion

A

hypoproteinaemia: kidney, liver, enteropathy causing protein lost, hypothyroidism, constrictive pericarditis, ovarian tumour
heart failure

5
Q

What would cause a milky effusion?

A

Obstruction of the thoracic duct: a chylothorax

6
Q

Clinical signs of Pleural effusion

A

A pleural effusion is an excessive accumulation of fluid in the pleural space.
Chest wall movement is reduced on the affected side, and the mediastinum is shifted away. P
ercussion will elicit a stony dull sound. Depending on severity, breath sounds and vocal resonance may be reduced or absent.
The only symptom of the actual effusion is breathlessness, but on enquiry patients may reveal other symptoms of causative disease, especially pleuritic pain.

7
Q

What is an empyema and how does it present?

A

An empyema is the presence of pus in the pleural space (yellow and turbid). It may be a complication of bacterial pneumonia or TB, rarely from transfer of subphrenic abscess through the diaphragm or infection of a haemothorax.
An empyema should be suspected in the same way as an abscess – if a patient stays pyrexial/unstable despite treatment. Symptoms include fever, rigors, malaise, pleuritic pain, SOB. Signs are similar to those of an effusion.

8
Q

Discuss the investigation of a unilateral pleural effusion

A

CXR is often first line investigation if effusion is suspected, and may show un/bilateral blunting of the costophrenic angle. CT is similarly useful in identification but confers a higher dose of radiation – however, if malignancy or metastases are supposed to be the cause, it may shine more light on this.

9
Q

Difference between pleural tap and pleural biopsy?

A

Pleural tap is indicated for diagnostic purposes in all but the smallest effusions. A needle attached to a syringe is inserted through an intercostals space over an area of dullness, and thoracocentesis is performed. This procedure may be performed under ultrasound to localise fluid. Large amounts of fluid may be withdrawn, slowly, to relieve SOB. Gross examination and cytology can give information about the character of effusion and possible cause.

Pleural biopsy may be performed using Abram’s needle and is useful for diagnosing malignant effusions or TB.

10
Q

what might indicate pleural effusion upon examination??

A

Following clinical suspicion, respiratory examination will reveal stony dullness to percussion, a loss of breath sounds and reduced vocal fremitus.

11
Q

What is asbestos composed of and why does it cause

A

Asbestos is a mixture of silicates of iron, magnesium, nickel, cadmium and aluminium, and occurs naturally as a fibre. It is remarkably resistant to heat, acid and alkali. 90% of asbestos is chrysolite, 6% is crocidolite, and 4% amosite.
crocidolite, being the most likely to cause asbestosis or mesothelioma. Crocidolite is invulnerable to enzymatic degradation by the immune system. Fibres are up to 50mm in length and 1-2um in width. Asbestos causes restrictive ventilatory defects.

12
Q

difference between asbestosis and mesothelioma?

A

Asbestosis is a fibrosis of the lungs due to asbestos dust irritation. It may include fibrosis of pleura. It is a progressive disease characterised by breathlessness and clubbing, with bilateral, basal, end- inspiratory crackles on auscultation. Fibrosis may be identified on CT scan, as honeycomb lung, but not on CXR. No treatment is known but corticosteroids may be given. CT may reveal pleural plaques.

Mesothelioma (tumour of the pleura) may be caused by asbestos irritation. Generally there is a lag between exposure and disease development (20-40 years). The number of cases in the UK has risen since 1980 and is expected to peak between 2010 and 2020. Typical presentation includes persistent chest wall pain and pleural effusions. If a biopsy is taken, radiology should be used to avoid cancer seeding down the track of the needle.

13
Q

What is Coal worker’s pneumoconiosis?

A

Coal worker’s pneumoconiosis is a disease caused by coal dust particles approx 2-5um in diameter. The severity of syndrome is graded, into simple (cat 1, 2, 3) and progressive massive fibrosis (PMF).

14
Q

Define simple pneumoconiosis

A

Simple pneumoconiosis reflects deposition of coal dust in the lung. It produces fine micronodular shadowing on the CXR. Miners who develop COPD may be compensated, depending on CXR appearance: category 1 – small round opacities definitely present but few in numbers (unlikely to be compensated and unlikely to progress to PMF); category 2 – opacities numerous but normal lung markings visible (7% progress to PMF); category 3 – very numerous and lung markings obscured (30% progress to PMF). Compensation depends on CXR appearance + COPD.

15
Q

Define progressive massive fibrosis (PMF).

A

In PMF, patients develop round; black, fibrotic masses in the apices of the lungs, several centimetres in diameter. Necrotic central cavities may develop. Immune complexes are implicated in the disease, through fibrogenic promotion factor – analogous to development of nodules in coal miners with RA (Caplan’s syndrome), a Type III hypersensitivity. Rheumatoid factor and anti-nuclear antibodies are often present in patients’ serum (and in asbestosis pts). Apical destruction ensues, resulting in emphysema and airway damage. It is a mixed restrictive and obstructive ventilatory defect, with reduced gas transfer. Patients display effort dyspnoea and may produce black sputum. Disease may progress or develop once exposure to coal dust has been withdrawn

Pure carbon is biologically inert and is simply removed by macrophages to aggregate in lymph nodes. Damage in pneumoconiosis is generally due to the presence of silicates and other pollutants..