Pleural effusion

Published on 02/04/2015 by admin

Filed under Internal Medicine

Last modified 02/04/2015

Print this page

This article have been viewed 1116 times

97 Pleural effusion

Instruction

Examine this patient’s chest.

Examine this patient’s chest from the back.

Examine this patient’s chest from the front.

Salient features

History

• Pleuritic pain (made worse on coughing or deep breathing)

• Cough (pneumonia, TB)

• Haemoptysis (associated parenchymal involvment in bronchogenic carcinoma or TB)

• Shortness of breath (large effusions, cardiac failure)

• Exposure to asbestos (mesothelioma)

• Nephrotic syndrome.

Examination

• Decreased movement on the affected side

• Tracheal deviation to the opposite side

• Stony dull note on the affected side

• Decreased vocal resonance and diminished breath sounds on the affected side.

Proceed as follows:

• Comment on aspiration marks

• Percuss for the upper level of effusion in the axilla

• Listen for bronchial breath sounds

• Listen for aegophony at the upper level of the effusion

• It is important to elicit any evidence of an underlying cause, such as clubbing, tar staining, lymph nodes, radiation burns and mastectomy, raised JVP, rheumatoid hands or butterfly rash.

For clinical detection, 500 ml of pleural fluid should be present.

There are five major types of pleural effusion: exudate, transudate, empyema, haemorrhagic pleural effusion or haemothorax and chylous effusion.

The most common causes of pleural effusion in the Western world are congestive heart failure, pneumonia and cancer.

The first step in developing a differential diagnosis of a pleural effusion is to establish whether the effusion is a transudate or an exudate by analysis of fluid obtained at thoracentesis.

Diagnosis

This patient has a pleural effusion (lesion) probably caused by bronchogenic carcinoma and is short of breath at rest (functional status).

Questions

How would you investigate this patient?

• Chest radiography: standard posteroanterior and lateral films detect pleural fluid in excess of 175 ml. Obliteration of costophrenic angle to hemithorax suggest fluid. Subpulmonic effusion can simulate an elevated diaphragm (Fig. 97.1).

• Pleural tap:

• Pleural fluid for determination of the levels of protein, albumin, lactate dehydrogenase (LDH), glucose, cholesterol and cytology; a simultaneous blood sample should be obtained for estimation of glucose, protein, albumin and LDH

• When empyema is suspected or seen, pleural fluid pH should be obtained

• When TB is suspected, pleural fluid adenosine deaminase or lysozyme levels should be determined and Ziehl–Neelsen staining and pleural fluid mycobacterial cultures should be done

• Pleural fluid amylase levels should be estimated when malignancy, pancreatitis or oesophageal rupture is suspected

• In autoimmune disorders, pleural fluid rheumatoid factor or anti-nuclear antibodies should be tested.

• Pleural biopsy: the biopsy specimen is sent for histopathological examination and mycobacterial culture.

Fig. 97.1 The appearance of pleural effusions in chest radiography depend on patient position (also shown in diagramatic form). (A) Upright posteroanterior: a large left pleural effusion obscures the left hemidiaphragm, the left costophrenic angle and the left cardiac border. (B) Supine anteroposterior view: fluid runs posteriorly, causing a diffuse opacity over the lower two-thirds of the left lung, the left hemidiaphragm remaining obscured (this can easily mimic left lower lobe infiltrate or left lower lobe atelectasis). (C) Left lateral decubitus view: pleural effusion can be seen to be freely moving and layering (arrows) along the lateral chest wall.

(With permission from Mettler 2004.)

What are the causes of dullness at a lung base?

• Pleural effusion

• Pleural thickening

• Consolidation and collapse of the lung

• Raised hemidiaphragm.

How would you differentiate between the above?

• Pleural effusion: stony dull note; trachea may be deviated to the opposite side in large effusions

• Pleural thickening: trachea not deviated; breath sounds will be heard

• Consolidation: vocal resonance increased; bronchial breath sounds and associated crackles

• Collapse: trachea deviated to the affected side; absent breath sounds.

How would you differentiate between an exudate and a transudate?

Buy Membership for Internal Medicine Category to continue reading. Learn more here

Related

250 Cases in Clinical Medicine