Diseases of the pleuraPratap Sagar Tiwari, MD, Internal Medicine

Note: This is lecture class slides for MBBS Students

Topics• Pleurisy• Pleural effusion• Empyema• Pneumothorax• Mesothelioma

Pleura• A pleural cavity is the thin fluid-filled

space between the two pleurae (visceral and parietal) of each lung.

• The pleural cavity contains pleural fluid, which allows the pleurae to slide effortlessly against each other during ventilation.(Normal amount:0.13 ml/kg).1

• Most fluid is produced by the parietal circulation (intercostal arteries) and reabsorbed by the lymphatic system.

• 1. Noppen M. Normal volume and cellular contents of pleural fluid. Curr Opin Pulm Med. 2001 Jul. 7(4):180-2.

Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/

Pleurisy• Pleurisy is not a diagnosis but a term used to describe pleuritic pain

resulting from any one of a number of disease processes involving the pleura.

• There are many possible causes of pleurisy but viral infections spreading from the lungs to pleural cavity are the most common.

• The inflamed pleural layers rub against each other every time the lungs expand to breathe in air. This can cause sharp pain when breathing, also called pleuritic chest pain.

• Pleurisy is a common feature of pulmonary infection and infarction; it may also occur in malignancy.

Clinical features • Sharp pain that is aggravated by deep breathing or coughing is

characteristic. • On examination, rib movement is restricted and a pleural rub (rough ,

scratchy, grating leathery sound as inflamed pleura rub against each other) may be present.

Pleural rub: More often heard on inspiration than expiration, the pleural friction rub is easy to confuse with a pericardial friction rub. To determine whether the sound is a pleural friction rub or a pericardial friction rub, ask the patient to hold his breath briefly. If the rubbing sound continues, its a pericardial friction rub because the inflamed pericardial layers continue rubbing together with each heart beat - a pleural rub stops when breathing stops.

Extra notes : Pain• Causes of Chest Pain• Cardiac pain• Angina vs Oesophageal pain• Angina vs Myocardial infarction• Characteristics of pericarditic pain• Pain caused by dissection of the thoracic aorta

Reference: Mcleods clinical examination 11th edition

Chest Pain Causes: Central vs Non-central

CentralTracheal Infection

Cardiac Acute myocardial infarction/ischaemia

Oesophageal Oesophagitis/ Rupture

Great vessels Aortic dissection

Non-centralPleural •Infection: pneumonia ,bronchiectasis ,Tb

•Malignancy: lung cancer ,mesothelioma

Pneumothorax

Pulmonary infarction

Chest wall •Malignancy: lung cancer ,mesothelioma

Persistent cough

Muscle sprains

Bornholm's disease (Coxsackie B infection)

Tietze's syndrome (costochondritis)

Heartburn is a hot, burning retrosternal discomfort which radiates upwards. When heartburn is the principal symptom, gastro-oesophageal reflux disease is the most likely diagnosis. It is often accompanied by acid reflux due to regurgitation of acid producing a sour taste in the mouth. The burning quality and upward radiation of heartburn, and its occurrence on lying flat or bending forward help to differentiate it from retrosternal chest pain originating from the heart.

Extra notes: Types of cardiac painType Cause Characteristics

Angina Coronary stenosis Precipitated by exertion, eased by rest and/or glyceryl trinitrate Characteristic distribution

Myocardial infarction Coronary occlusion Similar sites to angina, more severe, persists at rest

Pericarditis pain Pericarditis Sharp, raw or stabbing Varies with movement or breathing

Aortic Pain Aortic dissection Severe, sudden onset, radiates to the back

Reference: Mcleods clinical examination 11th edition

Angina vs Oesophageal painAngina Oesophageal painUsually precipitated by exertion Can be worsened by exertion, but often present at other times

Rapidly relieved by rest Not rapidly relieved by rest

Retrosternal and radiates to arm and jaw Retrosternal or epigastric, sometimes radiates to arm or back

Seldom wakes patient from sleep Often wakes patient from sleep

No relation to heartburn Sometimes related to heartburn

Rapidly relieved by nitrates Often relieved by nitrates

Typical duration 2-10 minutes Variable duration

Angina vs Myocardial infarctionAngina Myocardial infarctionSite: retrosternal, radiates to arm, pigastrium, neck As for angina

Precipitated by exercise or emotion Often no obvious precipitant

Relieved by rest, nitrates Not relieved by rest, nitrates

Mild/moderate severity Usually severe (may be 'silent')

No increased sympathetic activity Increased sympathetic activity

No nausea or vomiting Nausea and vomiting are common

Characteristics of pericarditic pain

Site Retrosternal, may radiate to left shoulder or back

Prodrome May be preceded by a viral illness

Onset No obvious initial precipitating factor; tends to fluctuate in intensity

Nature May be stabbing or 'raw' - 'like sandpaper'. Often described as sharp, rarely as tight or heavy

Made worse by Changes in posture, respiration

Helped by Analgesics, especially non-steroidal anti-inflammatory drugs

Accompanied by Pericardial rub

Characteristics of pain caused by dissection of the thoracic aorta

Site Often first felt between shoulder blades, and/or behind the sternumOnset Usually sudden

Nature Very severe pain, often described as 'tearing'

Relieved by No, tends to persist. Patients often restless with pain

Accompanied by Hypertension, asymmetric pulses, unexpected bradycardia, early diastolic murmur, syncope, focal neurological symptoms and signs

End of extra notes

Investigation: Pleurisy• Every patient should have a chest X-ray, but if normal, this does not

exclude a pulmonary cause of pleurisy. • A preceding history of cough, purulent sputum and pyrexia is

presumptive evidence of a pulmonary infection which may not have been severe enough to produce a radiographic abnormality, or which may have resolved before the chest X-ray was taken.

Management: Pleurisy• The primary cause of pleurisy must be treated.• NSAIDs

Pleural effusion: Case summary• 30 years old male c/o SOB of 2 weeks duration.• SOB: insidious, progressive. • A/w dry cough, Low grade evening rise fever.• H/o Loss of weight, decrease appetite and night sweats.

Pleural effusion

Source: wikipedia

A pleural effusion is an abnormal collection of fluid in the pleural space resulting from excess fluid production or decreased absorption or both.1

Ref:1. Diaz-Guzman E, Dweik RA. Diagnosis and management of pleural effusions: a practical approach. Compr Ther. 2007 Winter. 33(4):237-46.

Mechanisms of Fluid accumulation1. increased drainage of fluid into the space2. increased production of fluid by cells in the space3. decreased drainage of fluid from the space

Development of Pleural effusionThe normal pleural space contains approximately 0.1 mL/kg of fluid, representing the balance between (1) hydrostatic and oncotic forces in the visceral and parietal pleural vessels and (2) extensive lymphatic drainage. Pleural effusions result from disruption of this balance.• Altered permeability of pleural membranes (eg, inflammation, malignancy, pul embolus)• Reduction in IV oncotic pressure (eg, hypoalbuminemia due to nephrotic syn or cirrhosis)• Increased capillary hydrostatic pressure in systemic /pulmonary circulation (eg, CHF)• Reduction of pressure in the pleural space, preventing full lung expansion or "trapped

lung" (eg, extensive atelectasis, mesothelioma)• Decreased lymphatic drainage or complete blockage, including thoracic duct obstruction

or rupture (eg, malignancy, trauma)• Increased peritoneal fluid, with migration across the diaphragm via the lymphatics or

structural defect (eg, cirrhosis, peritoneal dialysis)

Types• Pleural effusion have been classically divided into transudative and exudative effusions.

Other types are empyema, Hemorrhagic pleural effusion and Chylous or chyliform effusion.

• A transudative pleural effusion occurs when alterations in the systemic factors that influence pleural fluid movement result in a pleural effusion. Examples are elevated pleural capillary pressure with heart failure, and decreased serum oncotic pressure with the nephrotic syndrome, hepatic cirrhosis.

• In contrast, exudative pleural effusions occur when the pleural surfaces themselves are altered. Inflammation of the pleura, leading to increased protein in the pleural space, is the most common cause of exudative pleural effusions.

Causes of Pleural effusionEXUDATIVE (usually unilateral)Parapneumonic effusionTuberculosisConnective tissue disordersMalignancySubphrenic abscessInfections /PancreatitisPulmonary embolism (E+T)

TRANSUDATIVE (usually bilateral )Congestive heart failureCirrhosisNephrotic syndromeConstrictive pericarditis (*)Peritoneal dialysis (hypervolemia)Hypothyroid pleural effusion(*)(pleural capillary leak)Atelectasis

CHYLOTHORAX(*)Congenital chylothoraxPost-traumatic

HEMOTHORAXBlunt traumaMalignancy

*=mostly exudative

URINOTHORAXDue to obstructive uropathy

• Meigs syndrome (benign pelvic neoplasm with associated ascites and pleural effusion)• Yellow nail syndrome (yellow nails, lymphedema, pleural effusions)• Chylothorax (acute illness with elevated triglycerides in pleural fluid)• Pseudochylothorax (chronic condition with elevated cholesterol in pleural fluid)

Drugs causing Pleural effusion• Minoxidil• Amiodarone• Beta blockers• Calcium channel blockers• Chemo (methotrexate, bleomycin, cyclophosphamide)• Ramipril• Procainamide• Hydralazine

History• A detailed medical history should be obtained from all patients presenting

with a pleural effusion, as this may help to establish the etiology. • For eg, a H/O chronic hepatitis or alcoholism with cirrhosis suggests

hepatic hydrothorax or alcohol-induced pancreatitis with effusion. • The patient should be asked about a history of cancer, even remote, as

malignant pleural effusions can develop many years after initial diagnosis.• An occupational history should also be obtained, including potential

asbestos exposure, which could predispose the patient to mesothelioma or benign asbestos-related pleural effusion.

• The patient should also be asked about medications they are taking.

• The clinical manifestations of pleural effusion are variable and often are related to the underlying disease process.

• The most commonly associated symptoms are progressive dyspnea, cough, and pleuritic chest pain.

• Pain may be mild or severe. • It is typically described as sharp or stabbing and is exacerbated with deep inspiration. • Pain may be localized to the chest wall or referred to the ipsilateral shoulder or upper abdomen because of

diaphragmatic irritation. • Pain may diminish in intensity as the pleural effusion increases in size and the inflamed pleural surfaces are no

longer in contact with each other.

Additional points• Other symptoms in association with PE may suggest the underlying

disease process. • Increasing lower extremity edema, orthopnea, and PND may all occur

with CCF.• Night sweats, fever, hemoptysis, and weight loss should suggest TB. • Hemoptysis also raises the possibility of malignancy, other

endotracheal or endobronchial pathology, or pulmonary infarction. • An acute febrile episode, purulent sputum production, and pleuritic

chest pain may occur in patients with an effusion associated with pneumonia.

Physical examination• Physical findings in pleural effusion are variable & depend on the vol of the effusion. Generally, there are

no physical findings for effusions <300 mL. With effusions >300 mL, findings may include the following:

• Asymmetrical chest expansion, with diminished expansion on the side .• Mediastinal shift away from the effusion. (> 1000 mL)

• Dullness to percussion, decreased tactile fremitus.• Diminished or inaudible breath sounds• Egophony at the most superior aspect of the pleural effusion• Pleural friction rub

Note:Displacement of the trachea and mediastinum toward the side of the effusion is an important clue to obstruction of a lobar bronchus by an endobronchial lesion, which can be due to malignancy .

DIAGNOSIS

Chest radiograph (x-ray) -able to distinguish >200ml of fluid (blunted costophrenic angles) -Chest radiographs acquired in the lateral decubitus position are more sensitive

and can pick up as little as 50 ml of fluid.Pleural fluid analysisChest ultrasound -locates small amounts or isolated loculated pockets of fluid -able to give precise position of accumulationComputed Tomography (CT) scan -Differentiates between fluid collection, lung abscess, or tumor

A posteroanterior and lateral chest radiograph of pleural effusion blunting of the posterior costophrenic angle

28Dr. Canmao xie

Workup• Thoracocentesis• Distinguish Transudate or Exudate

Normal pleural fluid has the following characteristics:• Clear • A pH of 7.60-7.64• Protein content of less than 2% (1-2 g/dL)• Fewer than 1000 (WBCs) per cubic ml• Glucose content similar to that of plasma• Lactate dehydrogenase less than 50% of plasma

Extra note• Frankly purulent fluid =empyema• A putrid odor suggests = anaerobic empyema• A milky, opalescent fluid = chylothorax (dt lymphatic obstruction by

malignancy or thoracic duct injury by trauma or surgical procedure)• Grossly bloody fluid = trauma, malignancy, postpericardiotomy

syndrome, or asbestos-related effusion.( A pleural fluid hematocrit level of >50% of the peripheral hematocrit level defines a hemothorax, which often requires tube thoracostomy)

• Black pleural fluid =infection with Aspergillus or Rizopus, malignant melanoma, non-small cell lung cancer or ruptured pancreatic pseudocyst.

Distinguishing Transudates From Exudates : Light’s criteriaThe fluid is considered an exudate if any of the following are found:1. Ratio of pleural fluid to serum protein >0.52. Ratio of pleural fluid to serum LDH >0.63. Pleural fluid LDH > 2/3rd of the upper limits of normal serum LDH

The fluid is considered a transudate if all of the above are absent.

TREATMENTTherapy should be aimed at the underlying disease.Therapeutic drainage for relief of symptoms.Transudative effusion by fluid overload as in cardiac or renal failure: diuretics & fluid managementNephrotic syndrome and cirrhosis of liver: Albumin infusionTubercular pleural effusion: Anti-tubercular drugs

Note: Pleural biopsy should be considered, only if TB or malignancy is suggested.Effusions that are chronic or recurrent and causing symptoms can be treated with pleurodesis or by intermittent drainage with an indwelling catheter.Pleurodesis is done by instilling a sclerosing agent into the pleural space to fuse the visceral and parietal pleura and eliminate the space. The most effective and commonly used sclerosing agents are talc, doxycycline, and bleomycin delivered via chest tube or thoracoscopy.

The effusion is empyema if bacteria are present on Gram staining, the pH is <7.20, glucose<40 mg/dl and LDH>1000 IU/L and there are >100,000 neutrophils/µL. ========= Chest tube drainage

End of SlidesNext lecture:

Pneumothorax and Mesothelioma

References :• http://emedicine.medscape.com/article/299959-overview• Uptodate 20.3• Davidson• Mcleods’ Examination