Pleural Space Disorders

Question 1

A serous membrane called _____ lines the outer surfaces of the lungs and the adjacent internal thoracic wall

Answer 1

Pleura

Question 2

Pleura is formed from a
simple squamous
epithelium called:
_____

Answer 2

Mesothelium

Question 3

Pleuritis

Answer 3

● Pleuritis is inflammation of the
pleural linings of the lung.
○ Also known as “Pleurisy”
● This is a painful condition because
the acute inflammation causes
irritation of the pain fibers in the
Parietal Pleura.

Question 4

Causes of Pleuritis

Answer 4

○ Asbestosis
○ Drugs:
■ Amiodarone
■ Methotrexate
■ Nitrofurantoin
■ Valproic Acid
■ Propylthiouracil
■ Isotretinoin
■ Acyclovir
■ Simvastatin
○ Pulmonary Embolism
○ Myocardial Infarction
○ Pericarditis
○ Pleural Effusion
○ Viral Infection (very common)
○ Bacterial Infection
○ Fungal Infection
○ Malignancy
○ Lupus (SLE)
○ Rheumatoid Arthritis

Question 5

Pleuritis Pathophysiology

Answer 5

○ This causes friction to develop at
that localized site of inflammation.
○ Pleuritis is usually considered a
symptom of an underlying condition,
rather than a condition in and of
itself

Question 6

Pleuritis clinical presentation

Answer 6

○ With each deep breath, sneeze, or cough, the two layers of pleura grind against each other, causing a sharp, localized, fleeting pain
○ The patient can often point to a specific epicenter
○ If the central portion of the diaphragmatic parietal pleura is irritated, pain may be referred to ipsilateral shoulder.
○ Most commonly there are symptoms of the underlying condition, but pleurisy may be the presenting symptom.

Question 7

Pleuritis diagnosis

Answer 7

○ Accurate diagnosis of the cause of pleurisy requires that the clinician take a thorough history, thorough physical exam, and do appropriate diagnostic tests
○ A pleural friction rub is often auscultated directly over the area of pleural inflammation

Question 8

Pleuritis treatment

Answer 8

○ Treatment of pleurisy is centered around treating the underlying condition
■ For example, treat the MI, PE, pneumothorax, etc.
■ Because pleurisy is most often a symptom of another condition, it is important to not miss the diagnosis of the
other condition (could be life-threatening!).
○ The pleurisy itself can be treated with NSAIDs (Indomethacin is the most studied/effective)

Question 9

Pneumothorax

Answer 9

● Because of the muscular tone and
contraction of the diaphragm and
external intercostals, there is normally negative pressure in the pleural space.
○ Negative pressure in a potential space
● A pneumothorax occurs when a
situation arises that allows air to enter this normally airless space.

Question 10

Pneumothorax pathophysiology

Answer 10

○ Air can be introduced by a break in a
pleural membrane
○ Chest wall trauma or iatrogenic means
can lead to a break in the parietal
pleura.
○ Rupture of a bleb, bulla, or necrotic
adjacent lung can lead to a break in
the visceral pleura.
○ Sometimes it occurs without a known
reason (AKA Spontaneous Pneumothorax).
■ More common: Tall, thin, young adult males

Question 11

Tall, thin, young adult males are more likely to get ____

Answer 11

a pneumothroax

Question 12

Pneumothorax pathophysiology

Answer 12

○ If the pneumothorax becomes large
enough, the increasing pressure in the
pleural space causes contralateral
displacement of the mediastinum
■ Deviated trachea
■ Acute cardiopulmonary failure
○ This is called a Tension
Pneumothorax, and presents with
acute respiratory and hemodynamic
compromise

Question 13

Tension pneumothorax

Answer 13

contralateral displacement of the mediastinum due to increased pressure in the pleural space from a pneumothorax
■ Deviated trachea
■ Acute cardiopulmonary failure

Question 14

Pathophysiology of tension pneumothorax

Answer 14

○ Tension Pneumothorax is most
commonly secondary to a “sucking chest wound” or pulmonary laceration.
○ Air is pulled into the chest during
inspiration, but is not allowed to leave on expiration.

Question 15

Clinical Presentation of a pneumothorax

Answer 15

○ Although a small pneumothorax may be asymptomatic,
classic presentation includes:
■ Ipsilateral chest pain
■ Dyspnea

Question 16

PE findings of pneumothorax

Answer 16

findings depend on the size of the
pneumothorax, but may include:
■ Lack of ipsilateral chest expansion
■ Decreased tactile fremitus
■ Hyperresonance (or tympany)
■ Diminished or absent breath sounds

Question 17

Diagnosis of a pneumothorax

Answer 17

○ The pathognomonic finding is presence of pleural air on a Chest X-ray
■ Look very closely for the visceral line!
○ If the size of the pneumothorax is significant, an ABG may reveal hypoxemia

Question 18

Pneumothorax treatment

Answer 18

○ If the case is a Tension Pneumo,
initial treatment is placement of a
large bore catheter needle in the
2nd intercostal space
■ “Needle Decompression”
■ Followed by Chest Tube placement
○ A small pneumothorax may resolve
spontaneously.
○ Larger pneumothoraces should be treated
with a Chest Tube Thoracostomy

Question 19

What to do once a chest tube is placed

Answer 19

○ Once the chest tube is placed, it is hooked up to a water-seal
drainage system.
○ Chest X-rays should be performed
daily in the hospital

Question 20

Pleural Effusion

Answer 20

● The accumulation of abnormal amounts of fluid within the pleural cavity secondary to disease
● Normally, fluid is constantly moved into
the pleural space from the parietal pleural
capillaries at a rate of 15-20 mL per day

Question 21

Pleural Effusion: 4 main types

Answer 21

■ Exudate- Secondary to an inflammatory process that results in “leaky capillaries” and protein-rich effusion
■ Transudate- Secondary to increased hydrostatic or decreased oncotic pressure with “intact capillaries” & low-protein effusion
■ Empyema- Collection of pus in the pleural space secondary to a significant bacterial infection
■ Hemothorax- Collection of blood in the pleural space secondary to trauma or malignancy

Question 22

Risk factors for empyema

Answer 22

■ Pneumonia
■ Trauma
■ Surgery
■ Lung abscess

Question 23

Pleural Effusion clinical presentation

Answer 23

○ With large or bilateral pleural effusions, symptoms will
commonly include:
■ Dyspnea
■ Cough
■ Pleuritic chest pain
○ Percussion over the area may reveal dullness or flatness.
○ Decreased tactile fremitus and impaired diaphragmatic
excursion on the affected side are possible.

Question 24

Pleural Effusion diagnosis:

Answer 24

○ Radiographic findings include blunting
of the costophrenic angle
○ Thoracentesis is the gold standard for diagnosis

Question 25

_____ helps determine if a pleural effusion is transudative vs exudative.

Answer 25

Light’s Criteria

Question 26

Interpreting Thoracentesis Results

Answer 26

○ Grossly purulent fluid signifies empyema
○ Fluid that is grossly bloody may signify a
hemothorax is the diagnosis
○ Differentiation between exudative and
transudative is a little more complex as the
gross appearance may be similar in nature
○ Thoracentesis samples should be sent for measurement of protein, glucose, lactate dehydrogenase, and WBC counts

Question 27

Pleural Effusion Treatment

Answer 27

○ Thoracentesis is often therapeutic in addition to diagnostic, especially if significant dyspnea is present.
○ Once the cause of the pleural effusion is established, treatment is focused on the underlying condition.
○ Empyema or persistent effusion may require placement of a chest tube for continued drainage