9/24- Pleural & Mediastinal Disease Flashcards
(54 cards)
1
Q
What are the parietal and visceral pleura?
- Blood supply
A
Parietal pleura
- Systemic circulation
- Adjacent to chest wall
Visceral pleura
- Bronchial circulation
- Adjacent to lung
2
Q
How much fluid is normally in the pleural space?
A
Normal ~15 mL
3
Q
What causes increased pleural fluid formation? (broad mechanisms and examples)
A
Increased pleural fluid formation
- Hydrostatic changes: transudative
- CHF (s)
- Atelectasis
- Oncotic changes: transudative (s)
- Altered pleura with increased permeability: exudative (l)
Decreased lymphatic drainage: exudative (l)
Combination of above
(s) = systemic factor; treat systemic condition
(l) = local factor; more serious
4
Q
What are the symptoms and signs of pleural effusion?
A
- Shortness of breath
- Sudden onset if cause is air
- More slow/progressive if due to CHF transudate
- Cough
- Less common
- Pleuritic chest pain
- more early; not so much later when pleura is spread wide apart by large effusion
- Decreased breath sounds
- Dullness to percussion
- Decreased tactile fremitus
- Distinguishes this from pneumonia
- Decreased chest wall expansion
- Tracheal shift (massive effusions)
5
Q
How to distinguish between pleural effusion and pneumonia on physical exam?
A
Tactile fremitus
- Decreased breath sounds in pleural effusion
6
Q
What is seen in radiology of pleural effusion?
A
- Blunting of costophrenic angle on PA CXR (at 100 mL)
- Larger amts: characteristic lower lung field homogeneous density that forms a concave meniscus
- Lateral decubitus film: fluid will “layer” if in significant amount
7
Q
What is seen here?
A
Pleural effusion
- Fluid “layers” and somewhat clears lung field
8
Q
What is seen here?
A
Large effusion- concave mensicus and shift of mediastinum to the right
9
Q
When is it safe to do a thoracentesis (how much pleural fluid)?
A
If you can see ~1 cm of layering
10
Q
Describe thoracentesis
A
Removal of pleural fluid transthoracically to diagnosis etiology of effusion and/or treat (remove fluid to reduce symptoms)
- Ultrasound-guided
11
Q
What is seen here?
A
Can see diaphragm and overlying fluid (and a little collapsed lung)
12
Q
What are complications of thoracentesis?
A
- Pneumothorax (11%, 2% require chest tube; down to 3% know with ultrasound guidance)
- Vasovagal reaction
- Infection (2% of pleural infections)
- Hemothorax
- Splenic/hepatic laceration
- Seeding of tumor (mesothelioma)
- Adverse RX to local anesthesia
- HIV/Hepatitis B (like any needle procedure)
- Re-expansion pulmonary edema
- Depends on rapidity [and a little quantity] of fluid removal due to induced negative P in lung
- Only remove 1-2L at a time, max
- Can measure pleural pressure (nl ~ 5); with pleural effusion P will be 0 -> (+). Keep drawing fluid until too negative (~ - 20)
13
Q
Should needle be entered right above the lower rib or right below the upper rib?
A
Just above lower rib
- Vascular bundle located just under ribs, so avoid that
14
Q
What is seen here?
A
Patient with large pleural effusion (see meniscus sign on left; right lung)
15
Q
Same pt following chest tube for fluid removal of his pleural effusion. What is this?
A
Re-expansion pulmonary edema following rapid removal of pleural effusion fluid
16
Q
What is the first decision point in evaluation of effusions?
- How is this done/what criteria?
A
Transudative vs. Exudative effusion
- Based on the results of evaluation of pleural fluid
- Differentiation based on Light’s criteria
17
Q
What is Light’s criteria?
A
Exudate has at least 1 criteria, a transudate has none:
- Pleural/serum protein > 0.5
- Pleural/serum LDH > 0.6
- (pleural) LDH > 2/3 upper limit
If you can only do 1 test, want LDH (determines 2 criteria)
18
Q
What are some causes of transudative effusions?
A
- Congestive heart failure
- Cirrhosis
- Nephrotic syndrome
- Ascites
- Peritoneal dialysis
- Hypoalbuminemia
19
Q
What are some causes of exudative effusions?
A
- Infections (i.e., parapneumonic, TB)
- Malignant disorders(lung CA, mets, mesothelioma)
- Collagen vascular diseases
- Pulmonary embolism
- Gastrointestinal disease
- Pancreatitis and pancreatic pseudocyst (high amylase)
- Esophageal rupture (high amylase)
- Abdominal or retroperitoneal abscess
20
Q
Are transudative or exudative effusions more common?
A
Transudative
- Due to commonality of CHF (no.1)
21
Q
What are the most common causes of effusions (either transudative or exudative)?
A
- CHF
- Infections (parapneumonic)
- Primary lung malignancy
22
Q
What causes problems with post coronary artery bypass graft surgery?
A
If exudative fluid sits there for a long while, visceral pleura thickened and won’t recover even with fluid recovery
- “Trap lung”
- Have to peel visceral pleura off lung
23
Q
Which type of pleural effusion requires further evaluation?
- Examples of further studies
- When to do a pleural biopsy
A
Exudative
- Cultures, gram stain if you think infectious
- Cytology if you think cancer
- Consider pleural biopsy for undiagnosed exudates after 2-3 thoracentesis attempts
- No further pleural studies are required in transudative (consider evaluation for underlying processes)
24
Q
If you get exudate from pleural effusion, what main etiologies are you worried about?
- Neutrophil predominance?
A
Worried about:
- Cancer
- TB
Neutrophil: bacterial infection
25
What is a complicated parapneumonic effusion?
- Associations
- Indications
Associated w/ pulmonary infection, do not resolve without intervention
26
What are signs of complicated parapneumonic effusion (indications for possible chest tube drainage and possible thrombolytic therapy/thoracoscopy)?
- Loculated
- Positive gram stain/culture
- pH under 7.2
- Low glucose: \< 60 MG/DL (especially \< 40 MG/DL)
- pH between 7.0 and 7.2 and high LDH: \> 1000
- Thick Pus
27
What is seen here?
Complicated parapneumonic effusion:
- Loculated pleural effusion
- Thickened pleura
28
What are characteristics of a Tubercuous Effusion?
_Early-small effusion_
- PMN’s
- Culture positivity higher
_Later-larger_
- 90% lymphocytes
- Positive culture less common PPD negative in 30%
_TB markers in fluid:_
- Adenosine deaminase
- Interferon gamma, or
- PCR (polymerase chain reaction) for tuberculous DNA Undiagnosed serous, lymphocytic exudate with +PPD requires treatment
29
What are charcteristics of pleural effusions due to malignancy ?
- What may predict prognosis
- 10% are transudates, not related to pleural involvement
- Effusion may be bloody
- Lymphocyte predominant effusion
- pH under 7.30 (30%) and low glucose predicts a decreased survival time
- Diagnosis made by cytology
30
What is seen here?
Pneumothorax
31
What are classifications/causes of pneumothorax?
_Spontaneous_
- Primary
- Secondary
* Underlying lung dz (e.g. COPD with large bullae)
_Traumatic_
- Iatrogenic
- Non-iatrogenic
32
Clinical signs of pneumothorax?
- Dyspnea
- Cough
- Pleuritic chest pain
- Increased pressures on mechanical ventilation
- Decreased chest wall motion
- Hyper-resonance to percussion
- NO breath sounds in that area (really significant)
- Decreased vocal resonance
33
Describe primary spontaneous pneumothorax
- Cause
- Associations
- Clinical phenotype
- Treatment
- “Idiopathic” pneumothorax
- Usually related to rupture of **apical pleural “blebs”**
_Clinical:_
- Usually **20-30** years of age
- Tall, thin
- Mainly **smokers**
- **Males** \> females (5x)
_Presentation:_
- Acute onset of severe unilateral chest pain with dyspnea
_Treatment:_
- Small, non-enlarging pneumothorax: observe
- Large or enlarging: place chest tube
34
What is the prognosis of primary pneumothorax (PTX)?
- 20-30% recur within 5 years
- Those with 1st PTX are more likely to have subsequent PTX
_To prevent recurrence:_
- **Thoracotomy** with over **sewing of apical blebs** if present and pleural abrasion
- Versus initial attempt at **chest tube and chemical pleurodesis** (irritate pleura and cause adhesion... to?)
35
Describe secondary spontaneous pneumothorax
- Associations
- Symptoms/presentation
- Diagnostic method
- Most common with underlying COPD (emphysema)
- Can be difficult to recognize clinically
- Suddenly worsening dyspnea and respiratory status with acute chest pain
- CXR diagnostic
36
What is a tension pneumothorax?
- Cause
- Signs/symptoms
- Trachea movement?
- Treatment
- Most often occurs during mechanical ventilation or resuscitation
_Signs/symptoms:_
- Cyanosis and hypotension
- Absence of breath sounds on affected side
- Shift of trachea away from affected side
_Treat:_ large bore catheter to rapidly remove gas followed by chest tube placement
37
How can the mediastinum be divided?
- **Anterior**-lying forward and superior to the heart shadow and extending to the anterior vertebrae
- **Middle**-triangular shaped, extending from the heart shadow to the anterior vertebral border
- **Posterior**-occupies the space within the margins of the vertebra
38
What are contents of the anterior mediastinum?
- Thymus gland
- Sub-sternal extensions of thyroid and parathyroid glands
- Aortic arch and major branches
- Innominate veins
- Lymphatic vessels and lymph nodes
39
What are contents of the posterior mediastinal compartment?
- Esophagus
- Thoracic duct
- Descending aorta
- Lymph nodes
- Azygos and hemiazygos veins
- Vagus nerves and sympathetic chains
40
What are contents of the middle mediastinal compartment?
- Heart and pericardium
- Trachea and main bronchi
- Hila and LNs
- Phrenic and vagus nerves
41
Possible masses of mediastinum (for all compartments)? [from picture; skim]
_Posterior_
- Neurogenic tumors/cysts
- Meningocele
- Lymphoma
- Esophageal disease: neoplasm, diverticula, megesophagus, Bochdalek hernia
- Aneurysm
_Anterior:_
- Thymomas
- Substernal thyroid
- Parathyroid lesions
- Germinal cell neoplasms
- Lymphomas
_Middle_
- Bronchogenic cysts
- Pleuropericardial cysts
- Lymphadenopathy: sarcoidosis, malignancy, granulomatous disease
- Aneurysms
- Morgagni hernias
42
What are symptoms of mediastinal masses?
- **Cough**: compression of the trachea or bronchi
- **Chest pain**: traction on tissue, dull, constant, exacerbated when lying down
- **Dysphagia** (difficulty swallowing), seen with posterior mediastinal masses
_Symptoms secondary to nerve compression/invasion_
- **Hoarseness**: recurrent laryngeal nerve
- **Horner’s** syndrome: (ipsilateral ptosis, miosis, anhydrosis), secondary to stellate ganglion involvement
- **Diaphragmatic** **paralysis**: secondary to phrenic nerve involvement
43
What are symptoms of medisatinal masses?
"Terrible Ts"
- Thymoma
- Teratoma
- Thyroid
- Tumor, especially lymphoma
44
What is the most common mass in the anterior compartment?
Thymoma
45
Describe thymoma
- Pt age
- Symptoms
- Pathology
- Poor prognostic signs
- Associations
- **40-60** yrs
- **2/3** are **asymptomatic**
_Pathology_: most are **benign** and if fully **encapsulated** without evidence of invasion, prognosis is good
_Poor prognosis:_ **Invasion** and an associated **systemic** syndrome
_Associated syndromes:_
- **40-70%** of patient have at least laboratory evidence of a “**parathymic**” syndrome"
- **Myasthenia gravis** (10-50%) most common
46
What is seen here?
Thymoma
- No retrosternal air space
47
What is the most common germ cell tumor?
- Characteristics
- Pt age
- Malignant vs. benign
- Treatment
Teratoma
- Masses are made up of tissue foreign to the area and are predominately of ectodermal derivatives (may contain hair, teeth, etc.)
- Tumor may be **cystic or solid**
- **80%** are **benign**
- Usually occurs in **young adults**
- Treatment: surgical **resection**
48
What are common masses in the middle compartment?
- Lymphoma (10-20%)
* 1/3 are Hodgkin's
* Usually in young adults
* 2nd most common mediastinal mass in kids
- Developmental cysts (up to 20%)
- Granulomatous diseases: TB, Sarcoidosis
- Vascular masses (aneurysms)
- Diaphragmatic hernia: herniation of fat or abdominal contents
49
What is seen here?
Bronchogenic Cyst
50
What are common masses in the posterior compartment?
- Neurogenic tumors (most common)
- Esophageal lesions: cancer, diverticula, megaesophagus
- Diaphragmatic hernia
- Aneurysms
- Lymphoma
51
Characteristics neurogenic tumors
- Adult vs. kid
- Symptoms
- Origin
- Most common mass of the posterior mediastinum
* 20% of adult
* 40% of masses in children
_Symptoms:_
- Usually asymptomatic/benign in adults
- Children 50% are symptomatic and malignant
_Derivation:_
- Peripheral nerves (ex. neurofibroma)
- Sympathetic ganglia (ganglioneuroma)
- Paraganglionic tissue (pheochromocytoma)
52
What are some causes of pneumomediastinum?
- Signs/symptoms
- **Trauma**
- **Esophageal perforation**
- **Infection** (gas producing)
- **Alveolar Rupture** (Valsalva, Labor, Mechanical ventilation)
- **Severe substenal chest pain** +/- radiation into the neck and arms
- Possible **Hamman’s sign** (crunching or clicking noise synchronous with heartbeat)-best heard in left lateral decubitus position
53
Describe acute mediastinitis?
- Causes
- Symptoms
- CXR results
_Causes_
- **Infection** within the mediastinum
- Include **iatrogenic** (perforation of trachea, or esophagus; following sternotomy for cardiac surgery)
- **Direct extension**
_Classic symptoms:_
- High fever
- Chest pain
- Hamman’s sign (auscultated mediastinal “crunch” that coincides with cardiac systole)
- Possible evidence of sternal infection
_Chest x-ray;_ mediastinal widening and air fluid levels
54
Describe chronic/fibrosing mediastinitis
- Causes
Secondary to chronic inflammation and eventual fibrosis:
- Histoplasmosis
- TB
- Fungal disease
- Drugs (methysergide)
- Radiation
