Pleural Effusions and Pneumothorax презентация

Pleural Effusions introduction
The movement of fluid across the pleural membranes is complicated but in general is governed by Starling's law of capillary exchange
5 to 10 L of fluid transgress the pleural space over a 24-hour period
Under physiologic conditions, most pleural fluid reabsorption is through lymphatics of the parietal pleura

Pleural Effusions introduction
imbalance of accumulation and absorption of pleural fluid will lead to the development of a pleural effusion:
1. Increased hydrostatic pressure
2. Increased negative intrapleural pressure
3. Increased capillary permeability
4. Decreased plasma oncotic pressure
5. Decreased or interrupted lymphatic drainage

Pleural Effusions introduction
About 300 mL of fluid is required for the development of costophrenic angle blunting seen on an upright chest radiograph.
At least 500 mL of effusion is necessary for detection on clinical examination.

Transudative Vs. Exudative Effusions
Criteria:
1. Pleural fluid protein/serum protein greater than 0.5 2. Pleural fluid LDH/serum LDH greater than 0.6
3. Pleural fluid LDH 1.67 times normal serum
These criteria misidentify ~25% of transudates as exudates
A transudative pleural effusion occurs when systemic factors that influence the formation and absorption of pleural fluid are altered.
An exudative pleural effusion occurs when local factors that influence the formation and absorption of pleural fluid are altered

Diagnostic Approach
The leading causes of transudative pleural effusions in the United States are left-ventricular failure and cirrhosis
The leading causes of exudative pleural effusions are bacterial pneumonia, malignancy, viral infection, and pulmonary embolism.

Pleural fluid analysis
Gross appearance (pus- Empyema, black- Aspergillus, green- Biliothorax, white- Chylothorax)
Very high LDH- empyema, rheumatoid pleurisy, malignancy
High triglyceride- Chylothorax
Low glucose- Rheumatoid pleurisy, parapneumonic effusion or empyema, Malignant effusion, Tuberculous pleurisy, Lupus pleuritis, Esophageal rupture
Low pH- parapneumonic effusion or empyema, Malignant effusion
High amylase- Acute pancreatitis, Chronic pancreatic pleural effusion, Esophageal rupture, Malignancy
adenosine deaminase (ADA), interferon gamma - Tuberculous pleurisy
Lymphocytosis- tuberculous pleurisy, lymphoma, sarcoidosis, chronic rheumatoid pleurisy

Effusion Due to Heart Failure
A diagnostic thoracentesis should be performed if the effusions are not bilateral and comparable in size, if the patient is febrile, if the patient has pleuritic chest pain or if the effusion persists despite therapy
A pleural fluid N-terminal pro-brain natriuretic peptide (NT-proBNP) >1500 pg/mL is virtually diagnostic of an effusion secondary to congestive heart failure

Hepatic Hydrothorax
Pleural effusions occur in ~5% of patients with cirrhosis and ascites
effusion is usually right-sided

Parapneumonic Effusion
Parapneumonic effusions are associated with bacterial pneumonia, lung abscess, or bronchiectasis and are probably the most common cause of exudative pleural effusion
Empyema refers to a grossly purulent effusion

Parapneumonic Effusion
Patients with aerobic bacterial pneumonia and pleural effusion present with an acute febrile illness consisting of chest pain, sputum production, and leukocytosis
Patients with anaerobic infections present with a subacute illness
If the free fluid separates the lung from the chest wall by >10 mm, a therapeutic thoracentesis should be performed

Uncomplicated Vs. Complicated parapneumonic effusion
An uncomplicated parapneumonic effusion has "exudative" chemistries, normal pH and glucose, and negative cultures
A complicated parapneumonic effusion typically has "exudative" chemistries, a low pleural pH (pH <7.20), a low glucose, and is often loculated

Indication for pleural drainage
Loculated pleural fluid
Pleural fluid pH <7.20
Pleural fluid glucose <3.3 mmol/L (<60 mg/dL)
Positive Gram stain or culture of the pleural fluid
Presence of gross pus in the pleural space

Before and after driange

Treatment of parapneumonic effusion
An empiric, broad spectrum antibiotic that includes coverage for anaerobic organisms
In patients with an uncomplicated parapneumonic effusion that is small to moderate in size, free flowing, and has a pH of 7.20 or greater there is no indication for drainage
In patients with a large, loculated, or complicated parapneumonic effusion there is indication for prompt drainage of any remaining pleural fluid by chest tube.

Effusion Secondary to Malignancy
Malignant pleural effusions secondary to metastatic disease are the second most common type of exudative pleural effusion
The three tumors that cause ~75% of all malignant pleural effusions are lung carcinoma, breast carcinoma, and lymphoma

Effusion Secondary to Malignancy
The diagnosis usually is made via cytology of the pleural fluid
If the initial cytologic examination is negative, thoracoscopy is the best next procedure if malignancy is strongly suspected

Treatment of Malignant pleural effusion
If the patient's lifestyle is compromised by dyspnea and if the dyspnea is relieved with a therapeutic thoracentesis, one of the following procedures should be considered:
therapeutic thoracentesis
insertion of a small indwelling catheter
pleurodesis

Pneumothorax introduction
Pneumothorax is the accumulation of air within the pleural space
Pneumothorax can be spontaneous or occur secondary to a traumatic, surgical, therapeutic, or disease-related event
pneumothorax compresses lung tissue and reduces pulmonary compliance, ventilatory volumes, and diffusing capacity
If air enters the pleural space repeatedly and is unable to escape, positive pressure will develop in the pleural space. This situation is called a tension pneumothorax

Pneumothorax introduction
Patients with pneumothorax most commonly present with chest pain (sharp and pleuritic) and dyspnea
Characteristic physical findings include:
Hyperresonance on percussion
Breath sounds are diminished to absent.
Subcutaneous emphysema may be palpated

diagnosis
A pneumothorax usually is seen on the standard posteroanterior chest radiograph

Hydropneumothorax

Classifications of Pneumothorax
Spontaneous
Primary
Secondary
Traumatic
Iatrogenic
Esophageal perforation

primary spontaneous pneumothorax
A primary spontaneous pneumothorax occurs in the absence of underlying lung disease
Patients are often tall, thin and smoker men from 25 to 40 years of age (rare after age 40)
Risk factor include: smoking, family history, Marfan syndrome, homocystinuria, and thoracic endometriosis
Primary spontaneous pneumothoraxes are usually due to rupture of apical pleural blebs (>85%)
25-50% of patients with a first time spontaneous pneumothorax will have a recurrence (most recurrences occurring within the first year )

Treatment of primary spontaneous pneumothorax
Small pneumothoraces (<20%, ≤2 to 3 cm between the lung and chest wall on a chest radiograph) that are stable may be monitored if the patient has few symptoms. An uncomplicated pneumothorax reabsorbs at a rate of about 1% per day.
Indications for intervention include progressive pneumothorax, delayed pulmonary expansion, or development of symptoms.

Treatment of primary spontaneous pneumothorax
Moderate (20%-40%) and large (>40%) pneumothoraces nearly always are associated with persistent symptoms that cause physical limitations and require intervention
Simple needle aspiration of a pneumothorax may relieve symptoms and can promote quicker lung re-expansion
Tube thoracostomy (chest tube insertion) and underwater seal drainage are the mainstays of treatment for spontaneous pneumothorax.
The classic location for chest tube insertion is through the fourth, fifth, or sixth intercostal space in the mid to anterior axillary line.

Treatment of primary spontaneous pneumothorax
Complications of chest tube insertion for pneumothorax are infrequent but include laceration of an intercostal vessel, laceration of the lung, intrapulmonary or extrathoracic placement of the chest tube, and infection.
When an air leak persist for more than 72 hours or the lung not completely re-expand, surgical intervention is warranted

Indication for Surgical intervention in spontaneous pneumothorax
Air leak that persist for more than 72 hours or when the lung not completely re-expand
Bilateral simultaneous pneumothoraces
Complete (100%) pneumothorax
Pneumothorax associated with tension or borderline cardiopulmonary reserve
Pneumothorax in patients in high-risk professions or activities
A recurrence pneumothorax

Surgical intervention for spontaneous pneumothorax
Apical blebs are resected. The parietal pleura over the apex of the hemithorax can be removed (pleurectomy), abraded (mechanical pleurodesis), or treated with talc or tetracycline-like agents (chemical pleurodesis or poudrage).
The recurrence rate of these procedures, performed open or closed, is less than 5%

Secondary spontaneous pneumothorax
Most secondary pneumothoraxes are due to chronic obstructive pulmonary disease
Pneumothorax in patients with lung disease is more life-threatening than it is in normal individuals because of the lack of pulmonary reserve in these patients.
Treatment of secondary pneumothorax is very similar to PSP but most of the patients with secondary pneumothorax should be treated with tube thoracostomy.

Preventing recurrence
smoking cessation
VATS pleurodesis- The rate of recurrent pneumothorax is less than 5 percent after VATS with bleb/bullae resection and pleurodesis
Chemical pleurodesis- decreases the recurrence rate for pneumothorax to 15-25%

Traumatic pneumothoraxes
Traumatic pneumothoraxes can result from both penetrating and blunt chest trauma
Some times when a hemopneumothorax is present, one chest tube should be placed in the superior part of the hemithorax to evacuate the air and another should be placed in the inferior part of the hemithorax to remove the blood.

Traumatic pneumothoraxes

Iatrogenic pneumothorax
Iatrogenic pneumothorax is a type of traumatic pneumothorax that is becoming more common. The leading causes are transthoracic needle aspiration, thoracentesis, and the insertion of central intravenous catheters.

tension pneumothorax
hemodynamic collapse (decreased venous return to the heart and reduced cardiac output)
severe respiratory compromise
compression or collapse of the entire lung
shifting of the mediastinum and heart away from the pneumothorax

Diagnosis of tension pneumothorax
The diagnosis is made by physical examination:
An enlarged hemithorax with no breath sounds.
Hyperresonance to percussion
Shift of the mediastinum to the contralateral side
Low blood pressure