Basics
Description
Abnormal collection of free air or gas in the pleural space
Epidemiology
Depends on the underlying lung disease
Incidence
- Spontaneous pneumothorax
- Male > female (1.4 to 10.1:1)
- Peak incidence: 10 " 30 years
- Pneumothorax with cystic fibrosis (CF)
- For overall CF population: 3.5 " 8%
- CF patients >18 years: 16 " 20%
- Risk factors for pneumothorax:
- More severe disease
- Decreased pulmonary function (i.e., forced expiratory volume in 1 second [FEV1] <30 " 50%)
- Colonization with Pseudomonas aeruginosa, Burkholderia cepacia, or Aspergillus
Risk Factors
- Asthma
- CF
- Pneumonia
- Collagen vascular diseases
Pathophysiology
- Air can enter the pleural space via the following:
- Chest wall (i.e., penetrating trauma)
- Intrapulmonary (i.e., ruptured alveoli)
- Usually, collapse of the lung on the affected side seals the leak.
- If a ball valve mechanism ensues, however, air can accumulate in the thoracic cavity, causing the development of a tension pneumothorax (a medical emergency).
Etiology
- Spontaneous (secondary to rupture of apical blebs)
- Mechanical trauma
- Penetrating injury (i.e., knife or bullet wound)
- Blunt trauma (i.e., auto accident)
- Barotrauma
- Mechanical ventilation
- Cough (if severe enough)
- Vaginal birth
- Iatrogenic
- Central venous catheter placement
- Bronchoscopy (especially with biopsy)
- Infection: most common organisms
- Staphylococcus aureus
- Streptococcus pneumoniae
- Mycobacterium tuberculosis
- Bordetella pertussis
- Pneumocystis jiroveci
- Airway occlusion
- Mucus plugging (asthma)
- Foreign body
- Meconium aspiration
- Bleb formation (i.e., idiopathic, secondary to CF)
- Malignancy
- Catamenial
Diagnosis
History
- May be asymptomatic (pneumothorax discovered on chest film obtained for other reasons)
- Cough
- Shortness of breath
- Dyspnea
- Pleuritic chest pain that is usually sudden in onset and localized to apices (referred pain to shoulders)
- Respiratory distress
- Underlying medical problems which increases risk for pneumothorax
- Activity prior to developing symptoms that might have caused the pneumothorax:
- Heavy lifting
- Increased coughing
Physical Exam
- May be normal
- Decreased breath sounds on the affected side
- Decreased vocal fremitus
- Hyperresonance to percussion on the affected side
- Tachypnea
- Tachycardia
- Shortness of breath
- Respiratory distress
- Shifting of the cardiac point of maximal impulse away from the affected side
- Shifting of the trachea away from the affected side
- Subcutaneous emphysema
- Cyanosis
- Scratch sign (heard through the stethoscope): A loud scratching sound is heard when a finger is gently stroked over the area of the pneumothorax.
Diagnostic Tests & Interpretation
- EKG
- Diminished amplitude of the QRS voltage
- Rightward shift of the QRS axis (if left-sided pneumothorax)
Lab
- Arterial blood gas
- Po2 can frequently be decreased.
- Pco2
- Elevated with respiratory compromise
- Decreased from hyperventilation
- Pulse oximetry
- Useful for assessing oxygenation
Imaging
- Chest radiograph
- Radiolucency of the affected lung
- Lack of lung markings in the periphery of the affected lung
- Collapsed lung on the affected side
- Possible pneumomediastinum with subcutaneous emphysema
- Chest CT
- Useful for finding small pneumothoraces
- Can help distinguish a pneumothorax from a bleb or cyst
- Helpful for locating small apical blebs associated with spontaneous pneumothoraces
Diagnostic Procedures/Other
- Pitfalls:
- Not considering the diagnosis in otherwise healthy patients
- Confusing the symptoms with those of an underlying lung disease
- Inserting a needle into a cyst or bleb (can cause a tension pneumothorax with rapid respiratory compromise)
Differential Diagnosis
- Pulmonary
- Congenital lung malformations
- Cysts (i.e., bronchogenic cysts)
- Cystic adenomatoid malformation
- Congenital lobar emphysema
- Acquired emphysema
- Hyperinflation of the lung
- Postinfectious pneumatocele
- Bullae formation
- Miscellaneous
- Diaphragmatic hernia
- Infections (i.e., pulmonary abscess)
- Muscle strain
- Pleurisy (i.e., pleuritis)
- Rib fracture
Treatment
General Measures
- Stabilization of the patient
- Evacuation of the pleural air
- Should be done urgently if a tension pneumothorax is suspected
- In small asymptomatic pneumothoraces, observation of the patient is indicated.
- Treat the underlying condition predisposing for the pneumothorax:
- Antibiotics for any underlying infection
- Bronchodilators and anti-inflammatory agents for asthma attacks
- Oxygen
- Used to keep Sao2 ≥95%
- Breathing 100% oxygen
- Can speed the intrapleural air 's reabsorption into the bloodstream, hastening lung reexpansion
- Useful for treating smaller pneumothoraces, especially in neonates
Surgery/Other Procedures
- Needle thoracentesis: useful for evacuation of the pleural air in simple, uncomplicated spontaneous pneumothorax
- Chest tube drainage
- Used for evacuation of the pleural air in recurrent, persistent, or complicated pneumothoraces and cases with significant underlying lung disease
- Chest tube should be left in (usually 2 " 4 days) until
- Most air is reabsorbed
- No reaccumulation of air is seen on sealing of the chest tube
- Surgical removal of pulmonary blebs
- Blebs have a high rate of rupturing with resultant pneumothorax.
- In patients with established pneumothoraces, the blebs should be removed or oversewn to prevent reoccurrence of the pneumothorax (blebs have a high rate of reoccurrence if not repaired).
- Thoracotomy versus video-assisted thoracoscopic surgery (VATS)
- Pleurodesis
- Used to attach the lung to the intrathoracic chest wall to prevent reoccurrence of a pneumothorax
- Useful in cases of recurrent pneumothorax or if the pneumothorax is unresponsive to chest tube drainage (i.e., CF, malignancy)
- Mechanism of action: The surface of the lung becomes inflamed and adheres to the chest wall via the formation of scar tissue.
- 2 commonly used methods:
- Surgical pleurodesis:
- Mechanical abrasion of part of the lung or pleurectomy
- Advantages: very effective; low reoccurrence rate; site specific (limits affected area)
- Disadvantages: requires surgery and general anesthesia; contraindicated if patient is unstable
- Chemical pleurodesis
- Chemicals are used to cause inflammation.
- Chemicals commonly used: talc, tetracycline, minocycline, doxycycline, quinacrine
- Advantages: requires no surgery or general anesthesia
- Disadvantages: less effective than surgery; generalized inflammation (rather than site-specific; makes future thoracic surgery more difficult; painful)
Ongoing Care
Follow-up Recommendations
Symptomatic relief within seconds of the air being evacuated
Patient Monitoring
Sign to watch for: inability to remove the chest tube without reaccumulation of air (suggestive of a bronchopulmonary fistula; requires surgical exploration if no improvement in 7 " 10 days)
Prognosis
- Depends on the underlying cause of the pneumothorax
- If simple, spontaneous pneumothorax, recovery is excellent
- CF: Development of pneumothorax associated with increased morbidity and mortality (median survival after 1st pneumothorax is 4 years).
Complications
- Pain
- Hypoxia
- Respiratory distress
- Tension pneumothorax
- Hypoxia
- Hypercarbia with acidosis
- Respiratory failure
- Pneumomediastinum with subcutaneous emphysema
- Bronchopulmonary fistula
Additional Reading
- Baumann MH. Management of spontaneous pneumothorax. Clin Chest Med. 2006;27(2):369 " 381. [View Abstract]
- Briassoulis GC, Venkataraman ST, Vasilopoulos AG, et al. Air leaks from the respiratory tract in mechanically ventilated children with severe respiratory disease. Pediatr Pulmonol. 2000;29(2):127 " 134. [View Abstract]
- Dotson K, Johnson LH. Pediatric spontaneous pneumothorax. Pediatr Emerg Care. 2012;28(7):715 " 723. [View Abstract]
- Dotson K, Timm N, Gittleman M. Is spontaneous pneumothorax really a pediatric problem? A national perspective. Pediatr Emerg Care. 2012;28(4):340 " 344. [View Abstract]
- Flume PA, Strange C, Ye X, et al. Pneumothorax in cystic fibrosis. Chest. 2005;128(2):720 " 728. [View Abstract]
- Johnson NN, Toledo A, Endom EE. Pneumothorax, pneumomediastinum, and pulmonary embolism. Pediatr Clin North Am. 2010;57(6):1357 " 1383. [View Abstract]
- Noppen M. Management of primary spontaneous pneumothorax. Curr Opin Pulm Med. 2002;9(4):272 " 275. [View Abstract]
- Sahn SA, Heffner JE. Spontaneous pneumothorax. N Engl J Med. 2000;342(12):868 " 874. [View Abstract]
- Ullman EA, Donley LP, Brady WJ. Pulmonary trauma emergency department evaluation and management. Emerg Med Clin North Am. 2003;21(2):291 " 313. [View Abstract]
Codes
ICD09
- 512.89 Other pneumothorax
- 512.81 Primary spontaneous pneumothorax
- 860.0 Traumatic pneumothorax without mention of open wound into thorax
- 512.0 Spontaneous tension pneumothorax
- 512.1 Iatrogenic pneumothorax
ICD10
- J93.9 Pneumothorax, unspecified
- J93.11 Primary spontaneous pneumothorax
- S27.0XXA Traumatic pneumothorax, initial encounter
- J93.0 Spontaneous tension pneumothorax
- J93.83 Other pneumothorax
- J95.811 Postprocedural pneumothorax
SNOMED
- 36118008 Pneumothorax (disorder)
- 80423007 Spontaneous pneumothorax (disorder)
- 90070003 Traumatic pneumothorax (disorder)
- 233645004 Tension pneumothorax (disorder)
- 441536000 Iatrogenic pneumothorax (disorder)
FAQ
- Q: Can a pneumothorax reoccur?
- A: Reoccurrence depends on the underlying cause of the pneumothorax. Spontaneous pneumothorax reoccurrence rates:
- Observation alone: 20 " 50%
- If thoracentesis performed: 25 " 50%
- If chest tube drainage performed: 32 " 38%
- Overall reoccurrence rate: 16 " 52%
- Chemical pleurodesis reoccurrence rates:
- Tetracycline: 25%
- Talc: 8 " 10%
- Surgical pleurodesis reoccurrence rates:
- VATS: 13%
- Thoracotomy: 3%
- Thoracotomy with pleurectomy: 0 " 4%
- CF reoccurrence rates:
- If no drainage attempted: 68%
- Thoracentesis alone: 90%
- Chest tube drainage alone: 72%
- Chemical pleurodesis:
- Tetracycline: 42 " 86%
- Quinacrine: 12.5%
- Talc: 8%
- Surgical pleurodesis: thoracotomy with pleurectomy: 0 " 4%