Pneumothorax – Quick Consult
Last Updated / Reviewed: 4/5/2021

Key History
Key Physical Exam
Risk Factors for Pneumothorax
Differential Diagnosis
Diagnostic Testing
Clinical Risk and Safety Pearls


Pneumothorax Collection of gas in the pleural space resulting in collapse of lung on the affected side
Primary Spontaneous Pneumothorax (PSP) Pneumothorax that occurs without a precipitating event in a person who has no known underlying lung disease. (Most will end up having unrecognized lung disease.)
Secondary or Complicated Spontaneous Pneumothorax Occurs as a complication of underlying lung disease
Tension Pneumothorax A life threatening condition compromising cardiopulmonary function that requires immediate treatment, characterized by tachycardia, hypotension, and cyanosis. See separate topic: Tension pneumothorax

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Key History

  • Sudden onset dyspnea
  • Sudden onset pleuritic chest pain
  • May occur at rest or with exertion (primary and secondary respectively)
  • May be asymptomatic
  • Referred pain to shoulder
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Key Physical Exam

  • Findings on the affected side:
    • Diminished breath sounds
    • Hyperresonant percussion
    • Decreased excursion
  • Subcutaneous emphysema
  • Hypoxemia
  • Tachypnea
  • Tachycardia
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Risk Factors for Pneumothorax

  • Acute endometriosis
  • Central line placement
  • Ehlers-Danlos
  • Family history
  • Homocystinuria
  • Liver biopsy
  • Male to female ratio – 6:1
  • Marfan’s Syndrome
  • Rapid altitude changes – diving, flying without pressurization
  • Smoker to non-smoker ratio – 20:1
  • Thoracentesis
  • Trauma
  • Pulmonary disease:
    • Adult respiratory distress syndrome
    • Asthma
    • COPD
    • Cystic fibrosis
    • Lung abscess
    • PCP
    • Pulmonary fibrosis
    • Sarcoidosis
    • TB
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Differential Diagnosis

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Diagnostic Testing

Text / literature information and recommendations include:
  • Chest x-ray:
    • Radiographic Features — The main radiologic feature of a pneumothorax is a white visceral pleural line, which is either straight or convex towards the chest wall, separated from the parietal pleura by an avascular collection of gas. No pulmonary vessels are visible beyond the visceral pleural edge.
    • Upright chest radiographs — In upright patients, the accumulation of gas occurs primarily in an apicolateral location. As little as 50 mL of pleural gas can be visible. A lateral width of 1 cm corresponds to about a 10 percent pneumothorax. The size of a pneumothorax is accounted for by the collapsed lung and, to a greater degree, by the expanding chest cage. Despite a considerable loss of volume, the collapsed lung preserves its transradiancy because of hypoxic vasoconstriction that diminishes its blood flow.
    • Inspiratory films are recommended as the initial examination of choice for pneumothorax detection.
    • Lateral Decubitus view – a small pneumothorax can be more easily detected in the lateral decubitus view. In this position, as little as 5 mL of pleural gas is visible on the non-dependent side.
    • Tension pneumothorax — Tension pneumothorax shows a distinct shift of the mediastinum to the contralateral side and flattening or inversion of the ipsilateral hemidiaphragm. Should be treated immediately. Take care to differentiate the pleural line from artifact.
  • CT is useful in difficult cases, for example, patients with emphysema as well as in critically ill patients who cannot tolerate upright or decubitus films. CT is more sensitive than CXR.
  • Ultrasound is being used as well to aid in diagnosis, especially in trauma cases.
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Clinical Risk and Safety Pearls

  • 5 mL of air can be seen on a lateral decubitus view.
  • 50 mL of air can be seen on an upright CXR.
  • 500 mL of air must be present to be seen on a supine CXR.
  • Tension pneumothorax shifts the mediastinum to the opposite side.
  • Catamenial pneumothorax is a pneumothorax associated with menstruation. Seen in women with pelvic endometriosis; rarely seen in women ages 30-50 years. Typically affects the right lung within 72 hours of the onset of menses. Thought to be related to endometriosis involving the pleura
  • Pregnancy: Pneumothorax is a rare complication of labor and delivery and should be suspected in the pregnant or post partum patient with dyspnea and chest pain (also consider PE).
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Common text / literature recommendations include:

  • Supplemental oxygen
  • Pneumothorax treatment recommendations

  • Small Spontaneous
    Clinically stable with mild symptoms:
    • various definitions of “small” exist:
      • less than 15% = less than 1 cm wide confined to upper third of chest
      • less than 25% of apex down = less than 4 cm apically and less than 1 cm laterally
      • less than or equal to 3 cm between lung and chest wall
    • treatment is: Observation, reabsorption rate of 1 % per day or usually 3 – 4 days. May discharge home if asymptomatic. Consider repeat CXR in 6 hours, if no increase in size may d/c home
    Larger Pneumothorax Clinically stable:
    • Needle aspiration if less than 50% or tube thoracostomy if greater than 50%
    Larger Pneumothorax Clinically unstable:
    • Chest tube thoracostomy. Needle decompression may be performed if chest tube insertion is delayed
    Secondary Pneumothorax Typically requires tube thoracostomy although some success has been had with observation if it is small.
    Admit all patients with chest tubes.
    It is prudent to admit patients with secondary pneumothorax as they likely have a diminished pulmonary reserve.

    A patient with a small pneumothorax with mild symptoms who is stable may be discharged for follow-up in 24 hours for repeat CXR and evaluation after an adequate observation period.

    Tube thoracostomy Indications:
    • Air transport
    • General anesthesia
    • Hemothorax with pneumothorax
    • Patient is symptomatic
    • Patient is intubated - place a chest tube if positive pressure ventilating a traumatic pneumothorax in order to prevent a tension pneumothorax
    • Pneumothorax is >15-20% and due to trauma
    • Pneumothorax is bilateral
    • Pneumothorax is enlarging
    • Recurrent pneumothorax after a chest tube removal
    • Respiratory distress
    • Tension pneumothorax
    • Traumatic cause of pneumothorax (most)
    Percutaneous drainage of pneumothorax (simple aspiration) is successful in 65-70% of patients with moderate-sized primary spontaneous pneumothorax and in only approximately 35% of patients with secondary spontaneous pneumothorax. In a randomized study of needle aspiration versus tube thoracostomy, there was a higher immediate recurrence rate with the needle aspiration, although approximately 66% of patients experienced resolution of their pneumothorax. The recurrence rates at 3 months were similar to those for patients treated initially with tube thoracostomy

  • Bronchoscopy treatment recommendations
  • Bronchoscopy: For large air leaks, removal of foreign body or mucous plugs, and to identify trauma which may need surgical repair.

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    1. Carson-Chahhoud KV, Wakai A, van Agteren JE, et al. Simple aspiration versus intercostal tube drainage for primary spontaneous pneumothorax in adults. Cochrane Database Syst Rev. 2017;9:CD004479.
    2. Bintcliffe OJ, Hallifax RJ, Edey A, et al. Spontaneous pneumothorax: Time to rethink management? Lancet Respir Med. 2015;3(7):578-588
    3. Hedevang OW, Katballe N, Sindby JE, et al. Cannabis increased the risk of primary spontaneous pneumothorax in tobacco smokers: A case-control study. Eur J Cardiothorac Surg. 2017;52(4):679-685.
    4. Ho KK, Ong ME, Koh MS, et al. A randomized controlled trial comparing minichest tube and needle aspiration in outpatient management of primary spontaneous pneumothorax. Am J Emerg Med. 2011;29(9):1152-1157.
    5. Kelly AM, Kerr D, Clooney M. Outcomes of emergency department patients treated for primary spontaneous pneumothorax. Chest. 2008;134(5):1033-1036.
    6. Nicks B, Manthey D. Pneumothorax. In: Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 8th ed. New York, NY: McGraw-Hill Education; 2016.
    7. Parlak M, Uil SM, van den Berg JW. A prospective, randomized trial of pneumothorax therapy: Manual aspiration versus conventional chest tube drainage. Respir Med. 2012;106(11):1600-1605.
    8. Roberts DJ, Leigh-Smith S, Faris PD, et al. Clinical presentation of patients with tension pneumothorax: A systematic review. Ann Surg. 2015;261(6):1068-1078.
    9. Staub LJ, Biscaro RRM, Kaszubowski E, Maurici R. Chest ultrasonography for the emergency diagnosis of traumatic pneumothorax and haemothorax: A systematic review and meta-analysis. Injury. 2018;49(3):457-466.
    10. Thelle A, Gjerdevik M, SueChu M, et al. Randomized comparison of needle aspiration and chest tube drainage in spontaneous pneumothorax. Eur Respir J. 2017;49(4).
    11. Tschopp JM, Bintcliffe O, Astoul P, et al. ERS task force statement: Diagnosis and treatment of primary spontaneous pneumothorax. Eur Respir J. 2015;46(2):321-335.

    This is intended solely as reference material and is not a recommendation for any specific patient. The practitioner must rely upon his or her own professional judgment and medical decision-making to determine whether it is relevant in a particular case. Materials are derived from medical and nursing texts, medical literature and national guidelines and should not be considered complete or authoritative. Users must rely on specific patient presentation, experience and judgment when utilizing any of the information contained herein relative to an actual patient.

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