Traumatic pneumothorax

Background

• Present in 25% of patients with chest trauma

Types

1. Open
   • Communication between pleural space and atmospheric pressure (sucking chest wound)
2. Closed
3. Occult
   • Positive pressure ventilation (e.g. intubation) can convert an occult pneumothorax to a tension pneumothorax

Clinical Features

• Rib fracture and penetrating trauma most common causes
• Isolated pneumothorax does not cause severe symptoms until >40% of hemithorax is occupied

Differential Diagnosis

Pneumothorax Types

The pleural cavity is normally a potential space, in which air collects in a pneumothorax.

• Tension pneumothorax
• Spontaneous pneumothorax
  • Catamenial pneumothorax
• Traumatic pneumothorax
  • Iatrogenic pneumothorax

Thoracic Trauma

• Airway/Pulmonary
  • Bronchial injury
  • Diaphragmatic trauma
  • Hemothorax
  • Pneumomediastinum
  • Pulmonary contusion
  • Tracheal injury
  • Trachobronchial injury
  • Traumatic pneumothorax
    • Tension pneumothorax
• Cardiac/Vascular
  • Cardiac injury
    • Blunt cardiac injury
      • Cardiac contusion
      • Commotio cordis
    • Penetrating cardiac injury
    • Cardiac tamponade
  • Traumatic aortic transection
• Musculoskeletal
  • Clavicle fracture
    • Clavicle fracture (peds)
  • Rib fracture
    • Flail chest
  • Scapular fracture
  • Scapulothoracic dissociation
  • Sternoclavicular dislocation
  • Sternum fracture
  • Thoracic and lumbar fractures and dislocations
• Other
  • Esophageal injury or Perforation
  • Pneumomediastinum
  • Pneumopericardium
  • Traumatic asphyxia

Diagnosis

• Occult pneumothorax after a stab wound may be delayed for up to 6 hours
  • If patient decompensates, obtain repeat imaging

Clinically Stable

Defined as having all of the following:

• Resp rate < 24
• Heart rate 60-120 beats per minute
• Normal BP
• SaO2 >90% on room air and patient can speak in whole sentences

Workup

• CXR
  • Displaced visceral pleural line without lung markings between pleural line and chest wall
  • Upright is best
    • Expiratory films DO NOT improve accuracy
    • Lateral decubitus films with suspected side up do increase sensitivity. Good approach in pediatrics to avoid CT
  • Supine CXR = deep sulcus sign
• CT Chest
  • Very sensitive and specific

Treatment

Supplemental oxygen with non-rebreather for all

Tension pneumothorax

• Immediate needle thoracostomy followed by chest tube

Open pneumothorax

• Cover wound with three-sided dressing
  • Make sure to avoid complete occlusion (may convert injury to a tension pneumothorax)

Closed traumatic pneumothorax

• Tube thoracostomy indicated if:
  • Cannot be observed closely
  • Requires intubation
  • Will be transported by air or over a long distance
• Observation if:
  • Small AND does not require mechanical ventilation
    • Initial CXR: <1cm wide (confined to upper 1/3 of chest) OR seen only on CT
    • Unchanged on repeat CXR in hours

Adult Chest Tube Sizes

Chest Tube Size	Type of Patient	Underlying Causes
Small (8-14 Fr)	Most spontaneous pneumothorax (primary and secondary) Most iatrogenic pneumothorax	Alveolar-pleural fistulae (small air leak) Iatrogenic air
Medium (20-28 Fr)	Traumatic pneumothorax Traumatic hemothorax ("any acute hemothorax visible on chest radiograph") Pneumothorax on mechanical ventilation Non-traumatic tension pneumothorax Malignant effusion	Trauma/bleeding (hemothorax/hemopneumothorax) Bronchial-pleural fistulae (large air leak) Malignant fluid
Large (36-40 Fr)	Empyema	Thick pus

Disposition

Special Instructions

Flying

• Can consider flying 2 weeks after full resolution of traumatic pneumothroax

See Also

• Pneumothorax (main)
• Thoracic Trauma
• Hemothorax