Understanding Pneumothorax: Risk Factors and Differential Diagnosis

Risk Factors for Pneumothorax

• Secondary pneumothorax
  • Trauma: rib fractures, blunt chest trauma (as in the case).
  • Iatrogenic: central line placement, thoracentesis, pleural procedures.
• Primary spontaneous pneumothorax
  • Young, tall, thin males (10–30 years).
  • Connective tissue disorders: Marfan, Ehlers-Danlos.
  • Underlying lung disease: COPD with bullae, interstitial lung disease, CF, TB, malignancy.
• Technically, anyone is at risk.

Symptoms & Differential Diagnosis

• Typical PTX presentation: Dyspnea, chest pain, pleuritic discomfort.
• Exam clues: unilateral decreased breath sounds, focal tenderness/crepitus.
• Red flags (suggest tension PTX):
  • JVD
  • Tracheal deviation
  • Hypotension, shock physiology
  • Severe tachycardia, hypoxia
• Differential diagnoses:
  • Pulmonary: asthma, COPD, pneumonia, pulmonary edema (SCAPE), ILD, infections.
  • Cardiac: ACS, CHF, pericarditis.
  • PE and other acute causes of dyspnea.

Diagnostics

• Bloodwork: limited role, except type & screen if intervention likely.
• EKG: reasonable given chest pain/shortness of breath.
• Imaging:
  • POCUS (bedside ultrasound)
    • High sensitivity (86–96%) & specificity (97–100%).
    • Signs:
      • Seashore sign: normal lung sliding.
      • Barcode sign: absent lung sliding.
      • Lung point: most specific for PTX.
  • CXR
    • Sensitivity ~70–90% for small PTX.
    • May show pleural line, hyperlucency.
  • CT chest (gold standard)
    • Defines size/severity.
    • Rules out mimics (bullae, pleural effusion, hemothorax).
    • Guides intervention choice.

Management

• First step for all: Oxygen supplementation (non-rebreather if possible).
  • Accelerates resorption of pleural air.
• Stable vs. unstable decision point:
  • Unstable/tension PTX
    • Immediate needle thoracostomy (14-g angiocath, 2nd ICS midclavicular).
    • Temporizing until chest tube/pigtail placed.
  • Stable, small PTX (<2 cm on O₂)
    • Observation, supplemental O₂, conservative management.
  • Stable, larger PTX or symptomatic
    • Chest tube or pigtail catheter insertion.
    • Pigtail catheters: less invasive, more comfortable, similar efficacy for simple PTX.
    • Large bore tubes: indicated if associated with blood, pus, large collections.

Disposition

• Admit all patients with chest tubes; cannot be discharged with tube in place.
• Service responsible varies by hospital: trauma, CT surgery, MICU, etc.
• Level of care (ICU vs. floor) depends on stability:
  • ICU if unstable course, intubated, shock physiology.
  • Stepdown/floor if stable and straightforward.

Take Home Points

• Always broaden differential in dyspnea/chest pain → don’t anchor on asthma/COPD.
• Exam findings + history (trauma, risk factors) crucial to raising suspicion.
• Ultrasound is more sensitive than CXR and highly specific when lung point found.
• Oxygen is first-line; intervention determined by size + stability.
• Pigtail catheters increasingly favored for simple, stable PTX.
• All patients with intervention require admission; service varies by institution.