Definition

Key History

Key Physical Exam

Risk Factors for Tension Pneumothorax

Differential Diagnosis

Diagnostic Testing

Text / literature information and recommendations include:

• None – If suspect diagnosis of tension pneumothorax, treat immediately—do not wait for chest X-ray (CXR).
• CXR:
  • Point-of-Care Ultrasonography: Increasingly used due to its high sensitivity and specificity. It is particularly useful in critically ill patients and can be performed at the bedside. Key sonographic signs include the absence of lung sliding, the presence of a lung point, and the absence of B-lines.
  • Computed Tomography: Considered the gold standard for diagnosing pneumothorax, especially in complex cases or when other imaging modalities are inconclusive.
  • 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% 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: 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.

Clinical Risk and Safety Pearls

• If tension pneumothorax is suspected, treat immediately - do not wait for CXR.
• Tube thoracostomy is a life-saving intervention delayed while waiting for X-ray results.

Treatment

• 100% oxygen
• Immediate needle decompression - do not wait for CXR
  • Insert a large bore IV catheter (14-16 gauge best, 18 gauge okay) into 2nd intercostal space, midclavicular line (1-2 cm from sternal edge), just superior to the third rib. Leave plastic sheath on needle; more than one needle may need to be placed. If tension pneumo is present, a rush of air will likely be heard through the needle—this is diagnostic as well as therapeutic. Must have chest tube placement after this procedure regardless of whether rush of air is present or not.
• After immediate needle decompression, place chest tube
• CXR
• Acute surgery consult
• Monitor vital signs
• Admit all patients

Complications

• Hemothorax after needle decompression
• Intercostal neurovascular bundle injury from thoracostomy tube placement
• Misdiagnosis of a pneumothorax as a tension pneumothorax, thereby converting a pneumothorax into an open pneumothorax