What is the appropriate evaluation and management for a patient presenting with subclavicular subcutaneous emphysema?

Evaluation and Management of Subclavicular Subcutaneous Emphysema

Immediate Assessment

Rapidly assess for airway compromise by checking for stridor, accessory muscle use, tracheal tug, and chest wall recession, as subcutaneous emphysema in this location may herald impending respiratory failure. 1

• Examine for signs of respiratory distress including dyspnea, tachypnea, and use of accessory muscles, even if objective findings initially appear minimal 1
• Palpate for crepitus extending into the neck and face, which indicates air tracking along tissue planes and potential airway threat 2
• Check vital signs continuously including respiratory rate, heart rate, oxygen saturation, and blood pressure to detect rapid deterioration 1
• Administer high-flow humidified oxygen immediately and position the patient upright to promote venous drainage of subcutaneous air 1
• Utilize waveform capnography when available to detect early airway obstruction 1

Identify the Underlying Cause

Obtain immediate chest radiography to identify pneumothorax, pneumomediastinum, or thoracic injuries that are the source of subcutaneous air. 1

• Look for pneumothorax on chest X-ray, as this is the most common cause requiring intervention 3, 1
• Evaluate for signs of esophageal or tracheal injury if there is history of trauma, foreign body ingestion, or recent procedures 3, 4
• In trauma patients with subclavicular emphysema, obtain CT angiography of the head and neck as first-line imaging (sensitivity 90-100%) to simultaneously identify vascular injury, aerodigestive tract violation, and the trajectory of air entry 4
• Consider CT scan with contrast for detailed assessment if chest radiography is inconclusive or if mediastinal injury is suspected 1

Critical Clinical Pitfalls

Always evaluate for "hard signs" requiring immediate surgical exploration: active hemorrhage, expanding hematoma, airway compromise, hemodynamic instability, or air bubbling from wounds. 4

• Assess for aerodigestive tract injury by asking about dysphagia, dysphonia, hemoptysis, or hematemesis 4
• Be alert for mediastinitis after airway perforation, manifested by severe sore throat, deep cervical pain, chest pain, dysphagia, fever, and crepitus—these are red-flag symptoms requiring urgent intervention 1
• Recognize that pharyngeal or esophageal injuries may be present even when pneumothorax or pneumomediastinum are absent in up to 50% of cases 1
• Keep the patient nil per os (fasted) when airway compromise is present, as laryngeal competence may be impaired 1

Management of Associated Pneumothorax

If pneumothorax is identified, insert a small-bore chest tube (10-14 French) as there is no evidence that larger tubes (20-24 French) are more effective. 1

• Place the tube in the 5th intercostal space, mid-axillary line using proper aseptic technique 1
• Never clamp a bubbling chest tube, as this can convert a simple pneumothorax into life-threatening tension pneumothorax and worsen subcutaneous emphysema. 1
• Delay applying suction until lung re-expansion is confirmed to avoid re-expansion pulmonary edema 1
• Ensure chest tube care occurs in a setting with specialist nursing expertise when suction is applied 1

Management of Severe Subcutaneous Emphysema

For most cases, subcutaneous emphysema is self-limited and requires only observation with treatment of the underlying cause 5, 6, 7

However, if subcutaneous emphysema is rapidly progressive, causing respiratory distress or patient discomfort, place multiple percutaneous 14-gauge angiocatheters into the subfascial space of the anterior chest wall for decompression. 5, 8

• This technique provides rapid symptom relief within 24 hours and is superior to large open "blow hole" incisions 5
• The angiocatheter approach is well-tolerated, readily accessible, low-cost, and simple to perform 5, 8
• Continue supportive care with high-flow oxygen and upright positioning 1

Escalation Criteria

Obtain thoracic surgical consultation after 3-5 days if persistent air leak or failure of lung re-expansion occurs; consult earlier (within 2-4 days) if the patient has underlying lung disease or large-volume air leaks. 1

• Open thoracotomy with pleurectomy has the lowest recurrence rate for refractory air-leak cases 1
• Prepare for rapid-sequence induction and intubation if airway obstruction develops, as delayed presentations can deteriorate rapidly 2

Ongoing Monitoring

• Monitor for progression of subcutaneous emphysema by serial physical examinations 1, 6
• Continue oxygen therapy based on saturation levels 1
• Average resolution time varies but most cases resolve with treatment of the underlying cause 6
• Patients who are not systemically ill with minimal pain, no significant inflammatory changes, and stable hemodynamics can be managed conservatively with close observation, but maintain high suspicion for necrotizing fasciitis if clinical deterioration occurs 7