What is the appropriate management of surgical (subcutaneous) emphysema?

Management of Surgical (Subcutaneous) Emphysema

Most cases of subcutaneous emphysema are self-limiting and require only observation with treatment of the underlying cause, but severe cases with respiratory compromise require immediate intervention with subcutaneous drainage techniques. 1, 2

Initial Assessment and Stabilization

Immediately assess for signs of respiratory distress including stridor, accessory muscle use, tracheal tug, and sternal/subcostal/intercostal recession, as subcutaneous emphysema can signal airway compromise. 3, 1, 2

• Evaluate airway patency through clinical examination and never ignore a patient who complains of difficulty breathing, even if objective signs are absent. 3
• Provide high-flow humidified oxygen and maintain the patient in an upright position to optimize venous drainage. 3, 1
• Use waveform capnography when available to detect early airway obstruction. 3, 1, 2
• Monitor vital signs continuously including respiratory rate, heart rate, blood pressure, oxygen saturation, temperature, and level of consciousness. 3, 2
• Examine for crepitus on palpation to assess the extent and progression of subcutaneous emphysema. 1

Identify and Treat the Underlying Cause

The priority is identifying and managing the source of air leak, as subcutaneous emphysema is a symptom rather than a primary diagnosis. 1, 4, 2

Diagnostic Workup

• Obtain chest radiography immediately to detect pneumothorax, pneumomediastinum, or other thoracic injuries. 1, 2
• Consider CT scan with contrast for detailed assessment of injury extent and air collection, particularly if tracheobronchial injury is suspected. 1, 2
• Check inflammatory markers (white blood cell count, C-reactive protein) to evaluate for potential infection, especially if mediastinitis is suspected. 1, 2

Management of Pneumothorax

If pneumothorax is present, insert a small-bore chest tube (10-14F), as there is no evidence that larger tubes (20-24F) are more effective. 3, 1, 2

• Place the tube in the 5th intercostal space, mid-axillary line using proper aseptic technique to minimize infection risk (reported at 1%). 1, 2
• If a chest tube is already in place and subcutaneous emphysema develops, immediately unclamp the tube if it was clamped, check for tube patency, kinking, or displacement, and ensure proper connection to the drainage system. 1, 4

Management of Severe Subcutaneous Emphysema

For extensive subcutaneous emphysema causing significant symptoms, subcutaneous drainage provides rapid and effective decompression. 5, 6, 7, 8

Drainage Techniques (in order of invasiveness)

• Percutaneous angiocatheter decompression: Place multiple 14G angiocatheters into the subfascial space of the anterior chest wall, which provides rapid resolution within 24 hours and is superior to more invasive techniques. 7, 8
• Large-bore subcutaneous drain: Insert a 26 French intercostal catheter as a subcutaneous drain maintained under low suction (-5 cm H2O) for 24-48 hours, which provides effective decompression of head and neck areas. 5, 6
• These techniques are simple, cost-effective, minimally invasive, and avoid the need for emergency tracheostomy. 5, 6, 7, 8

Indications for Drainage

Intervene when subcutaneous emphysema is associated with:

• Palpable cutaneous tension 6
• Dysphagia or dysphonia 6
• Palpebral closure 6
• Airway compromise or respiratory failure 6, 7, 8
• Rapid progression despite treatment of underlying cause 4, 7

Warning Signs Requiring Immediate Escalation

Be vigilant for signs of mediastinitis, which can occur after airway perforation and is characterized by severe sore throat, deep cervical pain, chest pain, dysphagia, fever, and crepitus. 3, 2

• Pharyngeal and esophageal injury are difficult to diagnose, with pneumothorax, pneumomediastinum, or surgical emphysema present in only 50% of cases. 3
• Emergency intubation following Difficult Airway Society guidelines is required for severe airway compromise unresponsive to initial measures. 2
• Perform cricothyroidotomy with scalpel-bougie-tube technique if unable to intubate or oxygenate. 2

Critical Pitfalls to Avoid

Never clamp a bubbling chest tube, as this converts a simple pneumothorax into a life-threatening tension pneumothorax and worsens subcutaneous emphysema. 3, 1, 4, 2

• Do not apply fully occlusive dressings to open chest wounds without close monitoring, as this traps air and increases subcutaneous emphysema. 4
• Ensure chest tubes remain patent and properly positioned with confirmation by chest radiography. 1, 4
• Avoid attempting ventilation through a displaced tracheostomy tube or into a false passage. 1
• If suction is applied to a chest drain, the patient should be in an area with specialist nursing experience available. 3

Ongoing Management

• Most cases are cosmetically concerning but clinically benign, subsiding within days without intervention. 4
• Continue close monitoring of respiratory status and progression of subcutaneous emphysema. 1
• Maintain oxygen therapy as needed based on oxygen saturation. 1
• Keep the patient starved if airway compromise is present, as laryngeal competence may be impaired despite full consciousness. 3