What is the management of subcutaneous emphysema post cardiac arrest?

Management of Subcutaneous Emphysema Post Cardiac Arrest

Subcutaneous emphysema post cardiac arrest requires prompt intervention when severe, with bilateral infraclavicular incisions ("gills procedure") being the most effective emergency treatment when it interferes with effective cardiopulmonary function.

Assessment and Diagnosis

• Subcutaneous emphysema is often a symptom of a serious underlying pathologic condition but rarely requires direct treatment unless severe 1
• Evaluate for tension physiology that may impair normal cardiovascular and pulmonary function 1
• Assess for respiratory distress, airway compromise, and hemodynamic instability 1, 2
• Consider underlying causes such as pneumothorax, pneumomediastinum, tracheal injury, or esophageal perforation 3

Management Algorithm

For Severe, Life-Threatening Subcutaneous Emphysema:

1. Emergency Decompression

   • Perform bilateral infraclavicular skin incisions ("gills procedure") when subcutaneous emphysema interferes with effective CPR or causes severe respiratory compromise 1
   • This procedure allows for rapid release of trapped air and restoration of normal cardiopulmonary function 1

2. Airway Management

   • Secure the airway with endotracheal intubation if not already in place 4
   • Use waveform capnography to confirm and continuously monitor tube placement 4
   • Avoid excessive tidal volumes that may worsen air leaks 4

3. Ventilation Strategy

   • Use low tidal volume ventilation (6-8 mL/kg predicted body weight) 4, 5
   • Maintain normocapnia with PaCO2 40-45 mmHg or PETCO2 35-40 mmHg 4
   • Avoid hyperventilation which may worsen subcutaneous emphysema and cause cerebral vasoconstriction 4
   • Apply appropriate PEEP (4-8 cm H2O) to prevent atelectasis while avoiding excessive airway pressures 4, 5

For Moderate to Severe Non-Life-Threatening Subcutaneous Emphysema:

1. Subcutaneous Drain Placement

   • Insert subcutaneous drains into the affected areas (typically infraclavicular) 6, 2
   • Apply gentle suction to the drains to evacuate trapped air 6
   • This provides effective decompression of head and neck areas and reduces airway pressure 6, 2

2. Chest Tube Management (if already in place)

   • Increase suction on existing chest tubes to -20 cm H2O if a pneumothorax is present 2
   • Ensure chest tubes are patent and functioning properly 2
   • Consider additional chest tube placement if inadequate drainage 2

3. Supportive Measures

   • Position patient with head elevated to 30-45 degrees 5
   • Provide adequate sedation and analgesia to improve patient-ventilator synchrony 4
   • Consider short-term neuromuscular blockade if patient agitation is compromising ventilation 4

Monitoring and Follow-up

• Continuously monitor respiratory parameters including oxygen saturation, end-tidal CO2, and ventilatory pressures 4
• Perform serial physical examinations to assess progression or resolution of subcutaneous emphysema 2
• Obtain chest radiographs to evaluate for pneumothorax, pneumomediastinum, or other complications 5, 3
• Monitor for signs of infection, as post-cardiac arrest patients are at high risk for respiratory infections 5

Special Considerations

• Avoid excessive positive pressure ventilation that may worsen air leaks 4, 5
• Consider compressive massage of affected areas to aid in air evacuation when using subcutaneous drains 2
• For patients with persistent air leaks, surgical intervention may be necessary to identify and repair the source 2
• Be vigilant for early-onset pneumonia, which is common in post-cardiac arrest patients 5

Pitfalls and Caveats

• Subcutaneous emphysema itself is usually self-limiting and benign, requiring intervention only when severe or causing respiratory compromise 2
• Avoid excessive sedation that may mask neurological assessment in post-cardiac arrest patients 4
• Do not delay treatment of severe subcutaneous emphysema that interferes with ventilation or circulation 1
• Remember that the underlying cause (pneumothorax, tracheal injury, etc.) must be identified and treated 3
• Infraclavicular incisions, while effective, are more invasive and may leave cosmetic defects compared to drain placement 2