What is the procedure for performing an emergency thoracotomy in an unresponsive adult patient with a penetrating chest injury, cardiac arrest, and signs of cardiac tamponade or massive hemothorax?

Emergency Thoracotomy Procedure

For an unresponsive adult with penetrating chest trauma, cardiac arrest, and suspected cardiac tamponade or massive hemothorax, perform an immediate left anterolateral thoracotomy in the 4th or 5th intercostal space, open the pericardium, evacuate blood/clot, perform direct cardiac compression, control hemorrhage, and cross-clamp the descending aorta if needed. 1

Indications for Emergency Thoracotomy

Proceed immediately if:

• Penetrating chest trauma with cardiac arrest occurring <15 minutes before arrival, especially with witnessed loss of vital signs 1
• Signs of life present in the field (any cardiac electrical activity, pupillary response, respiratory effort, or extremity movement) 2
• Stab wounds have significantly better outcomes (34% survival) than gunshot wounds (8% survival) 2, 3
• Clinical evidence of cardiac tamponade (Beck's triad, muffled heart sounds, distended neck veins) 1, 4

Do NOT perform if:

• No signs of life on initial prehospital assessment (absent pulse, respirations, pupillary reflexes, and cardiac electrical activity) - 0% survival 2
• Blunt trauma with cardiac arrest - relative contraindication with only 2% survival 2
• Cardiac arrest >15 minutes duration from penetrating trauma 1

Surgical Technique: Step-by-Step

1. Incision and Chest Entry

• Position patient supine with left arm abducted 1
• Make a left anterolateral thoracotomy incision in the 4th or 5th intercostal space from sternum to posterior axillary line 1
• If bilateral access needed, extend across sternum (clamshell incision) to improve exposure of heart, great vessels, and right hemithorax 1
• Use heavy scissors or rib spreaders to enter pleural space 1

2. Pericardial Management

• Open the pericardium anterior to the phrenic nerve with a longitudinal incision to avoid nerve injury 1, 4
• Evacuate blood and clot from pericardial sac - this alone may restore cardiac output if tamponade present 4, 3
• Extend pericardiotomy superiorly and inferiorly for full cardiac exposure 1

3. Direct Cardiac Compression

• Use two-handed technique: place one hand behind heart, compress against other hand on anterior surface 5
• Alternative: thumb-and-fingers technique or palm against sternum with extended fingers 5
• Compress at 100-120/minute, allowing complete cardiac relaxation between compressions 5
• Direct cardiac compression generates double the cardiac index (1.3 vs 0.6 L/min/m²) compared to external compressions 5

4. Control Hemorrhage

• For cardiac wounds: Apply direct digital pressure initially, then place horizontal mattress sutures with pledgets or running 3-0/4-0 polypropylene 3
• Avoid coronary arteries when suturing - place sutures beneath visible coronary vessels 3
• For lung lacerations: Apply direct pressure, use lung stapler for tractotomy, or perform emergency pneumonectomy if exsanguinating 1
• For great vessel injuries: Apply vascular clamps proximally and distally, repair primarily or with patch 1

5. Aortic Cross-Clamping

• Cross-clamp the descending thoracic aorta just above the diaphragm to redirect blood flow to heart and brain 1
• This is critical for patients with massive subdiaphragmatic hemorrhage 1
• Use aortic cross-clamp or DeBakey clamp 1

6. Defibrillation

• Perform internal defibrillation if ventricular fibrillation present using 10-20 joules initially 1
• Place paddles directly on ventricular myocardium 1
• Ensure no personnel contact with patient or fluids during shock 1

Critical Adjuncts During Procedure

• Ensure massive transfusion protocol activated - resuscitative thoracotomy must occur with simultaneous aggressive blood product resuscitation 1
• Ventilate with lower tidal volumes (6-8 mL/kg) and lower respiratory rates to minimize auto-PEEP and barotrauma 1, 5
• Target oxygen saturation ≥94% but avoid hyperoxia 5
• Maintain limited fluid resuscitation until hemorrhage controlled to avoid dilutional coagulopathy 1

Outcomes and Prognostic Factors

Best survival rates occur with: 2, 3, 6

• Stab wounds (34-57% survival) vs gunshot wounds (8% survival)
• Cardiac tamponade as primary pathology (54-64% survival)
• Blood pressure 60-90 mmHg with subsequent arrest (56% survival)
• Profound shock (BP <60 mmHg) at presentation (64% survival)
• Loss of pulse in presence of experienced physician (10% prehospital survival)

Overall survival: 7.8-13% for all emergency thoracotomies, but 22% for penetrating trauma specifically 2, 7

Common Pitfalls to Avoid

• Delaying thoracotomy for transport - if arrest >10 minutes from emergency department, consider prehospital thoracotomy by trained physician 6
• Performing on patients with no signs of life in field - this is futile with 0% survival 2
• Injuring phrenic nerve - always open pericardium anterior to nerve 1, 4
• Excessive ventilation - causes auto-PEEP, decreased venous return, and cardiovascular collapse 1, 5
• Attempting in blunt trauma cardiac arrest - only 2% survival, generally contraindicated 2
• Inadequate blood product resuscitation - thoracotomy without transfusion is futile 1

Post-Resuscitation Management

• Transfer immediately to operating room for definitive repair if return of spontaneous circulation achieved 1, 3
• Consider mechanical circulatory support (ECMO) if refractory to standard measures and potentially reversible cause 1, 5
• Send pericardial fluid for analysis (chemistry, microbiology, cytology) 4
• Monitor for complications: infection (18% superficial wound infections reported), neurological injury, graft damage if post-cardiac surgery 1, 3