Trauma Management: Myocardial Contusion and Penetrating Cardiac Injury

Tracheobronchial Tree Injuries

• Can be managed conservatively or surgically depending on the location and extent of the injury
• Surgical approach depends on the location of the injury:
  • Cervical collar incision: proximal trachea
  • Right postero-lateral thoracotomy: lower trachea, carina, right main bronchus (RMB), and proximal left main bronchus (LMB)
  • Left postero-lateral thoracotomy: distal LMB
• Options for management: primary repair, sleeve resection, and lung resection

Foreign Body in the Airway

• Management: acute cases require urgent bronchoscopy with or without bronchotomy, while chronic cases require bronchoscopy with precaution and possible lung resection

Esophageal Injuries

• Rare in blunt trauma, more common in penetrating trauma (stab or trans-mediastinal gunshot injury)
• Cervical esophageal injuries are most common
• Clinical features:
  • Pneumothorax (left)
  • Haemothorax without rib fractures
  • Lower sternum or epigastric pain (severe blunt trauma)
  • Particulate matter in the ICD
  • Penetrating injury that has crossed the mediastinum
  • Odynophagia
  • Dysphagia
  • Surgical emphysema
  • Mediastinitis
• Investigations:
  • Combination of clinical suspicion, CXR, water-soluble contrast swallow, and oesophagoscopy
• Management:
  • Timing: debride and drain within 24 hours
  • Surgical repair or resection with delayed reconstruction
  • Via:
    • RPLT 4th ICS for upper esophagus
    • LPLT 6th ICS for lower esophagus
• Complications:
  • Mediastinal contamination
  • Abscess formation
  • Empyema thoracis

Foreign Body in the Esophagus

• Types: bone, meat, battery, coin
• Clinical presentation:
  • Acute: dysphagia, choking, hematemesis
  • Chronic: hemoptysis, coughing when feeding
• Management: oesophagoscopy with or without mediastinal drainage and repair

Diaphragmatic Injuries

• Often occult, easily missed; left diaphragm most commonly detected
• Marker of severe thoracoabdominal trauma
• Types: blunt vs penetrating (stab/iatrogenic-ICD)
• Clinical features:
  • With or without signs of bowel obstruction
  • Drainage of peritoneal content via chest drain
  • NGT in the chest (CXR)
  • Herniation of GIT
  • Acute, delayed, common left
• Investigations:
  • CXR: elevated hemidiaphragm, haemo-pneumo
  • Swallow and follow through
  • Contrast-enhanced CT scan
• Management: surgical repair via thoracotomy vs thoraco-abdominal incision vs laparotomy, or laparoscopy

Cardiac Injuries

• Penetrating: myocardial contusion, valve injuries, IVS rupture
• Blunt: myocardial contusion, valve injuries, IVS rupture
• Frequency of injury: 20-25% of thoracic deaths worldwide
• Male vs female: male dominance
• Age: bimodal distribution
• Mechanism of injury:
  • Penetrating: high-velocity (gunshots) or low-velocity (stab wounds)
  • Blunt: direct (assault and blast) or indirect (falls, MVA)
  • Transfixing

Syllabus

• Chest wall (muscle and bone)
• Pleura
• Lung parenchyma
• Tracheobronchial tree (and foreign body)
• Esophagus (and foreign body)
• Diaphragm
• Cardiovascular

Thoracic Trauma

• Thoracic injury accounts for 20-25% of thoracic deaths worldwide
• Male vs female: male dominance
• Age: bimodal distribution
• Mechanism of injury:
  • Penetrating: high-velocity (gunshots) or low-velocity (stab wounds)
  • Blunt: direct (assault and blast) or indirect (falls, MVA)
  • Transfixing

Initial Evaluation

• Goal: prompt identification of life-threatening injuries
• Pathology:
  • Airway obstruction
  • Loss of oxygenation or ventilation
  • Hypovolemia
  • Obstructive shock
  • Ventilation-perfusion mismatch
• Physiological causes of death:
  • Tissue hypoxia
  • Hypercarbia
  • Metabolic acidosis

Acceleration-Deceleration

• Shearing, tearing, and traction forces in relation to structures being more fixed than others
• Aorta, heart, and esophagus are more susceptible to injury

Initial Evaluation

• Primary survey (Airway-Breathing-Circulation):
  • Airway obstruction
  • Tension pneumothorax
  • Open pneumothorax/sucking chest wound
  • Flail chest
  • Massive haemothorax
  • Cardiac tamponade
• Secondary survey (with the aid of imaging, record every injury from head to toe, systemically)

Traumatic Rib Fractures

• Other bony fractures of the chest wall
• Sternal fractures:
  • Up to 4%
  • Transverse, in the upper or midportions
  • Associated injuries: myocardium
  • Clinical features: point of tenderness, swelling, and deformity
  • Investigations: ECG, cardiac enzymes, formal ECHO/TEE
  • Management: supportive, surgical (help wean off MV)