CTSU – Day Four: Surgical Case Studies

Case Study: Chest Trauma(Gunshot Wound)

Case 1: Chest Trauma – Gunshot Wound to the Chest

Patient: Adult male with penetrating chest trauma from a firearm.

Key History Details

• Type of firearm: High‑velocity (rifle) vs. low‑velocity (handgun).
  • High‑velocity often produces entry and exit wounds → cavitation → more tissue damage.
• Distance of shot: Approximate in meters; closer range ↑ kinetic energy transfer.
• Direction of shot: Anterior vs. posterior; determines trajectory and injured structures.
• Number of shots: Single vs. multiple entry/exit tracks.

Entry vs. Exit Wounds

Clinical tip: Always measure wound dimensions (length × width × depth) to compare entry vs. exit.

Initial Examination

1. Penetrating chest injury: Inspect for entry/exit wounds, crepitus, subcutaneous emphysema.

2. Bleeding assessment:

   • Volume estimation (qualitative):
     • Was clothing soaked? “Shirt soaked with blood?”
     • Presence of large clots? Reports of dizziness/syncope?
     • Anemic signs (tachycardia, pallor, orthostatic hypotension) suggest >20% blood loss.

3. Chest wall deformity: Flail segments, paradoxical motion.

4. Airway & breathing: Stridor, breath sounds, tracheal deviation.

5. Circulation: Pulse, blood pressure, capillary refill.

Mechanism (MIST Mnemonic)

Wounds & Tissue Injury Types

Wound: Disruption of skin and underlying tissues.

Types of Injury

Pulmonary Contusion

Definition: Bleeding into alveolar spaces without lung laceration.

Pathophysiology (Relating to GSW)

1. Shockwave from bullet → shear forces rupture alveolar capillaries.
2. Blood extravasates into interstitium and alveoli.
3. Edema & hemorrhage → ↓ lung compliance, ↓ gas exchange.
4. Inflammatory response → cytokine release, further capillary leak.
5. Ventilation–perfusion mismatch → hypoxia.

Capillary rupture -> Interstitial hemorrhage -> Alveolar flooding -> ↓ Compliance & V/Q mismatch -> Hypoxia & hemoptysis

Clinical Recognition

• Hemoptysis: Blood-streaked sputum from cough.
• Respiratory distress: Tachypnea, dyspnea, hypoxia.
• Auscultation: Crackles at injury site.
• Imaging: Patchy opacities on CXR; CT shows ground-glass attenuation.

Pulmonary Hematoma

Definition: Localized collection of blood in lung parenchyma with tissue laceration.

• Signs: Dullness on percussion, localized reduced breath sounds, consolidation on imaging.

Hissing Sound & Subcutaneous Emphysema

• Cause: Air leak from lung/pleura → tracks into subcutaneous tissue.
• Clinical hint: Feels like Rice Krispies under skin; indicates pneumothorax or bronchial injury.

Systematic Symptom Inquiry

• Head: LOC; bleeding from ears/nose; CSF otorrhea/rhinorrhea; headache; seizures.
• Neck: Pain; step-offs (cervical injury); paralysis below level of injury.
• Chest: As above.
• Abdomen:
  • Pain & distention (hemoperitoneum or ileus).
  • Splenic injury: LUQ pain radiating to left shoulder (Kehr’s sign).
  • Gallbladder injury: RUQ pain, +Murphy’s sign, radiates to right scapula.
  • Renal injury: Flank pain, gross/microscopic hematuria.
  • Bladder rupture: Lower abdominal distention; oliguria despite catheter.
  • Urethral injury: Blood at meatus; high-riding prostate.
• Limbs: Pain, swelling, deformity, neurovascular assessment.
• Back: Tenderness, step-offs; test motor & sensory in all limbs.

Grouping Injuries & Signs

• Thoracic: Entry/exit wounds, pneumothorax, hemothorax, contusion.
• Abdominal: Organ lacerations, peritonitis signs.
• Musculoskeletal: Fractures, soft tissue injuries.
• Neurological: TBI, spinal cord injury.

Treatment Overview

1. Prehospital
   • Log‑roll + spinal board (suspected spine injury).
   • Direct pressure to bleeding sites.
   • High-flow oxygen.
   • Large-bore IV access.
2. Emergency Department
   • Airway: Intubation if indicated; cricothyroidotomy for obstruction.
   • Breathing: Needle decompression → chest tube for pneumothorax/hemothorax.
   • Circulation: Fluid resuscitation; blood products; FAST ultrasound.
3. Definitive Care
   • Surgical thoracotomy or laparotomy for controlling hemorrhage and repairing organs.

Past Medical & Social History (HEADS)

H: Hypertension
E: Epilepsy
A: Asthma
D: Diabetes
S: Sickle cell disease

Example report: “No history of HTN, epilepsy, asthma, diabetes, or sickle cell disease.”

Systemic Review & Wound Documentation

• Measurement: Length × width × depth; note shape, edges, contamination.

Template Report:

Entry wound: Right anterior chest, 2.5 cm × 1.2 cm × 0.8 cm, clean inverted margins with abrasion collar.
Exit wound: Left posterior chest, 3.0 cm × 2.0 cm × 0.5 cm, everted irregular margins.

Physical Examination Reporting

General: Alert; hemodynamically stable; bilateral ankle edema (right > left).

Respiratory Examination:

Inspection: Chest symmetrical; left hemithorax expansion reduced.
Palpation: Subcutaneous emphysema over left chest.
Percussion: Hyperresonance over left upper zone.
Auscultation: Absent breath sounds left apex; crackles left base.

Abdominal Examination:

Inspection: Flat; no scars.
Auscultation: Active bowel sounds.
Percussion: Tympanic; no shifting dullness.
Palpation: Mild LUQ tenderness; no rebound or guarding.

Case 1 Assignments

1. Neck Triangles:
   • Anterior: SCM, mandible, midline. Contains carotid sheath structures & thyroid.
   • Posterior: SCM, trapezius, clavicle. Contains accessory nerve, brachial plexus roots.
2. Omohyoid Muscle: Depresses hyoid bone; landmark dividing posterior triangle into occipital/subclavian regions.
3. Cystic Hygroma: Congenital lymphatic malformation presenting as soft, cystic, transilluminant swelling in the posterior triangle; associated with Turner syndrome.

Case 2: Stab Wound with Neck Drain

Drains

Definition: Hollow tube to remove air/fluid from wound or cavity.

Characteristics: Malleable, biocompatible, non-carcinogenic, radiopaque marker.

Indications:

• Therapeutic: Evacuate hemothorax to re-expand lung.
• Diagnostic: Identify chyle leak (milky fluid) after thoracic duct injury.
• Prophylactic: Prevent seroma after mastectomy.

Removal Criteria:

• Effluent <30 mL/24 h and serous.
• Imaging confirms cavity collapse.

Drain Mechanisms:

• Gravity: Penrose draining dependent fluid.
• Suction: JP/Hemovac applying negative pressure to draw fluid.

Never close a gunshot wound primarily – risk of retained debris, infection, and tension from trapped air/blood. Case example: Mediastinal abscess developed post-primary closure, requiring re-opening and surgical drainage.

Wound Classification

• Tidy: Clean, minimal tissue loss (e.g., knife stab).
• Untidy: Ragged, contaminated (e.g., blast injury).
• Indeterminate: Unknown depth/contamination; explore and debride.

Chest Injury Classification

1. By Mechanism: Blunt vs. Penetrating.
2. By Location: Chest wall vs. Intrathoracic (heart, vessels, airways, diaphragm).
3. Deadly Dozen:
   • Lethal Six (ATOMFC): Airway obstruction; Tension pneumothorax; Open pneumothorax; Massive hemothorax; Flail chest; Cardiac tamponade.
   • Hidden Six: Pulmonary contusion; Cardiac contusion; Esophageal injury; Tracheobronchial injury; Diaphragmatic rupture; Aortic injury.

Emergency Management of Lethal Conditions

• Airway obstruction: Cricothyroidotomy/tracheostomy.
• Tension pneumothorax vs. Cardiac tamponade:
  • Tension: Hyperresonance, tracheal shift, immediate needle decompression.
  • Tamponade: Beck’s triad (hypotension, muffled heart sounds, JVD), perform pericardiocentesis.

Shock: Overview & Types

Definition: Cellular hypoxia due to inadequate perfusion.

Case 4: Infant with Hydrocephalus & VP Shunt

Indication: CSF diversion from ventricles to peritoneum/right atrium to relieve intracranial pressure.

• Alternative sites: Pleural cavity (rare), gallbladder (experimental).

End of Day Four CTSU Notes