Trauma Management for MCCQE1

Introduction

Trauma is a leading cause of morbidity and mortality in Canada, particularly among individuals under the age of 45. For the MCCQE1, understanding the systematic approach to the trauma patient—based on Advanced Trauma Life Support (ATLS) principles—is critical. The exam focuses heavily on prioritization, initial stabilization, and the application of specific Canadian Clinical Decision Rules.

This guide covers the essential components of trauma management, tailored to the Medical Council of Canada (MCC) objectives and the CanMEDS framework (Medical Expert, Collaborator, Health Advocate).

The Primary Survey (ABCDE)

The goal of the primary survey is to identify and treat life-threatening conditions immediately. This is a simultaneous process of assessment and resuscitation.

Adjuncts to Primary Survey

During the primary survey, the following adjuncts are standard in Canadian Emergency Departments:

• Vitals & ECG: Continuous monitoring.
• Point of Care Ultrasound (PoCUS): The eFAST (Extended Focused Assessment with Sonography for Trauma) exam to look for free fluid (pericardial, intraperitoneal) and pneumothorax.
• X-rays:
  • Chest X-ray (CXR)
  • Pelvic X-ray
  • (C-spine X-rays are largely replaced by CT in major trauma centers, but lateral C-spine may be asked in resource-limited settings).
• Catheters: Urinary catheter (contraindicated if blood at meatus) and gastric tube.

Shock Classification

Recognizing the class of hemorrhagic shock is high-yield for MCCQE1 data interpretation questions.

The Secondary Survey

Once the primary survey is complete and the patient is stable (responded to resuscitation), proceed to the secondary survey. This is a complete head-to-toe examination and detailed history.

History: AMPLE Mnemonic

• Allergies
• Medications (especially anticoagulants/beta-blockers)
• Past illnesses/Pregnancy
• Last meal
• Events/Environment related to injury

Canadian Clinical Decision Rules

For the MCCQE1, you must know when to image a patient to avoid unnecessary radiation. Canada is a world leader in developing these validated rules.

Specific Trauma Scenarios

1. Thoracic Trauma

• Tension Pneumothorax: Clinical diagnosis (distended neck veins, hypotension, tracheal deviation, absent breath sounds). Treatment: Immediate needle decompression (2nd intercostal space mid-clavicular or 5th intercostal space mid-axillary) followed by chest tube.
• Cardiac Tamponade: Beck’s Triad (Hypotension, JVD, Muffled heart sounds). Treatment: Pericardiocentesis or thoracotomy.

2. Abdominal Trauma

• Blunt Trauma: Spleen (most common), Liver.
  • Unstable: LAPAROTOMY (if positive FAST or obvious peritonitis).
  • Stable: CT Abdomen/Pelvis with contrast.
• Penetrating Trauma:
  • Gunshot Wounds: Usually require laparotomy.
  • Stab Wounds: Local wound exploration; if fascia violated, requires further workup.

3. Pelvic Fractures

• High mortality due to hemorrhage.
• Management: Pelvic binder (at level of greater trochanters) to reduce volume.
• Definitive: Angiography/Embolization for arterial bleeding; Pre-peritoneal packing.

Key Points to Remember for MCCQE1

• Primary Survey First: Never choose a CT scan as the first step for an unstable patient.
• Permissive Hypotension: In non-head trauma, target SBP 80-90 mmHg until hemorrhage is controlled to prevent “popping the clot.”
• Head Injury: If TBI is present, avoid hypotension (SBP < 90) and hypoxia (SaO2 < 90%) at all costs, as these double mortality.
• Pediatric Differences: Kids maintain BP longer but crash suddenly. Tachycardia is the earliest sign of shock in children.
• Geriatric Considerations: “Normal” BP may be hypotensive for a hypertensive senior. Beta-blockers mask tachycardia.
• Blood Types:
  • Males: O Positive uncrossmatched.
  • Females of childbearing age: O Negative uncrossmatched.

Sample Question

Clinical Scenario

A 24-year-old male is brought to the Emergency Department by EMS following a high-speed motorcycle collision. He was thrown 10 meters from the bike. On arrival, he is anxious and diaphoretic.

Vitals:

• Heart Rate: 135 bpm
• Blood Pressure: 75/50 mmHg
• Respiratory Rate: 28/min
• O2 Saturation: 88% on non-rebreather mask

Physical Exam:

• Airway: Patent.
• Neck: Trachea is deviated to the left. Distended neck veins are noted.
• Chest: Bruising over the right chest wall. Absent breath sounds on the right. Hyper-resonance to percussion on the right.
• Abdomen: Soft, non-tender.

Question

Which one of the following is the most appropriate immediate management step?

• A. Perform a portable Chest X-ray
• B. Perform endotracheal intubation
• C. Perform needle decompression of the right chest
• D. Administer 1L bolus of Ringer’s Lactate
• E. Perform an eFAST ultrasound examination

Explanation

The correct answer is:

• C. Perform needle decompression of the right chest

Detailed Explanation:

This patient presents with the classic signs of a Tension Pneumothorax:

1. Shock: Hypotension (BP 75/50) and Tachycardia (HR 135).
2. Respiratory Distress: Tachypnea and hypoxia.
3. Specific Signs: Tracheal deviation away from the injury (to the left), distended neck veins (JVD) due to obstructive shock, absent breath sounds, and hyper-resonance on the affected side (right).

Reasoning:

• C is correct: Tension pneumothorax is a clinical diagnosis. It is an immediate life threat (Breathing in ABCDE). The immediate treatment is decompression to convert the tension pneumothorax into a simple pneumothorax, restoring venous return to the heart. This is done via needle decompression (thoracostomy) or immediate finger thoracostomy, followed by a chest tube.
• A is incorrect: Delaying treatment for an X-ray in a patient with frank shock and classic signs of tension pneumothorax is dangerous and contraindicated.
• B is incorrect: While the patient is hypoxic, the primary cause is the mechanical compression of the lung and mediastinum. Positive pressure ventilation (intubation) before decompression can worsen the tension pneumothorax and lead to cardiovascular collapse.
• D is incorrect: The hypotension is caused by obstructive shock (compression of the vena cava), not primarily hypovolemia. Fluids will not fix the obstruction.
• E is incorrect: While eFAST is useful, the diagnosis is clinically apparent, and intervention should not be delayed for imaging in this unstable patient.

References

1. American College of Surgeons. (2018). ATLS: Advanced Trauma Life Support Student Course Manual (10th ed.). Chicago, IL: American College of Surgeons.
2. Stiell, I. G., et al. (2001). The Canadian CT Head Rule for patients with minor head injury. The Lancet, 357(9266), 1391-1396. Link 
3. Stiell, I. G., et al. (2001). The Canadian C-Spine Rule for radiography in alert and stable trauma patients. JAMA, 286(15), 1841-1848.
4. Medical Council of Canada. (2023). MCCQE Part I Clinical Decision-Making and Objectives.
5. CRASH-2 Trial Collaborators. (2010). Effects of tranexamic acid on death, vascular occlusive events, and blood transfusion in trauma patients with significant haemorrhage (CRASH-2): a randomised, placebo-controlled trial. The Lancet, 376(9734), 23-32.