Trauma

• Class I (<15% blood loss): normal vitals, mild anxiety — often missed
• Class II (15–30%): tachycardia, narrowing pulse pressure, anxiety, delayed capillary refill
• Class III (30–40%): tachycardia, hypotension, pale/cool/clammy skin, tachypnea, decreased urine output
• Class IV (>40%): profound hypotension, altered mental status, mottling, near arrest
• Skin: cool, pale, diaphoretic (sympathetic compensation)
• Tachycardia present even before hypotension

vs. Neurogenic shock: Hypovolemic shock has tachycardia + cool/pale/clammy skin. Neurogenic shock (spinal cord injury) produces bradycardia + warm/flushed/dry skin because sympathetic tone is lost. IV fluid is appropriate in both — but neurogenic may not respond as expected.

Narrowing pulse pressure (systolic dropping toward diastolic) is an early warning sign of compensatory vasoconstriction — it precedes hypotension. Do not wait for a low systolic BP to suspect significant hemorrhage.

• Progressive dyspnea unresponsive to oxygen or ventilatory support
• Unilateral absent or markedly decreased breath sounds
• JVD (distended neck veins from mediastinal shift)
• Tracheal deviation toward the unaffected side (late sign)
• Hypotension; tachycardia; cyanosis
• Patient deteriorating despite chest seal application or ventilation

vs. Cardiac tamponade: Both cause JVD and hypotension. Tension PTX has unilateral absent breath sounds and possible tracheal deviation. Tamponade has muffled heart sounds and equal bilateral breath sounds. Mechanism matters: tension PTX from blunt/penetrating chest; tamponade from penetrating precordial wounds.

Hemodynamic collapse in a ventilated trauma patient = tension PTX until proven otherwise. Perform needle decompression (2nd ICS MCL or 4th–5th ICS AAL) before transport. Do not wait for imaging. Reassess breath sounds after — may need bilateral decompression.

• Beck's Triad: JVD + hypotension + muffled heart sounds
• Penetrating chest trauma (particularly precordial/parasternal zone)
• Tachycardia; narrow pulse pressure; pulsus paradoxus
• Shock disproportionate to apparent blood loss
• Breath sounds equal bilaterally (distinguishes from tension PTX)
• Electrical alternans on ECG (alternating QRS complex height)

vs. Tension pneumothorax: Tamponade has EQUAL breath sounds and MUFFLED heart sounds. Tension PTX has ABSENT unilateral breath sounds and may have tracheal deviation. In the field, it can be difficult to distinguish — penetrating precordial wound with Beck's Triad favors tamponade.

In traumatic cardiac arrest with penetrating chest trauma, pericardiocentesis is a resuscitative intervention. CPR alone cannot circulate blood against a compressed heart. Consider rapid transport for thoracotomy if local protocol supports it.

• Paradoxical chest wall motion: the flail segment moves IN during inspiration (opposite to normal)
• Crepitus on palpation over multiple rib fractures
• Severe chest wall pain with breathing
• Tachypnea; progressive hypoxia
• Decreased breath sounds if hemopneumothorax co-exists
• Requires 3+ consecutive ribs fractured in 2+ places each

The flail segment itself is not the primary danger — the underlying pulmonary contusion is. SpO2 may drop progressively over hours as the contused lung fills with blood and fluid. The paradoxical motion is the visible sign; the pulmonary contusion is the real killer.

Pulmonary contusion under a flail segment can cause respiratory failure even after initial apparent stability. Monitor SpO2 closely. Consider PPV (BVM, CPAP) early in deteriorating patients — do not wait for SpO2 to crash.

• Mild (GCS 13–15): brief or no LOC, headache, amnesia, confusion — no focal deficits
• Moderate (GCS 9–12): LOC minutes to hours, focal neurological deficits, persistent confusion
• Severe (GCS <8): prolonged LOC, Cushing's Triad, decorticate/decerebrate posturing
• Fixed and dilated pupil = herniation (ipsilateral to bleed — CN III compression)
• Lucid interval: brief period of normal consciousness after head injury followed by rapid deterioration
• Vomiting, restlessness, headache worsening over time = increasing ICP

vs. Alcohol intoxication: TBI may coexist with intoxication. A fixed, dilated pupil means herniation regardless of alcohol level. Never attribute a declining GCS solely to intoxication — assume TBI and manage accordingly.

Lucid interval followed by rapid deterioration = epidural hematoma (middle meningeal artery rupture). This is a surgical emergency. Avoid hypotension — maintain SBP ≥110 mmHg (ages 15–49 and >70; ≥100 mmHg for 50–69) per current Brain Trauma Foundation guidelines — and avoid hypoxia; both worsen TBI outcome significantly.

• Loss of motor function and sensation below the level of injury
• Priapism (involuntary erection in males — sympathetic pathway disruption)
• Neurogenic shock: bradycardia + hypotension + warm/dry/flushed skin
• Loss of bowel and bladder control
• Paradoxical breathing: diaphragm moves but chest wall is still (C3–C5 injury)
• Point tenderness along the spine; midline pain

vs. Hypovolemic shock: Neurogenic shock produces bradycardia + warm/flushed skin from sympathetic disruption. Hypovolemic shock produces tachycardia + cool/pale/clammy skin. In trauma with spinal injury, both can co-exist — but treating neurogenic with aggressive fluids alone may not raise BP.

"C3, C4, C5 keeps the diaphragm alive." High cervical injuries (C3–C5) disrupt the phrenic nerve and cause apnea. Immediate BVM ventilation and airway management. Transport immediately — these patients cannot breathe independently.

• Pelvic instability on gentle compression (do not rock repeatedly)
• Perineal or scrotal ecchymosis (retroperitoneal hemorrhage tracking down)
• Lower abdominal and pelvic pain
• Leg length discrepancy; external rotation of lower extremities
• Hemodynamic instability disproportionate to visible external bleeding
• High mechanism: lateral impact MVA, fall from height, crush injury

vs. Intra-abdominal hemorrhage: Pelvic fractures bleed into the retroperitoneum — this space is NOT visualized on FAST exam. A patient in shock with a negative FAST and a high mechanism should raise suspicion for pelvic fracture. Retroperitoneal bleeds can accumulate 2–4 liters.

Unstable pelvic fracture is a potentially lethal hemorrhagic emergency. Apply a pelvic binder at the level of the greater trochanters. Do not repeatedly rock the pelvis to assess stability — each manipulation disrupts clot and increases bleeding.

• Pain out of proportion to the apparent injury
• Pain with passive stretch of the muscles in the affected compartment
• Tense, woody, "board-like" firmness of the compartment on palpation
• Paresthesia (numbness, tingling) in the distribution of nerves passing through the compartment
• Pallor of the overlying skin
• Pulselessness and paralysis are late signs — irreversible damage may already be occurring

vs. DVT: DVT causes calf pain, swelling, and tenderness but does not produce woody firmness or pain with passive stretch. Compartment syndrome is distinguished by the tenseness of the compartment and disproportionate pain that worsens with muscle use. Common contexts: long bone fracture, crush injury, or after prolonged immobilization.

Pulselessness and paralysis are late signs — by the time pulses are lost, irreversible muscle necrosis may already be occurring. Pain with passive stretch is the earliest reliable finding. Fasciotomy within 6 hours prevents permanent damage — early recognition and rapid transport are critical.