4.1 Trauma Assessment & Shock

Why Trauma Assessment Matters

The Trauma domain is 7-11% of the NREMT AEMT cognitive exam. Items in this domain rarely ask for a single fact in isolation. They present a scene, a mechanism of injury (MOI), a set of vital signs, and ask you to prioritize the next action. Strong performance here also feeds the Clinical Judgment domain (31-35%), because trauma scenarios are where recognizing and analyzing cues most directly changes outcomes.

The core principle: uncontrolled hemorrhage and inadequate perfusion kill trauma patients fastest. Every assessment step is built to find and treat those threats first.

Mechanism of Injury and Kinematics

Kinematics of trauma is the study of how energy transfers to the body during an injury event. You use the MOI to build an index of suspicion for injuries that may not yet be visible.

Significant MOI flags include ejection from a vehicle, death of another occupant in the same compartment, falls greater than about 20 feet (or 2-3 times the patient's height), high-speed collisions, and penetrating injury to the head, neck, or torso. A significant MOI raises the trauma-center transport priority even when the patient initially looks well.

Primary Assessment (XABCDE)

The primary assessment finds and treats immediate life threats in order. Modern trauma care moves life-threatening external hemorrhage ahead of airway:

• X — Exsanguinating hemorrhage: Stop massive external bleeding now (tourniquet or packing).
• A — Airway: Open and maintain the airway; use the modified jaw-thrust if spinal injury is suspected.
• B — Breathing: Assess rate, depth, effort, chest wall; ventilate and oxygenate inadequate breathing.
• C — Circulation: Assess pulses, skin signs, perfusion; control remaining bleeding.
• D — Disability: Rapid neuro check using AVPU (Alert, Verbal, Painful, Unresponsive) and pupils.
• E — Exposure/Environment: Expose to find hidden injuries, then prevent hypothermia.

Form a general impression within the first few seconds. A patient who is pale, diaphoretic, and altered is in shock until proven otherwise.

Secondary Assessment

After life threats are managed, perform a rapid trauma assessment (significant MOI) or a focused exam (isolated injury, no significant MOI). Use DCAP-BTLS at each body region: Deformities, Contusions, Abrasions, Punctures/penetrations, Burns, Tenderness, Lacerations, Swelling. Obtain a SAMPLE history (Signs/symptoms, Allergies, Medications, Pertinent history, Last oral intake, Events) and serial vital signs. Reassess unstable patients every 5 minutes and stable patients every 15 minutes.

External Hemorrhage Control

Control bleeding in a stepwise but rapid sequence. For an obvious life-threatening extremity bleed, move to a tourniquet without delay.

Tourniquet

Apply a commercial windlass or ratcheting tourniquet 2-3 inches proximal to the wound, never over a joint. Tighten until bright bleeding stops and the distal pulse is gone. Write the time of application on the device or the patient. Do not loosen a properly applied tourniquet in the field; periodic loosening can cause rebleeding and worsens outcomes. If one tourniquet fails to control a large limb, apply a second just proximal to the first.

Wound Packing and Pressure

For junctional or deep wounds where a tourniquet cannot be used (groin, axilla, neck), pack the wound tightly with gauze (hemostatic gauze where protocol allows) directly onto the bleeding source, then hold firm direct pressure for at least 3 minutes before applying a pressure dressing.

Shock: Recognition and Classification

Shock is inadequate tissue perfusion that fails to meet cellular oxygen demand. AEMTs must recognize shock early, before blood pressure falls.

Stages

• Compensated shock: Body maintains systolic pressure through tachycardia, vasoconstriction (pale, cool, clammy skin), and increased respiratory rate. Pulse pressure narrows. Anxiety and tachycardia are early warnings.
• Decompensated shock: Compensation fails. Hypotension, marked tachycardia, altered mentation, weak or absent peripheral pulses. This is a late, ominous sign.
• Irreversible shock: Prolonged hypoperfusion causes cell death; survival is unlikely even with aggressive care.

Types

Classic hemorrhagic shock classes: Class I (up to ~15% loss, minimal signs); Class II (~15-30%, tachycardia, narrowed pulse pressure); Class III (~30-40%, hypotension, altered mentation); Class IV (>40%, life-threatening). Estimating these classes helps anticipate deterioration even when the first set of vitals looks borderline.

AEMT IV Fluid Resuscitation

IV fluid therapy is within the AEMT scope, and the exam expects controlled, not aggressive, resuscitation for trauma.

• Establish IV access (commonly two large-bore catheters when feasible) with an isotonic crystalloid (normal saline or lactated Ringer's per local protocol).
• For hemorrhagic shock with no controlled bleeding, use permissive hypotension: titrate small fluid boluses to a palpable radial pulse and adequate mentation, not a normal blood pressure.
• Over-resuscitation raises pressure, dislodges forming clots, dilutes clotting factors, and worsens bleeding.
• Do not delay transport of a major-trauma patient to establish IV access on scene; obtain access en route.
• Definitive control of internal hemorrhage is surgical — rapid transport to a trauma center is the priority intervention, with fluids as a bridge.
• Keep the patient warm; hypothermia worsens coagulopathy (part of the lethal triad with acidosis and coagulopathy).

Transport Decisions and Field Trauma Triage

Use your system's field triage scheme (commonly based on the CDC Guideline for Field Triage) to decide destination.

• Step 1 — physiologic: Glasgow Coma Scale below 14, low systolic BP, or abnormal respiratory rate.
• Step 2 — anatomic: penetrating torso/head/neck injury, flail chest, two or more proximal long-bone fractures, pelvic instability, or paralysis.
• Step 3 — mechanism: significant MOI lowers the trauma-center threshold.
• Step 4 — special factors: age, anticoagulation, or pregnancy further lower the threshold.

Steps 1 and 2 mandate transport to the highest-level trauma center. The platinum 10 minutes / golden period concept emphasizes minimizing on-scene time for major trauma.