21.1 Major Trauma Resuscitation & Initial Assessment

Advanced Trauma Life Support (ATLS 10th Edition) Principles

Trauma remains the leading cause of mortality in individuals under 45 years of age and the fourth leading cause of death overall in North America. The management of major trauma is grounded in the trimodal distribution of trauma mortality, which dictates clinical priorities and resuscitation timing:

1. First Peak (Immediate Deaths; Seconds to Minutes): Caused by catastrophic neurological or vascular destruction (brainstem laceration, high cervical cord transection, thoracic aortic dissection/rupture, cardiac rupture). These injuries are rarely salvageable in the hospital setting and are addressed primarily through public health prevention and vehicle safety design.
2. Second Peak (Early Deaths; Minutes to Several Hours): The traditional "Golden Hour" of trauma medicine. Fatalities during this window are caused by life-threatening thoracic and abdominal crises (tension pneumothorax, massive hemothorax, cardiac tamponade, subdural or epidural hematomas, ruptured spleen or liver, unstable open-book pelvic ring fractures) and severe exsanguinating hemorrhagic shock. This stage represents the primary target of the ATLS Primary Survey and damage control resuscitation.
3. Third Peak (Late Deaths; Days to Weeks Post-Injury): Resulting from severe systemic sepsis, multi-organ dysfunction syndrome (MODS), acute respiratory distress syndrome (ARDS), and refractory intracranial hypertension. The incidence and severity of third-peak mortality are directly linked to the quality and timeliness of resuscitation delivered during the second peak.

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The Primary Survey: The ABCDE Hierarchy

The Primary Survey is executed in a strict, unwavering hierarchical sequence (A-B-C-D-E) designed to detect and treat the most immediately lethal physiological derangements first. Resuscitation occurs simultaneously with diagnosis: clinicians must never progress to the next letter in the sequence until the preceding life-threatening condition has been identified and addressed.

                             THE ATLS PRIMARY SURVEY HIERARCHY

  ┌────────────────────────────────────────────────────────────────────────────────────────┐
  │ A: AIRWAY WITH CERVICAL SPINE PROTECTION                                              │
  │ • Manual in-line stabilization or rigid collar • Clear oral cavity • RSI if GCS ≤8     │
  └───────────────────────────────────────────┬────────────────────────────────────────────┘
                                              │ Patency secured
                                              ▼
  ┌────────────────────────────────────────────────────────────────────────────────────────┐
  │ B: BREATHING & VENTILATION (ELIMINATE THORACIC LIFE THREATS)                           │
  │ • Tension Pneumothorax (Decompress) • Massive Hemothorax (Chest tube 28-32 Fr)         │
  │ • Open Pneumothorax (3-sided dressing) • Flail Chest (Analgesia, toilet, PPV)          │
  └───────────────────────────────────────────┬────────────────────────────────────────────┘
                                              │ Thoracic life threats eliminated
                                              ▼
  ┌────────────────────────────────────────────────────────────────────────────────────────┐
  │ C: CIRCULATION & HEMORRHAGE CONTROL                                                    │
  │ • Direct pressure & tourniquets • Pelvic binder over greater trochanters               │
  │ • Two large-bore 16G IVs or IO • Permissive hypotension (SBP 80-90)                    │
  │ • 1:1:1 Balanced MTP (PRBC:FFP:Plt) • TXA 1g bolus within 3 hours of injury            │
  └───────────────────────────────────────────┬────────────────────────────────────────────┘
                                              │ Hemorrhage managed & access established
                                              ▼
  ┌────────────────────────────────────────────────────────────────────────────────────────┐
  │ D: DISABILITY (RAPID NEUROLOGICAL ASSESSMENT)                                          │
  │ • Glasgow Coma Scale (GCS 3-15) • Pupillary symmetry & reactivity • Lateralizing signs  │
  └───────────────────────────────────────────┬────────────────────────────────────────────┘
                                              │ Baseline neurology recorded
                                              ▼
  ┌────────────────────────────────────────────────────────────────────────────────────────┐
  │ E: EXPOSURE & ENVIRONMENTAL CONTROL                                                    │
  │ • Undress completely • Full skin inspection & log roll • Prevent Lethal Triad (Warming)│
  └────────────────────────────────────────────────────────────────────────────────────────┘

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A — Airway with Cervical Spine Protection

Airway compromise kills faster than breathing failure, which kills faster than circulatory exsanguination. Airway assessment begins by asking the patient a simple question (e.g., "What is your name?"). A clear, coherent verbal response confirms airway patency, intact cerebral perfusion, and reasonable ventilatory mechanics. Stridor, gargling, dysphonia, or tachypneic grunting signals impending loss of patency.

Cervical Spine Immobilization

• In any blunt trauma mechanism (motor vehicle collision, fall, bicycle crash, direct head impact), the cervical spine must be assumed unstable until cleared clinically or radiographically.
• Maintain continuous manual in-line stabilization (MILS) during all airway maneuvers. When using an active rigid cervical collar, the anterior collar piece is detached while an assistant holds the patient's head, mastoid processes, and occiput rigidly neutral without axial traction.

Indications for Definitive Airway (Endotracheal Intubation)

• Severe Neurologic Depression: Glasgow Coma Scale (GCS) score $\le 8$ ("GCS of eight, intubate").
• Mechanical Airway Obstruction: Expanding neck hematoma, massive maxillofacial smash injuries, retropharyngeal edema, or foreign body aspiration.
• Impending Airway Compromise: Inhalation injury with facial burns, singed nasal vibrissae, or laryngeal stridor.
• Ventilatory Failure: Severe refractory hypoxemia ($PaO_2 < 60\text{ mmHg}$ despite high-flow oxygen), hypercapnic exhaustion, or severe chest wall disruption.
• Controlled Resuscitation: Combative, severely agitated trauma patients requiring emergency CT scanning or urgent operative damage control.

Rapid Sequence Intubation (RSI) in Trauma

• Pre-oxygenation: Deliver $100%\text{ }O_2$ via non-rebreather mask or bag-valve-mask (avoiding vigorous positive-pressure bagging to prevent gastric insufflation and passive regurgitation).
• Induction Agent: Etomidate ($0.3\text{ mg/kg}$ IV) is the standard induction agent due to its hemodynamically neutral profile (minimal myocardial depression, no peripheral vasodilation). Ketamine ($1.5\text{ to }2.0\text{ mg/kg}$ IV) is an excellent alternative in profound hemorrhagic shock, as it preserves sympathetic vascular tone and provides intrinsic bronchodilation.
• Neuromuscular Blocker: Succinylcholine ($1.5\text{ mg/kg}$ IV) delivers rapid paralysis within 45 to 60 seconds with short duration (6–10 min). Caution: Contraindicated in denervating neurological injuries $>48\text{ hours}$ old, major crush injury $>48\text{ hours}$ old, preexisting severe hyperkalemia, or personal/family history of malignant hyperthermia. In these settings, use Rocuronium ($1.2\text{ mg/kg}$ IV).
• Definitive Surgical Airway (Cricothyroidotomy): When orotracheal intubation fails in a "cannot intubate, cannot oxygenate" (CICO) scenario, emergency surgical cricothyroidotomy via the scalpel-bougie-tube technique is mandatory through the cricothyroid membrane. Pediatric Rule: In children younger than 8 to 12 years, the cricoid cartilage is the narrowest, most fragile part of the airway; surgical cricothyroidotomy risks permanent subglottic stenosis. Perform needle cricothyroidotomy with trans-tracheal jet insufflation (12- to 14-gauge catheter) as a temporary bridge.

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B — Breathing and Ventilation: Immediate Thoracic Life Threats

Once an airway is secured, the clinician exposes the chest, inspects respiratory excursion, palpates for flail segments or subcutaneous crepitus, auscultates breath sounds bilaterally, and percusses the hemithoraces. Four thoracic life threats must be identified and decompressed immediately:

1. Tension Pneumothorax

• Pathophysiology: A one-way "ball-valve" laceration in the visceral or parietal pleura permits air entry into the pleural space during inspiration but prevents exit during expiration. Intrapleural pressure escalates above atmospheric and central venous pressures, causing complete collapse of the ipsilateral lung, shifting the mediastinum and trachea away from the affected side, and angulating/compressing the superior and inferior vena cava. Venous return (preload) to the right atrium drops precipitously, producing severe obstructive shock and rapid progression to pulseless electrical activity (PEA) arrest.
• Cardinal Signs: Severe dyspnea, tachypnea, extreme cyanosis, profound hypotension, tachycardia, unilaterally absent or diminished breath sounds, hyperresonance to percussion, ipsilateral flattened chest excursion, distended jugular veins (JVD), and contralateral tracheal deviation (a late, pre-terminal sign).
• Mandatory Procedural Action:
  • Tension pneumothorax is a PURELY CLINICAL DIAGNOSIS. Clinicians must NEVER order or await a chest radiograph in an unstable patient with clinical signs of tension pneumothorax.
  • Immediate Needle Thoracostomy (Needle Decompression): Insert a large-bore (14- or 16-gauge) angiocatheter with a length of at least 3.25 inches (8 cm). (Standard 1.75-inch catheters fail to penetrate the thoracic pleural space in $>50%$ of adults due to chest wall and pectoralis thickness).
  • Anatomical Sites (ATLS 10th Edition):
    • Primary Preferred Site: 5th intercostal space at or just anterior to the anterior axillary line (the safe triangle). This site features thinner chest musculature and a higher procedural success rate than traditional anterior approaches.
    • Alternative Site: 2nd intercostal space in the midclavicular line, inserting the needle just superior to the 3rd rib to avoid the neurovascular bundle (intercostal vein, artery, and nerve) traveling along the inferior rib border.
  • Finger Thoracostomy (Mini-Thoracostomy): In mechanically ventilated or morbidly obese patients, emergency finger thoracostomy at the 5th intercostal space anterior axillary line reliably decompresses tension physiology.
  • Immediate Follow-Up: Needle or finger decompression must be immediately followed by formal tube thoracostomy (28 to 32 French chest tube) connected to underwater seal suction ($-20\text{ cm }H_2O$).

2. Massive Hemothorax

• Pathophysiology: Accumulation of $>1,500\text{ mL}$ of blood (or $>200\text{ mL/hour}$ over 2 to 4 hours) in the pleural space, most commonly from laceration of systemic thoracic arteries (internal mammary or intercostal arteries) or major hilar vessels.
• Clinical Presentation: Profound hemorrhagic shock, unilateral absent breath sounds, dullness to percussion on the affected hemithorax, and collapsed/flat neck veins (hypovolemia).
• Emergency Management:
  • Rapid placement of a large-bore chest tube (28 to 32 French) placed at the 5th intercostal space anterior axillary line directed posteriorly and superiorly.
  • Immediate initiation of balanced component blood resuscitation via Massive Transfusion Protocol (MTP), utilizing an autotransfusion system to re-infuse evacuated shed pleural blood.
  • Indications for Emergent Operative Thoracotomy:
    1. Immediate initial chest tube drainage of $\ge 1,500\text{ mL}$ of blood upon placement;
    2. Ongoing, active chest tube output of $\ge 200\text{ mL/hour}$ for 2 to 4 consecutive hours;
    3. Persistent, refractory hemodynamic instability despite aggressive balanced blood resuscitation.

3. Open Pneumothorax ("Sucking Chest Wound")

• Pathophysiology: A full-thickness traumatic chest wall defect whose diameter exceeds two-thirds the diameter of the trachea. Air preferentially enters the pleural space through the thoracic wall defect (path of least resistance) rather than through the trachea, causing immediate lung collapse and profound ventilatory insufficiency.
• Immediate Procedural Action: Apply a sterile occlusive dressing (petrolatum gauze) taped securely on THREE SIDES. This creates a temporary flutter-valve mechanism: during expiration, intrapleural pressure rises and drives air out through the untaped fourth side; during inspiration, negative intrathoracic pressure sucks the dressing flat against the skin, preventing atmospheric air ingress. Never tape all four sides without a chest tube in place, as this converts an open pneumothorax into a fatal tension pneumothorax. Place a formal tube thoracostomy through a separate, remote incision.

4. Flail Chest & Severe Pulmonary Contusion

• Pathophysiology: Occurs when $\ge 2$ contiguous ribs are fractured in $\ge 2$ separate locations, creating a free-floating chest wall segment that uncouples from the thoracic cage and displays paradoxical motion (sucked inward during inspiration; pushed outward during expiration). However, the primary cause of life-threatening hypoxemia is not the paradoxical motion itself, but the underlying severe pulmonary contusion (alveolar hemorrhage, microvascular disruption, surfactant loss, and non-cardiogenic consolidation).
• Management: Aggressive multimodal analgesia (thoracic epidural analgesia, paravertebral nerve block, patient-controlled IV opioids) to prevent splinting and hypoventilation, dedicated pulmonary toilet, and humidified supplemental oxygen. Judicious fluid administration prevents worsening interstitial contusion edema. Endotracheal intubation with positive-pressure mechanical ventilation is reserved for severe hypoxemia refractory to oxygenation, progressive hypercapnic fatigue, or severe shock.

Diagnostic Differentiation of Thoracic Life Threats

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C — Circulation with Hemorrhage Control

Hemorrhage is the leading cause of preventable death in major trauma. Resuscitation focuses on rapid external hemostasis, pelvic stabilization, vascular access, and modern damage control resuscitation.

External Hemorrhage Control & Pelvic Ring Stabilization

• Direct External Hemorrhage: Apply firm, continuous manual pressure directly over bleeding lacerations. For catastrophic extremity hemorrhage unresponsive to pressure, apply a commercial extremity tourniquet (Combat Application Tourniquet [CAT]) 2 to 3 inches proximal to the injury site (or "high and tight" on the limb). Tighten the windlass until active arterial bleeding and distal pulses cease. Document the exact application time; tourniquets can remain safely in place for up to 2 hours without irreversible ischemic nerve or muscle damage.
• Suspected Pelvic Ring Disruption ("Open-Book" Fracture): Anteroposterior compression injuries disrupt the pubic symphysis (diastasis $>2.5\text{ cm}$) and tear the posterior sacroiliac venous plexus and internal iliac arterial branches, creating an expandable retroperitoneal space capable of harboring 3 to 4 liters of blood. Clinicians must apply a commercial pelvic binder or tightly folded bedsheet wrapped circumferentially and centered strictly over the GREATER TROCHANTERS of the femurs (NOT over the iliac crests). Clinical Red Flag: Do NOT perform repeated manual "pelvic rocking" or compressive testing of an unstable pelvis, as this shears fragile retroperitoneal venous clots and triggers fatal re-bleeding.

               PELVIC BINDER PLACEMENT: CRITICAL ANATOMICAL LANDMARK

     Incorrect (Iliac Crests):               CORRECT (Greater Trochanters):
     ┌────────────────────────┐              ┌────────────────────────┐
     │  [ Iliac Crests ]   X  │ ◄─ WRONG     │  [ Iliac Crests ]      │
     │           │            │  (Fails to   │           │            │
     │   [ Pelvic Cavity ]    │   reduce     │   [ Pelvic Cavity ]    │
     │           │            │   volume)    │           │            │
     │ [ Greater Trochanters] │              │ [Greater Trochanters]◄─┼── ACCURATE (Closes the
     └────────────────────────┘              └────────────────────────┘   pelvic volume & tamponades
                                                                          retroperitoneal venous plexus)

Vascular Access

• Rapidly place two large-bore peripheral IV catheters (16- or 14-gauge) in the upper extremities (antecubital veins).
• If peripheral venous access cannot be obtained within 90 seconds in a patient with profound shock, immediately establish intraosseous (IO) access. The primary anatomical site is the proximal anteromedial tibia (approximately $2\text{ cm}$ distal and $1\text{ to }2\text{ cm}$ medial to the tibial tuberosity on the flat bony surface). The humeral head is an excellent alternative site in adults, delivering flow rates comparable to central venous lines.

Damage Control Resuscitation (DCR) & Permissive Hypotension

• The Pitfall of Crystalloid Over-Resuscitation: Historical protocols infusing 2 to 3 liters of cold normal saline or Ringer's lactate dilute clotting factors, strip the endothelial glycocalyx, produce hypothermia, worsen metabolic acidosis, and mechanically dislodge early fragile platelet plugs.
• Permissive Hypotension (Controlled Resuscitation): In actively bleeding trauma patients without head injury, clinicians deliberately restrict fluid administration, targeting a Systolic Blood Pressure (SBP) of 80 to 90 mmHg (Mean Arterial Pressure [MAP] 50 to 60 mmHg) until definitive surgical or angiographic hemostasis is achieved. This maintains sufficient vital organ perfusion while preventing the catastrophic dislodgement of hemostatic thrombi ("popping the clot").
• The Critical Traumatic Brain Injury (TBI) Exception:
  • In patients with confirmed or suspected TBI ($GCS \le 8$ or intracranial mass lesion), permissive hypotension is STRICTLY CONTRAINDICATED.
  • Injured brain parenchyma loses auto-regulatory vascular tone; cerebral blood flow becomes directly dependent on Mean Arterial Pressure ($CPP = MAP - ICP$). Even a single transient episode of hypotension ($SBP < 90\text{ mmHg}$) doubles mortality in severe TBI.
  • Target Hemodynamics in TBI: Maintain $SBP \ge 100\text{ mmHg}$ (in patients aged 50–69 years) or $\ge 110\text{ mmHg}$ (in patients aged 15–49 or $\ge 70$ years) to preserve a Cerebral Perfusion Pressure (CPP) of at least 60 to 70 mmHg.

Massive Transfusion Protocol (MTP): The PROPPR Trial

When a trauma patient presents with severe hemorrhagic shock (Assessment of Blood Consumption [ABC] score $\ge 2$: penetrating mechanism, positive FAST, $SBP \le 90\text{ mmHg}$, $HR \ge 120\text{ bpm}$), activate the Massive Transfusion Protocol immediately:

• Balanced Component Ratio (1:1:1): Deliver uncrossed blood components in a strict 1:1:1 ratio: 1 unit of Packed Red Blood Cells (PRBCs) : 1 unit of Fresh Frozen Plasma (FFP) : 1 unit of Platelets (typically dispensed as 6 units PRBCs, 6 units FFP, and 1 apheresis platelet pack).
• Evidence (PROPPR Trial): The Pragmatic Randomized Optimal Platelet and Plasma Ratios (PROPPR) trial demonstrated that resuscitation with a 1:1:1 ratio significantly reduced 24-hour exsanguination mortality and achieved anatomical hemostasis faster than an unbalanced 1:1:2 ratio.
• Adjunctive Hemostatic Targets:
  • Fibrinogen Replacement: Cryoprecipitate (10 to 20 units) or fibrinogen concentrate, targeting a serum fibrinogen level $> 150\text{ to }200\text{ mg/dL}$.
  • Ionized Calcium: Citrate preservative in stored blood products chelates free calcium, impairing cardiac contractility and clotting cascade complexes. Monitor ionized calcium ($iCa$) frequently and administer $1\text{ to }2\text{ g}$ IV Calcium Gluconate (or Calcium Chloride) for every 4 units of blood products, maintaining $iCa > 1.0\text{ mmol/L}$.

Tranexamic Acid (TXA): The CRASH-2 Trial

• Mechanism: Synthetic lysine analog that competitively inhibits plasminogen activation to plasmin, halting fibrin clot breakdown and stabilizing newly formed hemostatic seals.
• Dosing Protocol: $1\text{ g}$ IV bolus administered over 10 minutes, followed immediately by an intravenous infusion of $1\text{ g}$ over the subsequent 8 hours.
• The Strict 3-Hour Window (CRASH-2 Mandate):
  • TXA MUST BE ADMINISTERED WITHIN 3 HOURS OF INJURY.
  • When given within 1 hour, TXA reduces all-cause trauma mortality by $>30%$; between 1 and 3 hours, it delivers significant survival benefit.
  • administration beyond 3 hours post-injury Paradoxically INCREASES mortality (due to late hypercoagulability, microvascular thrombosis, and inflammatory shut-off) and is strictly contraindicated.

The Lethal Triad of Trauma

The primary physiological endpoint of modern damage control resuscitation is disrupting the self-propagating "Lethal Triad":

1. Hypothermia ($< 35.0^\circ\text{C}$): Dramatically inhibits the enzymatic reaction kinetics of the coagulation cascade; clotting factor activity decreases by $\sim 10%$ for every $1.0^\circ\text{C}$ drop in core body temperature.
2. Metabolic Lactic Acidosis ($pH < 7.20$, Base Deficit $> -6\text{ mEq/L}$): Caused by anaerobic cellular metabolism during tissue hypoperfusion; directly suppresses myocardial contractility, impairs vascular catecholamine responsiveness, and halts factor complex assembly.
3. Severe Coagulopathy: Triggered by consumption of clotting factors, hypothermia, acidemic enzyme inhibition, and hyperfibrinolysis.

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Extended Focused Assessment with Sonography for Trauma (E-FAST)

The E-FAST is a bedside point-of-care ultrasound (POCUS) examination performed during the Primary Survey to rapidly identify pathologic fluid collections (hemoperitoneum, hemothorax, hemopericardium) and pneumothorax in under 3 minutes.

The Six Sonographic Windows

1. Right Upper Quadrant (Morison's Pouch / Hepatorenal Recess):
   • Probe placed at the 8th to 11th intercostal space, mid-to-posterior axillary line.
   • The most sensitive dependent abdominal space for free intraperitoneal blood in the supine patient. Pathologic fluid collects as an anechoic (black) stripe between the liver and right kidney, or along the inferior liver tip.
2. Left Upper Quadrant (Splenorenal Recess & Subphrenic Space):
   • Probe placed at the 6th to 9th intercostal space, posterior axillary line.
   • Identifies free fluid between the spleen and left kidney, or in the subphrenic space above the spleen.
3. Pelvic Window (Suprapubic / Rectovesical or Rectouterine Pouch):
   • Transverse and sagittal views angled postero-inferiorly behind the pubic symphysis.
   • Evaluates the rectovesical pouch in males and the rectouterine pouch of Douglas in females. (An empty or catheterized bladder limits acoustic visualization).
4. Pericardial Window (Subxiphoid / Subcostal View):
   • Transducer placed flat in the subxiphoid region, pointing toward the left shoulder, using the left lobe of the liver as an acoustic window.
   • Identifies anechoic fluid separating the fibrous pericardium from the myocardium. Demonstrates right ventricular diastolic collapse in cardiac tamponade.
5. & 6. Bilateral Anterior Thoracic Windows (Pleural / Lung Evaluation):
   • High-frequency linear probe placed longitudinally across the 2nd to 4th intercostal spaces at the midclavicular lines.
   • Normal Lung: Displays shimmering, glistening horizontal "lung sliding" ("ants marching on a log") where visceral pleura glides over parietal pleura during respiration, accompanied by vertical reverberation comet-tail artifacts (B-lines). On M-mode, normal lung creates the "Seashore Sign" (linear motionless chest wall above; granular beach-like lung below).
   • Pneumothorax: Shows complete absence of lung sliding and absence of B-lines (presence of B-lines 100% excludes pneumothorax at that probe position). On M-mode, absent sliding displays the "Stratosphere / Barcode Sign" (uniform parallel horizontal lines across the entire display).
   • The Lung Point: The pathognomonic transition point where normal sliding lung intermittently alternates with absent sliding; possesses $100%$ specificity for pneumothorax, defining its exact anatomical boundary.

                         THE E-FAST CLINICAL TRIAGE DECISION TREE

                              Blunt Trauma Patient in Bay
                                           │
                                    Perform E-FAST
                                           │
                    ┌──────────────────────┴──────────────────────┐
                    ▼                                             ▼
       HEMODYNAMICALLY UNSTABLE                      HEMODYNAMICALLY STABLE
            (SBP <90 mmHg)                                (SBP ≥90 mmHg)
                    │                                             │
         ┌──────────┴──────────┐                       ┌──────────┴──────────┐
         ▼                     ▼                       ▼                     ▼
    POSITIVE FAST         NEGATIVE FAST           POSITIVE FAST         NEGATIVE FAST
   (Free fluid RUQ/      (No peritoneal          (Free fluid seen,     (No fluid or PTX)
     LUQ / Pelvis)         fluid seen)             patient stable)            │
         │                     │                       │                      ▼
         ▼                     ▼                       ▼              Selective Imaging /
    IMMEDIATE TO        Search for extra-        CONTRAST-ENHANCED       Serial Abdominal
   OPERATING ROOM       abdominal bleeding:       CT ABDOMEN/PELVIS         Exams in Bay
   FOR EXPLORATORY      • Unstable Pelvis?       (Grade solid organ
     LAPAROTOMY           (Apply binder)          injury, extravasation)
                        • Thoracic Hemorrhage?
                        • Retroperitoneal CT

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D — Disability (Neurological Evaluation)

• Glasgow Coma Scale (GCS): Standardized quantification of neurologic function:
  • Eye Opening (1 to 4): 4 = Spontaneous; 3 = To verbal command; 2 = To pain; 1 = None.
  • Verbal Response (1 to 5): 5 = Oriented; 4 = Confused; 3 = Inappropriate words; 2 = Incomprehensible sounds; 1 = None.
  • Motor Response (1 to 6): 6 = Obeys commands; 5 = Localizes pain; 4 = Withdraws from pain; 3 = Abnormal flexion (decorticate); 2 = Abnormal extension (decerebrate); 1 = None.
  • Severity Stratification: Severe TBI = GCS 3–8; Moderate TBI = GCS 9–12; Mild TBI = GCS 13–15.
• Pupillary Examination: Inspect baseline pupil size, symmetry, and light response. An acute unilateral dilated, non-reactive pupil ("blown pupil") indicates transtentorial uncal herniation compressing the ipsilateral oculomotor nerve (CN III), demanding immediate neurosurgical decompression and hyperosmolar therapy (hypertonic saline $3%$ or mannitol).

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E — Exposure & Environmental Control

• Complete Exposure: Remove all clothing with shears to visualize every square centimeter of the body. Missed posterior puncture wounds, axillary stab lacerations, perineal tears, and open extremity fractures occur when clothing is left partially attached.
• Log Roll & Spine Palpation: With the cervical spine rigidly maintained in neutral alignment by a designated team member at the head of the bed, a 4-person coordinated log roll is executed. Palpate the entire length of the spinous processes for step-offs, focal midline tenderness, or boggy hematomas. Inspect the gluteal fold, perineum, and back.
• Aggressive Hypothermia Prevention: Once exposure is complete, immediately apply pre-warmed blankets and forced-air warming devices (Bair Hugger), warm all infused intravenous fluids and blood components to $39.0^\circ\text{C to }42.0^\circ\text{C}$ via high-flow fluid warmers, and keep the trauma bay ambient temperature elevated ($\ge 26.0^\circ\text{C}$).

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The Secondary Survey & Radiographic Trauma Series

The Secondary Survey is initiated ONLY AFTER the Primary Survey has been fully executed, ABCDE life threats eliminated, and hemodynamic resuscitation actively established.

The AMPLE History

• A: Allergies
• M: Medications (especially anticoagulants: DOACs, warfarin, antiplatelet agents)
• P: Past medical history & Pregnancy status (all reproductive-age females require rapid urine/serum $\beta$-hCG)
• L: Last meal (time of last oral intake)
• E: Events & Environment preceding the traumatic injury

Physical Examination & Trauma Series Imaging

• Systematic Head-to-Toe Examination: Scalp lacerations, hemotympanum, Battle sign (mastoid ecchymosis), raccoon eyes (periorbital ecchymosis), facial bone stability, stability of the pelvis and all four extremities, distal pulses, and rectal exam (assessing rectal sphincter tone, mucosal integrity, and gross blood).
• Essential Plain Radiographs in Trauma Bay:
  1. Portable Anteroposterior (AP) Chest Radiograph: Screen for pneumothorax, hemothorax, mediastinal widening, and endotracheal tube depth.
  2. Portable AP Pelvis Radiograph: Detects pelvic ring disruptions, sacroiliac joint widening, and acetabular fractures.
• Definitive Diagnostic Imaging (Pan-Scan CT): In stable patients, high-resolution contrast-enhanced computed tomography (Non-contrast Head CT, Cervical Spine CT with sagittal/coronal reformats, and IV Contrast-Enhanced Chest, Abdomen, and Pelvis CT) represents the gold standard diagnostic series.