Prehospital Trauma Life Support — Master Summary

How this study guide works

This is a cumulative, high-yield reconstruction of the pages provided from Prehospital Trauma Life Support. It prioritizes clinical decisions, sequence of care, red flags, reasoning, and memorable examination points. Repetition and non-essential prose are consolidated as the guide grows. Every chapter has three layers: the core study summary (read it), the narrated lessons (listen to them), and the rapid review (test yourself). Picture-memory figures throughout are designed for visual recall. The source coverage map at the end shows exactly which source sections are covered where, so nothing disappears silently.

Summary status

• Manual sections processed: 1–117 (clinical content, summaries, questions, and answer keys); sections 118–150 are reference lists, intentionally omitted
• Chapters represented: All 9 learning chapters
• Coverage audited section-by-section against the source text; previously missed high-yield points are now integrated and every chapter has a recall block with the source study questions

Core study summary

1. Foundations of PHTLS

The central idea

PHTLS is not about blindly following one fixed recipe. It teaches you to combine:

1. Knowledge — understand anatomy, physiology, injury, and shock.
2. Critical thinking — adapt decisions to this patient, this scene, and the resources available.
3. Technical skill — perform necessary interventions effectively, even in poor conditions.

The purpose is simple: recognize what will kill the patient first, treat what can be treated now, and move rapidly toward definitive care.

The primary survey: XABCDE

flowchart TD
    S["Scene safety"] --> X["X — Exsanguinating hemorrhage"]
    X --> A["A — Airway"]
    A --> B["B — Breathing"]
    B --> C["C — Circulation"]
    C --> D["D — Disability / neurologic status"]
    D --> E["E — Exposure and environment"]

Memory anchor: X comes first because a patient can bleed to death before an airway procedure is completed. After scene safety, immediately control catastrophic external or junctional hemorrhage before moving to airway.

XABCDE is an order of priorities, not permission to stop thinking. Several team members may perform different actions simultaneously when resources allow.

Critical thinking loop

flowchart LR
    A["Assess"] --> P["Plan"]
    P --> D["Do"]
    D --> R["Reassess"]
    R --> A

At every stage, ask:

• Is the plan working?
• Has the patient’s condition changed?
• Have the scene, transport options, or available resources changed?
• Is an intervention worth the time and risk, or should it wait until transport?

Knowing when not to perform an intervention can be as important as knowing how to perform it.

Principles versus preferences

Memory anchor: Principle = destination. Preference = route. Preferences depend on patient condition, practitioner competence, equipment, circumstances, and local protocols.

Right patient, right destination, right transport, right time

Prehospital success is not measured by how many procedures are performed on scene. It means delivering the patient:

• to the right facility;
• using the right mode of transport;
• in the right amount of time;
• as safely as possible.

For a critically injured patient, perform essential lifesaving actions and avoid delays in reaching definitive trauma care.

The three phases of trauma care

EMS contributes to prevention as well as treatment. Home visits can reveal fall risks, and safe practice by responders protects the crew and patient.

The Golden Period

The old term Golden Hour does not mean every patient has exactly 60 minutes. The useful concept is a patient-specific Golden Period:

flowchart TD
    I["Injury occurs"] --> T["Time-sensitive threats progress"]
    T --> P["Essential prehospital actions"]
    P --> D["Definitive trauma care"]

• A penetrating cardiac injury may allow only minutes.
• Slow internal bleeding from an isolated fracture may allow much longer.
• The correct question is not “Are we inside one hour?” It is “What must happen before this patient’s physiology becomes irreversible?”

Therefore: minimize unnecessary scene time, coordinate the team, warn the receiving hospital early, and transport promptly to an appropriate trauma facility.

Communication is part of treatment

Trauma handover has three linked components:

1. Prearrival warning — allows the hospital to mobilize people and resources.
2. Verbal handover on arrival — transfers immediate clinical priorities.
3. Written patient care report — creates the complete clinical record.

Good trauma care is a continuum involving citizens, dispatch, police, fire services, EMS, hospitals, rehabilitation, primary care, researchers, and prevention services.

What matters from the statistics

Do not memorize every introductory number. Remember the pattern:

• Trauma is a major global cause of death, disability, and economic loss.
• Unintentional injury is especially important in younger people.
• Drowning and motor-vehicle collisions are prominent earlier in life.
• Falls become increasingly important with age and predominate in older adults.
• Motor-vehicle and fall deaths are expected to grow with increasing vehicle use and population aging.

The clinical lesson is that effective prevention, rapid hemorrhage control, shock care, and timely definitive treatment save both life and long-term function.

Numbers worth being able to quote: roughly 4.4 million people die of injury each year worldwide — nearly 8% of all deaths, more than tuberculosis, malaria, and HIV/AIDS combined produce in a year and a half. Unintentional injury is the leading cause of death between ages 1 and 45 and kills about 14,000 people per day. Unintentional falls were the number-one cause of nonfatal injury in the United States, and the leading risk factor for an injurious fall in an older adult is a previous fall. The economic impact of trauma in the United States is about $1.1 trillion a year; rapidly identifying life-threatening hemorrhage and transporting to a trauma centre saves society about $1.2 million per life in lifetime wage and productivity losses.

Preventing death across the trimodal pattern

Goals and origins

The three stated goals of PHTLS: reduce mortality and injury from trauma; give prehospital practitioners knowledge and skills; provide appropriate care to trauma patients. The science of medicine supplies the principles; the art of medicine supplies the preferences.

Exam-quotable history: ATLS began in 1978, prompted by a 1976 private plane crash in rural Nebraska involving an orthopedic surgeon’s family, and is the basis of PHTLS. Dr. Norman E. McSwain Jr. chaired the first ATLS ad hoc committee and drafted the PHTLS curriculum; PHTLS is now taught in more than 70 countries. The Golden Hour concept was conceived by R Adams Cowley in the late 1960s.

2. Assessment, hemorrhage control, and triage

The trauma approach

flowchart TD
    S["Scene safe?"] --> R["Resources and mechanism"]
    R --> X["XABCDE primary survey"]
    X --> C{"Critical patient?"}
    C -->|Yes| T["Essential treatment + rapid transport"]
    C -->|No| Q["Secondary survey"]
    T --> Q2["Complete assessment en route"]

Before touching the patient, assess hazards, violence, traffic, fire, electricity, hazardous materials, weather, bystanders, patient count, needed resources, and mechanism of injury. Scene assessment continues throughout the call. If the scene deteriorates, leave.

Form a general impression in seconds. A patient who answers “What happened?” coherently in full sentences probably has a patent airway, enough ventilation for speech, adequate cerebral perfusion, and reasonable neurologic function—but continue the survey.

The primary survey finds and treats immediate life threats. The secondary survey finds other injuries and may occur during transport. Do not delay definitive care to complete it on scene.

XABCDE essentials

• X: Find catastrophic compressible bleeding. Control it immediately.
• A: Open and clear the airway using the simplest effective method while protecting the cervical spine when indicated.
• B: Assess chest movement, air movement, rate, depth, effort, and bilateral breath sounds. Assist ventilation when inadequate and target oxygen saturation at least 94%.
• C: Assess pulse quality, skin colour, temperature and moisture, mental status, and obvious or hidden bleeding. Hypotension is a late sign.
• D: Rapid neurologic assessment: consciousness, pupils, movement, Glasgow Coma Scale when possible.
• E: Fully expose enough to find injuries, then prevent heat loss.

External hemorrhage: remember PRESS, PACK, TOURNIQUET

flowchart TD
    B["Severe external bleeding"] --> P["Focused direct pressure"]
    P --> W["Pack wound; hemostatic gauze preferred"]
    W --> C{"Controlled?"}
    C -->|No / exsanguinating limb| T["Tourniquet"]
    C -->|Yes| D["Secure pressure dressing"]

• Apply pressure precisely at the bleeding source. A gloved finger over a visible compressible artery can be very effective.
• Pack deep wounds. Maintain uninterrupted pressure according to the hemostatic product instructions, or approximately 10 minutes with plain gauze. Do not repeatedly lift the dressing to check.
• For life-threatening extremity bleeding, apply a commercial tourniquet immediately — instead of or concurrent with slower measures, never after they have been allowed to fail. The initial default is as proximal as possible — high and tight, near the groin or axilla — to gain control quickly. Placement 5–7.5 cm (2–3 inches) above the wound, never over a joint, is for when the bleeding site is readily and absolutely apparent. Tighten until bleeding stops and the distal pulse disappears; never loosen to “check.”
• Junctional bleeding cannot be controlled with a standard limb tourniquet: use a junctional device if available, or pack firmly with hemostatic gauze and apply pressure.
• Do not delay a tourniquet to try slower measures when arterial limb bleeding is immediately life threatening.

Capillary bleeding oozes and is usually minor. Venous blood usually flows steadily and dark red. Arterial bleeding may spurt or pour rapidly and is the greatest immediate threat—but treat the rate of blood loss, not merely its colour.

Hidden hemorrhage

Think of major internal blood loss in the chest, abdomen, pelvis, and thighs. It cannot be definitively stopped prehospital.

• Suspected unstable pelvic-ring injury: stop repeated palpation and apply a pelvic binder over the greater trochanters, not the waist.
• Splint fractures to reduce movement and vascular injury.
• Uncontrolled or suspected internal hemorrhage demands rapid trauma-centre transport.
• If no traumatic brain injury is suspected, support the minimum perfusion needed: roughly systolic pressure 80–90 mm Hg or restoration of a radial pulse and improved mentation. With suspected TBI, aim for at least 110 mm Hg.

Traumatic cardiac arrest

Treat reversible traumatic causes before copying a medical-arrest algorithm: control catastrophic hemorrhage, oxygenate and ventilate, decompress suspected tension pneumothorax, and address tamponade where the system permits. Chest compressions alone cannot refill an empty circulation or release obstructive pressure.

Follow local protocols for withholding or terminating resuscitation. Obviously fatal injury, decomposition, rigor, dependent lividity, or absent signs of life with non-survivable traumatic findings may justify withholding. Pregnancy, children, drowning, hypothermia, and lightning require special consideration.

Mass-casualty triage

The goal is the greatest good for the greatest number, not exhaustive treatment of the first critical patient. START rapidly assesses respiration, perfusion, and mental status; remember 30–2–can do. SALT means Sort, Assess, Lifesaving interventions, Treatment/transport.

During initial triage, only quick lifesaving actions are appropriate: open an airway, give a specific antidote, control external hemorrhage, or decompress a chest when indicated. Avoid tasks that trap the triage practitioner with one patient, such as prolonged bag-mask ventilation, cardiopulmonary resuscitation, intravenous access, or intubation.

A mass-casualty incident is defined as one in which the number of patients exceeds the capacity of the practitioners and their usual resources; triage is the process of assigning priority for treatment and transport.

Field triage: getting one patient to the right centre

The National Guideline for the Field Triage of Injured Patients (2021) drives everyday destination decisions:

• Red criteria — dangerous injury patterns or abnormal mental status/vital signs → transport to the highest-level trauma centre in the region.
• Yellow criteria — concerning mechanism of injury or EMS judgment → transport to a trauma centre.
• Over-triage (stable patient to a trauma centre) reduces efficiency; under-triage (critical patient to a non-trauma centre) reduces quality — under-triage is the dangerous error.
• The closest hospital able to manage uncontrolled bleeding or an unstable airway may not be a trauma centre — destination is its own decision.

Assessment pearls

• Hemorrhage is the most common cause of preventable death from trauma.
• Assume a confused, belligerent, combative, or uncooperative patient is hypoxic or brain-injured until proven otherwise — not intoxicated, not “difficult.”
• Decreased consciousness differential: reduced cerebral oxygenation or carbon-dioxide narcosis, central nervous system injury, drugs/alcohol/toxins, metabolic causes such as diabetes or seizure.
• GCS below 14 with an abnormal pupil exam can indicate life-threatening brain injury.
• Exsanguinating external sites include the scalp as well as limbs and junctions, and controlling X precedes even spinal motion restriction.
• The secondary survey is a head-to-toe exam performed only after the primary survey is complete and life threats are treated, with full vital signs and a SAMPLER history (Symptoms, Allergies, Medications, Past history, Last intake, Events, Risk factors).
• If a spinal immobilization device must be removed to reassess or intervene, reapply manual head and neck stabilization until it is restored.

Traumatic arrest decision points

• Arrest witnessed by EMS or within about 15 minutes of arrival: consider immediate transport with resuscitation en route.
• Consider terminating when the rhythm deteriorates to a nonviable one (for example, narrow-complex PEA becoming bradycardic wide-complex PEA) or resuscitation exceeds 15 minutes.
• Do not terminate with return of spontaneous circulation, organized PEA consistent with effective circulation, or a potential emergency-thoracotomy candidate (penetrating chest trauma with witnessed signs of life, or narrow-complex PEA at a normal or fast rate).
• Withholding rules differ: blunt trauma — no signs of life and no organized ECG rhythm; penetrating trauma — no pulse, breathing, movement, or pupillary response and no organized rhythm. “Obviously fatal” means injuries such as decapitation or exposed brain matter.
• If the mechanism seems too minor to explain the arrest, suspect a medical arrest that caused the trauma (for example, a myocardial infarction followed by a fall).

Special populations at a glance

Two more transport rules: if external hemorrhage cannot be controlled, begin rapid transport immediately — the patient will exsanguinate before any other threat kills; a traumatic amputation above the knee commonly has simultaneous intra-abdominal vascular injury. A pelvic binder works by “closing the open book”: restoring pelvic geometry lets pressure build inside the pelvic cavity and tamponade venous bleeding.

3. Airway

Airway anatomy in one picture

flowchart LR
    N["Nose / mouth"] --> P["Pharynx"]
    P --> L["Larynx + vocal cords"]
    L --> T["Trachea"]
    T --> B["Bronchi"]
    B --> A["Alveoli: gas exchange"]

The upper airway conducts, filters, warms, and humidifies air. The epiglottis protects the laryngeal opening during swallowing. The lower airway ends at the alveoli, where oxygen enters blood and carbon dioxide leaves it.

LOOK, LISTEN, FEEL

• Look: blood, vomit, teeth, dentures, swelling, facial or neck deformity, poor chest rise, retractions, paradoxical or seesaw movement.
• Listen: normal speech, snoring, gurgling, stridor, hoarseness, wheeze.
• Feel: air movement and structural abnormality where appropriate.

Normal full-sentence speech is reassuring. Hoarseness or stridor after neck trauma or inhalation injury suggests laryngeal compromise and possible rapid deterioration.

Escalate only as far as necessary

1. Position and manually open the airway: trauma jaw thrust or trauma chin lift.
2. Remove visible solids and use large-bore suction for blood or vomit. Prolonged suction can worsen hypoxia.
3. Provide bag-mask ventilation and oxygen if ventilation is absent or ineffective.
4. Use an adjunct suited to the patient.
5. Use a definitive airway only when its benefit outweighs failure, hypoxia, aspiration, circulatory collapse, and scene-time risks.

Before intubation, assess HEAVEN: Hypoxemia, Extremes of size, Anatomic challenge, Vomit/blood/fluid, Exsanguination, Neck restriction. Preoxygenate first. Confirm and continuously monitor tube placement with waveform capnography, and reconfirm after every move.

Children: large occiput and tongue plus a more anterior airway promote obstruction and neck flexion. Pad under the torso/shoulders — about 2–3 cm — not the head, to obtain neutral alignment. Bag-mask ventilate with high-flow oxygen at 15 L/min or more. Pediatric intubation is reserved for: a need for tightly controlled ventilation, impending obstruction, or insufficient resources for effective bag-mask ventilation — the child’s larynx is smaller, more anterior, and more cephalad, making the cords hard to see. Older adults: reduced reserve means earlier ventilatory support may be required; avoid forceful positioning of a stiff cervical spine.

Airway pearls examiners love

• Manual maneuvers have no contraindications in trauma. They can be used even with an intact gag reflex and are always the first move. The trauma jaw thrust is a single-practitioner technique (thumbs on the zygomas, fingers at the mandible angle); the trauma chin lift requires two practitioners.
• The tongue is the most common cause of upper-airway obstruction. It attaches to the mandible — that is why any maneuver that moves the mandible forward clears the hypopharynx.
• Suction technique: position or logroll the patient onto the side where possible, introduce the rigid catheter laterally (less stimulating), and hyperoxygenate once the airway is partially clear.
• The supraglottic airway can be placed in under 20 seconds and — its signature advantage — independent of patient position, which is why it is the answer for an apneic patient with suspected cervical injury or difficult access. Its esophageal seal stops passive regurgitation but cannot withstand active vomiting; avoid it after caustic ingestion or with known esophageal disease.
• An oral airway also serves as a bite block for an endotracheal tube.
• A “definitive” airway means the trachea is isolated from the esophagus by a seal below the vocal cords — the best aspiration protection, at the price of a high-risk procedure.
• If a basic maneuver manages the airway, stay with it. “A failed airway renders all other trauma care fruitless.”
• Older adults: leave intact dentures in place for a better mask seal, but remove dislodged or broken dentures. New confusion is hypoxia until proven otherwise — never attribute it to age. Fragile nasal mucosa plus anticoagulants make a nasal airway a bleeding (and aspiration) risk. Alveolar surface area falls about 4% per decade after age 30.

4. Breathing, ventilation, and thoracic trauma

Oxygenation is oxygen entering and being carried by blood. Ventilation is air moving in and out and carbon dioxide being cleared. A normal oxygen saturation does not prove adequate ventilation.

• Prioritize adequate tidal volume; minute ventilation equals rate × tidal volume.
• Target oxygen saturation above 94%, while treating the patient rather than a conflicting monitor.
• Pulse oximetry may be unreliable with motion, poor perfusion, edema, dirty sensors, or nail polish.
• End-tidal carbon dioxide confirms metabolism, circulation to the lungs, and alveolar ventilation. The manual’s normal reading is 30–40 mm Hg; the level to maintain during ventilation is 35–40 mm Hg.
• A sudden end-tidal carbon-dioxide drop may mean tube displacement or falling perfusion: reassess both patient and tube immediately.

Ventilation numbers that matter

• Normal tidal volume is about 500 mL, of which about 150 mL is dead space (mouth, pharynx, bronchi — no gas exchange). Minute volume at 14 breaths is 7,000 mL, but effective ventilation is only (500 − 150) × 14 = 4,900 mL/min — why shallow rapid breathing fails even when the rate looks adequate.
• 90% saturation is a cliff, not a number. Because of the hemoglobin-dissociation curve, oxygen delivery deteriorates very rapidly below 90% — it is not simply “100 minus 10.”
• Keep the patient on the lowest oxygen concentration that holds saturation above 94%; prolonged hyperoxia is also harmful.
• Capnography waveform: Phase I respiratory baseline, Phase II expiratory upstroke, Phase III alveolar plateau, Phase IV inspiratory downstroke. A waveform trending down suggests falling perfusion in shock; a slurred “shark-fin” upstroke suggests bronchospasm. A mainstream sensor sits between the bag device and the tube.

Drug-assisted intubation: three sequences

• Assume every trauma patient has a full stomach; elevating the head and thorax 30 degrees impedes gastric reflux.
• Evidence caveat: urban studies found critically injured patients intubated in the field did no better than those managed with bag-mask and an oral airway — the reason field intubation is labelled controversial.
• Intubated patients should be sedated for transport per protocol; sedation reduces work of breathing and “fighting the ventilator.”

Thoracic threats

For tension pneumothorax, this manual uses three combined findings: worsening respiratory distress or difficult bag-mask ventilation, unilateral decreased/absent breath sounds, and decompensated shock — defined here as systolic pressure below 90 mm Hg with a narrowed pulse pressure. Where needle decompression is permitted, it describes a 10–16 gauge catheter at least 8 cm long, preferably at the fifth intercostal space, anterior axillary line. This is temporary; reassess because tension may recur.

• Sealing a chest-wall hole does not stop air leaking from the injured lung itself — tension can still develop after a seal is applied (hence: briefly lift the seal if it does).
• Where no advanced practitioner is available, tension pneumothorax is managed with rapid transport and high-concentration oxygen; decompression may need repeating en route.
• Blunt deceleration can shear the great vessels — especially the aorta — causing catastrophic hemorrhage.
• Pediatric ribs are pliable: serious internal thoracic injury is more likely and can occur without any rib fracture.
• Cricothyrotomy goes through the cricothyroid membrane between thyroid and cricoid cartilage, located with the “laryngeal handshake”; a 2–3 cm vertical incision, and no second chance to get it right.

Longer or air transport lowers the threshold for securing an airway because access and reassessment become harder. The counterpoint: for a 15–20 minute transport, essential skills — an oral airway plus bag-mask ventilation — may be all the patient needs. Calculate oxygen supply before departure. Use continuous oximetry and mandatory capnography for an intubated patient.

5. Shock and resuscitation

Shock = inadequate cellular perfusion. Without oxygen, cells switch from efficient aerobic metabolism to low-output anaerobic metabolism, producing lactate and metabolic acidosis. Shock is “death in progress.”

flowchart TD
    H["Hemorrhage / pump failure / vasodilation"] --> P["Reduced tissue perfusion"]
    P --> A["Anaerobic metabolism"]
    A --> L["Lactate + acidosis"]
    L --> C["Cell and organ failure"]

Traumatic shock can involve:

• Fluid: hypovolemic/hemorrhagic shock—the most common.
• Pump: cardiogenic or obstructive causes such as tamponade and tension pneumothorax.
• Container: distributive shock, including neurogenic shock.

Do not wait for hypotension. Early clues include anxiety, restlessness, cool pale skin, delayed capillary refill, tachycardia, tachypnea, narrowing pulse pressure, and weakening peripheral pulses. Confusion, absent peripheral pulses, marked tachypnea, and falling pressure indicate progression.

The four classes of hemorrhage

A 70-kg (150-lb) adult circulates about 5 litres of blood.

The physiology in five numbers

• The body stores about 30 days of fat and 1 day of glucose but only about 5 minutes of oxygen — that is why shock is death in progress.
• Aerobic metabolism yields 38 ATP per glucose; anaerobic yields 2, plus lactic acid.
• Warm ischemia tolerance: heart, brain, lungs 4–6 minutes; kidneys, liver, gut 45–90 minutes; muscle, bone, skin 4–6 hours. In shock the body sacrifices kidneys, liver, lungs, bowel, and endothelium first and spares heart and brain until the end — organ damage precedes obvious vital-sign collapse.
• A single femur fracture can hide 1,000–2,000 mL in the thigh — up to 30–40% of blood volume and decompensated shock on its own.
• The initial platelet clot withstands only about 80 mm Hg — exceed it and you “pop the clot” and bleeding restarts. Major external bleeding can kill in about 3 minutes; a clot forms in about 3 minutes with hemostatic gauze versus up to 10 with plain gauze.

Medications that hide or worsen shock

• Beta blockers and pacemakers — block the compensatory tachycardia.
• Antihypertensives — block compensatory vasoconstriction.
• Diuretics — the patient starts hypovolemic.
• Anticoagulants — will need clotting-factor administration; antiplatelet agents — will need platelet transfusion. Ask about them and report them.
• Also concealing the pattern: pregnancy (blood volume up to 50% higher — major loss before overt signs), athletes (resting rate 30–40, so “90” may be compensatory tachycardia), children (compensate powerfully, then decompensate abruptly — a child in decompensated shock is a dire emergency), and older adults (a “normal” pressure may be relative hypotension against a hypertensive baseline).

Resuscitation priorities

1. Stop hemorrhage and correct obstructive causes.
2. Optimize oxygenation and ventilation.
3. Preserve the patient’s own blood; blood products are superior to crystalloid because they restore volume, oxygen-carrying capacity, and clotting components.
4. If blood is unavailable, give only enough crystalloid to restore minimal perfusion. Excess fluid dilutes clotting factors, worsens hypothermia, raises pressure, and may disrupt clot.
5. No suspected TBI: target radial pulse/improved mentation or systolic 80–90 mm Hg (a mean arterial pressure of about 65). The fluid trigger is systolic below 80 or an absent radial pulse. In penetrating trauma, delay aggressive fluids until definitive control — the goal of resuscitation is cellular perfusion, not a normal blood pressure.
6. Suspected TBI: systolic at least 110 mm Hg.
7. Keep the patient warm.
8. Transport rapidly for internal bleeding.

Colloids are not recommended prehospital; hypertonic saline exists in 7% and 3% forms; blood products (packed cells, whole blood, plasma, components) remain superior to everything else.

TXA is a lysine-analog antifibrinolytic — it stabilizes newly formed clots rather than substituting for hemorrhage control — with a useful anti-inflammatory effect. It is most useful early—within 3 hours—when transfusion is likely: hemorrhagic shock, elevated lactate, one or more major amputations, penetrating torso trauma, severe bleeding, and signs of significant traumatic brain injury (altered mental status with blunt or blast trauma). The tactical guidance quoted by the manual uses 2 g IV/IO slowly as a single dose; medication use must follow the applicable service protocol.

Remember the lethal triad: hypothermia + acidosis + coagulopathy. Each worsens the others: cells work within about one degree of 37 °C; cold increases oxygen demand (shivering) while disabling clotting.

6. Traumatic brain injury

Monro–Kellie doctrine

flowchart TD
    S["Rigid skull"] --> B["Brain"]
    S --> V["Blood"]
    S --> C["Cerebrospinal fluid"]
    M["New mass or swelling"] --> D["CSF and venous blood displaced"]
    D --> I["Compensation exhausted → ICP rises rapidly"]
    I --> H["Reduced perfusion and herniation"]

The volumes of brain, blood, and cerebrospinal fluid share a fixed cranial space. Early compensation can hide deterioration; once reserve is exhausted, intracranial pressure can rise steeply.

The chapter’s central formula: cerebral perfusion pressure = mean arterial pressure − intracranial pressure (CPP = MAP − ICP). You cannot measure ICP in the field, so maintain a high-normal MAP. A national TBI database found the two strongest predictors of poor outcome are time spent with ICP above 20 mm Hg and time spent with systolic pressure below 90 mm Hg. Severely injured brain regions also lose autoregulation: they dilate, steal flow from salvageable tissue, and aggressive hyperventilation compounds that ischemia.

Primary injury occurs at impact and cannot be reversed prehospital. Your job is to prevent secondary brain injury, particularly from hypoxia, hypotension, abnormal carbon dioxide, seizures, temperature extremes, or glucose derangement.

Targets that protect the brain

• Oxygen saturation: aim >94%, absolute floor 90%; never accept hypoxia (arterial oxygen below 50 mm Hg triggers cerebral vasodilation and raises ICP) — but prolonged hyperoxia is also harmful.
• Systolic blood pressure: aim >110 mm Hg.
• End-tidal carbon dioxide: 35–40 mm Hg, never below 30 unless brief controlled hyperventilation is indicated for clear herniation.
• Ventilatory rates: keep within 10–20 breaths/min — suggested adult 20, child 25, infant 30.
• Blood glucose: check every trauma patient; target 80–180 mg/dL in brain injury. Remember that hypoglycemia may have caused the crash or fall in the first place.
• Seizures rapidly deplete cerebral oxygen and glucose, compounding ischemia — ischemic tissue can trigger grand mal seizures or status epilepticus. Treat per protocol.
• Maintain normothermia and ensure the cervical collar does not obstruct jugular venous drainage.

Glasgow Coma Scale in bands

Report each of the three components numerically, note any untestable component, and score an intubated patient’s verbal response as “1T.” Moderate and severe TBI meet the Red criteria of the 2021 field-triage guideline: the highest-level trauma centre with CT, prompt neurosurgical consultation, and ICP monitoring. TBI patients may be combative with clenched jaws (trismus) and vomiting — plan the airway accordingly — and serious intracranial injury can exist with minimal or no external evidence of trauma.

Skull fractures

• Closed depressed fractures may need neurosurgery — encroaching bone raises ICP and underlying brain injury is common.
• Open fractures are an entry site for bacteria (meningitis risk); a torn dura may leak CSF or brain tissue. Both need immediate neurosurgical evaluation.

Hyperventilation lowers carbon dioxide and intracranial pressure by constricting cerebral vessels, but it also reduces cerebral blood flow. Reserve a target near 30 mm Hg for signs of herniation, not routine TBI care.

Pattern recognition—not field diagnosis

• Epidural: classically a low-velocity blow to the thin temporal bone tearing the middle meningeal artery; possible loss of consciousness → lucid interval → rapid decline; ipsilateral dilated pupil may appear.
• Subdural: torn bridging veins — more common than epidural; may be acute after major trauma, or chronic and subtle: brain atrophy in older adults enlarges the subdural space so blood accumulates without early mass effect, presenting late as headache, visual disturbance, personality change, dysarthria, or slowly progressive hemiparesis. Classic setting: an older, anticoagulated patient with a fall earlier in the week and worsening confusion.
• Subarachnoid hemorrhage: blood layers thinly under the arachnoid where the surface vessels lie, rarely causing mass effect; “worst headache of my life” (usually a spontaneous aneurysm rupture), neck stiffness, photophobia, nausea.
• Intracerebral hematoma: bleeding into functional brain tissue; may take days to develop — keep a high index of suspicion.
• Contusion/coup–contrecoup: brain bruising at impact and/or opposite side; takes 12–24 hours to appear on CT (the only clue may be a depressed GCS) and enlarges dramatically on anticoagulants or antiplatelet agents.
• Concussion: headache, dizziness, nausea, vomiting, cognitive or balance symptoms; normal initial imaging does not make symptoms trivial. Patients with concussion signs — especially vomiting or any neurologic finding — should be transported for evaluation. Postconcussion syndrome = symptoms beyond 1 month (normal recovery is 2–4 weeks), spanning vestibular, sensory, cognitive, and emotional domains.

Alcohol, unknown substances, hypoglycemia, or dementia can mask TBI — never let them rule it out when the mechanism is suspicious. Hypoxic events (drowning, hanging, asphyxiation) also injure the brain by swelling: any abnormal neurologic finding should trigger TBI suspicion.

Do not waste time trying to name the exact hematoma. Recognize TBI, trend Glasgow Coma Scale components, pupils, and motor asymmetry, prevent secondary injury, and transport moderate/severe TBI to the highest appropriate trauma centre with CT and neurosurgical capability.

Uncal herniation memory anchor: same-side blown pupil, opposite-side motor weakness, deteriorating consciousness and respiration.

7. Spinal trauma and motion restriction

Spinal motion restriction is selective, not automatic. Mechanism raises suspicion; examination and reliability determine the need.

Use restriction after blunt trauma when there is midline pain/tenderness, altered consciousness or intoxication, neurologic deficit, deformity, distracting injury, or inability to communicate. A reliable patient with GCS 15, no tenderness/deformity, no distracting injury, no intoxication, and no neurologic complaint may not need a backboard. Isolated penetrating trauma without neurologic deficit generally does not justify immobilization that delays care.

• Mechanisms that mandate manual stabilization and a spine assessment: violent impact to head, neck, torso, or pelvis; sudden acceleration, deceleration, or lateral bending; any fall — especially in an older adult; ejection or a fall from any powered transport device; any shallow-water incident (diving, body surfing). Significant helmet damage is a spinal red flag in its own right.
• Injury mechanisms on the column: axial loading (head strike, or landing standing after a fall), hyperflexion/hyperextension/excessive lateral bending, and distraction (longitudinal pull that stretches or tears the cord).
• Priapism is a sign of spinal cord injury.
• If the mechanism is unclear or the story unreliable, assume column injury until a proper assessment is possible.
• Repeat the rapid neurologic exam after immobilizing, after every patient movement, and on arrival.
• Unnecessary immobilization has documented harms — increased respiratory effort, skin ischemia, and pain, worse in older adults. An intermediate option, “spinal precautions,” is a rigid collar plus firm securing to the stretcher (no board) for ambulatory or reliable patients with mild-to-moderate neck pain.

How the cord fails: injury patterns

Complete injury = total bilateral loss of function below the level (a high cervical complete injury is often fatal before EMS arrives; swelling means the full extent cannot be judged for about 24 hours). Incomplete = any preserved motor or sensory function — better prognosis. The cord-injury spectrum runs concussion (temporary) → contusion (bruising; temporary or permanent) → compression (swelling, disc, bone, or hematoma — may need surgical decompression, so transport promptly) → laceration (usually irreversible).

Spinal versus neurogenic shock

Two clarifications: spinal shock usually resolves within 48 hours; and the manual itself attaches the phrase “hypotensive bradycardia” to spinal shock while conventional teaching (and the table above) files that hemodynamic pattern under neurogenic shock — know both framings for exams. In spinal cord injury, maintain a MAP of 85–90 mm Hg for the first 7 days using fluids through at least two large-bore IVs, and treat bradycardia with significant hypotension with atropine 0.5–1 mg IV. Narcotic analgesia can exaggerate neurogenic hypotension, and cord injury impairs thermoregulation — hypothermia risk in the cold, but over-bundling causes hyperthermia.

The diaphragm is supplied by C3, C4, C5—“C3, 4, 5 keep the diaphragm alive.” High cervical injury can rapidly cause ventilatory failure. In high injury, place securing straps at the shoulder girdle and pelvis and verify they do not limit chest excursion.

Manually stabilize in neutral alignment. Stop repositioning if it causes resistance, spasm, increased pain, neurologic deterioration, or airway/ventilation compromise. Secure torso first, then head (then legs, then pelvis), and pad voids. Fractures at one level are often accompanied by fractures at other levels — treat the whole weight-bearing spine as one entity. A scoop stretcher or vacuum mattress is often preferable to prolonged rigid-board use; the manual advises avoiding a rigid backboard beyond about 30 minutes where possible.

Common motion-restriction errors: an improperly sized or applied collar; securing the head before the torso (or readjusting torso straps afterward); inadequate void padding; immobilizing patients who do not meet criteria; taking excessive time in an unstable patient; and strapping so aggressively that the airway or ventilation is compromised. If the supine immobilized patient vomits, tip the board and patient onto the side immediately and keep suction at the head.

Special positioning: pad beneath a child’s shoulders/torso (prevents hyperflexion from the large occiput); an adult instead gets firm padding behind the head to prevent hyperextension. Support an older adult’s natural kyphosis rather than forcing flat alignment — cervical osteoarthritis means airway positioning alone can injure the cord, and severe kyphosis may need a rolled towel plus head blocks instead of a collar that would compress the airway or carotids. Tilt a pregnant patient left; monitor bariatric patients closely for supine ventilatory compromise.

8. Exposure, environment, and burns

Expose sufficiently to find injuries—then cover immediately. The aphorism: the one part not exposed will be the most severely injured. Wet clothes, cold ground, airflow, young or old age, and shock accelerate heat loss — heat is lost whenever ambient temperature is below 37 °C, and damp clothing pulls it away by conduction. Protect privacy and dignity without allowing an unseen injury to remain hidden.

• Clothing rules: make as few cuts as possible; undergarments can usually stay unless a genital exam, pelvic binder, or catheter is needed — but remove a bra when managing chest injuries. Exposure also confirms splints are not applied over clothing. Preserve evidence at crime scenes.
• Older adults: look for medical-alert tags and medication patches — patients may wear several stacked patches; remove them, they impair compensation. Hypothermia risk from low metabolism, little body fat, and poor vasoconstriction; hyperthermia risk from diuretics, antihistamines, and antiparkinsonian drugs. Fragile skin: early dressing and pressure-area care.
• Children: immature thermoregulation, high surface-to-mass ratio, and no effective shivering — place warm blankets under and over the child. For a stable toddler, use a “toe-to-head” exam with a parent present.
• Bariatric patients: a standard longboard is only about 40–43 cm wide; verify device weight ratings; supine positioning itself can cause ventilatory failure from adipose pressure on the diaphragm.

Burn depth

Stop the burning with copious room-temperature water. Remove hot clothing and jewellery, but do not pull off material melted into skin. Never apply ice: it eases pain briefly while vasoconstriction kills additional tissue in the zone of stasis — the salvageable ring around the burn. Cover with sterile non-adherent dry material (a commercial hydrogel dressing can cool and cover) and keep the patient warm; dressings also stop the severe pain of air moving over exposed nerve endings. Avoid creams or topical antibiotics — the burn centre scrubs them all off.

Depth pearls: intact sensation to touch distinguishes deep partial-thickness from full-thickness — anything short of full thickness hurts significantly. Depth is deceptive and evolves; in the field say only “superficial versus deep.” Full-thickness burns belong at a burn centre for early excision; circumferential full-thickness burns may need escharotomy, and burned limbs should be elevated during transport to limit edema.

For small burns, the patient’s whole palm including fingers approximates 1% TBSA (precisely: palm alone ~0.5%, palm plus fingers ~0.8%, slightly less in women, and less as BMI rises). In adults, use the rule of nines; genital/perineal area is 1%. Burns of hands, feet, face/airway, genitalia, circumferential burns, and substantial deep burns warrant burn-centre consideration.

For deep partial/full-thickness burns over 20% TBSA, the manual teaches the Parkland estimate — using lactated Ringer (normal saline in these volumes causes hyperchloremic metabolic acidosis):

24-hour fluid = 4 mL × weight in kg × %TBSA

Give half during the first 8 hours from the time of injury, and the other half over the next 16 hours. Burn resuscitation replaces losses already incurred plus anticipated capillary leak over 24 hours — a different logic from hemorrhage replacement. Urine output is the primary endpoint: monitor it closely above 20% TBSA and place a catheter for hourly measurement above 40%. Avoid boluses unless the patient is hypotensive — titrate the calculated rate instead.

Burn analgesia: use the IV route (intramuscular and oral absorption are unreliable after severe burns); opioids first, and ketamine 0.5 mg/kg hourly can augment analgesia while sparing narcotics.

Burns that say “abuse”

• Forcible immersion is the most common abuse burn: glove or stocking patterns on hands or feet, symmetric burns, sharp lines of demarcation (“dip lines”), and no splash marks.
• Spared flexion creases (behind knees, inside elbows, groin) — the child flexes defensively in hot water.
• Clearly defined edges or object imprints: cigarette, iron.
• Contrast with a genuine accident: a hot-liquid spill hits the head, trunk, and palmar surfaces with an irregular splash pattern.

9. Pain, abdominal, obstetric, and musculoskeletal trauma

Pain

Pain is the “fifth vital sign” and its management is a Golden Principle of PHTLS. Believe and assess the patient’s report — 0–10 scale in adults, FLACC or Wong-Baker FACES scales in children. The myth that analgesia masks trauma assessment has been disproven. Combine explanation, calm positioning, breathing/distraction, splinting, traction where appropriate, and cold packs with medication when indicated. Nonopioids (acetaminophen/NSAIDs, which are synergistic) are first line for mild-to-moderate pain — but NSAIDs are contraindicated in pregnancy (miscarriage risk early, premature ductus closure late).

• Fentanyl — often favoured for severe trauma pain: rapid onset (intranasal/intramuscular under 10 minutes), short duration (30–60 minutes), least hemodynamic effect. Caution: rapid pushes can cause chest-wall rigidity.
• Morphine — 0.1 mg/kg, lasts 2–3 hours; hypotension risk comes from profound histamine release.
• Ketamine — an NMDA-receptor antagonist; analgesic dosing preserves respiratory drive and pressure; adverse effects include hypertension and tachycardia; patients who have taken stimulants, alcohol, or opioids are more likely to need intubation after ketamine.

Medication choice and dosing follow local protocol and patient physiology.

Abdominal trauma

Unexplained hypovolemic shock after trauma is internal bleeding until proven otherwise. Solid organs and vessels bleed; hollow organs leak contents and cause peritonitis/sepsis. The abdomen can hide a large volume without early distension.

• Inspect for wounds, bruising, distension, seat-belt sign, evisceration, or impaled objects. A seat-belt sign raises the likelihood of intra-abdominal injury eightfold — and even more in children.
• Injury patterns worth knowing: driver-side impact → suspect spleen; passenger-side → liver. Stab wounds most often injure liver, small bowel, and diaphragm; gunshot wounds small bowel, colon, and liver. Primary blast injures hollow organs (bowel-wall damage with delayed perforation); tertiary blast lacerates solid organs.
• Palpate gently, starting away from pain. Involuntary rigidity suggests peritoneal irritation. Pelvic palpation is unnecessary prehospital — if done, only once (repeat springing dislodges clots).
• Grey-Turner (flank) and Cullen (periumbilical) bruising indicate retroperitoneal bleeding — both are late findings.
• Do not remove an impaled object; stabilize it (apply pressure around it if it must be cut free).
• Do not replace eviscerated organs. Cover them with saline-moistened sterile dressing, then an outer dry/occlusive layer to conserve heat. Keep the patient calm — crying and coughing force out more viscera.
• Suspected internal bleeding needs rapid surgical-capable transport and balanced pressure targets: 80–90 mm Hg without TBI; ≥110 mm Hg with TBI.

Pregnancy

Pregnancy increases blood volume by up to 50%, so a pregnant patient can lose 1,200–1,500 mL before showing signs of hypovolemia — while the fetus is already hypoperfused. Motor vehicles cause half of traumatic injuries in pregnancy and 82% of trauma-related fetal deaths (mostly improper seat-belt use); pelvic fracture is the most common maternal injury leading to fetal death. Displace the uterus left—left lateral tilt, manual displacement, or elevating the right leg—to relieve inferior vena-cava compression (a third-trimester problem: the fundus reaches the umbilicus by 20 weeks and the xiphoid by 38). Prioritize maternal resuscitation because fetal perfusion depends on it. Unlike ordinary permissive hypotension, restore normal maternal pressure to support the fetus — accepting the bleeding risk. Transport to trauma care with obstetric and surgical capacity where possible.

Suspect abruptio placentae — whose most common cause is trauma, even a minor collision or fall — with a firm, hard, tender uterus; vaginal bleeding is visible in only 70% of cases, so its absence excludes nothing. Do not waste time seeking fetal heart tones — it changes no field management; ask instead about contractions (premature labour) and decreased fetal movement (fetal distress).

In traumatic arrest at 24 weeks or more, notify the receiving team early for possible resuscitative caesarean delivery; the manual emphasizes a goal within 5 minutes of arrest. Continue left uterine displacement during resuscitation.

Musculoskeletal trauma

Do not let a dramatic deformity distract from XABCDE. Femur, pelvis, mangled limb, and partial amputation can cause fatal hemorrhage.

• Examine pulse, movement, sensation, colour, and capillary refill before and after splinting.
• Immobilize the joint/bone above and below a long-bone injury; pad and remove constricting jewellery.
• If a deformed limb is pulseless, make one gentle alignment attempt per protocol, then reassess and splint. For a deformed but perfused extremity, make no more than two realignment attempts; if unsuccessful, splint as found and document any bone ends that retract into the wound.
• Dislocations: splint in the position found; manipulate a joint only for an absent or weak pulse, per protocol, by trained practitioners — with a short transport, transport instead.
• Pelvic binder: centre over greater trochanters. Its purpose is reducing blood loss, not stabilizing the fracture, and the classic error is placing it too high, over the pelvic brim. Pelvic fractures travel with TBI, thoracic and long-bone injuries, spleen, liver, and kidney injury, and urethral disruption in men.
• Midshaft femur: traction splint when indicated; avoid with ipsilateral foot/ankle avulsion or amputation, or an adjacent knee fracture.
• Compartment syndrome: pain out of proportion and sensory change occur early; pallor, paralysis, and absent pulse are late. Two causes: bleeding into a compartment, or reperfusion edema. Loosen external constriction, avoid elevation, and transport for surgical decompression.
• Amputations: partial amputations bleed more than complete ones — fully transected arteries retract and constrict; partially cut vessels cannot. Rinse the part gently (lactated Ringer), wrap in moistened sterile gauze, seal in a labelled bag, place that bag in a container with crushed ice. Do not place tissue directly on ice and do not delay the patient while searching — police can bring the part later. Replantation priorities are the thumb and upper extremity; lower-extremity parts are generally not replanted. A mangled extremity means hemorrhage control and a Level I trauma centre.

Crush injury and crush syndrome

Prolonged compression causes rhabdomyolysis; releasing it floods the circulation with potassium and acid and can trigger arrest at the moment of reperfusion. Begin resuscitation before extrication:

• Normal saline 1,500 mL/hr before release, targeting urine output of 150–200 mL/hr. Avoid lactated Ringer — it contains potassium — until urine output is adequate. Some protocols add 50 mEq sodium bicarbonate and 10 g mannitol per litre. After extrication, reduce to about 500 mL/hr alternating with dextrose 5%.
• Watch the monitor for peaked T waves — hyperkalemia. Treat per protocol with IV sodium bicarbonate, inhaled albuterol, dextrose plus insulin, and IV calcium chloride for life-threatening dysrhythmias.

TTS listening script

Lesson 1 — How PHTLS wants you to think

Prehospital Trauma Life Support is not a collection of procedures to perform automatically. [Pause]

It is a way of deciding what matters most… for this patient… at this moment. [Pause]

Three things support excellent trauma care. Knowledge. Critical thinking. And technical skill. [Pause]

The practical objective is straightforward: identify what can kill the patient first, correct immediately reversible threats, and move the patient toward definitive care without avoidable delay. [Long pause]

The primary survey is remembered as X, A, B, C, D, E. [Pause]

First, ensure scene safety. Then X: exsanguinating hemorrhage. This means catastrophic bleeding. Control it immediately. [Pause]

Next, A: airway. B: breathing. C: circulation. D: disability, meaning rapid neurologic assessment. And E: exposure, while protecting the patient from environmental harm. [Long pause]

Why does X come before airway? Because catastrophic external bleeding can kill within minutes, sometimes before an airway procedure is finished. [Pause]

Now remember the critical-thinking loop. Assess. Plan. Act. Reassess. Then adjust. [Pause]

Do not continue an ineffective plan merely because it was your first plan. The patient’s physiology decides whether the plan is working. [Long pause]

PHTLS also distinguishes principles from preferences. A principle is the physiological result that must be achieved. A preference is the particular method used to achieve it. [Pause]

Think of it this way. The principle is the destination. The preference is the route. [Pause]

For example, oxygen must reach the alveoli through an open airway. That is the principle. Whether the patient maintains the airway or needs a particular adjunct is the preference. [Long pause]

Finally, forget the idea that every trauma patient has a literal golden hour. Each patient has a different golden period. A cardiac stab wound may allow only minutes. Slow internal bleeding may allow considerably longer. [Pause]

Your question is: how quickly is this patient’s condition becoming irreversible… and what truly must be done before transport? [Pause]

Perform essential lifesaving care. Avoid low-value delay. Alert the hospital. And get the patient to the right facility, by the right transport method, in the right amount of time, as safely as possible.

Lesson 2 — Assessment, hemorrhage control, and triage

Begin with the scene. [Pause] If the scene is unsafe, you do not have a patient yet. You have a hazard. Look for traffic, violence, fire, electricity, hazardous substances, unstable structures, weather, and people whose behaviour is changing. Decide whether you need more resources and keep an exit route. [Long pause]

Now approach the patient using X, A, B, C, D, E. X means catastrophic hemorrhage. Press directly on the source. Pack a deep wound. For immediately life-threatening limb bleeding, apply a tourniquet. Tighten until bleeding stops and the distal pulse is gone. Do not loosen it to see whether the bleeding has stopped. [Pause]

Think of hidden blood in four large spaces: chest, abdomen, pelvis, and thighs. You cannot stop major internal hemorrhage in the ambulance. Recognize it, support minimum perfusion, prevent hypothermia, and move toward surgery. [Long pause]

Where should the tourniquet go? The initial default is high and tight, as proximal as possible. Placing it a few centimetres above the wound is reserved for when the bleeding site is absolutely apparent. [Pause]

Remember why hemorrhage matters so much: bleeding is the most common cause of preventable death from trauma. [Pause]

A confused, combative, or uncooperative patient is hypoxic or brain injured until proven otherwise. Never write that behaviour off as intoxication. And a Glasgow score below fourteen, combined with an abnormal pupil, can mean life-threatening brain injury. [Long pause]

For destination, think in colours. Red criteria — dangerous injury patterns, or abnormal vital signs and mental status — go to the highest-level trauma centre in the region. Yellow criteria — a worrying mechanism, or your own judgment — go to a trauma centre. Under-triage is the dangerous error, because a critical patient lands somewhere that cannot save them. [Pause]

In traumatic cardiac arrest, treat what is reversible. If the arrest happened within about fifteen minutes, or you witnessed it, consider immediate transport with resuscitation en route. And if the mechanism seems too trivial to explain an arrest, suspect that a medical arrest caused the trauma. [Long pause]

Lesson 3 — Airway

Next is airway. Start simple. Position. Jaw thrust. Chin lift. Remove visible material. Suction blood or vomit. Ventilate with a bag and mask if the patient’s effort is absent or ineffective. Then select an adjunct based on this patient, not on which device appears most advanced. [Pause]

Manual maneuvers have no contraindications in trauma. None. They work even with an intact gag reflex, and they are always the first move. The tongue is the most common obstruction, and it hangs from the mandible — that is why pushing the jaw forward clears the throat. [Pause]

An oral airway is for an unconscious patient without a gag reflex. A nasal airway may be tolerated when consciousness remains, but use caution with possible basilar skull fracture. A supraglottic airway is rapid and useful, but does not completely protect against aspiration and will not bypass swelling at the larynx. Endotracheal intubation can be definitive, but repeated attempts cause hypoxia and waste time. [Pause]

Before intubation, remember HEAVEN. Hypoxemia. Extremes of size. Anatomic difficulty. Vomit, blood, or fluid. Exsanguination. And neck restriction. Preoxygenate first. Confirm placement with waveform capnography, and check it again every time the patient moves. [Long pause]

Two pearls before we move on. The supraglottic airway can be placed in under twenty seconds, and it goes in regardless of patient position — which is why it is the answer for an apneic patient with a suspected neck injury. [Pause]

And in older adults: leave intact dentures in for a better mask seal, remove broken ones. If an older patient becomes confused, that is hypoxia until proven otherwise — never blame age. If a basic maneuver is managing the airway, stay with it. A failed airway renders everything else you do fruitless. [Long pause]

Lesson 4 — Breathing and the chest

Breathing is more than oxygen saturation. Oxygenation tells you how much hemoglobin is carrying oxygen. Ventilation tells you whether air is moving and carbon dioxide is leaving. A patient can have a reassuring saturation and still ventilate badly. Watch chest rise. Feel air movement. Listen bilaterally. Judge rate, depth, and effort. [Pause]

Here is the arithmetic that makes shallow breathing dangerous. Of a normal five hundred millilitre breath, about one hundred and fifty millilitres never reach the alveoli. That is dead space. A patient breathing fast and shallow can move plenty of air and still exchange almost nothing. [Pause]

And treat ninety percent saturation as a cliff edge. Below ninety, oxygen delivery does not decline gently — it falls away steeply. [Long pause]

Suspect tension pneumothorax when three things converge: worsening respiratory distress or difficult bag-mask ventilation… reduced or absent breath sounds on one side… and decompensated shock. This is an obstructive problem. Fluids alone do not release the pressure. Decompression, when permitted and indicated, is lifesaving—but temporary. Reassess because tension can return. [Long pause]

An open chest wound gets a vented seal, or a dressing taped on three sides so air can escape as the patient exhales. But remember: sealing the hole in the chest wall does not seal the hole in the lung. Tension can still build behind your dressing — if it does, lift the seal. [Pause]

If drugs are used to facilitate intubation, know the three roads. Sedation alone keeps the patient breathing. Rapid sequence adds a paralytic to prevent aspiration, and gambles on your preoxygenation. Delayed sequence uses sedation to make preoxygenation possible first. Every trauma patient has a full stomach — raise the head and chest thirty degrees. [Long pause]

Lesson 5 — Shock and resuscitation

Shock means inadequate cellular perfusion. The common trauma cause is hemorrhage, but the pump can fail and the vascular container can dilate. Never wait for low blood pressure. Anxiety, restlessness, cool pale skin, delayed refill, tachycardia, tachypnea, and narrowing pulse pressure warn you earlier. [Pause]

The body holds about five litres of blood, and it hides its losses in four stages. Class one, up to fifteen percent: almost nothing to see. Class two, up to thirty percent: the trap — a narrowing pulse pressure with a normal systolic. Class three: confusion, and pressure finally falling. Class four, beyond forty percent: barely rousable, systolic near sixty, dying. Hypotension is a late sign — say it again — hypotension is a late sign. [Long pause]

One femur can pour up to two litres into the thigh. And the fresh platelet clot tolerates a pressure of only about eighty millimeters of mercury. Push the pressure higher with fluid and you pop the clot, and the bleeding starts again. That is why we titrate, not flood. [Pause]

Ask about medications. Beta blockers hide the tachycardia. Antihypertensives block the vasoconstriction. Diuretics mean the tank started low. Anticoagulants and antiplatelet drugs mean the hospital must reverse something — tell them early. [Long pause]

Stop bleeding first. Blood is the best replacement for blood. If only crystalloid is available, give the least amount that restores useful perfusion. Without suspected brain injury, aim for a radial pulse, improving mentation, or a systolic pressure around eighty to ninety. With suspected traumatic brain injury, protect cerebral perfusion and aim for at least one hundred and ten. [Pause]

Keep the patient warm. Hypothermia worsens clotting. Acidosis worsens function. Coagulopathy worsens bleeding. Together, they form the lethal triad. [Pause]

Tranexamic acid stabilizes clots that already exist. Think of it early — within three hours — for hemorrhagic shock, penetrating torso trauma, major amputation, or significant brain injury, always under your protocol. [Long pause]

Lesson 6 — Traumatic brain injury

Now picture the skull as a rigid box holding three things: brain, blood, and cerebrospinal fluid. When a hematoma or swelling adds volume, cerebrospinal fluid and venous blood are displaced at first. The patient may appear stable. When that reserve is exhausted, intracranial pressure rises rapidly, blood flow falls, and herniation follows. [Pause]

One formula rules this chapter. Cerebral perfusion pressure equals mean arterial pressure minus intracranial pressure. You cannot measure the intracranial pressure, so defend the arterial pressure. The two strongest predictors of a bad outcome are time spent with intracranial pressure high, and time spent with systolic pressure below ninety. [Long pause]

Grade the Glasgow scale in bands. Thirteen to fifteen is mild. Nine to twelve is moderate. Three to eight is severe. Report each component as a number, and if the patient is intubated, the verbal score is one, T. [Pause]

You cannot reverse the primary brain injury in the field. You can prevent secondary injury. Maintain oxygen saturation above ninety-four percent. Maintain systolic pressure above one hundred and ten. Keep end-tidal carbon dioxide between thirty-five and forty. Check glucose. Maintain normal temperature. [Pause]

Do not routinely hyperventilate brain-injured patients. Lower carbon dioxide constricts cerebral vessels and can starve threatened tissue. Brief controlled hyperventilation toward thirty is reserved for clear herniation. Remember the uncal pattern: a blown pupil on the same side… weakness on the opposite side… and worsening consciousness and breathing. [Pause]

Hold one clinical picture in your mind: an older patient on a blood thinner, a fall earlier in the week, and confusion that has crept in over a day. That is a subdural hematoma until a scanner says otherwise. And remember that alcohol, low blood sugar, and dementia can each mask a brain injury — they never rule one out. [Long pause]

Lesson 7 — Spinal trauma

For the spine, mechanism creates suspicion, but examination determines restriction. Midline tenderness, neurologic deficit, intoxication, altered consciousness, deformity, distracting injury, or unreliable communication support spinal motion restriction after blunt trauma. Do not force every patient onto a rigid board. [Pause]

Certain mechanisms demand your hands on the head: any fall in an older adult, any shallow-water diving incident, ejection from any powered device, and a helmet that is significantly damaged. A broken helmet means the head hit hard. [Pause]

Spinal shock is loss of motor, sensory, and reflex function below the injury. Neurogenic shock is loss of sympathetic vascular tone, producing hypotension with relative bradycardia and warm skin. Hemorrhagic shock more often produces tachycardia with cool clammy skin. [Pause]

Stabilize neutral alignment, but stop if movement causes resistance, spasm, more pain, neurologic change, or airway compromise. Secure the torso before the head. And remember: cervical levels three, four, and five keep the diaphragm alive. [Pause]

Three incomplete cord patterns are worth naming. Anterior cord: motor and pain sense are lost, but position and vibration survive. Central cord: the arms are weaker than the legs, often after a hyperextended neck. Brown-Séquard, the hemisection: same-side motor loss, opposite-side pain and temperature loss. [Pause]

For a confirmed cord injury, keep the mean arterial pressure at eighty-five to ninety. If the heart slows and the pressure falls, atropine is the drug. And if the strapped-down patient vomits, tip the whole board on its side without hesitation. [Long pause]

Lesson 8 — Exposure, environment, and burns

Exposure means finding what clothing conceals, then preventing heat loss. Cut or remove enough clothing to assess properly. Respect privacy. Remove wet material. Cover the patient again and warm the ambulance for the patient, not for the crew. The part you never exposed is the part that will surprise you. [Pause]

For burns, first stop the burning process with room-temperature water. Remove hot clothing and jewellery unless material is melted into the skin. Never use ice. Ice may reduce pain briefly while vasoconstriction deepens tissue injury. Cover with clean, dry, non-adherent material and keep the patient warm. [Pause]

Superficial burns are red and painful without blisters. Partial-thickness burns are wet, blistered, and very painful. Full-thickness burns are dry, leathery, white or charred, and may be insensate centrally. Do not rupture intact blisters in the field. Circumferential chest burns can restrict ventilation; circumferential limb burns can threaten perfusion. [Pause]

For large deep burns, the Parkland estimate is four millilitres, times kilograms, times percent of body surface burned, over twenty-four hours — half in the first eight hours from the time of injury. Use lactated Ringer, and steer by urine output rather than boluses. [Pause]

And keep one protective instinct switched on: burns can be inflicted. Glove or stocking patterns, sharp dip lines, symmetric burns without splash marks, spared creases behind the knees and elbows, or the printed shape of an object — those patterns say abuse. An accidental spill splashes irregularly across the head, trunk, and palms. [Long pause]

Lesson 9 — Pain, abdomen, pregnancy, and limbs

Finally, do not let pain or a dramatic limb deformity create tunnel vision. Treat pain, but keep the whole patient in view. Unexplained shock may be abdominal hemorrhage. A seat-belt bruise multiplies the odds of internal injury eightfold. Do not remove impaled objects. Do not push eviscerated organs back inside. Cover them with saline-moistened sterile dressing and protect body heat. [Pause]

In pregnancy, move the uterus left to improve venous return. Resuscitate the mother aggressively enough to restore fetal perfusion — she can lose a litre and a half of blood before showing you anything. A firm, hard, tender uterus means placental abruption, and in three cases out of ten there is no visible bleeding at all. Do not chase fetal heart tones; ask about contractions and fetal movement. [Pause]

Trapped and crushed patients are a chemistry problem. Start fluid before the weight comes off — normal saline, not lactated Ringer — because releasing the compression releases potassium and acid, and reperfusion can stop the heart. Peaked T waves on the monitor mean the potassium is winning: bicarbonate, albuterol, dextrose with insulin, and calcium chloride for a dying rhythm. [Long pause]

One amputation paradox to keep: a partial amputation bleeds more than a complete one, because a fully cut artery retracts and clamps itself shut, and a partly cut artery cannot. [Pause]

For limb injuries, assess pulse, movement, sensation, and colour before and after splinting. A pelvic binder belongs over the greater trochanters. Pain out of proportion can signal compartment syndrome before the pulse disappears. An amputated part is wrapped moist, sealed in a bag, and kept cool beside ice—never directly on it. [Long pause]

The final memory is simple. Safety first. Stop catastrophic bleeding. Protect oxygenation and ventilation. Preserve perfusion. Prevent secondary injury. Keep the patient warm. Reassess after every action. And do not allow a procedure to delay the definitive care the patient actually needs.

Rapid review and recall

Chapter 1 recall

1. What comes first after scene safety?
   Control of exsanguinating external or junctional hemorrhage — the X in XABCDE.

2. What is the critical-thinking cycle?
   Assess → plan → act → reassess → adjust.

3. What is the difference between a principle and a preference?
   A principle is the required physiological goal; a preference is the situation-dependent method used to reach it.

4. Is the Golden Hour literally 60 minutes?
   No. The Golden Period varies with the injury and rate of physiological deterioration.

5. What are the three phases of trauma care?
   Pre-event, event, and post-event.

6. What are the three parts of trauma communication?
   Prearrival warning, verbal arrival report, and written patient care report.

7. What should determine an intervention?
   Patient assessment, likely benefit versus cost or delay, practitioner skill, resources, circumstances, and local protocol.

Common traps

• Starting airway management while obvious catastrophic bleeding remains uncontrolled.
• Treating the Golden Hour as a stopwatch with the same limit for every injury.
• Performing every possible on-scene intervention instead of prioritizing transport.
• Confusing a preferred technique with the underlying physiological principle.
• Failing to reassess after an intervention.

Source study-question answers

1. Critical thinking process — develop, initiate, reassess, and adjust the plan.
2. Controlling severe bleeding from a limb or another compressible site — X precedes everything after scene safety.
3. Principles — the science of medicine defines what must be achieved to maximize survival.
4. Expedite field care and transport — the goal of the Golden Period is minimizing time from injury to definitive care.

Chapter 2 recall

1. Arriving at a possible mass-casualty collision, what is your first priority?
   Assess the scene and ensure it is safe — injured responders help no one and add to the patient count.

2. A steady flow of dark red blood from an arm gash is what kind of bleeding, and how is it controlled?
   Venous bleeding; direct pressure is usually sufficient.

3. The wound is hidden by a sleeve — what do you do?
   Cut the clothing away until the entire wound is visible. You cannot treat what you cannot see.

4. Which triage colour sends a patient to the highest-level trauma centre?
   Red — dangerous injury patterns or abnormal mental status/vital signs. Yellow (mechanism or judgment) goes to a trauma centre.

5. Which triage error is dangerous?
   Under-triage: a critical patient at a non-trauma centre loses quality of care. Over-triage only costs efficiency.

6. When is immediate transport with resuscitation en route considered in traumatic arrest?
   Arrest witnessed by EMS or occurring within about 15 minutes of arrival.

Chapter 3 recall

1. Why use the trauma jaw thrust first in an unconscious patient with gurgling respirations?
   It opens the airway with little or no cervical-spine movement — and manual maneuvers have no contraindications in trauma.

2. The patient becomes apneic with suspected cervical injury — which device?
   A supraglottic airway: its signature advantage is insertion independent of patient position.

3. Why is airway obstruction harder to manage in a child?
   The larger occiput and tongue create greater obstruction potential; positioning (torso padding, not head padding) is everything.

4. Why consider early bag-mask support in an older adult?
   Greatly limited physiologic reserve.

5. Dentures in, or out?
   Intact dentures stay in (better mask seal); dislodged or broken dentures come out.

Chapter 4 recall

1. The monitors disagree with the patient — whom do you believe?
   The patient. Treat the clinical condition, not the monitor.

2. What must happen before any field intubation?
   Preoxygenation with high-concentration oxygen.

3. What end-tidal carbon-dioxide level do you maintain when ventilating?
   35–40 mm Hg (the manual’s normal reading is 30–40).

4. What is capnography for during reassessment?
   Confirming and continuously monitoring tube placement — it does not measure blood pressure or arterial oxygen.

5. The three findings of tension pneumothorax?
   Worsening distress or difficult bagging + unilateral reduced sounds + decompensated shock (systolic under 90 with narrowed pulse pressure).

Chapter 5 recall

1. Multiple left-chest stab wounds; bleeding controlled; now combative, pale, “can’t breathe” — next step?
   Decompress the left chest. After X come A and B; tension pneumothorax is the fastest reversible cause of this shock.

2. Partner wants to release wound pressure to start an IV — response?
   No. Keep the pressure on and begin transport; releasing controlled hemorrhage to gain access would be disastrous.

3. Confused, no radial pulse, IV in place — how much fluid?
   Titrate until the radial pulse returns (systolic ~80–90); a blind litre could pop the clot.

4. Radial pulse returns after 400 mL — now what?
   Stop fluids and give 2 g TXA; perfusion targets are met, and morphine in shock risks dangerous hypotension.

5. The patient takes clopidogrel — does it matter?
   Yes: his platelets are disabled for days; he will need platelets and the receiving team must know now.

6. Which class of hemorrhage narrows the pulse pressure while systolic stays normal?
   Class II (15–30% loss) — the classic compensated trap.

Chapter 6 recall

1. Older patient on warfarin, fall days ago, worsening confusion and headache — suspect what?
   Subdural hematoma.

2. Eye opening to speech, confused speech, withdraws normally on motor testing — GCS?
   4 + 4 + 4 = 12 → moderate TBI (13–15 mild, 9–12 moderate, 3–8 severe).

3. Right pupil blown, left motor delay — what is happening?
   Uncal herniation compressing cranial nerve III, the motor tract, and the reticular activating system.

4. Most concerning new finding: SBP 88, SpO2 93%, motor score 4, or hemiplegia?
   Systolic 88 — pressure below 90 drives secondary brain injury.

5. What characterizes the compensated Monro–Kellie state?
   CSF and venous blood volume fall while vital signs remain normal — the calm before the ICP spike.

Chapter 7 recall

1. Ambulatory cyclist, split helmet, clavicle pain — first action?
   Manual in-line stabilization: significant helmet damage is itself a spinal red flag.

2. GCS 15 but severe clavicle pain — does she need motion restriction?
   Yes: a distracting injury plus the mechanism supports collar and restriction despite the normal GCS.

3. Which body part is secured to the board first?
   Torso — then head, then legs/pelvis.

4. Where does the padding go on an adult?
   Behind the head (prevents hyperextension). A child is padded under the shoulders/torso instead (prevents hyperflexion).

5. Supine position worsens her breathing — what do you do?
   Raise the back of the stretcher slightly: alignment is essentially maintained and ventilation is relieved.

6. Warm skin, slow-normal pulse, low pressure after cord injury — which shock?
   Neurogenic (lost sympathetic tone). Target MAP 85–90; atropine for bradycardia with significant hypotension.

Chapter 8 recall

1. A toddler’s hand is red and wet-looking with blisters after hot water — what depth?
   Partial thickness — the most painful burn; scalds are the most common burns at ages 1–5.

2. The babysitter is applying ice — next step?
   Stop the burning process and remove the ice: ice trades brief pain relief for extra tissue death in the zone of stasis.

3. How do you manage the blisters?
   Leave them intact; cover with a dry, loose, sterile dressing.

4. The burn ends in a sharp line above the wrist with no splash marks — what must you consider?
   Nonaccidental injury — a glove-pattern immersion burn.

5. Which fluid for the Parkland estimate, and what steers the rate?
   Lactated Ringer; urine output is the primary endpoint — avoid boluses unless hypotensive.

Chapter 9 recall

1. Severe isolated femur-fracture pain, 20-minute transport — best analgesic?
   Fentanyl: fastest onset, short duration, least hemodynamic effect.

2. Hypovolemic shock with no visible source — what does it mean?
   Intra-abdominal bleeding until proven otherwise.

3. BP 70/50 with suspected abdominal bleed and no TBI — how do you run fluids?
   Titrate carefully to systolic 80–90 (MAP ~60–65); restoring normal pressure could pop the clot.

4. Which bleeds more — a partial or complete amputation?
   Partial: fully transected arteries retract and constrict; partially cut ones cannot.

5. What kills crush-injury patients at release?
   Reperfusion hyperkalemia and acidosis — fluid-load with normal saline before extrication and watch for peaked T waves.

6. A hard, tender uterus after a minor collision?
   Abruptio placentae — and vaginal bleeding is visible in only 70% of cases.

Source coverage map

Traceability from the source text (150 numbered sections) to this guide, so omissions are deliberate and visible, never silent.