Head injuries: emergency assessment, skull fractures, and concussion protocols¶

Blunt head trauma occurs during motor vehicle collisions, falls from heights, sports impacts, bicycle crashes, and industrial accidents. While many head bumps result only in localized scalp contusions, high-energy kinetic impacts can produce life-threatening intracranial hemorrhage, cerebral contusions, traumatic brain injuries (TBI), and cervical spine fractures.

The human skull is a rigid, non-expanding vault containing the brain, cerebrospinal fluid, and arterial blood. Bleeding inside the cranium creates elevated intracranial pressure (ICP), rapidly compressing brain tissue, restricting cerebral blood flow, and precipitating brainstem herniation and fatal respiratory arrest. A patient who appears completely alert immediately following a blow can deteriorate into an irreversible coma within hours.

This guide provides technical first aid triage, clinical neurological indicators, cervical spine stabilization protocols, and return-to-play frameworks based on clinical standards from the American College of Surgeons (ATLS), the Canadian C-Spine Rule, the Pediatric Emergency Care Applied Research Network (PECARN), and the Concussion in Sport Group (CISG).

Do this now: immediate head injury and spinal stabilization¶

If an adult or child has suffered a significant impact to the head:

1. Maintain manual in-line cervical spine stabilization. Assume a cervical spine (neck) fracture exists until proven otherwise by medical imaging. Kneel at the top of the patient's head, place your hands firmly along both sides of their skull, and hold the head completely still in the neutral position found. Do not allow the patient to turn their head, sit up, or nod.
2. Check the level of consciousness immediately. Assess responsiveness using the AVPU framework: is the person Alert, responsive to Voice, responsive to Pain, or Unresponsive? Any period of unconsciousness, even lasting just two seconds, mandates emergency medical evaluation.
3. Call emergency dispatch if red-flag signs are present. Dial your local emergency number (911 in the United States and Canada, 112 across the European Union, 999 in the United Kingdom) immediately if the patient lost consciousness, experienced a seizure, vomited repeatedly, exhibits unequal pupils, or sustained high-speed impact.
4. Control scalp hemorrhage with circumferential surface pressure. Scalp lacerations bleed profusely due to dense subdermal vascular networks. Press a sterile gauze compress firmly against the wound. However, if you feel a depression, spongy bone, or visible skull fracture, do not apply direct downward pressure onto the bone; place a doughnut-ring dressing around the perimeter to arrest bleeding without driving bone fragments into the brain.
5. Manage the airway using only the modified jaw-thrust. If the patient is unconscious and vomiting or snoring, do not tilt the head backward (head-tilt chin-lift). Place your index and middle fingers behind the angles of the lower jawbone and lift the jaw forward and upward to open the airway without moving the cervical vertebrae.

Head injury and spinal stabilization response flowchart¶

                   BLUNT HEAD TRAUMA INCIDENT
                               │
               Did the patient lose consciousness, suffer
               high-speed impact, or report severe neck pain?
                               │
               ┌───────────────┴───────────────┐
              YES                             NO
               │                               │
      ┌────────┴────────┐             ┌────────┴────────┐
      │ CRITICAL TBI    │             │ CONCUSSION &    │
      │ EMERGENCY       │             │ MONITORING      │
      └────────┬────────┘             └────────┬────────┘
               │                               │
   1. Hold head still (C-spine)    1. Screen for concussion signs
   2. Open airway with JAW-THRUST  2. Rest in quiet environment
   3. Check pupils for asymmetry   3. Apply cold pack to bump
   4. Call 911 / 112 / 999         4. Adult observation 24 hours
   5. NEVER let patient sit up     5. Zero return to sports/play
               │                               │
               └───────────────┬───────────────┘
                               │
                 RED-FLAG INTRACRANIAL PRESSURE (ICP)
                               │
            Are any of the following signs present?
            - Battle's sign (mastoid bruising behind ears)
            - Raccoon eyes (bilateral orbital bruising)
            - Clear fluid draining from nose or ears (CSF)
            - Blown pupil (one dilated, non-reactive pupil)
            - Repeated projectile vomiting or seizures
                               │
               ┌───────────────┴───────────────┐
              YES                             NO
               │                               │
      ┌────────┴────────┐             ┌────────┴────────┐
      │ ACUTE EMERGENCY │             │ CLINICAL CLINIC │
      │ SURGICAL TRIAGE │             │ EVALUATION      │
      └─────────────────┘             └─────────────────┘
   1. Immediate trauma center transport1. Physician evaluation today
   2. Continuous airway monitoring 2. Monitor for delayed decline
   3. Prepare for log-roll if emesis3. Follow return-to-learn plan

Pathophysiology of traumatic brain injury (TBI)¶

Understanding the internal mechanical trauma of the brain explains why external injuries do not predict internal brain damage:

       BIOMECHANICS AND PATHOPHYSIOLOGY OF TBI
┌─────────────────────────────────────────────────────────────┐
│ 1. COUP-CONTRECOUP MECHANISM                                │
│    - Coup: Brain strikes the inside of the skull at the     │
│      point of impact, bruising frontal or temporal lobes.   │
│    - Contrecoup: Brain rebounds violently across skull,     │
│      striking the opposite interior wall, causing severe    │
│      secondary tissue tearing and microvascular bleeding.   │
├─────────────────────────────────────────────────────────────┤
│ 2. THE MONRO-KELLIE HYPOTHESIS & ICP                        │
│    - The adult skull is rigid and fixed in volume.          │
│    - Contents: Brain tissue (80%), Blood (10%), CSF (10%).  │
│    - Any expanding volume (hematoma or cerebral edema)      │
│      rapidly drives Intracranial Pressure (ICP) upward,     │
│      choking off arterial blood supply to neurons.          │
├─────────────────────────────────────────────────────────────┤
│ 3. INTRACRANIAL HEMATOMAS                                   │
│    - Epidural: Middle meningeal artery tear; rapid arterial │
│      bleeding; classic "lucid interval" before collapse.    │
│    - Subdural: Tearing of bridging veins; venous bleeding;  │
│      slower onset over hours or days, common in seniors.    │
│    - Subarachnoid: Bleeding into CSF spaces; "thunderclap"  │
│      worst headache of life; rapid meningeal irritation.    │
└─────────────────────────────────────────────────────────────┘

The lethal "lucid interval" of epidural hematomas¶

An epidural hematoma typically results from a blow to the side of the head (the temple or pterion), fracturing the thin squamous temporal bone and lacerating the underlying middle meningeal artery. - The classic clinical trap: The patient is knocked unconscious briefly, wakes up, appears completely coherent and conversant, and insists they are fine. - The rapid collapse: Because the bleeding is arterial under high pressure, a hematoma rapidly expands between the skull and the dura mater. Within 30 to 120 minutes, the expanding clot suddenly exhausts compensatory mechanisms, intracranial pressure spikes, the patient loses consciousness, develops a blown pupil, and suffers fatal brainstem herniation. - The rule: Anyone who loses consciousness, even momentarily, following a head injury must be evaluated at an emergency department with a non-contrast CT scan, regardless of how well they appear afterward.

Red-flag clinical indicators of basilar skull fractures¶

Basilar skull fractures occur at the anatomical floor of the cranial vault (cribriform plate, orbital roof, sphenoid, or petrous temporal bones). They present with distinct physical findings that signal severe underlying brain trauma:

       PHYSICAL INDICATORS OF BASILAR SKULL FRACTURES
┌──────────────────────┬──────────────────────┬──────────────────────┐
│ Clinical Sign        │ Physical Presentation│ Anatomical Indication │
├──────────────────────┼──────────────────────┼──────────────────────┤
│ Battle's Sign        │ Purplish ecchymosis  │ Petrous temporal bone│
│                      │ (bruising) over the  │ fracture; middle     │
│                      │ mastoid behind ears  │ cranial fossa bleed  │
├──────────────────────┼──────────────────────┼──────────────────────┤
│ Raccoon Eyes         │ Dark bilateral       │ Anterior cranial     │
│ (Periorbital         │ bruising around both │ fossa fracture; roof │
│ Ecchymosis)          │ eye sockets          │ of orbit basilar tear│
├──────────────────────┼──────────────────────┼──────────────────────┤
│ Cerebrospinal Fluid  │ Clear, watery fluid  │ Dural tear; cribriform│
│ Rhinorrhea/Otorrhea  │ draining from nose   │ plate or temporal    │
│                      │ or ear canal         │ fracture             │
├──────────────────────┼──────────────────────┼──────────────────────┤
│ Hemotympanum         │ Purple or blue blood │ Petrous fracture with│
│                      │ visible behind the   │ bleeding into the    │
│                      │ ear tympanic membrane│ middle ear space     │
├──────────────────────┼──────────────────────┼──────────────────────┤
│ Blown Pupil          │ One pupil widely     │ Uncal herniation     │
│ (Anisocoria)         │ dilated and fixed;   │ compressing third    │
│                      │ does not react to light cranial nerve       │
└──────────────────────┴──────────────────────┴──────────────────────┘

The halo test for cerebrospinal fluid (CSF)¶

When bloody fluid drains from the nose or ears of a head injury victim, first aiders must determine whether cerebrospinal fluid is present: - How to test: Drip a drop of the bloody fluid onto a sterile white paper towel, coffee filter, or gauze pad. - The result: Blood cells contain heavy iron and remain in a dark, red circle in the center. Cerebrospinal fluid is thin and watery, wicking outward much faster, creating a clear or light-yellow concentric ring (halo) surrounding the central blood spot. - Operational directive: Never pack cotton balls or gauze into the nose or ear canal to stop CSF drainage. Packing the canal blocks fluid flow, forcing bacteria backward into the subarachnoid space and causing fatal bacterial meningitis. Allow fluid to drain freely onto a loose, sterile dressing.

Cushing's triad (the terminal sign of brain herniation)¶

Cushing's Triad represents an ominous physiological reflex indicating extreme intracranial pressure and imminent fatal brainstem herniation: 1. Severe hypertension with widening pulse pressure: Systolic blood pressure spikes (such as 210 mmHg) while diastolic pressure remains normal or drops (such as 60 mmHg). 2. Profound bradycardia: The heart rate slows dramatically, dropping to 35 to 50 beats per minute. 3. Irregular respirations: Chaotic, irregular, or gasping breathing patterns (Cheyne-Stokes breathing or ataxic breathing).

Cervical spine stabilization and airway management¶

Every patient with significant head trauma must be treated as having a coexisting cervical spine fracture until cleared by medical professionals. Up to 10 percent of severe traumatic brain injury victims have a concurrent spinal column fracture.

       CERVICAL SPINE RESCUE BIOMECHANICS
┌─────────────────────────────────────────────────────────────┐
│ 1. MANUAL IN-LINE STABILIZATION (MILS)                      │
│    - Rescuer positions themselves directly above patient's  │
│      crown, resting elbows on the ground for stability.     │
│    - Place wide palms on both sides of skull; fingers cup   │
│      the jaw angles. Maintain head in dead neutral.         │
├─────────────────────────────────────────────────────────────┤
│ 2. MODIFIED JAW-THRUST (AIRWAY WITHOUT TILT)                │
│    - Do NOT tilt head or extend neck.                       │
│    - Place index and middle fingers behind mandibular angles│
│      and lift mandible upward toward the ceiling.           │
│    - Displaces tongue off posterior pharynx without moving  │
│      any cervical vertebrae.                                │
├─────────────────────────────────────────────────────────────┤
│ 3. THE HIGH-RISK VOMITING PROTOCOL                          │
│    - Head injuries routinely induce projectile vomiting.    │
│    - If patient vomits, they will asphyxiate if supine.     │
│    - Rescuer 1 maintains head stability while Rescuer 2 and │
│      3 log-roll the torso as a single unified axis onto the  │
│      side (HAINES recovery position) to clear vomit.        │
└─────────────────────────────────────────────────────────────┘

Pediatric head trauma and the PECARN criteria¶

Children under two years of age possess unique cranial anatomical vulnerabilities: their skull bones are thin and pliable, cranial sutures and fontanelles are open, their brain tissue is more unmyelinated, and their heads are disproportionately large and heavy relative to their body mass.

       PEDIATRIC EMERGENCY CARE APPLIED RESEARCH NETWORK
┌──────────────────────┬──────────────────────┬──────────────────────┐
│ Age Category         │ High-Risk Criteria   │ Emergency Action     │
│                      │ (Clinically Signif.) │                      │
├──────────────────────┼──────────────────────┼──────────────────────┤
│ Children Under       │ - Glasgow Coma < 15  │ Immediate non-       │
│ 2 Years              │ - Palpable skull     │ contrast cranial CT  │
│                      │   fracture           │ scan; pediatric      │
│                      │ - Altered mental     │ trauma activation    │
│                      │   status / lethargy  │                      │
│                      │ - Non-frontal scalp  │                      │
│                      │   hematoma (parietal)│                      │
│                      │ - Fall > 1 meter (3ft│                      │
├──────────────────────┼──────────────────────┼──────────────────────┤
│ Children 2 Years     │ - Glasgow Coma < 15  │ Urgent physician     │
│ and Older            │ - Signs of basilar   │ evaluation; CT scan  │
│                      │   fracture           │ for persistent signs │
│                      │ - History of loss of │                      │
│                      │   consciousness      │                      │
│                      │ - Repeated vomiting  │                      │
│                      │ - Severe headache    │                      │
│                      │ - Fall > 1.5 m (5ft) │                      │
└──────────────────────┴──────────────────────┴──────────────────────┘

Non-frontal hematomas in infants: A soft, boggy swelling or "goose egg" on the forehead of a toddler is common and typically benign. However, a large swelling located on the side (temporal) or back (parietal or occipital) of an infant's skull carries a high correlation with underlying skull fractures and intracranial hemorrhage. Any infant with a non-frontal hematoma requires immediate pediatric hospital evaluation.

Concussion mechanics and Second Impact Syndrome¶

A concussion is a functional traumatic brain injury induced by biomechanical forces. It results from linear deceleration or rotational shear stress that stretches and damages axonal membranes, causing a profound metabolic mismatch: neurons demand massive glucose energy to restore ionic balance, while localized cerebral blood flow is simultaneously reduced.

Common concussion symptom clusters¶

• Physical: Throbbing headache, dizziness, nausea, light sensitivity (photophobia), sound sensitivity (phonophobia), balance instability.
• Cognitive: Brain fog, feeling slowed down, difficulty concentrating, retrograde amnesia (forgetting events before the hit) or anterograde amnesia (inability to form new memories).
• Emotional: Uncharacteristic irritability, heightened sadness, emotional lability, anxiety.
• Sleep: Drowsiness, sleeping significantly more or less than usual, difficulty falling asleep.

Second Impact Syndrome (SIS): the fatal danger¶

Second Impact Syndrome occurs when an athlete or individual sustains a second concussive blow before the brain has completely recovered from an initial concussion (often days or weeks earlier). - The lethal mechanism: The unhealed brain's autoregulatory vascular system fails completely. Within two to five minutes of the second minor impact, massive, uncontrollable cerebral vascular engorgement occurs, causing catastrophic intracranial hypertension and brainstem herniation. - Mortality rate: Second Impact Syndrome carries a mortality rate approaching 50 percent, and permanent neurological disability in nearly 100 percent of survivors. - The iron rule: "When in doubt, sit them out." Any athlete, child, or adult exhibiting any concussion symptom must be removed from play immediately and barred from returning to sports until cleared in writing by a licensed physician.

Graduated Return-to-Play protocol (Berlin/Amsterdam consensus)¶

Recovery from a concussion must follow a disciplined, stepwise protocol. A patient must spend at least 24 hours at each stage without symptom recurrence before advancing:

Master head injury emergency checklist¶

• Stabilize the head and neck in neutral alignment immediately upon arrival.
• Assess consciousness using the AVPU framework.
• Call 911 / 112 / 999 if there was any loss of consciousness, seizure, or vomiting.
• Use the modified jaw-thrust to maintain airway without tilting the cervical spine.
• Inspect the skull for Battle's sign, raccoon eyes, or clear CSF drainage.
• Do not apply direct downward pressure onto depressed or spongy skull bone.
• Log-roll the patient as a single unified axis if vomiting occurs.
• Never allow an injured athlete showing concussion signs to return to play.
• Monitor pediatric patients for non-frontal scalp hematomas and extreme lethargy.
• Keep an adult observer with minor concussion patients for a full 24 hours.

Frequently asked questions¶

Is it dangerous to let someone go to sleep after hitting their head?¶

It is completely safe to let a person sleep after a minor head bump, provided they have been evaluated and do not display any red-flag emergency symptoms (no loss of consciousness, no repeated vomiting, normal pupil responses, normal balance, and clear speech). Sleep promotes neurological healing. However, during the first 12 to 24 hours, a responsible adult should observe them periodically to ensure they are breathing normally and can be easily roused to normal alertness. If the person cannot be awakened or is deeply confused when roused, dial emergency services immediately.

What is the difference between a concussion and a brain contusion?¶

A concussion is primarily a functional disturbance of brain metabolism and neuronal signaling without visible structural damage on standard CT or MRI scans. A brain contusion is a physical, structural bruise of brain tissue, characterized by localized capillary rupture, micro-hemorrhages, and localized cerebral edema, clearly visible on a CT scan. Contusions frequently occur in coup-contrecoup injuries when the brain strikes the bony ridges of the skull.

Why do scalp cuts bleed so much more than cuts elsewhere on the body?¶

The human scalp is one of the most vascularized structures in the human anatomy. The blood vessels supplying the scalp are embedded within the dense, fibrous galea aponeurotica connective tissue layer. When the scalp is torn or lacerated, these dense fibrous bands physically hold the severed arterial walls open, preventing the blood vessels from naturally retracting and constricting to form clots. Consequently, even a small 2-centimeter scalp laceration can produce dramatic, heavy bleeding.

What should I do if clear watery fluid is draining from the nose or ear after a blow?¶

Clear, watery drainage following a significant blow to the head indicates a basilar skull fracture with a tear in the protective meningeal dura mater, allowing cerebrospinal fluid (CSF) to leak into the nasal cavity or ear canal. Do not attempt to plug, pack, or bandage the nose or ear canal with cotton, tissues, or gauze. Blocking the exit forces the fluid backward into the intracranial vault, dramatically increasing the risk of lethal bacterial meningitis. Cover the area loosely with a sterile gauze pad to absorb runoff and call emergency medical services immediately.

What is Second Impact Syndrome and why is it fatal?¶

Second Impact Syndrome (SIS) occurs when a person sustains a second concussion or head impact before the symptoms of an earlier concussion have fully resolved. The second impact can be remarkably minor, even a slight jolt to the chest that snaps the head. Because the brain's cerebral autoregulation is still compromised from the first injury, the second blow triggers sudden, massive, irreversible cerebral vascular engorgement. The brain swells catastrophically within two to five minutes, causing massive intracranial pressure, brainstem herniation, and death in roughly half of all cases.

Related guides¶

• Broken bones, fractures, and sprains
• Severe bleeding control and tourniquets
• Seizure first aid and safety protocols
• Car crash emergency scene management
• Emergency numbers and international dispatch