nuero lect 2 pt 2 closed head injuries TBI and fx

Glasgow Coma Scale (GCS) and Airway Management

• The GCS is a tool for initial assessment, monitoring, and guiding treatment for neurological impairments.

• Airway Cutoff: If the GCS score is less than $9$, the patient requires intubation (score of $8$ or less).

Eye Response ($1$ to $4$ Scale)

• $4$: Spontaneous opening.

• $3$: Opens to verbal stimuli (name calling).

• $2$: Opens to painful stimuli (e.g., sternal rub).

• $1$: No response.

Verbal Response ($1$ to $5$ Scale)

• $5$: Fully awake, alert, and oriented.

• $4$: Confused/disoriented; inappropriate words or slow response.

• $3$: Inappropriate words; speaking without sense but not a word salad.

• $2$: Incomprehensible sounds; no actual words formed.

• $1$: No response.

Motor Response ($1$ to $6$ Scale)

• $6$: Follows commands, moves extremities.

• $5$: Localizes pain (moves toward/tries to remove painful stimuli).

• $4$: Withdraws from pain (moving away from source).

• $3$: Decorticate posturing (flexion toward the core); indicates severe injury.

• $2$: Decerebrate posturing (extension and rotation); worse prognosis than decorticate.

• $1$: No response; often indicates brain death.

Traumatic Brain Injury (TBI) Overview

Definitions and Severity

• TBI: A nondegenerative, non-congenital insult to the brain from external mechanical force.

• Severity Classification (within $48$ hours):   - Severe: GCS $3$ to $8$.   - Moderate: GCS $9$ to $12$.   - Mild: GCS $13$ to $15$.

Epidemiology and Causes

• Leading cause overall: Motor vehicle accidents (MVAs).

• Leading cause for individuals > 75: Falls.

• Third leading cause: Firearms.

• Risk is highest for ages $15$ to $24$; men are twice as likely as women to sustain a TBI.

• TBI accounts for approximately $40.0\%$ of deaths from acute injuries in the US.

Pathophysiology of Brain Injury

Primary vs. Secondary Injury

• Primary Injury: Occurs at the moment of trauma (e.g., direct impact, skull fractures, intracranial hematoma, contusions, penetrating wounds).

• Diffuse Axonal Injury (DAI): A type of primary injury caused by rapid acceleration/deceleration (whiplash). Stretches or tears axons ("wires"), disrupting communication. It is difficult to treat and reverse.

• Secondary Injury: A cascade of mechanisms following the initial insult (e.g., edema, swelling, increased intracranial pressure, hydrocephalus, brain herniation, electrolyte imbalances).

Management and Diagnosis

• Imaging: Non-contrast CT head is the preferred modality in the acute phase to recognize gross abnormalities.

• Acute Interventions:   - Airway protection (intubation if GCS < 9).   - Hemodynamic and vital sign monitoring (BP, oxygenation).   - Raise head of bed to promote venous drainage and decrease intracranial pressure (ICP).   - Mannitol: Osmotic diuretic used to decrease cerebral edema.   - Hyperventilation: Induces respiratory alkalosis to decrease brain swelling.   - Aggressive Fluid Resuscitation: Use normal saline ($0.9\%$ NS) to maintain sodium levels.   - Anti-Seizure Medication: Prevents and treats post-traumatic seizures, common in frontal and temporal lobe injuries.   - Neurosurgical consultation for potential surgical intervention.

Concussion and Post-Concussive Syndrome

• Mild TBI (Concussion): Mental status alteration with or without loss of consciousness. Symptoms include amnesia (retrograde or anterograde), nausea, and vomiting.

• Management: Cognitive and physical rest, with observation for at least $24$ hours.

• Return to Activity: Patients should gradually resume activity. If symptoms return, they must wait $24$ hours before trying the next level of exertion again.

• Post-Concussive Syndrome: Symptoms continuing for $7$ to $10$ days or longer after a mild TBI.

Skull Fractures

• Basilar Skull Fracture: Most common serious type, involving bones at the base of the skull.   - Sign: Teapot sign/Double Ring sign (halo) on a sheet indicates a CSF leak.   - Pneumocephalus: Air inside the brain; treated conservatively with oxygen and supine positioning.

• Open vs. Closed: Open fractures (brain/scalp exposed) require antibiotics (e.g., Vancomycin) to prevent meningitis.

• Linear Skull Fracture: A hairline crack; usually managed conservatively unless the scalp is open.

• Diastatic Skull Fracture: Follows suture lines; occurs in newborns and infants before fontanels are closed.

• Depressed Skull Fracture: Bone is pressed down on the brain; often requires surgery for evacuation of bleeds and reconstruction with plates/mesh.

Questions & Discussion

• Q: How do you give painful stimuli?

• A: Sternal rub is one method, or engaging the extremities in the hospital setting.

• Q: Why is decerebrate posturing worse than decorticate?

• A: Decorticate shows the body is still trying to hold extremities toward the core; decerebrate (extension) indicates a deeper, more severe level of injury.

• Q: Why use fluid resuscitation if there is edema?

• A: You must keep the patient hydrated while diuresing. Using hypertonic fluids or $0.9\%$ Normal Saline (NS) introduces sodium, causing water to follow and reducing swelling through osmotic pressure.

• Q: Do you always do a CT with contrast for head injuries?

• A: No, you always use non-contrast CT because a bleed will appear high-intensity (bright), and contrast might mask it.