Head, Facial, and Neck Trauma Flashcards
The populations most at risk for serious head injury are ___ between the years of ___ and ___, ___ and ___ ___, and the ___.
males ; 15 ; 24 ; infants ; young children ; elderly
What is the most frequent cause of trauma death?
Severe head injury
Mechanisms of injury: The structures of the ___, ___, and ___ protect very well against most blunt trauma.
head ; face ; neck
Mechanisms of injury: Why are significant facial injuries less likely to occur?
- Head’s frontal or parietal regions are more likely to impact (in things like auto crashes)
- Conscious victims try to protect facial area from injury and head/chest/arms absorb energy
Mechanisms of injury: How is the neck protected from blunt trauma?
Head and chest protrude more anteriorly; laterally protected as shoulders protrude a significant distance from the neck
Mechanisms of injury: Penetrating injuries to the head, face, and neck usually result from either ___ or ___.
gunshots ; stabbings
Mechanisms of injury: ___ wounds to the head and face tend to be superficial because of the region’s extensive ___ components.
Knife ; skeletal
Mechanisms of injury: What are some examples of penetrating injuries that involve the head, face, and neck?
- “Clothesline” impact with a wire fence while a victim is riding an all-terrain vehicle
- Bites from humans, dogs, or animals
- Tongue bitten when victim traps between teether during an impact
How is head injury defined?
Traumatic insult to the cranial region that may result in injury to soft tissues, bony structures, and the brain.
Head injury: Most superficial head injuries involve the ___. Its blood vessels lack the ability to constrict a effectively as those elsewhere, so the wound tends to bleed ___.
scalp ; heavily
Head injury: What are some concerns with scalp wounds?
- Serious blood loss from scalp wounds can contribute to shock - and could cause hypovolemia - if left untreated
- Provide a route for infection because emissary veins drain from dural sinuses, through the cranium, ad into the superficial venous circulation
Head injury: What is a common and special type of scalp wound? Describe what happens.
Avulsion - areolar tissues is only loosely attached to the skull, an glancing blows can create a shearing force against the scalp’s border; frequently tears a flap of scalp loose and folds it back against the uninjured scalp exposing portion of cranium
Head injury: What are the four ways cranial fractures present?
Linear, depressed, comminuted, or basilar
Head injury: ___ fractures are small cracks in the cranium and represent about 80% of all skull fractures.
Linear
Head injury: What is the thinnest and most frequently fracture cranial bone?
Temporal bone
Head injury: What is a depressed cranial fracture?
Inward displacement of the skull’s surface with greater likelihood of intracranial damage
Head injury: What is a comminuted cranial fracture?
Multiple skull fragments that may penetrate the meninges and cause physical harm to the structures beneath
Head injury: What are the scalp/head injury presentations?
- Hematoma: blow disrupts blood vessels, resulting in accumulating blood and a hematoma
- Depression: blow may tear fascial layers und the scalp and result in a depression, with or without a depressed skull fracture
- Normal scalp contour: blood may fill the space vacated by the torn fascial layers OR blood may fill the area vacated by a depressed skull fracture
Head injury: A common type of skull fracture involves the ___ of the skull because it is permeated with foramina (openings) for the ___ ___, ___ ___, and various ___ ___.
base ; spinal cord ; cranial nerves ; blood vessels
Head injury: What are the hollow or open structures on the basilar skull that weaken it and leave the basilar area prone to fracture?
Sinuses, orbits of the eye, nasal cavities, external auditory canals, and middle/inner ears
Head injury: What are signs of basilar skull fractures?
Varies by location:
- If fracture involves auditory canal/lower later areas of skull: hemorrhage may migrate to the mastoid region (just posterior and slightly inferior to the ear)
- —Causes characteristic discoloration called retroauricular ecchymosis or “Battle’s sign”
-Bilateral periorbital ecchymosis sometimes referred to as “raccoon eyes”, which is dramatic discoloration around the eyes associated with orbital fractures and hemorrhage into surrounding tissue
Head injury: Basilar skull fracture can tear the ___ ___, opening a wound between the brain and body’s exterior. This may permit cerebrospinal fluid to seep out through a nasal cavity or external auditory canal.
dura mater
Head injury: The “halo” sign (dark red circle surrounded by a lighter, yellowish one indicating blood mixed with cerebrospinal fluid) is most reliable when associated with fluid leaking from the ___.
ear
Head injury: The ___ level of CSF (cerebrospinal fluid) is normally half that of the blood. If you are unsure whether a clear fluid is water or CSF, check the ___ level of the fluid and compare it to the patient’s blood ___ level.
glucose (all blanks)
Head injury: How many wounds are produced with a bullet to the cranium?
2 - entrance wound often producing a comminuted fracture sending bone fragments in to the brain; exit wound blown outward and more severe in appearance
Head injury: What effect does the energy of the projectile’s passage have on the cranium?
- Can cause cavitational wave of extreme pressure, which is contained and enhanced by the rigid container of the skull, resulting in extreme damage to the cranial contents
- —If kinetic energy strong enough: skull may fracture and “explode” outward
Head injury: What type of injury does a bullet entering at an angle potentially cause? Why?
Deflected within cranium and continues to move along craniums interior until energy is exhausted - devastating damage to the cerebral cortex and rarely survivable
Head injury: T or F. You should remove an impaled object causing cranial injury.
False - removal may cause further injury and increase blood accumulation
*Steve Irwin flashback :( *
Head injury: A ___ fracture by itself is a skeletal injury that will heal with time; however, the forces necessary to fracture the ___ are often sufficient to induce ___ injury.
cranial ; skull ; brain
Brain injury: What is the definition of brain injury?
A traumatic insult to the brain capable of producing physical, intellectual, emotional, social, and vocational changes; classified as direct or indirect injury to the tissue of the cerebrum, cerebellum, or brainsteml
Brain injury: What are some potential damages resulting from direct (or primary) brain injury?
- Mechanical injury to nervous system cells and impair their function
- Disrupt blood vessels - both restricting blood flow through the injured area and causing irritation of nervous tissue as blood flows into it
- Disrupt blood-brain barrier
- Serious jarring may damage capillary walls, affect their permeability, and cause fluid shift to the interstitial space, or tissue edema
Brain injury: What are the two specific types of direct brain injury?
Coup
Contrecoup
Brain injury: What are coup injuries?
Injury to the brain occurring on the same side as the impact
Brain injury: What are contrecoup injuries?
An injury to the brain opposite the site of impact
Brain injury: What are the two categories of direct brain injuries?
Focal or diffuse
Brain injury: Focal injuries occur at a ___ loction in the brain and include ___ and ___ ___.
specific ; contusion ; intracranial hemorrhages
Brain injury: Define and describe cerebral contusions.
- Caused by blunt trauma to local brain tissue that produces capillary bleeding into the substance of the brain
- Often produces prolonged confusion or other types or neurologic deficit
- May result from a coup or contrecoup mechanism
- May occur at one or several sites in the brain
Brain injury: What is the most commonly injured lobe?
Frontal
Brain injury: What is intracranial hemorrhage?
Bleeding directly into the tissue of the brain
Brain injury: What are the three types of bleeding brain injuries (ordered from most superficial to the deepest)?
- Epidural hematoma
- Subdural hematoma
- Intracerebral hemorrhage
Brain injury: What is epidural hematoma?
Accumulation of blood between the dura mater and the cranium; usually involves arterial vessels (often the middle meningeal artery in the temporal region); intracranial pressure builds rapidly - patient moves quickly towards unresponsiveness as pressure builds
Brain injury: What is subdural hematoma?
- Collection of blood directly beneath the dura mater and within the subarachnoid space;
- occurs very slowly;
- subtle presentation because usually due to rupture of small venous vessel (often one of those bridging to dural sinuses);
- free blood in CSF may clog structures responsible for fluid’s reabsorption and result in increasing intracranial pressure
Brain injury: Suspect ___ ___ in medical (nontrauma) patient who demonstrates neurologic signs and symptoms.
subdural hematoma
Brain injury: The ___ process and chronic ___ reduce the size of the brain, thus causing greater and less controlled motion of the brain; increases likelihood of injury (specifically subdural hematoma)
aging ; alcoholic
Brain injury: What can happen with intracerebral hemorrhage brain injuries?
Tissue edema resulting from free blood irritating the nervous tissue
Brain injury: List and describe two other local insults to the brain that result in increasing intracranial pressure.
- Cerebral edema: inflammation response initiated when cerebral tissue injured which permits fluid and proteins to pass through cerebral capillary walls; exert an osmotic pressure and draw water into and expand the interstitial space
- Hydrocephalus: hemorrhage into the subarachnoid space which then clogs the arachnoid villi (small structures that permit fluids in CSF to re-enter blood stream); accounts for accumulation of CSF and increase in ICP
Brain injury: What do diffuse injuries involve and include?
- Involve more general scenario of injury
- Include mild (concussions), moderate, and severe axonal disruptions
Brain injury: What is diffuse axonal injury (DAI)?
Type of brain injury characterized by shearing, stretching, or tearing of nerve fibers with subsequent axonal damage
Brain injury: What are axons?
Long communication pathways of the nerve cells
Brain injury: A ___ is a mild to moderate form of DAI and most common outcome of blunt trauma. Represents nerve dysfunction without substantial anatomic damage.
Concussion
Brain injury: How will a patient present with a concussion?
- Transient episode of neuronal dysfunction (confusion, disorientation, event amnesia)
- Followed by a rapid return to normal neurologic activity
Brain injury: A ___, ___, ___ ___, ___ ___, and ___ ___ may occur alone or in combination.
concussion, contusion, intracerebral hemorrhage, subdural hematoma, and epidural hematoma
Brain injury: What is a moderate DAI?
Shearing, stretching, or tearing of the axon occurs, but minute bruising of brain tissue occurs too; referred to as “classic concussion”
Brain injury: Occurs in 20% of all severe head injuries and comprises 45% of all DAI cases; Moderate DAI is commonly associated with ___ ___ fracture.
Basilar skull
Brain injury: What are signs and symptoms of moderate DAI?
- Immediate unconsciousness
- Followed by persistent confusion
- Inability to concentrate
- Disorientation
- Retro-/anterograde amnesia
- Patient may complain of headache, focal neurologic deficits, light sensitivity (photophobia), and disturbances to smell and other senses
- Anxiety
- Significant mood swings
Brain injury: What is severe DAI?
Previously known as brainstem injury; significant mechanical disruption of many axons in both cerebral hemispheres with extension into brainstem
Brain injury: approximately 16% of all severe head injuries and 36% of all DAI cases are classified as severe. Many patients don’t survive this type of injury; those that do have some degree of permanent ___ impairment.
Neurologic
Brain injury: How does a patient present with severe DAI?
Unconscious for prolonged period of time and displays signs of increased ICP (Cushing’s response and decerebrate or decorticate posturing)
Brain injury: What are indirect (or secondary) injuries?
Result of factors that occur because of (though after) the initial/primary injury; processes are progressive and cause the patient deterioration often associated with serious head injuries
Brain injury: What are the two pathological processes that cause indirect injuries?
(1) Diminishing circulation to brain tissue (intracranial perfusion) due to increasing intracranial pressure and possible exacerbated by hypoxia/hypercarbia/systemic hypotension
(2) Progressive pressure against - or physical displacement of - brain tissue secondary to an expanding mass within the cranium
BOTH pathologies continue and expand nervous tissue injury and cause some of the specific/progressive signs and symptoms associated with head injury
What is the one of the body’s most perfusion-sensitive organs?
The brain
Brain injury: Cranial volume is fixed and does not vary. Any increase in the size by one component must be matched by a similar ___ in another component otherwise the ___ ___ will rise.
reduction ; intracranial pressure (ICP)
*** The cerebrum, cerebellum, and brainstem account for 80% (1,200 mL). Venous, capillary, and arterial blood accounts for about 12% (150 mL). Cerebrospinal fluid accounts for the remaining 8% (90 mL).
Brain injury: What is the first means of compensating for expansion in the cranium?
Compression of the venous blood vessels
Brain injury: What is the second means of compensating for expansion in the cranium?
Cerebrospinal fluid is bused out of the cranium and into the spinal cord
Brain injury: What happens once the components reach their compensatory limits in the cranium?
- Intracranial pressure rises quickly and begins to restrict arterial blood flow
- Reduction in cerebral blood flow triggers a rise in systemic B to ensure adequate cerebral perfusion (known as autoregulation)
- The greater the pressure of arterial blood flow, the greater the ICP which further increases the resistance to cerebral blood flow
- —This produces more hypoxia and hypercarbia
- Cycle continues
Brain injury what is another factor affecting ICP and circulation throught eh brain?
Level of carbon dioxide in CSF
Brain injury: The brain’s response to high ___ ___ concentrations and the increasing ___ causes the classical ___ and ___ associated with head injury.
carbon dioxide ; ICP ; hyperventilation ; hypertension
Brain injury: ___ is a valuable tool in the reassessment of head injury patients especially if you’re ventilating them.
Capnography
Low ___ ___ and poor ___ ___ seriously compound any existing head injury.
blood pressure ; respiratory exchange
Diminished cerebral circulation causes increasing ___ (retained carbon dioxide) and ___ ___.
acidosis ; anaerobic metabolism
Brain injury: ___ (in response to increasing acidosis and carbon dioxide levels) elevates any existing intracranial pressure.
Vasodilation
Brain injury: If the compression results from a building mass along the central region of the cerebrum, pressure is first directed to the ___, then the ___, and finally to the ___ ___. The signs and symptoms of this progressive pressure and structural displacement are somewhat predictable and known as the ___ ___.
midbrain ; pons ; medulla oblongata ; central syndrome
Brain injury: In the central syndrome, upper brainstem compression produces an increase in BP to maintain cerebral perfusion pressure (called ___ ___) and a reflex decrease in heart rate in response to vagus nerve (parasympathetic) stimulate of the SA node and AV junction.
Cushing’s reflex
Brain injury: Central syndrome patients might also exhibit a characteristic cyclic breathing pattern called ___-___ ___. This consists of increasing, then decreasing, respiratory volumes, followed by a period of apnea.
Cheyne-Stokes respirations.
Brain injury: What is Cushing’s triad?
The combinations of increasing BP, slowing pulse, and erratic respirations in response to increased intracranial pressure
Brain injury: As the middle brainstem becomes involved the pulse pressure ___ and the heart rate becomes ___. Respirations now may be deep and rapid (___ ___ ___). Increasing ICP may also induce ___ sluggishness and nonreactivty (bilaterally since the pathology involves compression from above).
widens ; bradycardic ; central neurologic hyperventilation ; pupil
Brain injury: As the pressure reaches the lower brainstem the pupils become fully dilated and unresponsive. Respirations become ___ (erratic with no characteristic rhythm) or even cease. The ___ rate is often very irregular with great swings in rate. ECG conduction disturbances become apparent, including ___ complex, ___ segment, and ___ wave changes.
ataxic ; pulse ; QRS ; ST ; T
Brain injury: How can you asses whether a patient has cerebral herniation?
- Likely to display increasing BP, decreasing pulse rate, and respirations that become irregular (Cushing’s triad)
- May have a lowering level of consciousness (Glasgow Coma scale
Brain injury: How does pediatric head trauma differ from older patients?
Generally the softer skeletal structure increases the direct injury associated with head trauma (in the very young pediatric patient) but slows the progression of increasing ICP
Brain injury: Intracranial hemorrhage may significantly contribute to ___ in pediatric patients.
Hypovolemia
Brain injury: What is the standardized evaluation tool used to measure a patent’s level of consciousness by assessing and awarding points for the best eye opening, verbal, and motor responses?
Glasgow coma scale (GCS)
Brain injury: Why is it important to pay attention to a patient’s eye signs when evaluating them for possible head trauma?
- Eyes are specialized body tissue (like CNS tissue)
- Very visible special sense organ
- Give indications of problems with cranial nerves CN II, III, IV, and VI and with perfusion associated cerebral blood flow
- Pupil size and reactivity give clues (depressant drugs and cerebral hypoxia will reduce responsiveness while extreme hypoxia causes them to dilate and fix)
Brain injury: IF one pupil is fixed yet shows some response to consensual stimulation (light variations in the other eye), the problem most likely lies with the ___ ___.
oculomotor nerve
Facial injury: Why is facial injury a serious trauma complication?
- Cosmetic importance to people
- Region’s vasculature and location of the initial airway and alimentary canal structures and the organs of sight, smell, taste, and hearing present there
- Facial injuries suggest associated head and spinal injuries