Vol.4-Ch.6 "Head, Neck, and Spinal Trauma" Flashcards
What 3 structure help to protect the brain?
- scalp
- cranium
- meninges
What does SCALP stand for and help you remember?
It is for the layers of ski protecting the scalp
Skin Connective tissue Aponeurotica Layer of subaponeurotica (areolar) tissue Pericranium (the skills periosteum)
What are the two main components of the cranium?
The cranium or cranial vault (where the brain is)
and the facial bones
What are the 3 layers of the meninges? describe them
Dura Mater - furthest from brain, has 2 layers: outer called periosteum and is attached to bone, inner is tough connective tissue that forms partial structural divisions
Pia Mater - closest to brain, highly vascular
Arachnoid membrane - covers inner dura matter and suspends brain with collagen and elastin fibers. Beneath is is the Subarachnoid Space that contains cerebrospinal fluid
What is cerebrospinal fluid and where does it come from?
It is a clear, colorless solution of water, proteins, and salts made to absorb shock.
It is made by the choroid plexus within the ventricles of the brain.
How much space does the brain, blood/vessels, and CSF take up in the cranial vault? What are the 3 main sections of the brain?
brain - 80%
Blood/vessels - 12%
CSF - 8%
- cerebrum
- cerebellum
- brainstem
What makes up the cerebrum and what does it control?
It is the largest nervous system element and takes up the most space
It has an exterior which directs motor, sensory, memory, and emotions
the Occipital region controls sight
the Temporal region controls long term memory, hearing, speech, taste, and smell
What structure divides the brain into right and left hemispheres?
the Falx Cerebri
What separates the cerebrum from the cerebellum?
the Tentorium Cerebelli
What does the cerebellum control?
fine motor movements and balance/maintenance of muscle tone
What 3 structures make up the brain stem?
- Midbrain (hypothalamus, and thalamus)
- Pons
- Medulla Oblongata
What does the hypothalamus control? Thalamus?
Hypothalamus : endocrine function, vomit reflex, hunger, thirst, kidney function, body temp, emotions
Thalamus : switching center between pons and cerebrum and is critical for the system that controls consciousness
What does the Pons do?
controls sleep
What 3 major centers does the medulla oblongata control?
- Respiratory Center
- Cardiac Center
- Vasomotor Center
What 4 major vessels supply blood to the brain?
What is the Circle of Willis?
2 Internal Carotid arteries and 2 Vertebral arteries (the 2 vertebral combine to form the basilar artery)
The circle of Willis is at the base of the brain and is where the carotid and basilar arteries interconnect
What is the blood brain barrier?
it refers to the fact that the nervous system capillary walls are thicker so that it is less permeable because if blood or other things leaked through it acts as an irritant to CNS tissue and can cause inflammation and edema
What is normal ICP?
Less than 10 mmHg
What is the Monroe-Kelly Doctrine?
the formula for the relationships that form ICP
Intracranial Volume = Brain Volume + CSF Volume + Blood volume
and states that if any of these go up, others must go down you you will have an increased ICP
What are the 12 cranial nerves?
CN-I = Olfactory (smell) CN-II = Optic CN-III = Oculomotor CN-IV = Trochlear (keep eyes moving together) CN-V = Trigeminal (facial senses and chewing) CN-VI = Abducens (downward eye movement) CN-VII = Facial CN-VIII = Acoustic CN-IX = Glossopharyngeal (swallowing, baroreceptors) CN-X = Vagus (PNS, heart, respiration) CN-XI = Spinal Accessory (neck,swallowing,vocal chords CN-XII = Hypoglossal (voluntary control of toungue)
What is the Ascending Reticular Activating System?
controls the sleep-wake cycle and plays a role in regulating respirations, heart rate, and peripheral vascular resistance
In the ear, what is responsible for hearing and what is responsible for sensing position/motion?
The inner ear receives sounds and the semicircular canals sense position and motion
What major blood vessels run along the neck?
The carotid arteries and the jugular veins
What are the three zones of the neck?
Zone 1 is below the cricoid ring (highest mortality rate)
Zone 2 is above the cricoid ring but below the angle of the jaw (more commonly injured)
Zone 3 is is above the angle of the jaw (injuries may be hidden but serious)
What are the 5 sections of the spine and how many vertebra are in each?
Cervical - 7 Thoracic - 12 Lumbar - 5 Sacrum - 5 (fused) Coccyx - 4 (fused)
What structure separates each vertebra?
Intervertebral disks
What is the first cervical vertebra called and why is it special?
It is the Atlas, it has no spinous process or vertebral body and permits nodding of the head (not twisting)
(this joint is called the atlantoocipital joint)
What is the 2nd cervical vertebra called and why is it special?
It is called the Axis and allows the head to swivel side to side
What are the 3 important ascending (sensory) tracts in the spinal column?
- Fasciculus Gracilis
- Fasciculus Cutaneous
- Spinothalamic
the first two relay sensory light touch, vibrations, positional sense from the skin, muscles, tendons, and joints to the brain.
Spinothalamic has two parts: the anterior tract conducts pain and temperature. the lateral tract conducts touch and pressure sensation
What is the important descending (motor) spinal nerve?
The Corticospinal Tract and is responsible for voluntary and fine muscle movement
Where does the spinal cord get its blood supply?
1 anterior spinal artery and 2 posterior spinal arteries
What are the two types of brain injurie categories?
Direct (primary) or indirect injury to the tissues of the cerebrum, cerebellum, or brain stem
What is the difference between coup and contrecoup brain injury
Coup is when the brain hit the front of the head (assuming impact came from the front) as the skull is moving backwards
Contrecoup is when the brain hit the back of the skull once the head stops going back but the brain continues and thus hits the back of the head which then stops the brain from moving
What are the two types of direct brain injuries? what are they?
Focal : injuries that occur at specific locations
Diffuse (DAI - diffuse axial injury): generalized mechanism of injury
What are 2 types of (direct) focal brain injuries? describe them.
Cerebral Contusion :
- when blunt trauma occurs it can produce capillary bleeding into the brain’s substance (often to frontal lobe which can cause personality changes)
Intracranial Hemorrhage :
- Can be an epidural hematoma, subdural hematoma, and intracerebral hemorrhage
Explain where an epidural hematoma is and describe it
It is between the dura mater and the skull.
These typically involve arteries and will develop and worsen fast
Explain where an subdural hematoma is and describe it
It is between the dura mater and the arachnoid space
This occurs very slowly because they involve small venous vessels, since it is still above the pia mater it does not touch the brain tissue and cause irritation, inflammation and ultimately swelling like in intracerebral bleeding
suspect this with Pts who have not had recent trauma but present neurological deficiencies, take through history looking for previous trauma over some time ago
Explain where intracerebral hemorrhage occurs and describe it
Occurs when bleeding is directly on the brain surface which causes irritation, inflammation and ultimately swelling. This will happen fast because it usually involves and artery and will present much like a stroke
What is hydrocephalus?
It is a byproduct of intracerebral hemorrhaging where swelling or fluids block the arachnoid villi in the subarachnoid space that are responsible for allowing CSF to be reabsorbed back into the blood. This obviously causes increased ICP
What are 3 types of (direct) diffuse brain injuries? (DAI - diffuse axial injury)
Concussion : (mild DAI)
- is when there is nerve dysfunction without substantial anatomic damage. Pt usually has confusion, disorientation, and event amnesia
Moderate Diffuse Axial Injury (DAI): “classic concussion”
- caused by stretching, tearing, or shearing of nerve fibers with minute brain bruising. Pt may (usually) loose consciousness and have prolonged confusion, lack of concentration, disorientation, and amnesia
Severe Diffuse Axial Injury (DAI) :
- caused by significant mechanical disruption of multiple axons in both cerebral hemispheres and extends to brain stem. Pt will usually remain unconscious and many do not survive; of those who do they will have permanent neurological deficiencies
What is indirect injury and what are 2 distinct ones?
Indirect injury (secondary) is the result of factors that occur because of the initial (primary) injury
- Intracranial Perfusion
- Pressure & Structural Displacement
What are 2 major factors that affect brain perfusion?
ICP and hypotension
Since veins are the first thing to compress when ICP goes up (the next being CSF being pushed into the spinal cord) what will take place in response to the low venous blood return?
It will cause a build up of CO2 (hypercarbia) which will cause vessels to dilate, increasing ICP even further. This increase in ICP and CO2 build up is the cause of hyperventilation and hypertension associated with head injuries.
The latter is for HYPERcarbia but HYPOcarbia can be just as dangerous because it will cause vasoconstriction but this will further decrease blood supply to the brain
What symptoms would be present if the brain stem was herniated through the tentorium incisura?
what about the medulla oblongata through the foramen magnum
Brain stem herniation = vomiting, AMS, pupillary dilation
Medulla Oblongata herniation = disturbance in breathing, blood pressure, and heart rate
What are 8 signs and symptoms of a brain injury?
1) Altered Mental Status
2) Altered personality
3) Amnesia (event, retro = before event, antero = after)
4) Cushing’s Triad
5) Vomiting
6) Body temp changes
7) Pupillary reaction change
8) Decorticate posturing
What is Cushing’s Triad? Compression of what causes this?
- Increased BP
- slow pulse
- Irregular respirations
compression of the brain stem
What is the “central syndrome”?
The predictable progression of events caused by an expanding mass in the central cerebrum that puts pressure on the midbrain, then pons, then medulla oblongata
What are some mechanisms of spinal injury?
Extreme range of motions including:
- Hyperextension/flexion
- rotational
- lateral
Axial Stress:
- loading (compression)
- distraction (decompression)
What are 6 types of spinal cord injuries?
- Concussion (disruption but no damage)
- Contusion (minor damage and bruising/fluid leakage)
- Compression
- Laceration
- Hemorrhage
- Transection (partial or full cut of the chord)
What are 9 signs and symptoms of spinal chord injuries?
- Paralysis of extremities
- Pain w/out movement
- Tenderness of spine
- Impaired breathing
- Spinal Deformity
- Priapism
- Posturing
- Loss of bowel/bladder control
- Nerve impairment to extremities
What causes Anterior Cord Syndrome?
Central Cord Syndrome?
Brown-Sequard Syndrome?
Cauda Equina Syndrome
Anterior Cord Syndrome = flexion/extension injury and results from bony fragments or pressure compressing arteries that perfuse the anterior cord
Central Cord Syndrome = hyperextension of spine often with preexisting arthritis, affects 50+yo via incontinence and motor weakness in lower extremities
Brown-Sequard Syndrome = penetrating injury to one side of the chord that effects the ipsilateral side of the body to the injury
Cauda Equina Syndrome = is when the lower end of the spinal cord are compressed, interrupting sensation and motor control, especially bladder and bowel nerves
What is spinal shock?
temporary insult to the spinal cord affecting body below the level of injury; the affected area becomes flaccid and loses feeling
transient = ?
temporary
What is a SCIWORA and who does it affect?
it affects young children who have much more elastic spines and ligaments. A Spinal Cord Injury With Out Radiographic Abnormality (SCIWORA) occurs when there is a spinal cord injury but xrays show no sign of spinal column because they were unharmed thanks to their stretcher nature as opposed to the spinal cord
What is retroauricular ecchymosis? What is it a sign of?
It is also called “Battle’s Sign” and it is a black and blue discoloration found just behind the ears and it is an indication of a Basilar Skull fracture
What is bilateral periorbital ecchymosis? What is it a sign of?
It is also called “Racoon Eyes”, it is a severe discoloration around the eyes associated with orbital fractures and a classic sign of a Basilar Skull fracture
What are 4 types of cranial fractures? Describe them,
- Linear Nondisplaced Fracture: small cracks in the cranium, with no other associated injuries this is not particularly harmful for Pt.
- Depressed Fracture : is an inward displacement of the skull
- Open Fracture : involves the cranium and often the dura mater being broken and exposed
- impaled object : self explanatory
What is the thinnest most frequently fractured cranial bone?
Temporal
What is the target or “halo” sign?
It is the yellowish ring around blood caused by CSF, commonly from the ears (though can also come from eyes, nose, or mouth), is a common sign of a basilar skull fracture, CSF leakage should not try to be stopped as it is often releasing ICP and helping lessen damage to the brain. The body reproduces CSF very quickly
What are the 4 types of scalp injuries? describe them.
- Hematoma : blow disrupts blood vessels causing blood to accumulate and swell making a bump
- Depression : blow can tear fascial layers under neath causing a depression; this can often be confused with a depressed skull fracture but it is not
- Normal Scalp Contour : blood may fill the space vacated by the torn fascia; basically a depression but blood fills the dent so it appears normal
- Depressed fracture : Like the last two but this time a fracture is present but that blood still fills the dent, masking the skull fracture
What are two immediate problems caused by a facial injury and what 2 associated injuries should be assumed?
A mass loss of blood because of high vasculature (hypovolemia) and a compromised airway
Assume a head and spinal injury to be associated
What 4 places are facial fractures or dislocations often found?
- Mandible
- Maxillary
- Orbital
- Nasal
What are Le Fort’s Facial Fractures? for what bone?
The classify maxillary damage
Le Fort I : slight instability to maxilla, no displacement
Le Fort II : Fracture of both maxilla and nasal bones
Le Fort III : Fracture involving entire face below brow ridge ( zygoma, nasal, maxilla)
** Le Fort II & III can cause CSF leakage
Epistaxis (nosebleed) can be classified as either _____ or _____?
Anterior - comes out of the nasal septum, usually from damage to a network of vessels called Kiesselbach’s plexus
Posterior - goes down back of Pts throat and can cause nausea or vomiting
What is hyphema?
What is subconjunctival hemorrhage?
What is enophthalmos?
Hyphema is the pooling or collection of blood over the iris or pupil (usually involves hospitalization and intervention)
Subconjunctival hemorrhage is when small blood vessels in the subconjunctiva rupture leaving a portion of the eye surface to turn blood red (not serious)
Enophthalmos - is the depression displacement injury of something like a racquet ball hitting the eye directly and pushing it back
What is the Simplified Motor Score (SMS) and when is it done?
It is a simplified GCS that can be done early and very quickly in the primary assessment to assess possible brain injury
It only entails:
2 = obeys commands
1 = localizes pain (actually moves towards pain stim)
0 = withdrawals to pain or worse
a score of 1 means transport to neuro center
a score of 0 mean intubate
If the heart rate is _____ and _____ then suspect brain injury
below 60 and strong/bounding
normal is 60-100
If a Pt has a head injury WITH suspected herniation, adjust capnography goals from 35-40mmhg (normal) to _____?
30-35mmHg to help prevent hypercarbia
What set of vitals is the sign for a herniated brain injury?
as ICP goes up it will eventually cause herniation so it is also a sign of increased ICP as well
Cushing’s Triad:
- increased systolic BP (strong and bounding pulse)
- slow and decreasing pulse rate
- Irregular respirations (typically cheyne-stokes respirations that is increasing then decreasing resp volumes followed by periods of apnea)
they will also typically have irregular pupil reactions, posturing (decorticate or decerebrate), or no movement at all
Usually the affected pupil is on the _____ side as the brain injury side
Ipsilateral (same side)
What is the Doll’s eye (oculocephalic) response?
Tests for a brain injury by rotating the head side to side. At normal the eyes will move slowly with the head, but if a brain injury is present the eyes will move with the head (or in other words not move at all, just point where the head is pointing)`
DO NOT do if there is suspected spinal injury
The eyes can provide indications of problems with cranial nerves? (4)
CN - II (optic)
CN - III (oculomotor)
CN - IV (Trochlear) (keeps eyes moving together)
CN - V (Trigeminal) (sensations of face, teeth, gums, palate, and controls chewing)
When doing a full body exam on a Pt you suspect has a brain/CNS injury and suspected paralysis or loss of feeling/function, what should you change?
Start from feet and move upwards, this sis to prevent the patient from realizing they have lost their ability to feel and may panick
Also be on the look out for where the line between sensation and no sensation is as well as where skin may go from cold and pale to warm and flush. This also indicates that CNS has lost its ability to control the vasculature there
With a traumatic brain injury, it is critical to maintain a BP of at least _____ mmHg with aggressive fluid resuscitation?
90
What does a GCS of 13-14 mean?
9-12?
Less than 8
3-15 is total range
13-14 means mild head injury
9-12 means moderate injury
Less than 8 means severe injury and usually means coma and probably intubation
What are the 3 things GCS weighs?
If a pt has a score of anything less than ____ reassess every _____ minutes
- Eye Response
- Verbal Response
- Motor Response
If a pt has anything less than a 15 (perfect score) reassess their GCS every 5 minutes
What scores can you get for Eye Movement in GCS?
Eye Movement:
4 = Spontaneous 3 = to Verbal Command 2 = to Pain 1 = No Response
What scores can you get for Verbal Response in GCS?
Verbal Response:
5 = Oriented and converses normally 4 = disoriented but converses 3 = Inappropriate words (random words) 2 = incomprehensible sounds 1 = no response
What scores can you get for Motor Response in GCS?
Motor Response:
6 = Obeys verbal commands 5 = Localizes pain 4 = Withdrawals from pain (flexion) 3 = Abnormal flexion to pain (decorticate rigidity) 2 = Abnormal extension to pain (decerebrate rigidity) 1 = No response
What is a priapism, what is it a sign of?
What is the “hold-up” position? What is it a sign of?
A priapism is an erection caused from unopposed parasympathetic stimulation; which happens when a brain injury blocks the sympathetic tone
The “hold-up” position is when the Pt holds their hands/arms above the shoulders and head because spinal injury has caused them to loose control over their adductor and extensor muscles but maintains control over their abductor and flexors
In the event a traumatic brain injury causes seizures, what meds can you consider giving? (2)
Diazepam and lorazepam
What is a eye(s) that looks dull and lackluster a sign of?
What does it mean when one pupil becomes sluggish, nonreactive, then dilated?
Cerebral hypoxia
increased ICP
What should be kept aligned when moving a patient?
Nose, navel, and toes
What 3 criteria must be met in order to discontinue spinal precautions?
1) Pt must be fully oriented, not intoxicated, has GCS of 15, and is not effected by the fight or flight response
2) The Pt is free of significant distracting injuries
3) Pt is free of any signs or symptoms of spinal injury
According to the Maine spinal clearance protocol, what 4 things can individually or together suggest immobilization is necessary?
1) Unreliable Pt
2) Distracting injury is present
3) Abnormal sensory/motor exam
4) Sine pain/tenderness
According to the Nexus spinal clearance protocol, what 5 things can individually or together suggest immobilization is necessary?
1) if mid-line C-spine is tender
2) if any neurological deficient are present
3) if Pt has anything less than a 15 GCS
4) if Pt is intoxicated
5) if the Pt has distracting injury or pain
What is different about the Canadian C-spinal clearance protocol, in contrast to Maine or Nexus?
It weighs the mechanism of injury, not the pain/injury
If you have a Pt that is hypertensive and has a suspected brain injury, what is the only thing you can do?
Elevate the head 30 degrees
What kind of drug is Diazepam (Valium)?
What is it good for?
How long does it last?
Diazepam, Lorazepam, and Midazolam can be reversed by giving what drug?
Diazepam:
Is a benzodiazepine; it has antianxiety and muscle relaxant qualities
It is often used for PREMEDICATION for INTUBATION and as a potent ANTICONVULSANT
It is fast acting, taking peak effectiveness in 15 minutes and lasting up to 60 minutes
**Diazepam, Lorazepam, and Midazolam can be reversed by giving FLUMAZENIL
How does Lorazepam (Ativan) differ from Diazepam?
It is one of the most potent benzodiazepines; however, has a shorter lasting sedation effect but longer anti-seizure effect
Other than those regards it is very similar to diazepam
Of the three Analgesics WITH sedative properties discussed, which one is the best for a head trauma Pt and why?
- Morphine
- Fentanyl
- Ketamine
Fentanyl is the best for a head injury, it is an opiate narcotic (easily reversible with Naloxone (narcan), it has a faster onset action than morphine so lower dosages are needed but most importantly it does NOT cause hypotension as badly as morphine
Morphine is not a good candidate mostly because it has side effects such as: HYPOtension, respiratory depression, and possible nausea and vomiting. It is an opium alkaloid and does relieve pain, sedates, and reduces anxiety. (hypotension is caused by a reduction in cardiac preload caused by an increase in venous capacitance) (i.e. it blows up veins which decreases pressure of veins pushing blood back to the heart, effectively decreasing preload and thus output of the heart)
Ketamine is an analgesic and sedative but adversely causes HYPERtension and tachycardia which can be contraindicated for head trauma Pts that typically can already have hypertension (this will just increase ICP further)
What meds were previously used and now no longer used in spinal cord injuries?
Corticosteroids, they use to combat the inflammation but had too many side effects
How can you medicinally combat the hypovolemia and slow heart rate often found with brain injuries?
Hypovolemia is combated with fluid therapy and if needed vasopressors such as dopamine, norepinephrine, or phenylnephrine
Bradycardia is combated with Atropine, via reducing parasympathetic stimulation
What effects can Mannitol have that would be helpful or hurtful for a brain injury pt?
Mannitol is a osmotic diuretic, so it draws in water from the interstitial spaces and into the cardiovascular system.
This can be beneficial for a Pt with high ICP that is herniating or that has cerebrum edema because it will draw in fluids from the cerebrum
CONTRAINDICATIONS however are if a Pt has lower than 90mmHg as it will further reduce blood pressure and for Pts with kidney problems as the kidneys have to flush out and filter all the reabsorbed water
Cerebral Perfusion Pressure (CPP) =
CPP = MAP - ICP
For the patient with suspected traumatic brain injury, the ideal positioning of the patient for transport is:
on a long backboard with the head of the backboard elevated 15 to 30 degrees.
The spinal cord is continuous from the brain to the level of?
L1 to L2
What is the desired range of end tidal CO2 on capnography for Pt WITH suspected herniation?
30-35
