Download - Ch08 head, face, and neck
Paramedic Care:Principles & Practice
Volume 5Trauma Emergencies
Head, Facial, and Neck Trauma
IMPORTANT CONCEPT #1
ETOH + TRAUMA (WITH OR WITHOUT AMS)
= CLOSED HEAD INJURY UNTIL PROVEN OTHERWISE
Anatomy and Physiology
Anatomy and Physiology
The Brain
Grand Central Station
Anatomy and Physiologyof the Head
CNS Circulation– Arterial
Four Major Arteries2 Internal Carotid Arteries2 Vertebral Arteries
Circle of WillisEncircle the base of the brain
– VenousDrain into internal jugular veins
What’ you talkin ‘bout Willis?
The Meninges and Skull
Anatomy and Physiology
Anatomy and Physiology
Blood-Brain Barrier– Less permeable than elsewhere in body– Does not allow flow of interstitial proteins– Reduced lymphatic flow– Very protected environment
Blood Brain Barrier
Proteins Glucose
More Math
MAPICPCPP
CPP
Cerebral Perfusion Pressure– Pressure within cranium (ICP) resists blood flow
and good perfusion to the CNSPressure usually less than 10 mmHg
– Mean Arterial Pressure (MAP)Must be at least 50 mmHg to ensure adequate perfusionMAP = DBP + 1/3 Pulse Pressure
– Cerebral Perfusion Pressure (CPP)Pressure moving blood through the craniumCPP = MAP - ICP
Monroe-Kelly Doctrine
Contents of the Skull–Brain–CSF–Blood–Expanding mass
Anatomy and Physiology
The Monroe-Kelly Doctrine– The ICP is dynamic
Constantly changing to variations in body physiology – Intracranial Volume (fixed) = Brain Volume + CSF
Volume + Blood Volume + Mass/Lesion Volume – Any added extrinsic factor that occupies space in
the cranial vault increases intracranial volume and pressure
Anatomy and Physiology
Monroe-Kelly Doctrine– Autoregulation
Changes in ICP result in compensationIncreased ICP = Increased BP
This causes ICP to rise higher and BP to riseBrain injury and death become imminent
– Expanding mass inside cranial vaultDisplaces CSFIf pressure increases, brain tissue is displaced
Anatomy and Physiology
Cranial Nerves
Face musclesM
Chewing musclesM
Posterior palate and pharynxM
Face musclesM
SightSOpticIIPupil Const, rectus and obliquesMOculomotorIII
Opthalmic (FH), Maxillary (cheek), Mandible (chin)STrigeminalV
Lateral rectus muscleMAbducensVI
Taste to posterior tongueSVagusX
TongueMHypoglossalXIITrapezius and sternocleido musclesMAccessoryXI
Hearing balanceSAcousticVIII
Superior obliquesMTrochlearIV
TongueSFacialVII
Posterior pharynx, taste to anterior tongueSGlossopharyn-gealIX
SmellSOlfactoryIInnervationFNameCN
Cranial Nerves
Anatomy and Physiologyof the Head
Anatomy and Physiology
Ascending Reticular Activation System– Tract of neurons in upper brainstem, pons, and midbrain– Responsible for sleep-wake cycle– Monitors input stimulation– Regulates body functions
RespirationHeart ratePeripheral vascular resistance
Anatomy and Physiology
Face Structure– Facial Bones
Zygoma
Maxilla
Mandible
Nasal bones
Anatomy PhysiologyFacial Structure– Covered with skin
Flexible and thinHighly vascular
– Minimal layer of subcutaneous tissue
Circulation– External carotid artery
Supplies facial areaBranches
Facial, temporal, and maxillary arteries
Anatomy and PhysiologyNasal Cavity– Upper Border
BonesJunction of ethmoid, nasal, and maxillary bones
Bony SeptumRight and left chamber
Turbinates– Lower Border
Bony hard palateSoft palate
Moves upward during swallowing– Nasal Cartilage
Forms nares
Anatomy and Physiology
Oral Cavity– Formed Structures
Maxillary bonePalateUpper teeth meeting the mandible and lower teeth
– FloorTongue
– MandibleArticulates with the TMJ joint
Anatomy and Physiology
Special Structures– Salivary Glands
First stage in digestionLocation
Anterior and inferior to the earUnder tongueInside the inferior mandible
– TonsilsPosterior wall of the pharynx
Anatomy and Physiology
Sinuses– Hollow spaces in cranium and facial bones– Function
Lighten headProtect eyes and nasal cavityProduce resonant tones of voiceStrengthen area against trauma
Anatomy and Physiology
Pharynx– Posterior and inferior to the oral cavity– Aids in swallowing
Bolus of food propelled back and down by tongueEpiglottis moves downwardLarynx moves up
Combined effect seals airway
Peristaltic wave moves food down esophagus
Anatomy and Physiology Ear– Function
HearingPositional sense
– StructuresPinna
Outer visible portionFormed of cartilage and has poor blood supply
External Auditory CanalGlands that secrete cerumen (wax)
Middle and Inner EarStructures for hearing and positional sense
Anatomy and Physiology Structures for HearingStructures for Proprioception– Semicircular
canalsSense position and motion
– Present when eyes are closed
– VertigoContinuous movement sensation
Anatomy and Physiology Eye
Anatomy and Physiology The Neck– Can be divided into three zones
Zone 1Zone 2Zone 3
Anatomy and Physiology
Vasculature of the Neck– Carotid Arteries
Arise fromBrachiocephalic arteryAorta SplitCarotid bodies and sinuses
Bodies: Monitor CO2 and O2 levelsSinuses: Monitor blood pressure
Anatomy and Physiology
Jugular Veins– External
Superficial, lateral to the trachea– Internal
Sheath with the carotid artery and vagus nerve
Anatomy and Physiology
Airway Structures– Larynx
EpiglottisThyroid and cricoid cartilage
– TracheaPosterior border is anterior border of esophagus
Anatomy and Physiology
Other Structures of the Neck– Cervical Spine
Musculoskeletal FunctionNervous Function
Anatomy and Physiology
Other Structures of the Neck– Esophagus– Cranial Nerves
CN-IX (Glossopharyngeal)Carotid bodies and carotid sinuses
CN-XSpeech, swallowing, cardiac, respiratory, and visceral function
– Thoracic DuctDelivers lymph to the venous system
Anatomy and Physiology
Other Structures of the Neck– Glands
ThyroidRate of cellular metabolismSystemic levels of calcium
– Brachial PlexusNetwork of nerves in lower neck and shoulder that control arm and hand function
Pathophysiology of Head, Facial, and Neck Injury
Pathophysiology of Head, Facial, and Neck Injury
Difficult to assess in the prehospital setting Commonly threaten life May expose victims to lifelong disability
Mechanism of Injury
Injuries to the head, neck, and face are divided by mechanisms of injury– Blunt Injury
Head injuries most frequently result from auto and motorcycle crashes The face is frequently subjected to blunt trauma The neck is anatomically well protected from most blunt trauma
– Penetrating InjuryUsually result from either gunshots or stabbings Other types of penetrating injuries
Head Injury
Defined as a traumatic insult to the cranial region– Result in injury to soft tissues, bony structures, and the
brain
Scalp InjuryCommon Injuries– Contusions– Lacerations– Avulsions
Significant hemorrhage may occurReconsider MOI for severe underlying problems
© Photo Researchers, Inc.
Cranial Injury
The skull does not fracture unless trauma is extremeTypes – Linear
Most common– Depressed– Comminuted– Basilar
Cranial Injury
Basilar Skull Fracture– Common type of
skull fracture – Signs of basilar skull
fracture vary with the injury’s location
– May permit cerebrospinal fluid to seep out
© Ray Kemp/911 Imaging
Brain Injury
“A traumatic insult to the brain capable of producing physical, intellectual, emotional, social, and vocational changes.” National Head Injury Foundation
Classification– Direct– Indirect
Direct Brain Injury
Caused by the forces of trauma and can be associated with a variety of mechanismsCoupContrecoup
Direct Brain Injury CategoriesFocal– Occur at a specific location in brain
Cerebral contusionIntracranial hemorrhage
Epidural hematomaSubdural hematoma
Intracerebral hemorrhage
Diffuse– Concussion– Moderate diffuse axonal injury– Severe diffuse axonal injury
Focal Brain Injury
Cerebral Contusion– Capillary bleeding into brain tissue– Common with blunt head trauma– May result from a coup or contrecoup mechanism – Localized form of the injury manifests with
dysfunctions related to the site of the injury
Focal Brain InjuryIntracranial Hemorrhage– Epidural Hematoma
Bleeding between dura mater and skullInvolves arteries
Middle meningeal artery most common
Rapid bleeding and reduction of oxygen to tissuesHerniates brain toward foramen magnumProgression is both rapid and life threatening
Focal Brain Injury
Intracranial Hemorrhage (cont.)– Subdural Hematoma
Bleeding between meningesSlow bleeding
Superior sagittal sinus frequently injured
Signs progress over several days
Slow deterioration of mentation
Focal Brain Injury
Intracranial Hemorrhage (cont.)– Intracerebral Hemorrhage
Ruptured blood vessel within the brainPresentation similar to stroke symptomsSigns and symptoms worsen over time
– Cerebral edema Inflammatory response allows fluid leakage
– HydrocephalusMay occur with hemorrhage into the subarachnoid space
HERNIATION
Diffuse Brain Injury
Due to stretching forces placed on axonsPathology distributed throughout brain– Frequently distributed throughout the brain and
thus is called diffuse axonal injury (DAI) Types– Concussion– Moderate diffuse axonal injury– Severe diffuse axonal injury
Diffuse Brain Injury
Concussion – Mild to moderate form of diffuse axonal injury – Nerve dysfunction without anatomic damage– Transient episode of
Confusion, disorientation, event amnesia– Suspect if patient has a momentary loss of
consciousness– Management
Frequent reassessment of mentationABCs
Diffuse Brain Injury
Moderate Diffuse Axonal Injury– Stretching and tearing of neurons with minute
bruising of brain tissue – Unconsciousness
If cerebral cortex and RAS involved– Commonly associated with basilar skull fracture – Signs and Symptoms
Unconsciousness, persistent confusion, inability to concentrate, disorientation, and retrograde and anterograde amnesia
Diffuse Brain Injury
Severe Diffuse Axonal Injury – Significant mechanical disruption of axons
Cerebral hemispheres and brainstem– High mortality rate– Signs and Symptoms
Prolonged unconsciousnessCushing’s reflexDecorticate or decerebrate posturing
Indirect Brain Injury
Indirect (or secondary) injuries are the result of factors that occur because of, though after, the initial (or primary) injury Caused by two distinct pathological processes– Diminishing circulation to brain tissue due to an
increasing ICP– Progressive pressure against, or physical
displacement of, brain tissue
Intracranial Perfusion
Review– Cranial volume fixed
80% = Cerebrum, cerebellum, and brainstem12% = Blood vessels and blood8% = CSF
– Increase in size of one component diminishes size of another
Inability to adjust = increased ICP
Intracranial Perfusion
Compensating for Pressure– Compress venous blood vessels– Reduction in free CSF
Pushed into spinal cord
Decompensating for Pressure– Increase in ICP– Rise in systemic BP to perfuse brain
Further increase of ICPDangerous cycle
Intracranial Perfusion
Role of Carbon Dioxide– Increase of CO2 in CSF
Cerebral vasodilation
– Contributes to > ICP– Causes classic symptom
Hyperventilation and hypertension– Reduced levels of CO2 in CSF
Cerebral vasoconstrictionResults in cerebral anoxia
Factors Affecting ICP
Vasculature ConstrictionCerebral EdemaSystolic Blood Pressure– Low BP = Poor cerebral
perfusion– High BP = Increased ICP
Carbon DioxideReduced respiratory efficiency
IMPORTANT CONCEPT #2
HEAD INJURY + SHOCK = DEATH
Pressure and Structural Displacement
Increased pressure– Compresses brain tissue– Herniates brainstem
Compromises blood supply– Signs and Symptoms
Upper brainstemVomitingAltered mental statusPupillary dilation
Medulla oblongataRespiratoryCardiovascularBlood pressure disturbances
Signs and Symptoms of Brain Injury
Altered Mental Status– Altered orientation– Alteration in personality– Amnesia
RetrogradeAntegrade
Cushing’s Reflex– Increased BP– Bradycardia– Erratic respirations
Vomiting– Without nausea– Projectile
Body temperature changesChanges in pupil reactivityDecorticate posturing
Signs and Symptoms of Brain Injury
Physiological Changes– Frontal Lobe Injury
Alterations in personality– Occipital Lobe Injury
Visual disturbances– Cortical Disruption
Reduced mental status or amnesiaRetrograde
Unable to recall events before injury
AntegradeUnable to recall events after trauma“Repetitive questioning”
– Focal DeficitsHemiplegia, weakness, or seizures
Central Syndrome Progressive pressure and structural displacement are somewhat predictable – Known as Central Syndrome
Physiological Changes – Upper Brainstem Compression
Increasing blood pressureReflex bradycardia
Vagus nerve stimulation
Cheyne-Stokes respirationsPupils become small and reactiveDecorticate posturing
Central SyndromePhysiological Changes (cont.)– Middle Brainstem Compression
Widening pulse pressureIncreasing bradycardiaCNS hyperventilationBilateral pupil sluggishness or inactivityDecerebrate posturing
Central SyndromePhysiological Changes (cont.) – Lower Brainstem Injury
Pupils dilated and unreactiveAtaxic respirations
Erratic with no pattern
Irregular and erratic pulse rateECG changesHypotensionLoss of response to painful stimuli
Recognition of HerniationCushing’s Reflex– Increasing blood pressure– Decreasing pulse rate– Respirations that become erratic
Lowering level of consciousness – GCS <9 and dropping
Singular or bilaterally dilated and fixed pupilsDecerebrate or decorticate posturing No movement with noxious stimuli
Pediatric Head TraumaDifferent pathology than older patients– Skull can distort due to anterior and posterior
fontanellesBulgingSlows progression of increasing ICP
– Intracranial hemorrhage contributes to hypovolemia
Decreased blood volume in pediatrics
General Management– Avoid hyperextension of head
Tongue pushes soft palate closed– Ventilate through mouth and nose
Glascow Coma ScaleStandardized evaluation method – Used to
measure a patient’s level of consciousness
Assesses the best eye opening, verbal, and motor response
Eye Signs
Physiological Issues– Indicate pressure on
CN-II, CN-III, CN-IV, and CN-VI– Reduced peripheral blood flow
Pupil Size and Reactivity– Reduced pupillary responsiveness
Depressant drugs or cerebral hypoxia– Fixed and dilated
Extreme hypoxia
Facial InjuryFacial Soft-Tissue Injury– Highly vascular tissue
Contributes to hypovolemia– Superficial injuries are rarely life threatening– Deep injuries can result in blood being
swallowed and endanger the airway– Soft tissue swelling reduces airflow– Consider likelihood of basilar skull fracture or
spinal injury
Facial Injury
Facial Dislocations and Fractures– Common
FracturesMandibularMaxillary and Nasal
Le Fort I, II, and III Criteria
Orbit
Facial Injury
Nasal Injury– Rarely life threatening– Swelling and hemorrhage interfere with breathing– Epistaxis
Most common problem– Avoid nasotracheal intubation
Passage of ET tube into the cerebral cavity
Facial InjuryEar Injury– External Ear
Pinna frequently injured due to traumaPoor blood supplyPoor healing
– Internal EarWell protected from traumaMay be injured due to rapid pressure changes
Facial InjuryEye Injury– Foreign bodies– Corneal abrasions
and lacerations– Hyphema
Blunt trauma to the anterior chamber of the eye
– Sub-conjunctival hemorrhage
Less serious conditionMay occur after strong sneeze, severe vomiting, or direct trauma
Eye Injury (cont.)– Acute Retinal Artery Occlusion
Non-traumatic originPainless loss of vision in one eyeOcclusion of retinal artery
– Retinal DetachmentTraumatic originComplaint of dark curtain/obstruction in the field of viewPossibly painful depending on type of trauma
– Soft-Tissue Lacerations
Facial Injury
Neck Injury
Blood Vessel Trauma– Blunt trauma
Serious hematoma– Laceration
Serious exsanguinationEntraining of air embolism
Cover with occlusive dressing
Airway Trauma– Tracheal rupture or dissection from larynx– Airway swelling and compromise
Neck Injury
Cervical Spine Trauma– Vertebral fracture
Paresthesia, anaesthesia, paresis, or paralysis beneath the level of the injuryNeurogenic shock may occur
Subcutaneous emphysema– Tension pneumothorax– Traumatic asphyxia
Neck Injury
Penetrating trauma– Esophagus or trachea– Vagus nerve disruption
Tachycardia and GI disturbances– Thyroid and parathyroid glands
High vascular
Assessment of Head, Facial, and Neck Injuries
Assessment of Head, Facial, and Neck Injuries
Assessment follows the standard format – Size-up – Initial assessment – Rapid trauma assessment/focused exam and
history– Detailed assessment
Pay special attention to ensuring airway patencyConsider the need for rapid transport
Scene Size-Up
Consider the circumstances of injury Identify the nature and extent of forces that caused the injury – Spider-web windshield, deformity of the upper
steering wheel, helmet use in motorcycleRule out scene hazards
Initial Assessment
Form an initial impression – Be alert to the patient’s facial skin color,
respiratory effort, and to pupil luster and level of responsiveness throughout the initial assessment
Apply a cervical collar at the end of the initial assessment
Initial Assessment
Airway– Examine the face and neck for any deformity,
swelling, hemorrhage, foreign bodies, or other signs of injury
– Listen for unusual or changing voice patterns – Anticipate vomiting – Suctioning or intubation may worsen ICP
Initial AssessmentBreathing– Ensure that the patient is moving an adequate
volume of air – Head injury is likely to produce irregular breathing
patterns– Ventilations for the serious head injury patient
(GCS ≤8) are guided by capnography Maintain an end-tidal CO2 reading of between 35 and 40 mmHg For patients with suspected herniation, the end-tidal CO2 reading should range between 30 and 35 mmHg
– Apply oxygen via nonrebreather mask to the breathing patient
Initial Assessment
Circulation– Monitor the patient’s pulse rate and rhythm– Look for any hemorrhage from the head, face, and
neck and control any moderate to severe bleeding – Maintain a blood pressure of at least 90 mmHg
Rapid Trauma Assessment
A quick and directed head-to-toe examination of a patientManage any life-threatening injuries and conditions as you find them during the rapid trauma assessment – If the patient shows any signs of pathology within
the cranium, consider rapid transport
Head, Facial, and Neck Injury Management
Head, Facial, and Neck Injury Management
Management priorities for the patient sustaining head, face, or neck trauma include:– Maintaining the patient’s airway and breathing– Ensuring circulation through hemorrhage control– Taking steps to avoid hypoxia and/or hypovolemia – Providing appropriate medications
Head, Facial, and Neck Injury Management
Airway– Patients may be unable to control the airway
Altered level of consciousnessDamaged airway structures
– Sellick’s manuever– Suctioning
May increase ICPEmesis is common with head injury
Head, Facial, and Neck Injury Management
Airway (cont.)– Patient positioning
Initial left-lateral recumbancy with cervical precautions, if possibleApproximately 30° elevation of head of spine board
– Basic airway adjunctsOro and nasopharyngeal airwaysBe prepared for emesis
Endotracheal Intubation
OrotrachealDigitalNasotrachealRetrograde DirectedRapid Sequence
Head, Facial, and Neck Injury Management
Airway (cont.)– Cricothyrotomy
Needle cricothyrostomy and the open cricothyrotomy
Head, Facial, and Neck Injury Management
Breathing– Oxygenation
Any indication of lowered level of consciousness, orientation, or arousal is a candidate for high-flow, high-concentration oxygen
– VentilationAvoid hyperventilation
Decreased CO2 results in vasoconstrictionMaintain an end-tidal CO2 reading of between 35 and 40 mmHg
Head, Facial, and Neck Injury Management
Circulation– Control hemorrhage
An open neck injury carries the risk of air entering the external jugular
– Blood pressure maintenanceGuard against hypotension Maintain systolic BP at 90 mmHg
Medications
Oxygen– First-line drug– There are no contraindications nor side effects of
concern for use of oxygen during prehospital emergency care
Medications
Diuretics– Mannitol
Osmotic diuretic Draws water from the interstitial space and into the cardiovascular system
– Use may reduce ICP– Contraindications
Renal failureHypotension
– Slow IV bolus of 0.25 to 1 g/kg over 10 to 20 minutes
Medications
Paralytics– Drugs that paralyze the skeletal muscles,
permitting intubation in patients with whom the procedure would otherwise be impossible
Rapid Sequence IntubationUses etomidate, diazepam, midazolam, fentanyl, or morphine sulfate to sedate the patient Succinylcholine chloride, atracurium, or vercuronium to paralyze the patient
Medications
Dextrose– Hypoglycemia and hyperglycemia are detrimental
to the patient with head injuryIdentify the blood glucose level on all unresponsive patients
– If significant hypoglycemia is found, administer 25 mg of glucose and 100 mg of thiamine
Medications
Thiamine– Substance obtained from diet and needed for
body metabolism – In malnourished patients (like the chronic
alcoholic), thiamine is depleted Glucose cannot be convertedBrain is very sensitive to lack of Glucose
Medications
Topical Anesthetic Spray– Reduces the gag reflex, making endotracheal
intubation easier Reduces the impact retching has on intracranial pressure
– Effects of the agent are immediate (within 15 seconds), remain local, and last for about 15 minutes
Transport Considerations
Limit external stimulation– Can increase ICP– Can induce seizures
Be cautious about air transport– Seizures
Emotional Support
Have friend or family provide constant reassuranceProvide constant reorientation to environment if required– Keeps patient calm– Reduces anxiety
Special Injury Care
Scalp Avulsion– Cover the open wound with bulky dressing– Pad under the fold of the scalp– Irrigate with NS to remove gross contamination
Special Injury CareEye Injury– General Injury
Cover injured and uninjured eyePrevents sympathetic motion
Consider sterile dressing soaked in NS– Corneal Abrasion
Invert eyelid and examine eye for foreign bodyRemove with NS-moistened gauze or Morgan’s lens
– Avulsed or Impaled EyeCover and protect from injury
– General CareCalm and reassure patient
Special Injury Care
Dislodged Teeth– Rinse in NS– Wrap in NS-soaked gauze
Impaled Objects– Secure with bulky dressing– Stabilize object to prevent movement– Indirect pressure around wound