Trauma CNS Injury - Bristol North EMS

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Trauma
CNS Injury - Concussion
Cranial Injury
 Trauma must be extreme to fracture
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Linear
Depressed
Open
Impaled Object
 Basal Skull
 Unprotected
 Spaces weaken
structure
 Relatively
easier to fracture
Cranial Injury
 Basal Skull Fracture
Signs
 Battle’s Signs
 Retroauricular Ecchymosis
 Associated with fracture of
auditory canal and lower
areas of skull
 Raccoon Eyes
 Bilateral Periorbital
Ecchymosis
 Associated with orbital
fractures
Cranial Injury
 Basilar Skull
Fracture
 May tear dura
 Permit CSF to drain
through an external
passageway
• May mediate rise of ICP
• Evaluate for “Target” or
“Halo” sign
Brain Injury
 As defined by the National Head
Injury Foundation
 “a traumatic insult to the brain capable of
producing physical, intellectual, emotional,
social and vocational changes.”
 Classification
 Direct
• Primary injury caused by forces of trauma
 Indirect
• Secondary injury caused by factors resulting from the
primary injury
Direct Brain Injury Types
 Coup
 Injury at site of
impact
 Contrecoup
 Injury on
opposite side
from impact
Direct Brain Injury Categories
 Focal
 Occur at a specific location in brain
 Differentials
 Cerebral Contusion
 Intracranial Hemorrhage
• Epidural hematoma
• Subdural hematoma
 Intracerebral Hemorrhage
 Diffuse
 Concussion
 Moderate Diffuse Axonal Injury
 Severe Diffuse Axonal Injury
Focal Brain Injury
 Cerebral Contusion
 Blunt trauma to local brain tissue
 Capillary bleeding into brain tissue
 Common with blunt head trauma
 Confusion
 Neurologic deficit
• Personality changes
• Vision changes
• Speech changes
 Results from
 Coup-contrecoup injury
Focal Brain Injury
Intracranial Hemorrhage
 Epidural Hematoma
 Bleeding between dura
mater and skull
 Involves arteries
 Middle meningeal artery
most common
 Rapid bleeding &
reduction of oxygen to
tissues
 Herniates brain toward
foramen magnum
Focal Brain Injury
Intracranial Hemorrhage
 Subdural
Hematoma
 Bleeding within meninges
 Beneath dura mater &
within subarachnoid
space
 Above pia mater
 Slow bleeding
 Superior sagital sinus
 Signs progress over
several days
 Slow deterioration of
mentation
Focal Brain Injury
Intracranial Hemorrhage
 Intracerebral Hemorrhage
 Rupture blood vessel within the brain
 Presentation similar to stroke symptoms
 Signs and symptoms worsen over time
Diffuse Brain Injury
 Due to stretching forces placed on
axons
 Pathology distributed throughout
brain
 Types
 Concussion
 Moderate Diffuse Axonal Injury
 Severe Diffuse Axonal Injury
Diffuse Brain Injury
Concussion
 Mild to moderate form of Diffuse Axonal
Injury (DAI)
 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 mentation
 ABC’s
Diffuse Brain Injury
Moderate Diffuse Axonal Injury
 “Classic Concussion”
 Same mechanism as concussion
 Additional: Minute bruising of brain tissue
 Unconsciousness
 If cerebral cortex and RAS involved
 May exist with a basilar skull fracture
 Signs & Symptoms
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Unconsciousness or Persistent confusion
Loss of concentration, disorientation
Retrograde & Antegrade amnesia
Visual and sensory disturbances
Mood or Personality changes
Diffuse Brain Injury
Severe Diffuse Axonal Injury
 Brainstem Injury
 Significant mechanical disruption of
axons
 Cerebral hemispheres and brainstem
 High mortality rate
 Signs & Symptoms
 Prolonged unconsciousness
 Cushing’s reflex
 Decorticate or Decerebrate posturing
Intracranial Perfusion
 Review
 Cranial volume fixed
 80% = Cerebrum, cerebellum & brainstem
 12% = Blood vessels & blood
 8% = CSF
 Increase in size of one component diminishes
size of another
 Inability to adjust = increased ICP
ETCO2 Monitoring
Physiology of the
Respiratory System
Respiration and
Ventilation
 Respiration is the exchange of gases
between a living organism and its
environment.
 Ventilation is the mechanical process
that moves air into and out of the lungs.
The Respiratory Cycle
 Pulmonary ventilation depends upon
changes in pressure within the thoracic
cavity.
 Coordinated interaction among the
respiratory system, the central nervous
system, and the musculoskeletal system.
The Respiratory Cycle
 Inspiration
 Thoracic cavity is closed except for the
tracheal opening
 Respiratory centers stimulate nerves which
stimulate muscle
 Changes in pressure occur with
diaphragmatic contraction and intercostals
contract and air is drawn inward
 Active process
The Respiratory Cycle
 Expiration
 Receptors signal the respiratory center by
way of the vagus nerve to inhibit inspiration.
 Expiration occurs
 Normally passive
 Use of accessory muscles
Pulmonary Circulation
 Respiration also
requires an intact
circulatory system.
 Venous system
carries
deoxygenated blood
to the right side of
the heart, and the
right ventricle
pumps it into the
pulmonary
circulation.
Pulmonary Circulation
 Diffusion occurs
in the pulmonary
capillaries.
 Blood returns to
the left side of the
heart for systemic
circulation.
Diffusion
 Movement of a gas from an area of
higher concentration to an area of lower
concentration
 Transfers gases between the lungs and
the blood and between the blood and
peripheral tissues
Measuring Oxygen and
Carbon Dioxide Levels
 The partial pressure
of a gas is its
percentage of the
mixture’s total
pressure.
 Four major
respiratory gases:
 Nitrogen (N2)
 Oxygen (O2)
 Carbon dioxide
(CO2)
 Water (H2O)
Normal Arterial
Partial Pressures
Oxygen (PaO2) =
100 torr (average = 80 – 100)
 Carbon dioxide (PaCO2) =

40 torr (average = 35 – 45)
Factors Affecting Oxygen
Concentration in the
Blood
 Decreased hemoglobin concentration
 Inadequate alveolar ventilation
 Decreased diffusion across the
pulmonary membrane
 Ventilation/perfusion mismatch occurs
when a portion of the alveoli collapses
Factors Affecting Carbon Dioxide
Concentrations in the Blood
 Hyperventilation
 Lowers CO2 levels due to increased
respiratory rates or deeper respiration
 Increased CO2 production include:
 Fever, muscle exertion, shivering, and
metabolic processes
 Decreased CO2 elimination results from
decreased alveolar ventilation
Respiratory Rate
 Involuntary; however, can be voluntarily
controlled
 Chemical and physical mechanisms
provide involuntary impulses to
correct any breathing irregularities
Nervous Impulses from
the Respiratory Center
 Main respiratory center is the medulla
 Apneustic center assumes respiratory
control if the medulla fails to initiate
impulses
 Pneumotaxic center controls expiration
 Stretch receptors prevent overexpansion
of the lungs
 Hering-Breuer reflex
Chemoreceptors
 Located in carotid bodies, arch of the
aorta, and medulla
 Stimulated by decreased PaO2,
increased PaCO2, and decreased pH
 Cerebrospinal fluid (CSF) pH is
primary control of respiratory center
stimulation
Hypoxic Drive
 Hypoxemia is a profound stimulus
of respiration in a normal individual.
 Hypoxic drive increases respiratory
stimulation in people with chronic
respiratory disease.
Measures of
Respiratory Function
 Respiratory rate
 Factors
influencing rate
include:
 Fever, emotion,
pain, hypoxia,
acidosis, stimulant
drugs, depressant
drugs, sleep
Age
Rate per
Minute
Adult
12–20
Children
18–24
Infants
40–60
Measures of
Respiratory Function
 Respiratory capacities and
measurements
 Total lung capacity
 Total volume of air at maximum inhalation
 Average adult male TLC- 6 liters
 Tidal Volume
 Average volume of gas inhaled
or exhaled in one respiratory cycle
 Approximately 500 cc
Measures of
Respiratory Function
 Respiratory capacities and measurements
 Dead-space
 Amount of gases in tidal volume
that remains in the airway
 Alveolar volume
 The alveolar volume is the amount of gas in the tidal
volume that reaches the alveoli for gas exchange
 Minute volume
 The amount of gas moved in and out of the respiratory
tract in 1 minute
Measures of
Respiratory Function
 Respiratory capacities and
measurements
 Alveolar minute volume
 Amount of gas that reaches the alveoli for gas
exchange in one minute
 Inspiratory reserve volume
 The amount of air that can be maximally inhaled
after a normal inspiration
 Expiratory reserve volume
 The amount of air that can be maximally exhaled
after a normal expiration
Measures of
Respiratory Function
 Respiratory capacities and
measurements
 Residual volume
 The amount of air remaining in the lungs at the end
of maximal expiration
 Functional residual volume
 The volume of gas that remains in the lungs at the
end of normal expiration
 Forced expiratory volume
 The amount of air that can be maximally expired
after maximum inspiration
Non-Invasive
Respiratory Monitoring
 Devices will assist your measurement of
the effectiveness of oxygenation and
ventilation.
 Pulse oximetry, capnography,
esophageal detection, and peak flow
measurements
Non-Invasive
Respiratory Monitoring
 Pulse Oximeter
 Measures
hemoglobin oxygen
saturation in
peripheral tissues
 The “fifth vital sign”
 Normal SpO2 varies
between 95 and 99
percent
 85 percent or lower
indicates severe
hypoxia
© Scott Metcalfe
SPO2 and waveform
 Plethysmograph
 Optically measures bloodflow to an
organ
Non-Invasive
Respiratory Monitoring
 Capnography
 Recordings or displays of exhaled CO2
measurements are called capnography.
 When perfusion decreases, as occurs in
shock or cardiac arrest, ETCO2 levels reflect
pulmonary blood flow and cardiac output,
not ventilation.
Non-Invasive
Respiratory Monitoring
 Capnography
(cont.)
 A normal partial
pressure of end-tidal
CO2 (PETCO2) is
approximately 35-45
mmHg.
 Increased ETCO2
levels are found with
hypoventilation,
respiratory
depression, and
hyperthermia.
 Decreased ETCO2
levels can be found in
shock, cardiac arrest,
pulmonary embolism,
bronchospasm, and
with incomplete
airway obstruction.
Non-Invasive
Respiratory Monitoring
 Capnography
 Colorimetric
Device
 Contains pHsensitive paper
 Causes a color
change in the
paper
Reprinted by permission of Nellcor Puritan Bennett LLC,
Pleasanton, California
 Electronic
Devices
 Use an infrared
technique to detect
CO2
 May be either
qualitative or
quantitative
© Scott Metcalfe
Non-Invasive
Respiratory Monitoring
 Capnography (cont.)
 Clinical application
 Allows continuous
monitoring of airway
placement and
ventilation for
intubated patients
 Monitoring nonintubated patients
 Useful in CPR
• Rise with the onset of
effective CPR
© Scott Metcalfe
Non-Invasive
Respiratory Monitoring
 Esophageal
Detector Device
 May be either a
rigid syringe or a
bulb syringe
© Wolfe Tory Medical
IV Therapy
Catheters
 Sizes 24-14ga
 Varies in
model types
Components
 Iv lock
 Saline
 Heparin
 Iv tubing
 Medication bag
Fluid Administration
 Administer up to 250ml
of saline.
 Medical control option
for 250ml or more
 Indicators
 Excessive bleeding
 Blood pressure below 100mm
HG
 Suspected dehydration
 Suspected internal bleeding
Field Triage
&
Patient Assessment
Priority Determination
 Once the initial assessment is
completed, determine the patient’s
priority.
 If serious injury or illness is indicated by
the initial assessment, conduct rapid
head-to-toe assessment for other
potential life-threats and initiate
transport.
Top Priority Patients
 Poor general
impression
 Unresponsive
 Conscious but
cannot follow
commands
 Difficulty
breathing
 Hypoperfusion
 Complicated
childbirth
 Chest pain and BP
below 100 systolic
 Uncontrolled
bleeding
 Severe pain
 Multiple injuries
Expedite transport for a high-priority
patient and continue assessment and
care en route.
© Glen Jackson
The Focused History
and Physical Exam
Types of Patients
 Trauma patient with significant
mechanism of injury
 Trauma patient with isolated injury
 Responsive medical patient
 Unresponsive medical patient
The Major Trauma
Patient
 Sustained significant injury
 Exhibits altered mental status from the
incident
Evaluate the trauma scene to determine
the mechanism of injury.
© Robert J. Bennett
Predictors of Serious
Internal Injury
 Ejection from
vehicle
 Death in same
passenger
compartment
 Fall from higher
than 20 feet
 Rollover of
vehicle
 High-speed motor
vehicle collision
 Vehicle-passenger
collision
 Motorcycle crash
 Penetration of the
head, chest, or
abdomen
MOI Considerations for
Infants and Children
 Fall from higher than ten feet
 Bicycle collision
 Medium-speed vehicle collision
with resulting severe vehicle
deformity
A bent steering wheel indicates
potentially serious injuries.
Courtesy of Edward T. Dickinson, MD
Rapid Trauma Assessment
 Not a detailed physical exam
 Fast, systematic assessment for
other life-threatening injuries
 Findings may influence transport
decision
DCAP-BTLS
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Deformity
Contusion
Abrasion
Penetration
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Burns
Tenderness
Lacerations
Swelling
Deformity
Contusion
Abrasions
Penetrations
Burns
 Superficial:
 Partial thickness:
 Full thickness:
Tenderness
Laceration
Swelling
Hemorrhage
&
Tourniquets
Hemorrhage Assessment
 Scene Size-up
 Standard
precautions are
essential
 Evaluate the
mechanism of
injury
 Time elapsed since
injury
 Determine the
amount and rate of
blood loss
© Jeff Forster
Hemorrhage Assessment
 Primary Assessment
 General Impression
 Obvious Bleeding
 Mental Status
 ABC
 Interventions
 Manage as you go
•
•
•
•
O2
Bleeding control
Shock
BLS before ALS!
Hemorrhage Assessment
 Secondary Assessment
 Rapid Trauma Assessment
 Full head to toe
 Consider air medical if stage 2+ blood loss
 Focused Physical Exam
 Guided by c/c
 Vitals, SAMPLE, and OPQRST
 Additional Assessment
 Search for signs of internal bleeding
• Bleeding from body orifice, melena, hematochezia
 Orthostatic hypotension
Hemorrhage Assessment
 Ongoing Assessment
 Reassess vitals and mental status:
 Q 5 min: UNSTABLE patients
 Q 15 min: STABLE patients
 Reassess interventions:




Oxygen
ET
IV
Medication actions
 Trending: improvement vs. deterioration
 Pulse oximetry
 End-tidal CO2 levels
Hemorrhage Management
 Assure that the airway is patent
and breathing is adequate.
 Maintain the airway and provide the necessary
ventilatory support.
 Administer high-flow oxygen.
 Carotid pulse.
 CaAssure that the patient has a palpable re
for serious (arterial and heavy venous)
hemorrhage, immediately after you correct
airway and breathing problems.
Hemorrhage Management
 Direct Pressure
 Controls all but the
most persistent
hemorrhage
 If bleeding saturates
the dressing, cover it
with another dressing
 If ineffective, may
be necessary to
visualize wound to
apply pressure
directly to site
Hemorrhage Management
 Tourniquet
 Consider using a tourniquet only as a last
resort when hemorrhage is prolonged and
persistent.
 Apply a blood pressure cuff just proximal to
the hemorrhage site.
 Inflate to apply pressure 20-30mmHg greater than
the systolic blood pressure
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