NR40 Nursing II

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Transcript NR40 Nursing II

NR240
Nursing II
Care of clients with coma & increased
intracranial pressure
Review self study slides 1-6
1
Review Chapt 43 neuro A & P key
terms
 Structure of Neurons
 Mechanism of nerve impulse
conduction
 Neurotransmitters
 Acetylcholine
 Serotonin
 Dopamine
 Norepinephrine
 Structures of the brain
 Supratentorial/infratentorial
 Cerebral circulation
Circle of Willis
 Blood-brain barrier
 Cerebrospinal fluid
circulation
 Spinal cord structures
 Ascending tracts
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Spinothalamic tracts
Spinocerebellar tracts
descending tracts
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Extrapyramidal tracts
Basal ganglia
 Peripheral nervous system
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Sensory receptors
Plexuses
Lower motor neuron
Reflexes
Cranial nerves
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Review Chapt 43 neuro diagnostic
assessment
Emphasize understanding of prep, indications and
outcomes
 Radiographic exam
 Cerebral angiography
 CT scanning
 MRI
 MRA
 EEG
 EMG
 Lumbar puncture
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Review Terms related to Coma
 Obtundation
Reduced alertness
 Lethargy
 Abnormal drowsiness
 Persistent vegetative state
 state results when the cerebrum, which controls thought and
behavior, is destroyed, but the thalamus and brain stem,
which control sleep cycles, body temperature, breathing, and
heart rate, are spared
 Locked- in state
 people are conscious and able to think but are so severely
paralyzed that they can communicate only by opening and
closing the eyes in response to questions
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Review Terms related to Coma
 Delirium
 state of acute confusion, inattention, and altered level
of consciousness (LOC), usually abrupt in onset (over
several hours to several days).
 Stupor
 is an unresponsive state from which a person can be
aroused only briefly and with vigorous, repeated attempts.
 Coma
 is an unresponsive state from which a person cannot be
aroused, even with vigorous, repeated attempts.
 Brain death
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brain has permanently lost the ability to perform all vital
functions, including maintenance of breathing
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Defining Altered Mental State
 Change in neurological function on a continuum
affecting:
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Arousability
Cognition, verbal response
ability to follow commands
Motor function
Sensory function
Presence of reflexes
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Neurological Assessment
 Level of consciousness (LOC),Mental status
 Cognition, emotional status
 cranial nerves
 reflexes
 motor function
 Cerebellar
 strength
 sensory function
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Eliciting a Focal Neurological Deficit
 A deficit that occurs in any of the areas of
neurological exam
 Does not need to be all-encompassing
 May be focused in one area or a few areas that
are related
 Can manifest in and effect:
 Level of consciousness, motor, sensory, reflexes,
cranial nerve function
 Elicited through comprehensive assessment
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Performing a neurocheck
 Rapid neurocheck:
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Glasgow coma scale (eye opening, motor
response, verbal response)
Pupilary response
Motor strength
Vital signs
Sensation
Seizure activity
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Documenting Neuro status
 Neurological Flowsheet
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Key points
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Must be compared to baseline
Must evaluate right and left separately when
possible
Should be performed with vital signs
Physician notification must be timely
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Reporting criteria based and
neurocheck results
 Drop in GCS of 2 points or more
 Deterioration in neuro status
 Abnormal vitals signs:
 rising systolic with unchanged diastolic (widened pulse
pressure), bradycardia and change in respiratory
pattern (Cushings triad)
 Rising body temperature (can increase brain oxygen
demand)
 New onset seizure activity
 CSF leakage
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Acute changes requiring emergency
intervention
Notify MD within 5 minutes of discovering:
 Unilateral pupil dilation,
 Loss of pupil response
 Abnormal flexion or extension
 Loss of brain stem reflexes (gag reflex, corneal
reflex)
 Initiate emergency response
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Ensure airway, provide oxygen, increase frequency of
assessment establish IV access
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Abnormal posturing
 Decorticate
 Decerebrate
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Brain stem reflexes (3 types)
 Caloric stimulation
Cold calorics video (performed by MD)
Injection of 20-30 cc syringe with an 18 gauge angiocath filled
with ice water and squirted into the ear while evaluating eye
movement.
In a Normal response, eyes conjugately deviate away from the
cold ear, then snap back to midline
 Corneal Reflex
Touch the lateral lower corner of the cornea.
In a Normal response, ipsalateral eye blinks
 Cough, gag reflex
Jiggle the endotracheal tube or NG tube to stimulate the larynx or
pharynx
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In a Normal response, patient coughs or gags
PC: neurologic dysfunction (AMS/Coma)
Change in mental status
new onset focal neurological deficit
Perform a comprehensive assessment (see next slide)
Evaluate possible cause or contributing problem (see etiology)
Monitor results of rule out lab/diagnostics (see workup)
Treat the underlying cause
Provide supportive care until reversed
NIC: hemodynamic monitoring
NIC: Neurological monitoring
Report acute declines in LOC, pupillary changes, abnormal posturing,
abnormal brainstem reflexes and initiate
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NIC: shock management
Perform comprehensive Assessment
 Determine if the individual has a history of
altered mental states
 Assess the current signs and symptoms of
AMS
 Determine if the patient is at high risk for
developing AMS
 focus on correctly identifying the causes of
AMS
 Define the duration and course of symptoms
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Evaluate possible cause of AMS
 Determine if conditions or situations that may
affect mental status are present:
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Medications/non-compliance with regimen
Fluid or electrolyte imbalance
Infections
Hypo- or hyperglycemia
Recent hospitalization
Recent surgery under general anesthesia
Recent change in living situation or
environment
Recent fall or other trauma
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Evaluate possible cause of AMS
(cont’d)
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Significant pain
Alcohol or drug abuse
Hypo- or hyperthyroidism
Nutritional deficiency
Recent stroke or seizure
Primary metastatic brain tumors or other
malignancies
Cardiac arrhythmia/myocardial infarction
 Always review the patient's medications, as
these are a common source of AMS
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Perform Lab/diagnostics to rule out cause
 Electrolytes, BUN, glucose, creatinine, serum osmolality/urine
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sodium (to identify fluid/ electrolyte imbalance)
Urinalysis and/or urine culture (if urinary tract infection is
suspected)
TSH/free T4 (to identify possible thyroid dysfunction)
Complete blood count (CBC) (if infection, inflammatory
processes, bleeding, or anemia are suspected)
Chest x-ray/Oxygen saturation (if pneumonia or pulmonary
embolism are suspected)
EKG/rhythm strip (if a cardiac arrhythmia or other heart
dysfunction is suspected)
Albumin (if undernutrition is suspected)
Serum drug levels, when appropriate
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Perform Lab/diagnostics to rule out cause
 Radiological examination
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CT
MRI
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Nursing Priorities for the unconscious
client (source: Carpenito)
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PC: Respiratory insufficiency
PC: Pneumonia/Atelectasis
PC: Increased intracranial pressure
PC: Seizures
PC: Sepsis
PC: Thrombophlebitis
PC: Fluid/electrolyte imbalance
PC: Negative nitrogen balance
PC: Bladder distention
PC: Stress ulcers
PC: Renal calculi
PC: Urinary tract infection
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Nursing Priorities for the unconscious
client (source: Carpenito) cont’d
 Nursing Diagnoses
 Infection, Risk for related to immobility and invasive devices
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(tracheostomy, Foley catheter, venous lines)•
Risk for Tissue Integrity, Impaired: Corneal related to corneal
drying secondary to open eyes and lower tear production
Family Anxiety/Fear related to present state of individual and
uncertain prognosis•
Risk for Oral Mucous Membrane, Impaired related to inability to
perform own mouth care and pooling of secretions•
Total Incontinence related to unconscious state
Disuse Syndrome
Powerlessness (family) related to feelings of loss of control and
restrictions on lifestyle
Risk for Ineffective Airway Clearance related to stasis of
secretions secondary to inadequate cough and decreased
mobility
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Understanding ICP
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Mean Arterial Pressure
 Calculation of systolic and diastolic blood
pressure that indicates the degree of tissue
perfusion to vital organs
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Equation:
Mean Arterial Pressure ~= 1/3 * SBP + 2/3 * DBP
Usual range: 70-110
 Should exceed 70 to ensure cerebral tissue
perfusion
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Cerebral perfusion pressure (CPP)
 Cerebral perfusion pressure (CPP) is a
measure of adequate supply of blood to
cerebral tissue.
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CCP=MAP - ICP
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cerebral blood flow (CBF)
 cerebral blood flow (CBF) is ensured through
regulation of arterial blood supply and
cerebrovascular resistance (CVR)
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CBF=CPP ÷ CVR.
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Determinants of supply occur as a result of:
 Vasomotor control of cerebral arteries
 Influenced by circulating levels of carbon dioxide,
oxygen, products of metabolism, and pH.
 Autoregulatory response to changes in MAP
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Factors contributing to Cerebral arterial
vasodilation to preserve Cerebral blood flow
Contributing Factors
Increased PaCo2
Decreased PaO2 < 50
pH<7.35
Decreased blood pressure
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Factors contributing to Cerebral arterial
vasoconstriction to preserve Cerebral blood flow
Contributing Factors
decreased PaCo2 < 35
pH>7.45
decreased body temperature
Increased blood pressure
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Maladaptation in Autoregulation
 Decreased systolic BP results in decreased
CPP
 Decreased CPP leads to increased
vasodilation
 Increased vasodilation increased cerebral
blood volume
 Increased cerebral blood volume increases
ICP which in turn decreases cerebral
perfusion pressure and the cycle repeats
itself
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Defining Intracranial Pressure
 measure of pressure inside the cranium
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has an arbitrary numeric amount
 Can be monitored using pressure devices
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Intracranial pressure monitoring
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Causes of an increased ICP
 Conditions Increasing Brain Volume
 intracranial mass (tumor, hematoma, aneurysm, AVM)
 cerebral edema
 CNS infection (abscess, inflammatory process)
 Conditions Increasing Blood Volume
 obstruction of venous outflow
 hyperemia
 hypercapnea
 Conditions Increasing CSF Volume
 increased production
 decreased reabsorption of CSF (meningitis, SAH)
 obstruction to flow of CSF
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High Risk Populations for Increased
ICP
 Intracerebral masses
 blood clots
 blockage of venous outflow
 head injuries
 inflammatory diseases
 cranial surgery
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Physiology of Intracranial Pressure
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The cranium is a fixed box containing brain
tissue, blood and CSF that can not readily
accommodate increasing volumes because it
can not expand.
It has similar properties to a suitcase; its size
is fixed and it contains an assortment of
necessary things but there is a limit as to
what you can put in it.
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Physiology of Intracranial Pressure
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When the volume inside the cranium is subject
to stressors that can increase it precipitously, it
results in an increase in intracranial pressure.
Such events include;
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Cerebral vasodilation and edema, decreased
venous return, masses and lesions
It is like an
overstuffed suitcase
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Physiology of Intracranial Pressure
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Intracranial pressure must be
normalized to ensure adequate
function of the Central Nervous
system
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Normal ICP is 10-15 mm Hg
 This is accomplished by shunting CSF(
to lumbar subarachnoid space),
returning venous blood to the heart,
and, if necessary, shifting away from
the site of edema inside the skull.
It would be like packing the
extra stuff into a second
suitcase
SHUNTING
SHUNTING
SHUNTING
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Relationship of volume to pressure
Monroe-Kellie Hypothesis
to maintain a normal ICP,
a change in the volume of one compartment must be offset by a reciprocal change
in the volume of another compartment
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When you have too much in your
suitcase, you have to unpack some of it
Your brain needs to do
the same thing when the
ICP is too high.
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Physiology of Intracranial Pressure
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If the stressors that increase volume are too
great inside the cranium it becomes difficult to
get anything else in such as;
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Oxygenated blood and nutrients, exacerbating
cerebral edema and intracranial pressure
The only way you could
get anything else in is
by force
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Physiology of Intracranial Pressure
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Mean arterial pressure will reflexively rise to
overcome a rising intracranial pressure to
restore perfusion
There is only just
much force that can
be applied
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Physiology of Intracranial Pressure
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If the pressure elevated too markedly, the
brain tissue will displace through the foramen
occipitalis.
This is referred to as brain herniation
The suitcase will
open and its content
will spill over
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Brain Herniation
Profound Neurological dysfunction
 Progressive loss of consciousness
 Coma
 Irregular breathing
 Respiratory arrest (no breathing)
 Irregular pulse
 Cardiac arrest (no pulse)
 Loss of all brainstem reflexes (blink, gag, pupillary
reaction to light)
 Source Medline plus
 Determining brain death
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Management of increased ICP
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Identification of clients at risk
Initiation of ICP monitoring if indicated
Airway maintenance and ventilation
Oxygenation and low normal PaCO2
Fluid balance to maintain cerebral perfusion
Avoiding positions that increase ICP
Sedation and decreased external stimulation
Osmotic and loop diuretics
Temperature maintenance
Blood glucose control
Pain management and stool softeners
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See ICP sheet
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Definition of ICP monitoring
 type of device that is calibrated to detect the
internal pressure readings
 Interpretation of the readings assist in guiding
actions to restore cerebral tissue perfusion.
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Types
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Ventriculostomy
Subarachnoid
Epidural
Subdural
Parenchymal
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Types of Intracranial Pressure
Monitoring Devices see page 1059
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Indications for ICP monitoring
 Head injury
 Craniotomy
 Intracranial hemorrhage
 Cerebral edema
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Goal if ICP monitoring
 CFS clear
 ICP< 20
 CPP between 60-75
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Strategies to maintain normal ICP
Source: UNC Policy and
Procedure
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Actions to avoid that can increase ICP
Source: UNC Policy and Procedure
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Collaborative care
 PC: CNS infection
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For all types of devices
 PC: brain herniation
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For devices that communicate with CSF and
become obstructed
 PC: decompression hemorrhage
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For devices that communicate with CSF and
rapidly empty ventricle
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PC: CNS infection
Are s/s of acute CNS infection
(meningeal irritation) present?
Nuchal rigidity, photophobia, headache
Assess for s/s of meningeal irritation q 4 hrs and prn
Mon VS and temp as per ICU protocol
Inspect insertion site for drainage, purulence, CSF leak
Inspect CSF for clarity every 4 hours
If present, obtain CSF culture and sent to lab
Initiate antibiotics as prescribed
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PC: brain herniation
Are s/s brain herniation present?
Pupillary changes, loss of brainstem reflexes,
Change in LOC
Perform neurological assessment as per protocol
Keep system free from kinks to avoid disruption in CSF drainage.
Assess for the presence of obstruction and call MD
If present , initiate emergency interventions to minimize herniation
Administer O2, Intubate, Initiate shock management
Call MD
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PC: decompression hemorrhage
Are s/s of acute decompression hemorrhage
present?
Assess for presence of bleeding in CSF drainage, if present call MD
Assess for proper positioning of device and settings each hour
to avoid accidental CSF drainage
Do not allow system to fall below height of head to avoid accidental drainage
Initiate emergency interventions to treat decompression
Increase frequency of assessment Call MD
Prepare to change equipment
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Summary of Plan for
PC: increased ICP
 Assess for s/s of increased ICP
 Monitor labs/vitals and diagnostics and
collaborate if indicators require treatment
 Perform ICP monitoring if indicated
 Avoid positions, maneuvers, situations that
increase ICP
 Administer agents that restore cerebral
perfusion
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