TBI - 8 (2 SATA) Flashcards
Physiologic Review of the neurological system
- Central Nervous System and Peripheral Nervous System
- Brain
- Brainstem – reflexes, vital signs
- midbrain, pons, medulla oblongata
- Cerebellum – muscle movement, balance, control
- Cerebrum – Largest part, 2 hemispheres, 4 lobes
- Frontal lobe
- Parietal lobe
- Temporal lobe
- Occipital lobe
Pearson (2nd Ed.) Nursing: A Concept-based Approach to Learning, p.688-699
Physiologic Review (cont.) Protective structures of the brain
- Skull – bony protection to the brain that does not allow swelling
- Meninges – protective connective tissue made out of three membranes
- Cerebrospinal fluid – clear fluid in the subarachnoid space
- cushions the brain
- maintains chemical balance
Intracranial Pressure (ICP)
- ICP is the pressure inside the skull
- For adults >20 warrants immediate treatment intervention
- Maintained via balance of blood volume, brain tissue, and CSF
- More clearly described in Monroe Kellie Doctrine
Monroe Kellie doctrine
- The body attempts to maintain equilibrium when ICP increases
- Decrease blood supply to brain to compensate
- Leads to a decrease in tissue perfusion of brain
-bleed/tumor/seizure/liver failure
Physiological importance of traumatic brain injury (tbi)
- Brain is in a “closed system” within the skull
- Impacts to the head can cause the brain to impact against the skull (coup and countercoup)
- Bleeding within the skull can cause a feedback loop where increases in pressure reduces blood flow to the brain
- Swelling to brain or surrounding tissues may also cause the feedback loop reducing blood flow to the brain.
[coup - injury on same side of impact
countercoup - injury on opposite side of impact]
How do we monitor ICP?
- Invasive pressure transducer placed in the ventricles, subarachnoid space, epidural space
- Several varieties – best is the ventriculostomy
- Some noninvasive options but not suitable for long term monitoring and are generally not accurate
infection risk - meningitis
brain / vessel injury
bleeding
Measuring ICP
Ventriculostomy
- Measured via the CSF in the ventricles of the brain
- Normal is 5-15mmHg in adults
- Above 20mmHg requires immediate intervention
•ANYTHING OVER 30mmHg IS LIFE THREATENING
hydrocephalus - fluid on brain
spine - not as accurate reading as brain
Measuring Cerebral Blood Flow
•Start with MAP – Mean Arterial Pressure [average pressure in arteries throughout cardiac cycle]
•Equation: MAP = [(2 x diastolic)+systolic] / 3
Diastole counts twice as much as systole because 2/3 of the cardiac cycle is spent in diastole.
A MAP of about 60 is necessary to perfuse coronary arteries, brain, kidneys.
•Usual range: 70-110
•Practice
120/80 = MAP __93____
100/54 = MAP __69____
142/96 = MAP __111____
Cerebral Perfusion Pressure (CPP)
- CPP – pressure needed to ensure blood flow to brain
- CPP = MAP – ICP
- Normal CPP is between 60-100mmHg
- <50mmHg is deadly
CPP ↑ 70 = greater outcome
Ventriculostomy Nursing Care
- Keep transducer set at “0” unless otherwise ordered, keep level with patient’s head
- Avoid anything that might impair drainage
- Monitor insertion site
- Transducer and drainage system are external
- Mean pressure measured at end of expiration
foramen magnum
- do not get out of bed
- do not reposition in bed
~125-150ml spinal fluid in body
~20ml/hr produced
Clinical Manifestations of ↑ ICP
- Δ in LOC [anxiety, restlessness, lethargy, repeating questions]
- Cushing’s Triad
- Ocular signs (papilledema / pupillary response changes / impaired eye movement)
- ↓ motor function or posturing
- Headache
- Vomiting
- Changes in speech
- Seizures
- Hemiparesis
Infants •Bulging fontanels •Cranial suture separation •↑ head circumference •high pitched cry •Projectile vomiting / reflux
Glascow Coma Scale
Eye Opening Response:
• 4 → Eyes open spontaneously 4 points
• 3 → Eyes open to verbal command, speech, or shout
• 2 → Eyes open to pain (not applied to face)
• 1 → No eye opening
Verbal Response:
• 5 → Oriented
• 4 → Confused conversation, but able to answer questions
• 3 → Inappropriate responses, words discernible
• 2 → Incomprehensible sounds or speech
• 1 → No verbal response
Motor Response:
• 6 → Obeys commands for movement
• 5 → Purposeful movement to painful stimulus
• 4 → Withdraws from pain
• 3 → Abnormal (spastic) flexion, decorticate posture →│←
• 2 → Extensor (rigid) response, decerebrate posture ←│→
• 1 → No motor response
Minor: 13-15
Major: 9-12
Severe: 3-8
3-rain dead
8-call Organ Procurement - req’d by law
12-intubate - protect airway
7-coma
Pulse Pressure
- Pulse Pressure – measures expansion of arteries in response to the volume of blood ejected during systole
- PP=SBP-DBP
- BP of 120/80 then PP=40
Pulse Pressure
- Pulse Pressure – measures expansion of arteries in response to the volume of blood ejected during systole
- PP=SBP-DBP
- BP of 120/80 then PP=40
Cushing’s triad
Cushing’s triad is a late sign
- Bradycardia
- Hypertension with widening pulse pressure
- Irregular, shallow respirations
•Monitor for Cushing’s Triad in ALL brain injury pts
Ocular Changes
- Anisocoric – pupil of one eye differs in size from the other
- Papilledema – swelling of optic disc (blanching)
- Pupillary reaction changes Fixed, bilateral, dilated pupils – very bad, poor prognosis, very ominous
Motor Function
- Assess motor movement, function, coordination
- We evaluate each extremity separately if they are able to follow commands
- Response to stimuli
- Decorticate - abnormal flexion (in)
- Decerebrate – abnormal extension (out)
usually not purposeful movement
TBI
Initial Management
- AIRWAY
- If GCS<8 intubate “less than 8, intubate”, or if any question about airway management
- If trauma, immobilize cervical spine
- Pulse ox, vitals, neuro checks, IV
- Check blood glucose (bring back to normal to rule/out)
- CBC, electrolytes, ABGs, LFTs, UA, blood culture if febrile, UDS, ETOH
Diagnostics
- X-Ray – just bone
- CT Scan – brain and soft tissue
- MRI – gives cross section view, like a slice of bread
- Angiogram – identifies ruptured, blocked, etc. blood vessels
- EEG – electroencephalograph – measures electrical activity in brain (life support determination)
Drug Therapy
- Loop diuretics (Mannitol)
- Corticosteroids – primarily dexamethasone
- Barbiturates – pentobarbital
- Phenytoin – anti-convulsant
- Sedatives + analgesics – morphine, fentanyl, Propofol (↓ vasoconstriction)
all given IV - NO PO even if awake
Therapy
Mannitol
- Go to drug for ↑ ICP – reduces cerebral swelling and edema
- Plasma expander – reduces viscosity of blood
- Osmotic diuretic
- Watch for hypotension, renal impairment
- Other hypertonic solutions may be used
•*MAY MAKE INTRACRANIAL HEMORRHAGE
Hyperventilation
•Lowers CO2 → vasoconstriction → lowers cerebral blood flow → lowers ICP
temporary fix
CO2 = 35-45
Nutrition
- After head trauma, ↑ ICP – hyper-metabolism, hyper-catabolism
- Start nutrition within 3 days
- ↑ demand for glucose
- Keep patient hydrated
ketones & acidosis
Positioning
- Keep head midline and in neutral position
- Supine
- Keep head of bed around 30-45 degrees
- Don’t get up without assistance, don’t move in bed without assistance
- SEIZURE PRECAUTIONS
no Q2 turns
TBI
Causes
- 28% Falls
- 20% MVC / MVA
- 19% Struck by or struck against objects
- 11% Violence
•About 75% of TBIs seen in emergency rooms are mild cases
Types of TBI
- Concussion – most common, usually from shaking, impact, whiplash
- Contusion – bruising or bleeding in the brain
- Coup-countercoup – contusion on two sides of brain, one from impact and one from of the brain being pushed opposite direction –think whiplash
- Diffuse Axonal – shaking or strong rotation, head moves faster than brain can keep up and axons tear leading to brain cell death
- Penetration – bullet, knife, etc
TBI Level
Mild
- No or very brief loss of consciousness
- Tests/brain scans appear normal
- Usually person is dazed/confused, few if any other symptoms
- Glasgow Coma Scale = 13-15
concussion
Concussions
- Sudden transient head injury with disruption of neural activity and change in LOC
- Grades 1-3 mild to worse
- Sometimes referred to as a “mild TBI”
•OK to let them sleep, as long as there are no urgent assessment findings e.g. fixed, dilated pupils. Sleep is actually very helpful
Concussions
- Try to limit mental and physical exertion
- May have trouble falling asleep
- Visual (photosensitivity especially), hearing, balance, memory issues
- Headache•Vomiting
Concussions
- Try to limit mental and physical exertion
- May have trouble falling asleep
- Visual (photosensitivity especially), hearing, balance, memory issues
- Headache
- Vomiting
TBI Level
Moderate
- Loss of consciousness from minutes to hours
- Confusion for days to weeks
- Physical, cognitive, and/or behavioral changes that may be temporary or permanent
- Glasgow Coma Scale = 9-12
prognosis depends on where injury is
TBI Level
Severe
- Most life threatening and usually intractable
- Injury causes damage to brain tissue
- Extensive rehab which may be partially or completely ineffective
Contusions
- Epidural hematoma
- Slow if venous, fast if arterial
- Unconscious, ↓LOC, headache, N+V
- Emergency surgery
- Subdural hematoma
- Typically venous blood
- Ipsilateral pupils dilate / fixed, drowsy
- Subarachnoid hematoma
- Bleeding into CSF
- Trauma, cocaine abuse, aneurysm ruptures
- Sudden severe headache, stiff neck, decreased LOC
Skull Fractures
- Basilar skull fracture – break in bone at the base of the skull
- Most serious
- Battle’s Sign – ecchymosis behind ears
- Bruising around eyes “Raccoon eyes”
- leaking CSF from nose / ears – Halo sign
- High risk for meningitis but prophylaxis is rarely effective
- Monitor for signs of infection
Skull Fractures
- Linear – most common
- break in bone, but bone doesn’t move
- no interventions if neurological assessments are fine
- Depressed Skull fracture
- part of skull is sunken in
- surgical intervention to correct deformity
Endocrine Problems
•Large number of TBI patients experience endocrine complications
- Diabetes Insipidus
- SIADH
- Hypopituitarism
- Cerebral Salt Wasting – rare, low blood Na concentration, dehydration
fluid/electrolyte issues
Diabetes Insipidus
- Kidneys unable to conserve water – inefficient ADH/Vasopressin
- Polyuria
- Dehydration, ↑ Na
electrolyte monitoring Q2
SIADH
- Too much ADH
- Fluid retention, ↓Na
- Edema, swelling
fluid overload hypersecreted ADH wet lung sounds pulmonary edema cardia loop diuretics preferred - osmotic
leads to pulmonary issues
looks like CHF
Cerebrum
composed of gray matter and has two hemispheres that are divided into four regions knows as lobes
Cerebellum
second largest part of the brain
The cerebellum is made up of gray and white matter and is responsible for muscle movement, balance, and control.
coordinates stimuli from the cerebral cortex, transmitting information required for skeletal muscle coordination and smooth movements
Midbrain
The midbrain or mesencephalon (from the Greek mesos, middle, and enkephalos, brain) is a portion of the central nervous system associated with vision, hearing, motor control, sleep/wake, arousal (alertness), and temperature regulation.
also called mesencephalon, region of the developing vertebrate brain that is composed of the tectum and tegmentum. It is located within the brainstem and between the two other developmental regions of the brain, the forebrain and the hindbrain; compared with those regions, the midbrain is relatively small.
Brain Stem
made up of the midbrain, pons, and medulla oblongata.
The brainstem controls reflexes and influences all basic physiological functions including breathing, blood pressure, and heart rate. The brainstem also regulates activities such as vomiting, hiccupping, coughing, and sneezing. Ten of the 12 pairs of cranial nerves originate in the brainstem.
Parietal Lobe
processes all of the sensory informa-
tion, including shapes, temperature, pain, and two-point dis-
crimination (e.g., hot vs. cold).
Parietal Lobe
processes all of the sensory information, including shapes, temperature, pain, and two-point discrimination (e.g., hot vs. cold)
Occipital Lobe
where the visual cortex is located, processes vision
Occipital Lobe
where the visual cortex is located, processes vision
–
Chase’s condition has improved and he is in the step-down neuro unit. Chase had a trach for his respiratory support while in ICU. He now has a covered and healing stoma. His PICC is in his left forearm. His Foley is to drainage, with hopes to begin bladder training this week. He is receiving tube feedings at 50mL/hr. in his JPEG. Feeds are tolerated well. Chase is awake and responds to his name. He is able to follow minor commands (squeeze my hand) and tracks visitors with his eyes. His plan includes a transfer to rehab this week and his parents are very involved in the discharge plans.
24. What are some conditions that Chase is at risk for developing? List quality interventions to prevent them.
–
Chase’s condition has improved and he is in the step-down neuro unit. Chase had a trach for his respiratory support while in ICU. He now has a covered and healing stoma. His PICC is in his left forearm. His Foley is to drainage, with hopes to begin bladder training this week. He is receiving tube feedings at 50mL/hr. in his JPEG. Feeds are tolerated well. Chase is awake and responds to his name. He is able to follow minor commands (squeeze my hand) and tracks visitors with his eyes. His plan includes a transfer to rehab this week and his parents are very involved in the discharge plans.
25.
What are the
important supports needed for Chase and his family upon transfer?
–
Chase’s condition has improved and he is in the step-down neuro unit. Chase had a trach for his respiratory support while in ICU. He now has a covered and healing stoma. His PICC is in his left forearm. His Foley is to drainage, with hopes to begin bladder training this week. He is receiving tube feedings at 50mL/hr. in his JPEG. Feeds are tolerated well. Chase is awake and responds to his name. He is able to follow minor commands (squeeze my hand) and tracks visitors with his eyes. His plan includes a transfer to rehab this week and his parents are very involved in the discharge plans.
26. What is the current nursing diagnosis / goals (list 3) / interventions for Chase and his family?
–
Chase’s condition has improved and he is in the step-down neuro unit. Chase had a trach for his respiratory support while in ICU. He now has a covered and healing stoma. His PICC is in his left forearm. His Foley is to drainage, with hopes to begin bladder training this week. He is receiving tube feedings at 50mL/hr. in his JPEG. Feeds are tolerated well. Chase is awake and responds to his name. He is able to follow minor commands (squeeze my hand) and tracks visitors with his eyes. His plan includes a transfer to rehab this week and his parents are very involved in the discharge plans.
27.
How do you know that
these
interventions are meeting Chase’s and his family’s needs?
Decorticate
abnormal flexion (in)
Decerebrate – abnormal extension (out)
abnormal extension (out)
ipsalateral
same side
contralateral
opposite side
