Head Injuries Flashcards
What medications can impair consciousness?
Opioids, barbiturates (belladonna, phenobarbital, pentobarbital), benzodiazepines (lorazepam, diazepam, clonazepam, temazepam), medical marijuana (unintentionally)
What is consdered to be an elevated ICP?
ICP >20mm Hg is considered elevated
The brain can maintain a steady CPP when the arterial SBP is? And when ICP is?
CPP – brain can maintain a steady perfusion pressure when the arterial SBP is 50-150mmHg and the ICP is less than 20mmHg
What is the time of onsent of Diabetes Insipidus (DI) as a complication of a TBI? How do we treat it?
Time of onset is typically 5-10 days following initial injury
Tx – aggressive replacement of intravascular volume with intravenous fluids and administration of systhetic ADH (vasopressin or DDAVP)
Usually transient, lasting few days to weeks
Sings of increased ICP? (MIND CRUSHED)
Mental status changes
Irregular breathing
Nerve changes (oculomotor and optic)
Decerebrate and decorticate posturing
Cushing’s Triad
Reflex (positive Babinski)
Unconsciousness
Seizures
Headache
Emesis
Deterioration of motor function
What are the 3 symptoms of cushings traid?
Set of three clinical manifestations:
1) Bradycardia
2) Bradypnea
3) Widening pulse pressure
Intra-proceudre nursing care with sedation? (Common meds used?, how often are vitals taken? WHo might be in the OR?
-Common medications: ketamine (especially kids, but becoming more prevalent in adults), propofol, midazolam, fentanyl/other opioid, nitrous oxide. Often these must be administered by MD or NP, and are usually IV (Ketamine can be IM)
-Vitals taken frequently (e.g. q5min). Usually on cardiac monitor
-RT may be at bedside to monitor airway/breathing. Oxygen applied, often high flow (but depends how sedated the patient is). May use capnography to monitor breathing (measures end-tidal CO2)
-May require two physicians (one to administer medications, one to complete the procedure)
What are some common causes of Impaired LOC? (AEIOU + TIPPS)
Alcohol Trauma
Epilepsy Infection
Insulin Psychological
Opiates Poisons
Urates Shock
Early sings of changes in ICP?
Early = * change in LOC* (any sudden change in the patient’s condition – restlessness, confusion, increased drowsiness has neuro significance); headache, emesis, decrease in Glasgow Coma Scale Score; irritability, pupil dysfunction, cranial nerve dysfunction, seizures; Increased BP, respiratory irregularities, slowing bounding pulse
What is one of the ealiest and most sensitive indicators of a neurological problem? How do we asses it?
Changes in a patient’s LOC is one of the earliest and most sensitive indicators of a neurological problem
-GCS is a widely used, standardized assessment of a patient’s LOC
What are some not so common or “other” causes of impared LOC? (Outside of AEIOU + TIPPS)
hypoglycemia, respiratory failure (decreased oxygen), cardiac failure (decreased cardiac output)
How do we prevent furth injury of a head injury?
Prevention: medical and nursing interventions aim to stop this process in varying ways (slide to come)
What is ICP?
ICP is the pressure inside the skull (brain tissue & CSF)
How does an increase in temp cause an increase in ICP? What are some mehtods we can use to lower body temp?
Disruption of temp-regulating system in hypothalamus can manifest itself as either hypothermia or pyrexia
CNS fevers can be very high
increased temp = increased metabolism - increased metabolism increases CO2 (potent vasodilator)
-may not respond to Tylenol/other antipyretics—remember other methods such as ice packs, removing layers
Risk factors for a TBI in the young (children) population?
young: poor strength and balance, age/stage of growth and development
What arer the two components of consciousness?
1.) Alertness – concerned with individual’s ability to respond to environmental stimuli (GCS)
2.) Awareness: center’s on pt’s orientation to time, person, and place - Awareness is a higher level of functioning than alertness
What does an altered LOC refer to?
Altered LOC can be defined as either a reduction in alertness or an alteration in awareness or both (McLeod) - An ‘altered level of consciousness’ refers to a reduction of one–or both–of these components (Alterness and/or awareness)
What is a TBI?
A broad classification that includes injury to the scalp, skull, or brain
WHat needs to remain the same so that ICP can remain constant?
As long as total volume remains the same, ICP remains constant
Interventions for increased ICP?
Position (30-45 degrees HOB, neutral neck and hips)
Respiratory (prevent hypoxia and hypercapnia) – blood gases, SpO2, suction only as needed, hyperventilation for PaCO2 30-35mmHg
Elevated temperature prevention (monitor, antipyretics, remove blankets, cool room, cool cloths—but prevent shivering)
Systems to monitor (GCS, neuro assessment, drain)
Straining activities to avoid: vomiting, coughing, sneezing, Valsalva, agitation, restraints
Unconscious patient care (skin, lungs, nutrition, oral care, bowels, eye care, DVT prophylaxis, ROM)
Rx: sedatives, vasopressors, antihypertensives, anticonvulsants
Edema management (Mannitol, fluid restrictions, corticosteroids, other diuretics)
Risk factors for a TBI in the young adults population?
–young adults (experimenting with alcohol and drugs, risky behavior, sports, military service)
What is a secondary head injury? What are some examples?
Secondary injury: damage evolves after the initial insult (seen in cascade on slide)
Caused by cerebral edema, ischemia, or chemical changes (lactic acid from anaerobic metabolism as well as buildup of CO2) associated with the trauma
Symptoms of a major concussion?
Prolonged headaches, loss of consciousness > 5 minutes, persistent memory issues, personality changes
What is SIADH as a complicaiton of a TBI? What does it result in?
Syndrome of inappropriate antidiuretic hormone (SIADH)
SIADH – increases total body water because excess ADH secretion results in retention of water
Results in production of small amounts of concentrated urine.
Results in cellular swelling, systematically and intracerebrally
Cerebral swelling increases intracranial pressure and leads to secondary injury
Blood flow to the brain is affect by?
Blood flow to brain is affected by: cardiac output, systemic BP, and blood viscosity
What education do we provide to patients about returning back to activities that have just suffered a concussion?
No sports until all symptoms are gone for at least 24 hours – then a gradual return to play, increase activity slightly each day – if return of symptoms, start again with rest until symptoms gone, then begin gradual return to play
What is a primary head injury? What are som examples?
Primary injury: result of the initial damage
Contusions, lacerations, damage to blood vessels, acceleration or deceleration injury, or foreign object penetration
Risk factors for a TBI in males?
gender (male, risky behavior/aggressiveness)
What is CPP? (Cerebral Perfusion Pressure),What is the normal range?
CPP = MAP – ICP, aka the pressure needed to ensure adequate brain tissue perfusion. Normally 70-100mmHg
What is the most important component of a neurological assessment? (particulary in high acuity patients?)
Assessing consciousness is one of the most important component of a neurological assessment, particularly in high acuity patients
What is the normal range for ICP? When does it become negative?
ICP is usually 0-15 mmHg in supine adults (slightly lower in children); becomes negative (averaging −10mmHg) in the vertical position.
How does increased ICP lead to bradycardia?What stage of ICP is it present in?
As ICP continues to increase, leads to bradycardia
·
Bradycardia – present in compensatory phase of an increased ICP (caused by mid-brain compression)
Medulla and vagus nerve provide parasympathetic control of the heart
When stimulated, this lower brain-stem system produces bradycardia
Symptoms of a scalp wound?
Scalp wounds - Tend to bleed heavily; scalp wounds are also portals for infection; **potential for hypovolemic shock in infants/very small children
What are the ealiest signs of DI as a complication of a TBI?
Earliest signs include large amounts of pale, water-like urine and hypotension
How do we treat Syndrome of inappropriate antidiuretic hormone (SIADH) as a complication of a TBI?
Treatment involves restricting fluid intake, possibly diuretics
What is the NS aspect of the neuro assesment? Why? How rapidly can canges occur?
LOC is most NS aspect of neuro assessment as it is the earliest and most sensitive indicator of neurological deterioration (McLeod)
Changes can occur very rapidly (over a few mins or hours) or more slowly (over days/weeks/months)
How do we manage incresed ICP?
Need to maintain CPP! Remember CPP = MAP – ICP
Decrease cerebral volume = surgical evacuation of mass/lesion/hematoma; fluid restriction; diuretics
Decrease CSF volume = ventriculostomy to drain CSF; +/- lumbar drain
Decrease cerebral pressure – positioning, corticosteroids, blood volume = maintain head midline with HOB 30°’ maintain normocarbia {is a state of normal arterial carbon dioxide pressure}; stool softeners (prevent straining) , prevent seizures
Decrease metabolic rate = normothermia {37°C}; sedation and analgesia; seizure management and prophylaxis; decrease cellular metabolic demands
Chanegs in which vitals are considered to be late findings of a TBI?
Changes in T, HR, and BP are considered LATE findings in neuro deterioration
What is the minimum CPP needed for adequate oxygenation delivery to the brain? What level is Ischmeia?what level is impending death?
Minimal CPP of 50-60 for adequate oxygen delivery to brain tissue (<50=ischemia, <30=impending death)
If blood flow to brain interrupted – cellular death happens in five mins
How is compensation accomplished for ICP?
Because brain tissue has limited space to change (cranium/skull is rigid), compensation typically is accomplished by displacing or shifting CSF, increasing the absorption of CSF, or decreasing cerebral blood volume
What can a TBI/Head injury be the result of?
A head injury can be the result of trauma such as a blow to the head or penetration of the skull, or it can be from disease/infection, lack of oxygen to the brain or substance abuse.
WHen we are doing a GCS, what do we do/ask?
-observe patient, then speak to patient, then nail bed pressure/sternal rub/trapezius pinch
-ask orientation questions
-ask to squeeze fingers/lift arms/etc, then nail bed pressure
Diagnostic tests we run to diagnose a TBI?
Blood glucose stat. All blood work. CT scan stat. (note that CT may not be used in minor head injuries such as concussion-which we will discuss later; you can expect a stat CT with GCS <13, age >65, suspicion of open or basilar skull fractures, or more than one episode of vomiting, or if their GCS)
What is brain herniation of a TBI?
-Major and serious complication of a TBI
Brain herniation
· Is a catastrophic complication of traumatic brain injury caused by increased ICP
· Requires emergent interventions
What does post - op care look like for those who had surgery for an increase in ICP?
Vitals – monitor for any changes to vitals; treat fever (increases oxygen requirements – cerebral hypoxia); monitor for seizures
Pain – if poorly treated leads to increased oxygen requirements
Nausea – increased ICP concerns if vomiting. Controlled with meds
Drainage – volume, color, watch for infection
Elevate HOB usually 30 degrees (prevent further cerebral edema)
Postoperative cerebral edema peaks between 48 and 60 hours following surgery.
Bone flap may not have been replaced over surgical site; turning patient to the affected side, if the flap has been removed, can cause irreversible damage in the first 72 hours post-op.
Maintain accurate record of intake and output
Prevent pulmonary complications associated with bedrest
Patient and family will need +++ emotional support; honest information
Late signs of changes in ICP?
Late = further decrease in LOC; bulging fontanelle; decreased spontaneous movements; posturing, pupil dilation with decreased or no response to light; further increased BP, irregular respirations; Cushing’s Triad (late, ominous sign) {hypertension, bradycardia, and a widening pulse pressure} impending fatal herniation of the brain.
How does “Procedural Sedation” impair consciousnesss?
Procedural sedation falls midway on the spectrum of complete consciousness (awake alert) to complete unconsciousness (deep coma). Patients are sedated to the point of unawareness (so more than administering lorazepam), but not to the point of no longer protecting their airway (as in general anesthesia). This allows us to complete procedures without as much risk to the airway, but it is a delicate balance to maintain. Common settings for this intervention are the ER and OR, but is possible in other settings (dental clinics, other outpatient clinics, inpatient settings such as cath lab).
Risk factors for a TBI in the elderly population? (>75)
elderly: polypharmacy, comorbidities (e.g. alzheimers, heart conditions), poor strength and balance
What do altered changes in LOC indicate?
Altered LOC may be due to any of the following pathologies:
1. neurologic- a stroke, head injury
2. Toxicologic - toxin exposure (meds, alcohol, illicit drugs), or
3. Metabolic– diabetic ketoacidosis or hepatic or renal failure
What is the incidence of sezuires as a complication in TBIs? What can early onsent seizures do/cause?
- Incidence 22-50% in penetrating injuries
Early onset seizures may increase ICP, hypoxia, and increase metabolic demands increasing the severity of secondary injury
What is the first and second leading cause of TBI’s?
Falls were the leading cause of traumatic head injuries and accounted for 43 per cent of the admissions (950/year)
- Motor vehicle collisions were the second leading cause of head injury admissions and accounted for 20 per cent (139/year)
What is cushings triad?(what is it realted to?)
3 clinical manifestations are related to pressure on the medullary area of brainstem
What should we watch for that can indicate possible brain stem damage?
watch for bradycardia, hypotension, inability to maintain body temperature (possible brain stem damage)
WHat is a concussion?
a temporary, functional neurological impairment resulting from a direct or indirect hit to the head
Post op nursing care after a patient has recived sedation?
-Depending on unit policy, vitals are obtained frequently at first (e.g. q15min x2, then q30min, then q1h, etc), including sedation level/GCS
-Once the patient becomes more aware, they should have their swallowing/gag reflex assessed before offering anything by mouth, and should have their balance/walking assessed before discharge (if applicable)
What do changes in vital signs indicate with a TBI/Head injury?
Vital signs -Changes in vital signs can indicate deterioration in neurologic status
What does consciousness mean? What does it depend on?
State of awareness of oneself and surrounding environment
Depends on effective communication between cerebral cortex and brainstem
Symptoms of a skull fracture?
Skull fractures - Usually have localized, persistent pain
- Fractures of the base of the skull; Bleeding from nose, pharynx, or ears ; battle’s sign: ecchymosis behind the ear; CSF leak—halo sign—ring of fluid around the blood stain from drainage (can also do a glucose test to distinguish from other fluids like nasal secretions—CSF has glucose in it)
How does Diabetes insipidus (DI) become a complication for a TBI? (What is it associated with? How can it result in a TBI? What does it result into, why?)
– Condition associated with improper water balance
- TBI may result in pressure on (or damage to) the pituitary gland and loss of ADH secretion
Loss of ADH secretion results in polyuria
Time of onset is typically 5-10 days following initial injury
What does LOC range from?
LOC ranges from a state of complete alertness and awareness to deep coma
Symptoms of a concussion?
Brief loss of consciousness, retrograde amnesia, headache
What do fixed and dialted pupiles indicate?
Fixed and dilated – overwhelming injury with damage to brain stem – very poor prognosis
What should the nurse do pre-procedure with a patient that is about to recive sedation?
-The physician completing the procedure needs to explain the procedure and must obtain informed consent before any medications are administered, even when the procedure is urgent.
-Ask about allergies (e.g. eggs—no propofol!), possibly airway assessment (e.g. if they snore, if they’ve had sedation before—anticipate risks to airway)
