CN II:Optic: VisionCN III:Oculomotor:
-Motor: most EOM movement, opening of eyelids
-Parasympathetic: pupil constriction, lens shapeCN IV:Trochlear: Down and inward movement of eyeCN V:Trigeminal:
-Motor: muscles of mastication
Sensory: sensation of face and scalp, cornea, mucous membranes of mouth and noseCN VI:Abducens: lateral movement of eyeCN VII:Facial:
-Motor: facial muscles, close eye, labial speech, close mouth
-Sensory: taste (sweet, salty, sour, bitter) on anterior two-thirds of tongue
-Parasympathetic: saliva and tear secretionCN VIII:Acoustic: hearing and equilibriumCN IX:Glossopharyngeal:
-Motor: pharynx (phonation and swallowing)
-Sensory: taste on posterior one-third of tongue, pharynx (gag reflex)
-Parasympathetic: parotid gland, carotid reflexCN X:Vagus:
-Motor: pharynx and larynx (talking and swallowing)
-Sensory: general sensation from carotid body, carotid sinus, pharynx, viscera
-Parasympathetic: carotid reflexCN XI:Spinal: movement of trapezius and sternomastoid musclesCN XII:Hypoglossal: movement of tongueWhat are the three essential components of the skull?Brain tissue, blood, and cerebrospinal fluid (CSF)What is the percentage breakdown of the three components of the brain? (brain tissue, blood, CSF)Brain tissue: 78%
Blood: 12%
CSF: 10%The balance of the three components of the brain (brain tissue, blood, and CSF) maintains an ICP of __-__ mm Hg under normal conditions.5-15An ICP of 10 mm Hg is life-threatening.FALSE; an ICP above 15 mm Hg is life-threatening.What is increased ICP?A life-threatening situation that results from an increase in any or all of the three components of the skull: brain tissue, blood, and CSFWhat are factors that influence ICP?Arterial pressure, venous pressure, intraabdominal and intrathoracic pressure, posture, temperature, and blood gases (CO2 levels)The degree to which factors increase ICP depends on the ability of the brain to:Accommodate to the changesWhat is the normal blood gases pH?7.35-7.45What is the normal blood gases PCO2?35-45 mm HgWhat is the normal blood gases HCO3?21-28 mEq/LWhat is the normal blood gases PO2?80-100 mmHgWhat is the normal blood gases O2 saturation?95% - 100%What is the normal blood gases O2 content?15 - 20 volume %What is the normal blood gases base excess?0 +/- 2 mEq/LWhat is the best bed angle position for a patient with increased ICP?10-30 degreesT or F: Coughing increases ICP.TRUE; coughing increases intrathoracic pressure, therefore increasing ICP.T or F: The Valsalva maneuver increases ICP.TRUE; the Valsalva maneuver increases intraabdominal pressure, therefore increasing ICPWhy are patients with head injuries given stool softeners?To prevent them from straining, as straining increased ICPT or F: A patient with a head injury should be given an enema to prevent straining.FALSE; enemas alone cause increased ICPWhich doctrine describes relatively constant volume within skull structure?The Modified Monro-Kellie DoctrineWhat specifically does the Modified Monro-Kellie Doctrine state?If volume in any one of the components increases within cranial vault and volume from another component is displaced, the total intracranial volume will not changeWhat are some normal compensatory adaptations within the brain structure?Alteration of CSF absorption or production; Displacement of CSF into spinal subarachnoid space; Dispensability of the duraThe ability for the brain to compensate is limited. If volume increase continues, ICP __________.RisesWhere can ICP be measured?Ventricles, Subarachnoid space, Epidural space, and Brain Parenchymal tissueWhat is used to measure ICP?A pressure transdcuerWhat is the normal ICP?5-15 mm HgWhat is Cerebral Blood Flow?The amount of blood in milliliters passing through 100 grams of brain tissue in 1 minuteWhat is the average Cerebral Blood Flow?50mL/minute per 100 grams of brain tissueWhat is Autoregulation of cerebral blood flow?Automatic alteration in diameter of cerebral blood vessels to maintain constant blood flow to brain__________ ensures a consistent CBF to provide the metabolic needs of brain tissue and maintain cerebral perfusion pression.Autoregulation of cerebral blood flowWhat is Cerebral Perfusion Pressure (CPP)?Pressure needed to ensure blood flow to the brainFormula: CPP =MAP - ICPWhat is the normal CPP?70-100 mm HgA CPP of < 50 mm Hg is associated with:Ischemia and neuronal deathWhat is compliance?The expandability of the brainFormula: Compliance =Volume/PressureWhat are the stages of the Intracranial Volume Pressure Curve?Stage 1: High compliance
Stage 2: Compliance decreases, risk for increased ICP
Stage 3: Any small addition in volume causes a great increase in ICP, loss of autoregulation
Stage 4: ICP rises to lethal levelsWhat are some factors that affect Cerebral Blood Flow?CO2, O2, and Hydrogen ion concentrationWhat is Cerebral Edema?Increased accumulation of fluid in the extravascular spaces of brain tissue and an important factor contributing to increased ICPWhat are the three types of cerebral edema?Vasogenic cerebral edema, Cytotoxic cerebral edema, and Interstitial cerebral edemaWhat is the most common type of cerebral edema?Vasogenic cerebral edemaVasogenic cerebral edema occurs mainly in:White matterThis type of edema is associated with changes in the endothelial lining of cerebral capillaries.Vasogenic cerebral edemaVasogenic cerebral edema results in the flow of fluid from the __________ to the __________ space.Intravascular to the extravascular spaceWhere does Cytotoxic Cerebral Edema mainly occur?Gray matterCytotoxic cerebral edema results from local disruption of:Disruption of functional integrity of cell membranesFrom where does cytotoxic cerebral edema develop?Destructive lesions or trauma to brain tissueThis type of cerebral edema is a result of periventricular diffusion of ventricular CSF in a patient with uncontrolled hydrocephalusInterstitial cerebral edemaInterstitial cerebral edema can also be caused by enlargement of the:extracellular space as a result of systemic water excess (hyponatremia)Regardless of the cause, cerebral edema that results in an increase in tissue volume has the potential for __________ ICP.increasedWhat are some causes of increased ICP?Mass lesion, cerebral edema, head injury, brain inflammation, metabolic insultSustained increases in ICP result in brainstem compression and __________ of brain from one compartment to another.HerniationHerniations force the cerebellum and brainstem downward through the __________.Foramen magnumIf compression of the brainstem is unrelieved, __________ may occur.Respiratory arrestWith brain displacement and herniation, __________ and __________ are further increased.Ischemia and edemaManifestations of increased ICP depend on:Cause, location, and rate at which the pressure increase occursT or F: The earlier the increased ICP condition is recognized and treated, the better the prognosis.TRUEWhat is a sensitive and important indicator of the patient's neurologic status?Level of consciousnessThe Glasgow Coma Scale scoring system is based on a scale of __ - __ points.1-15In the Glasgow Coma Scale, a score lower than __ indicates that a coma is present.8What is the Glasgow Coma Scale?A method of assessing a client's neurological condition.Cushing's triad is a clinical manifestation of increased ICP. What is Cushing's triad compiled of?Increased systolic pressure (widening pulse pressure), bradycardia with a full and bounding pulse, and irregular respiratory pattern (often does not appear until ICP has been increased for some time or markedly increased suddenly--head trauma)The effect of increased ICP on the hypothalamus can cause a change in:body temperatureWhat are the symptoms of increased ICP?Increased BP, decreased pulse, and decreased respirations (Cushings Triad)What are the symptoms of shock?Decreased BP, increased pulse, and increased respirationsCompression of the oculomotor nerve (CN III) results in:Dilation of the pupil ipsilateral to the mass, sluggish or no response to light, an inability to move the eye upward, and ptosis of the eyelid
