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Neurosensory: Altered Cerebral Function and Increased intracranial pressure (IICP) Updated Fall 2010 by John Nation, RN, MSN From the notes of Charlene Morris, RN, MSN & Marnie Quick, RN, MSN, CNRN Overview of Today’s Lecture Discuss altered cerebral function – – – Anatomy and physiology Definition of common terms Neurological assessment techniques Increased intracranial pressure – – – – Anatomy and physiology Clinical manifestations Interventions Nursing concerns Have you read Lewis pages 1467- 1481? 25% o ta in 0% A bs N 3. s 2. 75% Yes No Abstain Ye 1. Brain A & P: Brain Anatomy Ventricles of the Brain Flow of CSF: Produced by filtration of the blood by the choroid plexus of each ventricle flows inferiorly through the lateral ventricles, intraventricular foramen, third ventricle, cerebral aqueduct, fourth ventricle and subarachnoid space and to the blood. Altered Cerebral Function: Arousal/cognition (LOC) Patho/assessment Reticular Activating System (RAS) – Reticular Formation - meshwork of gray cell within brainstem extending to the thalamus. – – Controls wakefulness, arousal and alertness. Reticular Activating System- You Tube Cerebral cortex outer layer of gray cell bodies of brain. Controls cognition, thought process. Altered Cerebral Function: What is Consciousness? Consciousness (Merriam- Webster): waking life (as that to which one returns after sleep, trance, or fever) in which one's normal mental powers are present “the ether wore off and the patient regained consciousness” Dynamic state Continuum from awareness of self and environment to unawareness Consciousness to deep coma Coma- prolonged unconsciousness Causes of Changes in LOC Alcohol intoxication Drug intoxication (particularly opiates, narcotics, sedatives, and anti-anxiety or seizure medications) Arrhythmia Brain disorders Central nervous system diseases Lack of oxygen (hypoxia) Abnormal blood sugars (diabetic coma) Electrolyte or mineral imbalance Exposure to heavy metals or hydrocarbons Extreme fatigue or sleep deprivation Ketoacidosis Head trauma Heart failure Hypoglycemia (low blood sugar) Increased carbon dioxide levels (hypercarbia) often seen in emphysema Infection Low blood pressure (hypotension) Metabolic disorders Thyroid or adrenal gland disorders Seizures such as those related to epilepsy Shock Stroke Source: National Institute of Health Causes of Coma: Coma can be caused by: – – – Traumatic brain injuries. Brain injuries that result from traffic collisions or acts of violence are the most common cause of comas. Stroke. Acute loss of blood flow to the brain followed by swelling or no blood flow to a major part of the brainstem can result in a coma. Diabetes. Blood sugar levels that get too high (hyperglycemia) and stay too high or get too low (hypoglycemia) and stay too low can cause coma. Source: Mayo Clinic: http://www.mayoclinic.com/health/coma/DS00724/DSECTION=causes Causes of Coma (Cont’d): – Lack of oxygen. People who have escaped drowning or been resuscitated after a heart attack may not awaken due to lack of blood flow and oxygen to the brain. – Infections. Encephalitis and meningitis are infections that cause inflammation of the brain, spinal cord or the tissues that surround the brain. Severe cases of either encephalitis or meningitis can result in a coma. – Toxins. Exposure to toxins, such as carbon monoxide or drug overdoses, can cause brain damage and coma. Source: Mayo Clinic: http://www.mayoclinic.com/health/coma/DS00724/DSECTION=causes Altered Levels of Consciousness: Definitions of Terms Lethargy - a slight reduction in alertness, less aware of what is happening around them and think more slowly. Obtundation - a moderate reduction in alertness or clouding of consciousness. Stupor - an excessively long or deep sleeplike state. Arousal is brief by vigorous stimulation, such as repeated shaking, loud calling, pinching. Coma - is a state of complete unresponsiveness, cannot be aroused, in a deep coma lacks avoidance of pain. – Some reflexes may be present. Altered Cerebral Function: Assessment of arousal/cognition (LOC) Is the patient alert? – Assess to person/place/time/event (A&O x 4) Respond to verbal stimuli? Respond to painful stimuli? – – Purpose: shows the brain receives the impulse, interprets it, and responds Types of painful stimuli: Trapezius pinch- grasp at least two inches of trapezius muscle. Squeeze and twist. Supraorbital pressure- carefully applied upward pressure on the ridge along the upper portion of the bony orbital structure Pressure on finger nails Sternal rub- not considered appropriate Is the patient unresponsive? A-----V-----P-----U! Trapezius Pinch Injury reported as secondary to sternal rub. Descending Response to pain stimuli Pushes your hand away Pulls away from pain site General movement Flexion Extension No response Decorticate posturing- abnormal flexion Decerebrate posturing- abnormal extension Glasgow Coma Scale A score of 13 to 14 indicates mild deficit. A score between 9 and 12 points to moderate deficit, and a score of 8 or less indicates severe coma. Assessment of Vital Signs Temperature - hypothalamus pressure can lead to alterations in body temperature Cushing’s triad – caused by edema & increased intracranial pressure 1) Increased systolic BP 2) Decreased pulse rate 3) Irregular respirations A 44 y/o male presents to the ED after a motor vehicle accident. When you ask him where he is, he opens his eyes and states “work” before closing his eyes again. He states that his abdomen hurts, and he points to the specific location when you ask. What is his GCS? 23% Fo ur te e n n ir t ee Th el ve 0% Tw 4. 31% n 3. 46% ev e 2. Eleven Twelve Thirteen Fourteen El 1. Lethargy is defined as a deep sleep like state where the patient is aroused only with loud noise or painful stimuli. 100% ls e 0% Fa 2. True False Tr ue 1. Assessment of arousal/cognition - Respiratory Respiratory- changes occur as brainstem is being compressed – – – – – – Yawning & sighing Cheyne-Stokes – crescendo-decrescendo with apnea Central Neurogenic hyperventilation Apneustic breathing – Pauses in inspiration and expiration Cluster breathing – irregular deep to shallow with apnea Ataxic respirations - grossly irregular Respiratory Irregularities Cranial Nerves Assessment of arousal/cognition Pupillary light reflex Sensory: CN 2 - Optic Motor: CN 3 Occulomotor – Note pupil size; darken room; shine light in and note reaction and size Occipital lobe Brain stem Assessment of arousal/cognition Pupillary light reflex PERRLA- “Pupils equal, round, reactive to light and accommodation” Anisocoria: The two pupils are not of equal size. Light-near dissociation, refers to a condition where the light reflex is absent or abnormal but the near response is intact. There is no clinical condition in which the light reflex is present and the near response is absent. Amaurotic: blind eye still has consensual response Assessment Arosual/cognition EOM’S & Brain stem function Eye movement- CN 3,4,6 In Deep COMA- test EOM’s by Oculocephalic reflex Doll’s eyes- Sensory- CN 8; Motor- CN 3,4,6 Good Dolls eyes: eyes move in opposite direction of head movement – intact brain stem at Pons & nerves Bad/negative Dolls eyes: eyes do not move head turned How tested with spinal cord injury? Assessment arousal/cognition Additional Motor Assessment Ability to move, strength, and symmetry – – Coordination – Grips, arm strength, & drift Planter flexion, dorsiflexion, & leg strength Finger to nose, heel up and down shin Planter Reflex- Babinski testing Meningeal signs- Brudzinski, nuchal rigidity Planter Reflex and Babinski testing Babinski's reflex – present when the great toe flexes toward the top of the foot and the other toes fan out after the sole of the foot has been firmly stroked. • Postitive response indicates damage to nerve paths connecting the spinal cord and the brain (corticospinal tract) • Abnormal after the age of 2. Meningeal signs- Brudzinski, nuchal rigidity One of the physically demonstrable symptoms of meningitis is Brudzinski's sign. Severe neck stiffness causes a patient's hips and knees to flex when the neck is flexed. Meningitis signs- Kernig’s sign Kernig's sign. Severe stiffness of the hamstrings causes an inability to straighten the leg when the hip is flexed to 90 degrees. Neuro assessment - Sensation Dull vs. sharp – use broken tongue depressor or cotton tip applicator Include face, hands, arms, abdomen, feet, and legs Neuro Assessment Videos Lewis DVD A RN needs an order from a physician to conduct a neurological assessment on a patient showing new symptoms of a CVA. 100% ls e 0% Fa 2. True False Tr ue 1. Altered cerebral function Nursing assessment for Cerebral Dysfunction Terms used to describe LOC Description more important than term Health history- drugs/head injury/metabolic Physical exam- modify as individual cooperation Neuro Vital Signs – LOC, V/S, Pupils, Strength/Movement, Sensation Glasgow coma scale NIH Stroke Scale – want low score – NIH Stroke Scale pdf Common manifestations/Complications Coma states and brain death Irreversible coma- persistent vegetative state – – – Locked-in Syndrome (not true coma) – – Does not have functioning cerebral cortex Caused by anoxia or severe brain injury Sleep-wake cycles; chew/swallow/cough, no tracking Functioning RAS & cortex; pons level interference Aware, communicate with eyes Brain death – Loss of all brain function- flat EEG, no blood flow Prognosis of individual with altered cerebral functioning Outcome varies according to underlying cause and pathologic process The longer the individual unconscious, the longer has absent Doll’s eyes; the poorer the cognitive recovery Residual mental problems typically outweigh the physical Altered Cerebral Function Therapeutic Interventions Diagnostic tests- to R/O & identify cause of altered cerebral function – CT, MRI, EEG, blood work Medications- vary according to problem Overdose; fluid/electrolyte replacement; antibiotics Surgery- (Ex. tumors, intracranial bleeds) Other- airway/vent; treat IICP; enteral feeding Your patient becomes disoriented and reports a severe headache. Which diagnostic test would you expect the physician to order first? 15% 0% d he a Ra y X- C T of of th e th e he EE G ad 0% br ai n 4. ft he 3. 85% RI o 2. MRI of the brain EEG CT of the head X- Ray of the head M 1. Which of the below options would be your priority nursing diagnosis for a patient with altered cerebral function? 69% . nu t.. im ba fo r is k R ce la n e tiv ef fe c In e tiv ef fe c ai rw r.. . pe e tis su as pi ra tio n ay 0% fo r 4. 8% In 3. 23% is k 2. Risk for aspiration Ineffective tissue perfusion Ineffective airway Risk for imbalance nutrition R 1. Altered Cerebral Functioning: Pertinent Nursing problems Identify the priorities: Impaired physical mobility Risk for aspiration Ineffective coping- Family Ineffective tissue perfusion (cerebral) Risk for impaired skin integrity Ineffective airway Risk for imbalanced nurtition Alteration in breathing pattern Home care Increased Intracranial Pressure (IICP) Increased Intracranial PressureOverview Normal ICP Control Autoregulation Causes of Increased ICP Clinical Manifestations Diagnostic Studies Monitoring Increased ICP Treatment ICP Skull is a closed box with three essential components: blood 12%, brain tissue 78%, and cerebrospinal fluid (CSF) 10% Normally, arterial pressure, venous pressure, intraabdominal and intrathoracic pressure, posture, temperature, and blood gases keep ICP relatively constant Monro-Kellie hypothesis Brain tissue, blood, and CSF are mostly constant in volume If the volume of one component increases, another component will be displaced In total, the intracranial pressure will not change while compensation is possible (ex. Change in CSF production or absorption, vasoconstriction or dilation, compression or distention of brain tissue) The ability to accommodate change is limited Measuring Increased ICP Normal ICP is 0 to 15 mm Hg Usually treated once above 20 mm Hg Cerebral Blood Flow (CBF) Cerebral Blood Flow- amount of blood in mls passing through 100g of brain tissue in 1 minute Global CBF is 50ml/min Normal blood flow 25ml/min in white matter Normal blood flow 75 ml/min in gray matter Brain requires constant supply of oxygen and glucose Brain uses 20% of oxygen and 25% of glucose Autoregulation Autoregulation- the automatic adjustment in diameter of cerebral blood vessels to maintain constant blood flow despite changes in blood pressure Autoregulation is not effective with a MAP less than 50 mm Hg Autoregulation is not effective with a MAP greater than 150 mm Hg Autoregulation (Cont’d) Cerebral Perfusion Pressure (CPP)pressure needed to ensure blood flow to the brain CPP= MAP- ICP Normal CPP is 70 to 100 mm Hg CPP < 50 mm Hg causes ischemia and neural death CPP< 30 mm Hg is not compatible with life Factors Affecting Cerebral Blood Flow Increased PaCO2 dilates cerebral vessels Decreased PaCO2 constricts cerebral vessels, increases cerebrovascular resistance, reduces CBF, and decreases ICP Decreased cerebral O2 tension dilates cerebral vessels Cardiac or respiratory arrest Diabetic coma Infections Encephalopathies Cerebral Edema Increased accumulation of fluid in extravascular spaces of brain tissue Results in increased tissue volume Caused by brain abscess, brain tumor, hematoma, hemorrhage, contusion, posttraumatic brain swelling, meningitis, enephalitis, anoxic and ischemic episodes, cerebral infarction, venous thrombosis, lead or arsenic intoxication, hepatic encephalopathy, uremia Three types: vasogenic, cytotoxic, and interstitial (more than one type can occur at the same time) Cerebral Edema (Cont’d) Vasogenic Cerebral Edema– – – – Most common Changes in endothelial lining of cerebral capillaries allow leakage of macromolecules into extravascular space Fluid flows to extravascular space due to osmotic gradient Can be caused by tumors, abscesses, and toxins Cerebral Edema (Cont’d) Cytotoxic Cerebral Edema– – – Occurs most often in gray matter Lesions or trauma cause cerebral hypoxia, sodium depletion, and syndrome of inappropriate antidiuretic hormone (SIADH Fluid then shifts from extracellular space directly into the cells Cerebral Edema (Cont’d) Interstitial Cerebral Edema– Periventricular diffusion of ventricular CSF in a patient with uncontrolled hydrocephalus Causes of Increased ICP Aneurysm rupture and subarachnoid hemorrhage Brain tumor Encephalitis Hydrocephalus Hypertensive brain hemorrhage Intraventricular hemorrhage Meningitis Severe head injury Subdural hematoma Status epilepticus Stroke Source: National Institute of Health Stages of Compliance with IICP 1. 2. 3. 4. Compensation is effective & autoregulation present – CSF, Blood, and Brain Compliance less effective & increase risk for IICP Any small increase in volume causes great increase in ICP, loss of autoregulation & Cushing's triad Herniation Increased Intracranial Pressure (IICP) Cerebral edema/hydrocephalus Cerebral edemaIncreases the volume of brain tissue which can cause herniation Hydrocephalus– Build up of CSF inside the skull Increased intracranial pressure (IICP): Nursing assessment specific to IICP Health history- assess brain involvement Physical exam– – – – – – Altered cerebral function assessment Frequency depends on potential IICP Early sign- change in LOC 3rd Cranial nerve compression- pupil dilation, no response to light, ptosis of the eyelid on ipsilateral side as lesion Papilledema, projectile vomiting, vision changes, seizures Late sign- Cushing’s Traid – Widening pulse pressure (increasing SBP & decreasing DBP) decreased HR, and irregular respiratory pattern Increased Intracranial Pressure (IICP): Therapeutic Interventions Diagnostic tests CT Scan MRI PET EEG Angiography Transcranial doppler studies ECG CBC, Coags, BMP, ABGs, drug screen Increased Intracranial Pressure (IICP): Therapeutic Interventions (Cont’d) Medications– – – – – – – – Osmotic diuretic (Mannitol) Sometimes loop diuretic (Lasix) Antiseizure medications (Dilantin) Corticosteroids (Decadron) (brain tumors, bacterial meningitis) Proton pump inhibitor (Protonix) GI prophylaxis Vasoactive drugs to maintain MAP Barbituates Sedation ICP monitoring LICOX cath – brain tissue oxygenation of frontal white matter PbtO2 – – Jugular venous bulb cath SjvO2 indicates brain tissue removal of O2 from blood – – Normal PbtO2 is 37-47 mmHg LICOX Catheter Normal SjvO2 is 60% to 80% <50 to 55% of O2 in venous blood indicates impairment of flow and brain taking out more O2 than normal ICP Waveforms (P1, P2, & P3) see Lewis p. 1474 – – – P1 arterial pulse wave should be highest P2 is intracranial compliance – if higher than P1 compliance is compromised P3 is the venous pulsation and should be the lowest Intracranial pressure monitoring can be used to continuously measure ICP. The ICP tracing shows normal, elevated, and plateau waves. At high ICP the P2 peak is higher than the P1 peak, and the peaks become less distinct and plateau. ICP Monitoring (Cont’d) Pg 1473 Intraventricular Monitoring: – – – – – – Considered gold standard of ICP monitoring Surgically placed into ventricular system Has drainage bag, pressure transducer, and three way stopcock Accurate, can drain CSF Infection occurs in up to 20% of patients Risk of hemorrhage during placement (2%) ICP Monitoring (Cont’d) Intraparenchymal Monitoring: – – – – – – Inserted into brain parenchyma via small hole drilled in skull Thin cable with fiberoptic transducer at the tip Easier to place, lower risk of infection, lower risk of bleed Cannot drain CSF Not as accurate Mechanically complex design carries greater risk of failure ICP Monitoring (Cont’d) Subarachnoid Monitoring: – – – – Hollow screw placed through skull into dura Dura is then punctured, allowing CSF to communicate with the transducer Frequently clog and are considered unreliable Rarely used ICP Monitoring (Cont’d) Epidural Monitoring: – – – Rest against the dura after passing through the skull Often inaccurate and are of limited clinical utility Used for coagulopathic patients with hepatic encephalopathy ICP Monitoring (Cont’d) Noninvasive Monitoring Tissue resonance analysis (TRA)ultrasound-based method Transcranial doppler Intraocular pressure Tympanic membrane displacement None of above have demonstrated reproducible clinical success at this time ICP Monitoring New Approaches to ICP Monitoring Intraventricular and subarachnoid monitoring devices for IICP Increased intracranial pressure (IICP): Pertinent Nursing Problems and Interventions Ineffective tissue perfusion: cerebral – – – – – – – – Assess/report sign IICP Adequate airway Promote venous drainage Control environment stimuli Plan nursing care – avoid clustering care Avoid Valsalva’s maneuver If bone flap out post op- assess & position Assess external shunts/drains A patient has ICP monitoring with an intraventricular catheter. A priority nursing intervention for the patient is : 1. 2. 3. 4. Aseptic technique to prevent infection Maintain the bed in Trendelenburg position Removal of CSF to maintain normal ICP Sampling CSF to determine abnormalities A patient with an intracranial problem does not open his eyes to any stimulus, has no verbal response except mutturing when stimulated, and flexes his arm in response to painful stimuli. The GCS is: 1. 2. 3. 4. six eight nine eleven Match the following treatment for increased ICP with it’s effect: Oxygen administration 1. 2. 3. 4. 5. Decreased cerebral metabolism Prevention of hypoxia Decreased volume of brain water Cerebral arterial vasoconstriction Decreased lesion edema Match the following treatment for increased ICP with its effect: Mild hyperventilation 1. 2. 3. 4. 5. Decreased cerebral metabolism Prevention of hypoxia Decreased volume of brain water Cerebral arterial vasoconstriction Decreased lesion edema Match the following treatment of increased ICP with its effect: Osmotic diuretics 1. 2. 3. 4. 5. Decreased cerebral metabolism Prevention of hypoxia Decreased volume of brain water Cerebral arterial vasoconstriction Decreased lesion edema Match the following treatment of increased ICP with its effect: Dexamethasone (Decadron) 1. 2. 3. 4. 5. Decreased cerebral metabolism Prevention of hypoxia Decreased volume of brain water Cerebral arterial vasoconstriction Decreased lesion edema Match the following treatment for increased ICP with its effect: Barbiturates 1. 2. 3. 4. 5. Decreased cerebral metabolism Prevention of hypoxia Decreased volume of brain water Cerebral arterial vasoconstriction Decreased lesion edema VP shunt (a narrow piece of tubing) is surgically placed in the ventricle of the brain to drain CSF to the abdomen where it is absorbed by the body. CSF Shunt After VP Shunt Surgery There is mild pain involved with this surgery. Acetaminophen (Tylenol ) or ibuprofen may be used for postoperative discomfort. You will be in the hospital for 1 - 3 days. Once you are eating and drinking, and there are no complications, you will be able to go home. You will have a follow-up appointment in the neurosurgery clinic in 7-10 days. Your head dressing and staples will be removed at that time. After discharge, you may resume your regular activities unless you are told otherwise. In the future, you will need antibiotics before dental work and other invasive procedures. After VP Shunt Surgery (Cont’d) When to Call your Neurosurgeon or Nurse Practitioner Sometimes a shunt malfunctions by becoming clogged, disconnected, or infected. If this happens, you may experience any of the following signs and symptoms: Redness, pain or swelling of the skin along the length of the shunt or at the incision sites Drainage from the incision Fever greater than 101.5° F-usually within the first six months of surgery Irritability or excessive sleepiness Nausea or vomiting Recurring headaches Blurred or double vision Sudden or gradual change in personality Rubbing of the head Weakness Balance or coordination problems Brain Herniation Brain Herniation Cingulated Herniation - a •Cingulate gyrus slips under falx cerebri •Usually caused tumor or bleed •Non life threatening Brain Herniation Uncal or Lateral Herniation - b •Uncus of temporal lobe slips through notch of tentorium and compresses the ipsilateral CN 3, brainstem, & vital centers • Life threatening Brain Herniation Central or Transtentorial Herniation - c •Caused by: downward pressure on mid structures of cerebrum or general cerebral edema which compresses the brainstem • Life threatening – compresses RAS & vital centers •Abnormal heart rhythms, disturbances or cessation of breathing, cardiac arrest, and death Brain Herniation Extracranial Herniation - d •Occurs with displacement of brain through a cranial defect. •Usually Non-life threatening Brain Herniation Infratentorial (subtentorial or Tonsillar) Herniation - e •Downward displacement of infratentorial structures through the foramen magnum • Life threatening The End!