Advanced Neurological Concepts in Critical Care

Neurological Cerebral Vascuar Accident DUE TO: iscehmic or hemorrhagic event -can wind up being a TIA, RIND, or CI → Basilar Vertebral Artery, Carotid Artery -TIA: all better after 24 hours -RIND: reversible ischemic neurological deficit -long TIA, longer than 24 hours, lasts for about 3 months -ex. Guy has a stroke, can't move one side, weeks and months go by, start to move that side, in a wheelchair, then a cane, then resolves (in the hospital longer) -CI: Cerebral Infarct, dead tissue forever *2 blood supply systems to brain: Basilar Verterbral Artery, Carotid Artery *Carotid- would rather have a stroke here (infarct affects one side of body, etc) -one sided weakness, one sided paraesthesias, hemiplegia, etc. *Basilar Verterbral- supplies brain stem (stroke would infarct somewhere in brain stem) *Hemonymous Hemoniopia: caused by a carotid ischemic event or hemorrhage, blindness in one half of both eyes (ex. If right side was infarcted, you would have right sided hemonymous hemoniopia) **if you have an infarct on the left side, eyes always look left (EYES LOOK TO THE BOO BOO.. HEY! WHAT'S GOING ON OVER HERE?!) *ex. Right side infarct or hemorrhage-- right sided weakness, ride sided plegia, right sided hemonymous hemoniopia, BUT LEFT eye deviation (eyes look to left side) Neuro Anatomy Cortex: problem= decorticate (hands flexed up to core) Brainstem: midbrain, pons, medulla = decerebrate (hands extended down and out) 2 holes in head: Tentorial notch, foramen magnum (down at the bottom below brain stem) -If herniating down foramen magnum → brian is leaving your head -holes decrease ICP to allow swollen brain to expand Pyramidal tracts: start on one side of the brain, cross over and go on other side of cord, motor tracts → they make you move! -if you have an injury to the pyramidal tract, you get a babinski -injury opposite of babinski → left injury = right babinski, right injury = left babinksi, bilateral injury = bilateral babinski Pupils: innervated by CN 3, parasympathetic innervation (pinpoint), sympathetic inneration (dilate) -where parietal and temporal meet is the weakest part of your head, this is where meningeal artery is, drunk people often fall and hit this part of the head (fall to the side- staggering sideways) → epidural bleed *Epidural bleed → head shifts LATERALLY **Uncal herniation = lateral shifting of brain in the head -expanding mass knocks off parasympathetic innervation of pupil, leaves only sympathetic innervation → DILATED PUPIL ON SIDE OF INJURY! **Uncal herniation = IPSILATERAL DILATED PUPIL! NO CHANGE IN LOC! *Supratentorial Herniation- whole brain is coming on down -diffuse edema **CHANGE IN LOC (early sign), then → DILATED PUPILS (late sign)\ ***Cushing's Triad- INCREASED systolic BP, WIDENING pulse pressure, DECREASED HR and RR -widening pulse pressure due to increased systolic BP (ex. 200/70, then 250/70) -CUSHING'S = SIGN OF HERNIATION! **WITH ANY DOWNWARD SHIFT = CHANGE IN LOC (SUPRATENTORIAL HERNATION), AS BRAIN CONTINUES TO GO DOWN, KNOCKS OF PARASYMPATHETIC INNERVATION OF PUPILS, THEN → PUPIL CHANGE, DOWN THRU FORAMEN MAGNUM = DEATH **WITH LATERAL SHIFT = NO CHANGE IN LOC, PUPIL CHANGE ONLY (UNCAL HERNATION) Glasgow Coma Scale (GCS) Eyes Open → 4- Spontaneous 3- To Commands 2- To Pain 1- No Response Motor → 6- Obeys Commands 5- Localizes Pain 4- Withdraws from pain 3- Abnormal Flexion (Decorticate posturing) 2- Abnormal Extension (Decerebrate posturing) 1- No response (No movement) Verbal → 5- Oriented 4- Confused 3- Inappropriate Words 2- Incomprehensible Sounds 1- No Response Increased ICP AVOID: -Acidosis: acidosis vasodilates blood vessels and increases ICP, keep pt alkalotic with high ICP -Hypotonic Solutions: they go in the cell, give hypertonic solutions to draw water out of the cell -Hyperextension/Flexion: do not flex neck and head, log roll in bed -Decreased Protein: feed them (when protein levels drop, lose oncotic pressure and fluid goes into cell and causes more cerebral edema), ensure adequate caloric pressure -Wrist Restraints: increases ICP up to 50 pts -Stroke: most s/s are due to TEMPORARY cerebral edema (increased ICP) -NPO, restraints, turning, hypotonic solution (D5W since NPO) all cause worsening cerebral edema and woresning s/s CPP = MAP – ICP MAP = Diastrolic Pressure + 1/3 Pulse Pressure ex. MAP = 80, ICP = 10, CPP = 70 **Normal CPP = 70-95 Basilar Skull Fracture -Raccoon Eyes -Battle Sign- black and blue on the mastoid bone -Otorrhea- drainage from ears -leakage of CSF from ears is usually bloody, how would you know if its CSF or blood? -HALO sign → clot has a yellow ring around it, put on gauze -Rhinorrhea- drainage from nose -usually clear liquid from nose, how do you know if its CSF? -test for glucose, if positive glucose = CSF → CSF has glucose, nasal drainage doesn't -NO Tissues! Put an abd pad or gauze under their nose -Lose Cranial Nerve 1 (lose sense of smell) -cannot see basilar skull fx on xray Brown-Sequard Syndrome -ipsilateral motor loss -contralateral loss of pain and temperature -hemisection of cord (half the spinal cord is cut) -the side that is cut (side of the injury) you lose motor, opposite side you lose sensation and temperature -the tracks that go down = motor, tracks that go up = sensation -motor starts up in the brain as opposite and crosses down the cord, sensation is opposite -ex. If hand is on fire, sensory tracts work first (feel it first), then crosses the cord and goes up to motor sensor in brain and you move your hand -ex. Right injury → right motor loss, left sided sensation loss ex. trauma gun shot wound -can't move one side but can feel, can move other side but cant feel it Central Cord Syndrome -UPPER motor loss -jump out of building and land on feet and compress cord → pinch off all the nerves going to upper body -kids in grocery store -alcoholic pt who fell on stairs (loss of upper fine motor function) Bacterial vs Viral Meningitis Bacterial -usually due to staphylococcus aureus -very elevated protein -low glucose! -purulent (cloudy) CSF -leukocytes (WBCs) Viral -usually due to enterovirus or herpes virus -elevated protein -normal glucose! -clear -lymphocytes *S/S of bacterial and viral meningitis: headache, nuchal rigidity, brudzinski's sign, kernig's sign -nuchal rigidity = stiff neck -brudzinski= take chin and put to chest, legs fly up -kernig- extend their leg out, pain in hamstring and neck Dolls Eyes Reflex: lift eyelids of unconscious person, eyes always return to midline when head turned side to side, oculocephalic reflex = brain stem integrity (eyes are always looking at you) **contraindicated with cervical neck injury (c-spine) Practice Questions 1) The single most important index of neurological state is the: -Level of consciousness 2) Quick rotation of the head back and forth while holding the eyes open causing the eyes of the comatose patient to rotate opposite the side toward which the head is turned is a positive response known as: -Oculocephalic Reflex (Dolls Eyes Reflex) 3) The response elicited when the neck is flexed, producing flexion of both thighs at the hips, as well as flexion movements of the ankles and knees is called: -Brudzinski's Sign 4) The respiratory pattern seen in upper brainstem lesion (midbrain) is: -Hyperventilation *Midbrain problems = hyperventilate (blow off CO2 and put yourself in alkalotic state) *Apneustic breathing = pontene problem (Pontene has P, apneustic has P) 5) A 26 year old male is complaining of a severe headache. On assessmnet, he has a nuchal rigidity, and a positive Kernig's sign. Which of the following is most likely present? -Subarachnoid Hemorrhage 6) The classic CV signs of increasing ICP known as Cushing's triad include? -Decreased pulse, increased systolic BP, widening pulse pressure 7) Ventricular fluid pressure is the most sensitive indicator of increased ICP. The normal ventricular fluid pressure is: -0-10 mmHg 8) A patient has a subarachnoid screw inserted to monitor his ICP and cerebral perfusion pressure (CPP). The ICP and CPP are both 35 mmHg. This means that this patient's: -Cerebral blood flow has markedly decreased to the brain -problem = CPP is low, ICP is high (no perfusion) 9) Which of the following parameters are graded when using the Glasgow Coma Scale in the assessment of the patient with an altered state of consciousness? -eye opening, motor response, and verbal response 10) Blindness in one hald of both visual fields following a CVA is referred to as: -Hemonymous Hemianopia 11) Patients with injury to the left cerebral hemisphere may exhibit: -Deviation of the eye to the left 12) Pinpoint pupils that react to light if viewed with a magnifying glass are indicative of: -A lesion in the pons (pintpoint pupils = pontene infarct) -sympathetic innervation goes up through the pons -parasympathetic innervation goes up through the midbrain -pontene infarct is dead tissue, so you lose the sympathetic innervation and you only have the parasympathetic innervation of the pupil, so it becomes pinpoint -pontene infart also = apneustic breathing (prolonged pauses between exhaling and inhaling), they take a long inhale and you're waiting for them to exhale (call a code.. no nevermind!) 13) The nurse caring for a patient with a supratentorial herniation understands that the earliest sign would be: - Lethargy and Stupor 14) Which of the following treatment modalities would the nurse consider to be inappropriate for the ventilator patient with increased ICP? -Administering D5W at 75 cc/hr (hypotonic solution increases brain swelling) -would want to keep the pt acidodic (CO2 between 29-33) ex. kid with head trauma and DKA (do not give hypotonic even though DKA because head comes firs t) 15) While assessing the laboratory data of a patient with head trauma, which finding necessitates notification of the physician? -A urine specific gravity of 1.005 → indicates DI, head trauma is the number 1 cause! 16) A Basal Skull fracture affecting the middle fossa may cause which of the following? -Cranial Nerve Injuries (1) -Battle's Sign -CSF Otorrhea and Rhinorrhea 17) What should the nurse do when his/her patient with a basilar skull fracture begins to have clear fluid draining from one ear? -Apply a loose sterile dressing over the ear and call the doctor 18) To determine if bloody head drainage contained CSF, a nurse would put some gauze on it and observe: -a blood clot in the middle with a yellow ring around it 19) A patient who has a neurological injury that results in ipsilateral motor loss and contralateral loss of pain and temperature is said to have: -Brown-Sequard Syndrome 20) Examination of CSF in bacterial meningitis will reveal all but which of the following? -decreased protein -CSF with bacterial meningitis will have: cloudiness, increased WBCs, increased pressure and decreased glucose, very incrreased protein 21) Which statement is accurate regarding the differentiation of CSF in bacterial and viral meningitis? -high level of protein in bacterial than viral meningitis, low sugar content seen in bacterial, usually normal in viral, CSF purulent and turbid in bacterial, but clear in viral ***Obtunded is BETTER than stuporous → -Obtunded = look dead, but when shaken, opens eyes and speaks clearly -Stuporous = looks dead, when shaken, mumbles incomprehensible sounds (gargles) **Stuporous people GARGLE, Obtunded people SPEAK!