Neurosensory: Altered Cerebral Function and Increased intracranial pressure (IICP)

1. Neurosensory:Altered Cerebral Function and Increased intracranial pressure (IICP) Marnie Quick, RN, MSN, CNRN

2. Etilogy/Patho Altered Cerebral Function: Consciousness • Dynamic state in that it fluctuates • Continuum from awareness of self and environment to unawareness • Consciousness to deep coma • Caused by: • lesions/injury to the reticular system or cerebral cortex • Metabolic disorders

3. Altered Cerebral Function: Arousal/cognition (LOC) Patho/assessment • Reticular Activating System (RAS) meshwork of gray cell within brainstem/thalamus. Controls wakefulness, arousal and alertness. • Cerebral cortex outer layer of gray cell bodies of brain. Controls cognition, thought process.

4. Reticular Activating System (RAS)

5. Altered Cerebral Function: Assessment of arousal/cognition (LOC) • Observe individual’s behavior, call name • Verbal response to person/place/time/event • If unable- how responds to commands • If unable- how responds to central pain stimuli

6. Assessment of arousal/cognition (Respiratory and pupillary light reflex) • Respiratory- changes occur as brainstem is being compressed • Pupillary light reflex- Sensory: CN 2 Motor: 3 • Note pupil size; darken room; shine light in and note reaction and size • Direct/consensual

7. Assessment Arosual/cognition (EOM’S) • Eye movement- CN 3,4,6 • In COMA- test EOM’s Oculocephalic reflex • Doll’s eyes- Sensory- CN 8; Motor- CN 3,4,6 • Good Dolls eyes: eyes move in opposite direction of head movement • Bad/negative Dolls eyes: eyes do not move head turned

9. Assessment arousal/cognition (Motor) • Strength, symmetry and ability to move • Order from best to worse: • Purposeful • Generalized response • Posturing- flexion or extension • Flaccid • Planter Reflex- Babinski testing • Meningeal signs- Brudzinski, nuchal rigidity

11. Decorticate posturing- abnormal flexion Decerebrate posturing- abnormal extension

12. Planter Reflex and Babinski testing

13. Common manifestations/Complications Coma states and brain death • Irreversible coma- persistent vegetative state • Does not have functioning cerebral cortex • Caused by anoxia or severe brain injury • Sleep-wake cycles; chew/swallow/cough, no track • Locked-in Syndrome (not true coma) • Functioning RAS/cortex; pons level interference • Aware, communicate with eyes • Brain death • Loss of all brain function- flat EEG, no blood flow

14. 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 problem typically outweigh the physical

15. Altered Cerebral Function Therapeutic Interventions • Diagnostic tests- to R/O & identify cause of altered cerebral function • Medications- Isotonic IV; D50; treat narcotic overdose; fluid/electrolyte replacement; antibiotics • Surgery- to remove cause • Other- airway/vent; treat IICP; enteral feeding

16. Nursing assessment specific to altered cerebral function • Terms used to describe (p.1347) • Description more important than term • Health history- drugs/head injury/metabolic • Physical exam- modify as individual cooperation • Neuro Vital Signs (p.1299) • Glasgow coma scale (p. 1299)

17. Altered Cerebral Functioning: Pertinent Nursing problems • Ineffective airway • Risk for aspiration • Risk for impaired skin integrity • Impaired physical mobility • Risk for imbalanced nurtition • Ineffective coping- Family • Home care

18. Increased Intracranial Pressure (IICP) Normal Brain • Monro-Kellie hypothesis • Intracranial pressure:5-15 mmHg;60-180cm H2O • Cerebral perfusion pressure: MAP-ICP=CPP; Normal: 80-100 mmHg; minimal blood flow 50; brain death 30 mmHg • Autoregulation- cerebral arterioles change diameter to maintain CBF when ICP rises; need nomal range of MAP to occur; pressure (BP) and chemical (CO2) autoregulation

19. Increased Intracranial Pressure Pathophysiology of intracranial hypertension • Monro-Kellie hypothesis • Cushing reflex- BP and Pulse • Brain shifts- herniation syndromes • Symptoms progress in relation to these physiological changes

20. Increased Intracranial Pressure (IICP) Cerebral edema/hydrocephalus • Cerebral edema- Increases the volume of brain tissue which can cause herniation • Hydrocephalus- • Noncommunicating • Communicating

21. Subarachnoid space with arachnoid villi

22. Increased Intracranial Pressure (IICP) Brain Herniation Syndromes • Cingulate herniation • Central (transentorial) • Uncal (lateral) • Infratentorial herniation • Extracranial herniation

23. Brain herniation

24. Normal brain and Herniation Syndromes

25. Increased Intracranial Pressure Common manifestations/complications • Result of compression of brain function • Level of consciousness most important sign • Second- pupil changes as 3rd nerve is compressed • Others- p.1355 • Speed of IICP how fast cause develops • Cushing reflex late sign • Complication of IICP is permanent disability, coma, death

26. Increased Intracranial Pressure (IICP): Therapeutic Interventions • Diagnostic tests- to find cause; monitor hydration/O2 • Medications • Osmotic/loop diuretics; antipyretics; anticonvulsants; antiulcer; IV fluids; TPN; vasoactive drugs for MAP; barbiturate coma • Hypothermia • Surgery- remove cause; shunt/drain • Mechanical ventilation • ICP monitoring • Other monitors- Jugular venous O2; partial pressure O2 in brain tissue

27. Intraventricular and subarachnoid monitoring devices for IICP

29. Intraventricular drainage system

30. 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 • Papilledema, projectile vomiting, vision changes, seizures (p. 1355) • Late sign- Cushing VS changes– Know!

31. 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 Valsalva’s maneuver • If bone flat out post op- assess • Assess external shunts/drains