Critical Care Exam 3 — Neuro questions well answered graded A+

Critical Care Exam 3 — Neuro
questions well answered graded A+

Increased Intracranial Pressure values - ANS ✔✔Normal ICP is 0-15 mm Hg (5-15 mm Hg)



20 mm Hg or greater persisting over 5 minutes = life threatening



Intracranial pressure-volume curve - ANS ✔✔. Between points A and B, intracranial compliance
is present. Intracranial pressure (ICP) is normal, and increases in intracranial volume are
tolerated without large increases in ICP. As compliance is lost, small increases in volume result in
large and dangerous increases in ICP (points C and D).



Brain herniation - ANS ✔✔Herniation can occur above and below the tentorial membrane.
Supratentorial: 1, uncal (transtentorial); 2, central; 3, cingulate; 4, transcalvarial (external
herniation through an opening in the skull). Infratentorial: 5, upward herniation of cerebellum;
6, cerebellar tonsillar moves down through the foramen magnum.



Increased Intracranial Pressure Assessment - ANS ✔✔Assess LOC, which is the most sensitive
and earliest indication of increasing intracranial pressure



Declining LOC from restlessness to confusion and coma



Headache



Elevated temperature, slowing of pulse, abnormal respirations



Rise in blood pressure with widening pulse pressure

,Vomiting



Pupil changes **

----Hypoxia and medications may also influence pupillary size and reactivity to light.




Changes in motor function from weakness to hemiplegia, a positive Babinski's reflex,
decorticate or decerebrate posturing, and seizures



decorticate and decerebrate posturing, - ANS ✔✔Flexor posturing (decorticate).

Extensor posturing (decerebrate)



A Babinski reflex - ANS ✔✔is present when dorsiflexion of the great toe with fanning of the
other toes is noted upon stimulation. In an adult, the presence of a Babinski reflex is a sign of an
upper motor neuron lesion and damage to the corticospinal tract



Pupillary Function - ANS ✔✔Size (in millimeters)

--Oculomotor nerve (CN III)



CN III compression - dilation, nonreactive



Change or inequality

---Increased ICP; danger of herniation



Shape

-Oval - increased ICP

,Reaction to light

--Optic nerve (CN II) and Oculomotor nerve (CN III)

--Direct light response

--Consensual response



Eye movement



Increased Intracranial Pressure late signs - ANS ✔✔Late signs of increased ICP include increased
systolic blood pressure, widened pulse pressure, and slowed heart rate (Cushing's triad)



Monitor GCS based on patient acuity, usually q 1 hour!!



Observe for evidence of CSF leak in ears or nose



Cushing's triad - ANS ✔✔increased systolic blood pressure,



widened pulse pressure,



and slowed heart rate



Assessment of Ocular Function in the Unconscious Patient Doll's Eyes - ANS ✔✔Doll's Eyes
(Oculocephalic Reflex)

--Must have absence of cervical injury



Absent Doll's eyes

--Oculocephalic reflex arc is not intact

, --Significant brain stem injury



Assessment of Ocular Function in the Unconscious Patient Oculovestibular reflex - ANS
✔✔Oculovestibular reflex

-Cold caloric test

-1st check that tympanic membrane is intact



No response

-Little or no brainstem

function



Increased Intracranial Pressure Interventions - ANS ✔✔***Remember that you want the most
optimal hemodynamic status in your patient!***




Elevate the head of the bed 30 to 45 degrees as prescribed



Avoid Trendelenburg's position



Prevent flexion of the neck and hips, maintain neutral position of head



Monitor respiratory status and prevent hypoxia



Maintain mechanical ventilation as prescribed, (* keep within normal range: careful with
decreased PaCO2) AND remember that increased PaCO2 causes vasodilation (Sole et al. 2017, p.
362)