Increased Intracranial Pressure and Traumatic Brain Injury

What nutritional therapy considerations would a patient with IICP need?

Being in a hypermetabolic and hypercatabolic state increases the need for glucose so you have to ensure they are getting nutrition, either through enteral or parenteral routes. Starting feeds within 3 days of injury promotes better outcomes. Keep patient normovolemic and use IV 0.9% NaCl

How does controlled hyperventilation help with IICP? What are the risks?

It blows off CO2 which causes vasoconstriction of arterioles which decreases cerebral blood volume (thus decreasing ICP), recent research says it may or may not be helpful, have to be careful because severe hypocapnia causes ischemia

Why would you avoid valsalva maneuver and straining in a patient with IICP?

It increases intraabdominal and intrathoracic pressure which further increase ICP

Cushing's triad (what is it a sign of, what are the manifestations)

Late sign of increased ICP, made up of increased systolic BP (widened pulse pressure), bradycardia with bounding pulse, and irregular respirations

What are the types of skull fractures?

Linear nondisplaced, depressed, compound, penetrating objects, basilar

What is diabetes insipidus?

Loss of large volumes of dilute urine in the presence of normal or high plasma osmolality

How and why would you maintain a controlled metabolic rate with an IICP patient?

Maintain a normal temperature, prevent seizures, control blood sugar, control pain and anxiety - neuromuscular blockers: vecuronium bromide (Norcuron) - sedatives: Propofol

What drug would you use for getting rid of edema/fluid and what are the considerations for it?

Mannitol- osmotic diuretic - need to give through a filtered needle - rapid onset of 15 minutes - main side effect is dehydration - assess urine output, I&O, and serum osmolarity

What are the components of a neurologic examination?

Mental status: oriented x3? Level of consciousness PERLA Cranial nerve function Cerebellar function (romberg) Reflexes (gag, cough, deep, babinski) Sensory and motor function bilaterally

Care for a basilar skull fracture

Minimize coughing, sneezing, valsalva maneuver, no nasal suctioning or nasogastric tube, do not pack ears or nose if there is a CSF leak (use a sterile nonocclusive gauze), assess for infection

Why do we want to prevent repeated concussions?

Multiple concussions can cause permanent injury or lead to chronic traumatic encephalopathy

Care for a depressed skull fracture

Need protective device/helmet, position them so they aren't leaning on the depressed area, debride and irrigate wound, if it is more than a 5 mm depression they may undergo acrylic cranioplasty

What are some indicators of brain death?

Negative oculocephalic response, negative oculovestibular response, no corneal reflex when stimulated, can't breathe on own off ventilator

What diagnostic tools would you use for IICP/TBI?

Neurologic examination, monitoring devices for ICP, vital signs assessment, CT scan, MRI, transcranial doppler, cerebral arteriogram

What are the rating categories for best motor response (GCS)

No response (1), extension/decerebrate (2), abnormal flexion/decorticate (3), withdrawal flexion (4), localizes pain (5), obeys commands (6)

What are the rating categories for best verbal response (GCS)

No response (1), incomprehensible sounds (2), inappropriate words (3), disoriented and converses (4), oriented and converses (5)

What are the rating categories for eyes (GCS)

No response (1), open to pain (2), open to verbal command (3), open spontaneously (4)

Basilar skull fracture

Occurs at base of skull, top of neck, near spine, manifested by racoon's eyes, battle's sign, otorrhea or rhinorrhea, halo or ring sign

What are the cranial nerves (in order)

Olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal

How would you assess each cranial nerve?

Olfactory: have them identify smells Optic: snellen chart or read something Oculomotor: cardinal fields of vision Trochlear: cardinal fields of vision Trigeminal: have them clench jaws Abducens: cardinal fields of vision Facial: have them smile Vestibulocochlear: check hearing and balance Glossopharyngeal: assess swallowing and gag reflex Vagus: assess heart rate Accessory: have them push shoulders against resistance Hypoglossal: have them stick out tongue

Craniectomy

Opening up the skull and removing the bone flap - resolves IICP resulting from midline shifts - brain needs room to swell for weeks to months

Craniotomy

Opening up the skull but putting the bone back

What is your oxygenation goal for someone with IICP?

PbO2 20-40 mmHg

Barbiturate coma

Pentobarbital IV drip or IVP depresses the CNS, CV, and respiratory systems - alters assessment - need mechanical ventilation and total physical care - may assess effectiveness with EEG or BIS - drug holidays and inform family of effects

How would you position someone with IICP?

Position with head of bed elevated to promote jugular venous drainage, head in alignment with body when positioning

Why wouldn't you do a lumbar puncture for IICP patients?

Pulling off fluid with suction can cause brain herniation

What would you be looking for/to prevent with a vital signs assessment?

BP needs to be maintained to perfuse the brain so you need to watch for and avoid hypotension, treat bradycardia less than 40-50, watch for cushing's triad

What is the normal serum osmolarity?

260-300 mmHg

Normal intracranial pressure

5-15 mmHg

What are the normal and bad ranges for CPP?

60-100 mmHg is normal, less than 50 is ischemia/death

Why are neuro examinations important diagnostic/monitoring tools for IICP/TBI patients?

Allows you to closely monitor for changes that could indicate worsening injury to brain/increasing pressure

What are the early, moderate, and late manifestations of IICP?

Early: changes in level of consciousness and confusion Moderate: LOC changes, motor changes, pupil changes, disconjugate eye movement, vomiting, headache, papilledema Late signs: fixed pupils, extreme motor changes or no response, loss of reflexes, cushing's triad

What is the major diagnostic test for IICP?

CAT scan

How to calculate CPP

CPP= MAP-ICP

Epidural hematoma characteristics

Caused by interruption of the middle meningeal artery (on the side of head), fast bleed above the dura -classic s/s: loss of consciousness, awake, then coma

Subdural hematoma characteristics

Caused by tearing of bridging veins between brain and dura, blood pools between the dura and the arachnoid membrane - because it is a venous bleed the s/s do not happen as fast - acute signs happen in 24-48 hours

Why would you use therapeutic hypothermia?

Cooling of the body less than 36 degrees celsius protects the brain by inhibiting depolarization, stabilizing the blood brain barrier, decreasing cerebral metabolic rate, which causes a decrease in CO2 and lactate - initiate early with a duration of 24 hours

Care for a linear nondisplaced skull fracture

Debride and irrigate wound if needed, assess for infection

What would decorticate or decerebrate movements look like in a patient?

Decorticate is when they pull their arms towards their core, decerebrate is when they extend their feet out

What are the side effects of therapeutic hypothermia?

Decreased cerebral perfusion, MAP, HR, hypokalemia, atelectasis, pneumonia, ARDS, rebound hyperemia, and cerebral edema during rewarming

What are the complications of IICP and TBI?

Diabetes insipidus and brain herniation

Causes of IICP

cerebral edema, concussion, contusion, hematoma, hydrocephalus, tumor

Why does Diabetes Insipidus happen with IICP?

Traumatic brain injury causes dysfunction of hypothalamic neurons secreting antidiuretic hormone

How would you care for a patient with IICP?

Treat underlying cause, positioning, intubation, mechanical ventilation, oxygenation and CO2 levels, avoid isometric exercise, bearing down, and sneezing, IV therapy, nutritional therapy, controlled hyperventilation, controlled metabolic rate, therapeutic hypothermia, barbiturate coma, continuous EEG monitoring

What types of monitoring devices are there for ICP?

Ventricular catheter (also for draining), ventriculostomy, LICOX catheter

Why does brain herniation happen with IICP?

Ventricular shift caused by increased pressure causes the brain to herniate because it doesn't have anywhere to go. Often caused by subdural hematomas

Intracerebral hematoma characteristics

also called a cerebral hemorrhage or hemorrhagic stroke, greater than 5 ml of blood -s/s depend on location, size, and rate of blood accumulation

Concussion symptoms

headache, N/V, incoordination, dizziness, visual problems, fatigue, difficulty thinking or concentrating, feeling slowed down, more emotional than usual

How do you treat diabetes insipidus in an IICP patient?

need to correct the underlying cause, then fluid replacement with IV hypotonic solutions, IV vasopressin

Glasgow coma scale

score is from 3-15, you want a higher number b/c anything less than 8 is a major brain injury, categories are eyes, best motor response, best verbal response