Acute Intracranial - Student

Acute Intracranial Problems

• Presenter: Jessie Seeck, MSN-Ed, RN

• Institution: St. Louis Community College - Wildwood

Intracranial Pressure (ICP)

• Components Affecting ICP:

  • Brain tissue

  • Blood

  • Cerebrospinal fluid (CSF)

• Factors Influencing ICP:

  • Arterial pressure

  • Venous pressure

  • Intra-abdominal and intrathoracic pressure

  • Posture

  • Temperature (fever increases ICP)

  • Blood gases (increased CO2 levels dilate vessels)

Intracranial Pressure Measurement

• Possible Locations for Measurement:

  • Ventricles

  • Subarachnoid space

  • Subdural space

  • Epidural space

  • Brain tissue via pressure transducer

• Monro-Kellie Doctrine:

  • If one component increases, another must decrease to maintain ICP.

  • Limited ability to compensate for volume changes.

  • Normal ICP range: 5 to 15 mm Hg, elevated if >20 mm Hg sustained.

Cerebral Blood Flow (CBF)

• Influence of PaCO2 on CBF:

  • Increased PaCO2 leads to:

    • Relaxation of smooth muscle

    • Dilation of cerebral vessels

    • Decrease in cerebrovascular resistance

    • Increase in CBF

  • Decreased PaCO2 results in:

    • Constriction of cerebral vessels

    • Increased cerebrovascular resistance

    • Decreased CBF

• Oxygen and Glucose Usage:

  • Brain consumes 20% of body’s oxygen and 25% of glucose.

• Autoregulation:

  • Adjusts diameter of blood vessels to ensure consistent CBF (effective with MAP 70-150 mm Hg)

  • Intervention necessary when MAP < 65.

Increased Intracranial Pressure (IICP)

• Primary Considerations:

  • Unconscious patient should be suspected of IICP (life-threatening, poor prognosis).

  • Common causes:

    • Mass (hematoma, abscess, tumor)

    • Cerebral edema (head injury, brain inflammation)

  • CT and/or MRI used for identification; L.P.s not performed with suspected IICP.

IICP Clinical Manifestations

• Change in Level of Consciousness (LOC):

  • Most sensitive and reliable indicator.

  • Subtle shifts (flattened affect, change in orientation, decreased attention).

• Cushing’s Triad:

  • Symptoms: Systolic hypertension with widening pulse pressure, bradycardia, irregular respirations.

  • HIGH BP, LOW PULSE, LOW RESPIRATIONS

• Other Symptoms:

  • Temperature changes

  • Headache

  • Positive Babinski Reflex

  • Vomiting

• Ocular Signs:

  • Ipsilateral pupil dilation, ptosis

  • Contralateral hemiparesis or hemiplegia

  • Posturing: Decorticate & Decerebrate types.

Pediatric Considerations

• Signs and Symptoms in Infants:

  • Sunsetting sign

  • Bulging anterior fontanelle

  • High-pitched cry

  • Seizures

  • Decreasing LOC

  • Cushing’s triad

  • Posturing

Posturing Types

• Decorticate:

  • Flexion of arms, wrists, and fingers, with adduction in upper extremities; extension in lower extremities.

• Decerebrate:

  • All four extremities in rigid extension with hyperpronation of forearms.

Changes in Vital Signs and Other Symptoms

• Increased ICP symptoms include:

  • Changes in LOC

  • Ocular symptoms (papilledema, pupillary changes, impaired eye movement)

  • Posturing variations

  • Changes in speech

  • Headaches and seizures

  • Vomiting, irregular respiration patterns.

Dangers of IICP

• Complications:

  • SIADH:

    • Excessive ADH leading to oliguria and hyponatremia, h/a, weakness, weight gain, cerebral edema, confusion, seizures, and potentially coma if left untreated.

    • Treatment: Fluid restriction, hypertonic saline, and furosemide.

  • Diabetes Insipidus (DI):

    • Deficiency of ADH causing polyuria and hypernatremia, fatigue, dehydration, increased thirst, and potential for severe electrolyte imbalances.

    • Treatment: Fluids and desmopressin. (DDAVP, antidiuretic)

  • Seizure activity may occur due to the rapid fluctuations in sodium levels, necessitating close monitoring of electrolyte balance during treatment.

Herniation

• Occurs when brain tissue is shifted, leading to:

  • Downward displacement of cerebellum through foramen magnum.

  • Risk of respiratory arrest from brainstem compression.

• Clinical Manifestations:

  • Fixed/dilated pupils, deteriorating LOC, Cheyne-Stokes respiration, posturing, Cushing’s triad.

Monitoring and Treatment of ICP

• Monitoring Techniques:

  • Ventriculostomy provides pressure monitoring and CSF removal.

  • Intraventricular drug administration.

  • Transducer must be aligned with the tragus of the ear.

  • Risk of infection. Proper management of the ventriculostomy system is essential to prevent complications such as catheter obstruction and hemorrhage.

• Treatment Approaches:

  • Treat underlying causes (blood hemorrhage, edema, tumor, CSF issues).

  • Fever management, seizure precautions/medications.

  • Employ stimulation reduction strategies and maintain proper head positioning (HOB 30 degrees). Cluster care, dark room.

  • Mechanical ventilation- hyperventilate for brief periods (after initial 24hrs)

  • Surgical intervention for significant hematomas or tumors.

    • Craniectomy; removal of part of the skull.

Medications for IICP

Mannitol

• Osmotic diuretic that decreases IICP by drawing water into the renal system.

• Mannitol is a sugar alcohol (or sugar substitute) that is commonly used as an osmotic diuretic. It works by increasing the osmolarity of blood and filtrate in the kidneys, which leads to the movement of water into the renal tubules, promoting urine production

• Reduces fluid volume systemically.

• USES:

  • Decreases ICP by reducing cerebral edema, thereby improving cerebral perfusion and oxygenation. (brain tumor, cerebral edema)

  • Reducing Intraocular pressure, tx of acute glaucoma.

  • Acute renal failure- promotes urine output in some cases of ARF and helps prevent further renal damage by ensuring adequate renal perfusion.

  • Drug overdose- helps flush out certain toxins.

• Typically given IV, bolus and/or continuous infusion.

• Monitor:

  • Vital signs- BP and HR - mannitol can cause hypotension and electrolyte imbalances due to fluid shift.

  • Assess dehydration ( hyponatremia, hyperkalemia)

  • Monitor urine output- sudden drop could indicate renal dysfunction.

  • Watch for fluid overload- fluid shifts could lead to pulmonary edema if done to quickly.

  • Check for crystals- mannitol can crystallize in solution, warm the solution if any are present.

• Adverse Effects: Hypotension, dizziness, electrolyte imbalances, headache, N/V, pulmonary edema.

• Contraindications: Anuria (lack of urine production) severe renal impairment, severe dehydration or hypovolemia, active intracranial bleeding.

• Patient education: Maintain fluid balance, report changes in urine output, or signs of fluid overload.

Hypertonic Saline

• Mannitol and hypertonic saline are used together!!!

• Moves water out of brain tissue into the vascular system; useful in various conditions related to IICP.

  • Osmotic effect

  • Increased blood volume

  • Decreased ICP

• Uses: ICP, TBI, stroke, brain tumors, post-surgical brain swelling, cerebral edema, hydrocephalus with elevated ICP.

• Usually given IV

• Monitor for fluid overload, hypernatremia, and cardiac issues.

• Monitor: Monitor sodium levels- hypernatremia (seizures, confusion, coma) , monitor fluid status ( pulmonary edema, lung sounds, 02 level) , overcorrection of ICP (hypoperfusion). Monitor vital signs BP/HR mainly. Monitor urine output!

• S/E: Hypernatremia, pulmonary edema, cardiovascular problems, renal issues, thrombophlebitis.

Dexamethasone

• Glucocorticoid (steroid) reducing inflammation and cerebral edema in conditions that lead to increased ICP,

• Adverse Effects: Psychosis, weight gain, hyperglycemia.

Acetaminophen

• Used for pain relief and has antipyretic properties with lower bleeding risk than NSAIDs.

• Adverse Effects: Risk of hepatotoxicity; antidote is acetylcysteine.

Hydrocephalus

Non-communicating Hydrocephalus

• Causes: Congenital chiari malformation, acquired from meningitis, TBI, tumors.

• Characterized by blockage preventing CSF drainage leading to ventricular enlargement.

• Clinical Manifestations: Increased head circumference (infants), signs of IICP.

• Treatment: Requires shunt placement (VP or VA) with careful monitoring for complications such as infection.

Head Injury Overview

• Types of Injury:

  • Primary injury: immediate damage.

  • Secondary injury: downstream consequences such as hypoxia or increases in ICP.

Scalp and Brain Injuries

• Acute Care Needs:

  • Monitor for signs of IICP, support for familial distress, seizure precautions, behavioral safety/education.

  • Consider cranial surgery for severe cases over time.

Brain Tumors

• Incidence varies by demographics; diagnosis through CT, PET Scan, and biopsy.

• Primary tumors arise from brain tissues; secondary from systemic cancers.

• Treatment options include steroids, anticonvulsants, and surgery.

Inflammatory Disorders

Bacterial Meningitis

• Acute inflammation of meningeal tissues; high-risk populations include newborns and elderly.

• Etiology: Streptococcus pneumoniae, Neisseria meningitidis (vaccine-preventable).

• Identified through lumbar puncture, showing cloudy CSF, increased WBC, and decreased glucose.

Viral Meningitis and Encephalitis

• Etiology: Various viruses, symptoms include H/A, fever, and neck stiffness.

• CSF analysis shows a predominance of lymphocytes. Supportive care is critical, with antiviral options if indicated.

Reye’s Syndrome

• A rare but severe condition following viral infections in children post-aspirin use, characterized by acute encephalopathy and a high mortality rate due to cerebral edema and metabolic derangements.