Lecture Notes: Increased Intracranial Pressure (ICP)

Overview

• Presenter: Sarah from RegisteredNurseAriene.com
• Topic: Increased intracranial pressure as part of NCLEX neurosystem review series.
• Quiz: Free quiz available to test knowledge on the condition.

What is Increased Intracranial Pressure?

• Definition: Pressure within the skull increases dramatically; a medical emergency as it can lead to brain death.
• Creation: Pressure created by cerebral spinal fluid (CSF), brain tissue, and blood.
• Measurement: Devices placed in the lateral ventricle or subarachnoid space to monitor pressure.
• Normal ICP: 5-15 mmHg; >20 mmHg requires immediate treatment.

Anatomy and Physiology

• Human Skull: Hard structure that limits expansion, leading to increased pressure.
• Key Structures: Brain, CSF, and blood.
• Monroe-Kelly Hypothesis: Describes compensation mechanisms among brain structures.

Influencing Factors

• Temperature: Hyperthermia increases ICP.
• Oxygenation: Hypoxia or high CO2 levels cause vasodilation, increasing ICP.
• Body Position: Important to align the body correctly to avoid increased ICP.
• Arterial/Venous Pressure: Increased intra-abdominal and thoracic pressure affect ICP.

Compensation Mechanisms

• Monroe-Kelly Hypothesis: Describes how CSF, blood, and brain tissue compensate for pressure changes.
• Cerebral Perfusion Pressure (CPP): Pressure pushing blood to the brain, normal 60-100 mmHg.
• Formula: CPP = MAP (Mean Arterial Pressure) - ICP.

Conditions Causing Increased ICP

• Head Trauma: Traumatic brain injury can lead to increased ICP.
• CSF Increase: Conditions like hydrocephalus can increase CSF volume.
• Bleeding/Hemorrhage: Hematomas can cause increased pressure.
• Tumors/Infections: Meningitis and encephalitis may increase ICP.

Pathophysiology and Recognition

• Blood Supply Cut-off: Leads to ischemia, decreased CPP, and decreased cerebral blood flow.
• Compensation Attempts: Body increases systolic BP, leading to further complications.
• Signs and Symptoms: Recognized using mnemonic "MIND CRUSH".

Signs and Symptoms (MIND CRUSH Mnemonic)

• M: Mental status changes (early indicator)
• I: Irregular breathing (e.g., Cheyne-Stokes breathing)
• N: Nerve changes (optic and oculomotor)
• D: Decerebrate or decorticate posturing
• C: Cushing's triad (late sign)
• R: Reflex (positive Babinski)
• U: Unconsciousness in late stages
• S: Seizures
• H: Headache
• E: Emesis (vomiting)
• D: Deterioration of motor function

Nursing Interventions (PRESSURE Mnemonic)

• P: Positioning the patient correctly to promote blood return.
• R: Respiratory management to prevent hypoxia and hypercapnia.
• E: Elevated temperature management to avoid hyperthermia.
• S: System monitoring using tools like Glasgow Coma Scale.
• S: Straining activities to avoid (e.g., coughing, sneezing).
• U: Unconscious patient care (prevent skin breakdown, maintain nutrition).
• R: Prescription medications (e.g., barbiturates, vasopressors).
• E: Edema management with hyperosmotic drugs (e.g., Mannitol).

Medication and Management

• Barbiturates: Decrease brain metabolism and blood pressure.
• Vasopressors/Antihypertensives: Maintain adequate blood pressure.
• Anticonvulsants: Prevent seizures.
• Mannitol: Dehydrates the brain by pulling water into the blood.
• Corticosteroids: Help manage protein leakage and swelling.

Conclusion

• Review: Importance of recognizing and treating increased ICP.
• Quiz and Subscription: Encouragement to take the quiz and subscribe for more content.