ICP Treatment, EVD Management, and Brain Death

Vocabulary practice flashcards covering intracranial pressure (ICP) management, external ventricular drain (EVD) maintenance, clinical brain-death testing, and critical neurological care concepts.

Ventriculostomy / EVD

An invasive intracranial monitoring device capable of both continuously measuring intracranial pressure (ICP) and draining cerebrospinal fluid (CSF).

Subdural and Intraparenchymal Monitors

Types of intracranial pressure monitoring catheters that lack the diagnostic and therapeutic ability to drain cerebrospinal fluid (CSF).

Foramen of Monro

The internal anatomical landmark used for leveling an external ventricular drain (EVD) transducer and drip chamber, externally referenced at the tragus of the ear.

EVD Infection Prevention Protocol

The rigorous maintenance of strict sterile and aseptic technique during all dressing changes, access port entries, and line manipulations to prevent ventriculitis and meningitis.

EVD Output Monitoring Parameters

The systematic clinical tracking of cerebrospinal fluid drainage volume, visual appearance, temporal trends, and adherence to prescribed drainage/pressure orders.

EVD Movement Precaution

The safety requirement to turn the EVD stopcock off to drainage during patient turning, mobilization, or transport, followed by anatomical releveling before resuming drainage.

Improper EVD Height

An incorrect elevation of the drainage system that disrupts intracranial dynamics by allowing either excessive or insufficient cerebrospinal fluid removal.

Brain-Death Evaluation Triggers

The clinical presentation consisting of irreversible coma, complete absence of brainstem reflexes, and absent spontaneous respirations following the exclusion of reversible confounders.

Apnea Testing

A formal diagnostic protocol assessing the medullary respiratory center by determining if spontaneous breathing effort occurs in response to an adequate $CO_2$ stimulus.

Brain-Death Confounders

Reversible physiologic and pharmacological conditions that must be ruled out prior to testing, including hypothermia, sedatives, toxins, and neuromuscular paralysis.

Institutional Brain-Death Policy

Facility-specific protocols that define legal criteria and mandatory diagnostic tests, acknowledging that practices like EEG confirmation or dual-physician examination are not universal.

Rapid CSF Siphoning

The rapid, gravity-driven drainage of fluid that occurs when an EVD is left unclamped during movement, risking acute ventricular collapse and catastrophic tissue shifts.

Rejection of Bundled Care

The contraindication of clustering or bundling nursing care activities in severe intracranial hypertension, because continuous noxious sensory stimulation drives ICP to dangerous levels.

Low-Stimulus Environment

An environmental modification strategy that dims room lighting, maintains quiet surroundings, and restricts bedside conversations to prevent sensory triggers in elevated ICP.

Hypertonic Saline Infusions

Hyperosmolar intravenous solutions that generate an intravascular osmotic gradient, drawing interstitial fluid across an intact blood-brain barrier out of cerebral parenchyma into the vascular space.

Mannitol

An intravenous osmotic diuretic that expands plasma volume and shifts excess fluid from the cerebral parenchyma into the intravascular compartment for renal excretion.

Indwelling Urinary Foley Catheter

A mandatory nursing requirement during mannitol therapy used to track rapid, high-volume diuresis and evaluate the effectiveness of osmotic therapy.

Hemicraniectomy

A surgical decompression procedure involving the removal of a large cranial skull bone flap and opening of the dura, permitting the edematous brain to expand outward.

Refractory ICP Pathophysiological Endpoint

Sustained, untreatable intracranial hypertension that obliterates cerebral microvasculature, halts cerebral blood flow, and causes global neuronal necrosis with cessation of all brain and brainstem function.

Positive Apnea Test Criteria

The confirmation of brain death during apnea testing when arterial carbon dioxide tension reaches PaCO_2 \blank \text{criteria} of \blank \text{or} \blank: a level of \blank \text{value} or higher, specifically defined as $\ge 60\,\text{mmHg}$ (or $\ge 20\,\text{mmHg}$ over baseline) without spontaneous respiratory effort.

Normal Adult Supine ICP

The resting intracranial pressure range in a supine adult, cited as approximately $5\text{--}15\,\text{mm\,Hg}$ in ATI materials and $5\text{--}10\,\text{mm\,Hg}$ in course notes.

Prolonged Elevated ICP Threshold

A sustained intracranial pressure measurement greater than $20\,\text{mm\,Hg}$, which is clinically linked to worsening patient outcomes.

Optimal Cerebral Perfusion Pressure (CPP)

The recommended target range for cerebral blood perfusion described by the ATI text as generally $60\text{--}70\,\text{mm\,Hg}$.

Brain Volume ICP Causes

Mechanisms that increase intracranial pressure by enlarging the tissue volume of the brain, including cerebral edema, hemorrhage, tumor, abscess, or tissue infarction.

CSF Volume ICP Causes

Factors increasing intracranial pressure via the fluid compartment, including hydrocephalus, choroid plexus tumors, hypersecretion of CSF, or meningeal inflammation.

Blood Volume ICP Causes

Hemodynamic causes of elevated intracranial pressure, such as augmented cerebral arterial inflow, impaired venous drainage, or raised central venous pressure.

Early Enteral Nutrition Priority

The clinical recommendation to initiate enteral feeding within $24\text{--}48\,\text{hours}$ when safe in high-risk, critically ill neurological patients.

Ebb Phase

The initial post-injury physiological phase in severe neurologic illness characterized predominantly by hemodynamic instability.

Flow Phase

The secondary post-injury physiological phase characterized by prolonged catabolic metabolism, muscle breakdown, and ongoing metabolic instability.

Psychosocial Consequences of Neurologic Injury

Secondary neurobehavioral impairments involving social cognition, impulse management, emotional mood, self-motivation, and personal relationships.

Early Signs of Increasing ICP

Initial indicators of worsening cranial pressure, including headache, nausea or vomiting, confusion, photophobia, and blurred or double vision.

Late Signs of Increasing ICP

Advanced indications of severe intracranial hypertension, including non-reactive or dilated pupils, respiratory compromise, motor posturing, coma, and Cushing triad.

Cushing Triad

A classic clinical sign of dangerously elevated intracranial pressure comprising a widening pulse pressure, bradycardia, and irregular/abnormal respirations.

Decorticate Posturing

An abnormal motor response presenting as rigid flexion of the upper extremities pulled inward toward the chest combined with extended lower extremities.

Decerebrate Posturing

An ominous motor finding marked by rigid extension and pronation of the upper extremities alongside full lower-extremity extension.

Glasgow Coma Scale (GCS) Ranges

A neurological assessment scored from $3$ to $15$, stratified into mild head injury ($13\text{--}15$), moderate injury ($9\text{--}12$), and severe brain injury ($< 9$).

Noninvasive ICP Estimation Tools

Bedside noninvasive modalities, specifically transcranial Doppler and optic nerve sheath ultrasonography, which provide pressure estimations without replacing direct invasive monitors.

Optic Nerve Sheath Ultrasound Contraindication

Physical ocular trauma, specifically the presence of an open-globe injury, which precludes applying transducer pressure over the orbit.

Suspected High ICP Nursing Reassessment

A targeted clinical evaluation prioritizing airway and ventilation, conscious awareness/GCS, pupillary reactions, motor function, vital signs, systemic perfusion, and seizure activity.

ICP-Reducing Patient Positioning

Positioning the client with the head of the bed elevated to at least $30^\circ$ while keeping the head and neck strictly in a midline alignment.

Suctioning and Positioning Precaution

The clinical principle that airway suction and bed adjustments temporarily spike ICP, necessitating that they be performed only when clearly indicated while monitoring physiological response.

Increased ICP Medication Categories

The therapeutic pharmaceutical classes used in management: hyperosmolar solutions, anticonvulsants, sedatives/analgesics, and salvage therapies for refractory hypertension.

Propofol and Fentanyl

Intravenous sedative and opioid analgesic agents administered to ventilated neurological patients to minimize motor agitation and optimize ventilator synchrony.

Pentobarbital

A barbiturate medication utilized under continuous intensive monitoring for refractory intracranial hypertension to profoundly suppress cerebral metabolic activity.

Neuromuscular Blockers

Paralytic agents restricted from routine use and reserved exclusively for severe shivering, profound agitation, or refractory ventilator dyssynchrony.

Mannitol Monitoring Requirements

Mandatory surveillance parameters during hyperosmolar therapy, including hourly urine output, cumulative fluid balance, serum electrolyte levels, renal function tests, and ICP trend.

Declining LOC Priority Action

The immediate clinical priority to secure and protect the airway while urgently reassessing the patient for impending cerebral herniation or acute structural decline.

Interprofessional Neurologic Recovery Disciplines

The comprehensive healthcare team comprising nursing, medicine, respiratory therapy, PT, OT, speech-language pathology (SLP), clinical nutrition, and specialized rehabilitation services.