A nurse is assessing a patient with a suspected brain injury… | 마이메르시 MyMerci
Adult Health
문제

A nurse is assessing a patient with a suspected brain injury. Which assessment finding would indicate increased intracranial pressure (ICP)?

해설
Cushing's triad (bradycardia, widening pulse pressure, irregular respirations) is a classic late sign of increased ICP. Other options represent normal or non-specific findings not indicative of elevated ICP.

심화 해설

Core Nursing Explanation This question tests the ability to recognize the classic late signs of Increased Intracranial Pressure (ICP). The brain is enclosed within the rigid skull. When pressure inside this compartment rises, it can lead to life-threatening brain herniation. The body's final compensatory mechanisms to maintain cerebral perfusion pressure (CPP) manifest as a specific set of vital sign changes. Key Concept Analysis The core concept is the Monro-Kellie Doctrine. The skull is a fixed volume containing brain tissue, blood, and cerebrospinal fluid (CSF). An increase in the volume of any one component (e.g., from a tumor, hemorrhage, or edema) must be compensated for by a decrease in another, or ICP will rise. When these compensatory mechanisms fail, ICP increases, leading to Cerebral ischemia and potential herniation. Answer Rationale Key Point! The correct answer describes Cushing's Triad (or Cushing's Response), a classic and ominous sign of severely elevated ICP and impending brain herniation. It consists of: 1. Bradycardia: Caused by pressure on the vagal nerve center in the medulla oblongata. 2. Widening Pulse Pressure (Systolic BP rises while diastolic BP remains stable or falls): This is a compensatory mechanism. The body increases systemic vascular resistance (raises systolic BP) to force blood into the brain against the high ICP, attempting to maintain Cerebral Perfusion Pressure (CPP = MAP - ICP). 3. Irregular Respirations (Cheyne-Stokes, ataxic breathing): Caused by direct pressure on or ischemia of the respiratory centers in the brainstem. Distractor Analysis Watch out for confusion! The incorrect options represent normal or early findings, not the specific signs of dangerously high ICP. • Option 1: Represents normal, stable vital signs. In early increased ICP, the body compensates, and vital signs may remain normal. • Option 2: Describes a normal level of consciousness (LOC). A change in LOC (e.g., restlessness, confusion, lethargy, coma) is often the earliest and most sensitive sign of increasing ICP, not a normal, alert state. • Option 3: Describes normal pupillary response (PERRLA). Pupillary changes (unequal size, sluggish or absent reaction to light) are critical signs of increased ICP and brainstem compression but are not part of Cushing's Triad. Fixed and dilated pupils are a late, pre-terminal sign. Related Concepts Nurses must monitor for a progression of signs: Early signs include headache, vomiting, and decreased LOC. Later signs include motor changes (decorticate or decerebrate posturing) and pupillary abnormalities. Cushing's Triad is a very late sign indicating that compensatory mechanisms are failing.
Concept SummaryIncreased ICP: Pressure > 15 mmHg (normal: 5-15 mmHg). • Early Signs: Change in LOC (most sensitive), headache, projectile vomiting, vision changes. • Late Signs (Cushing's Triad): Bradycardia, Widening Pulse Pressure, Irregular Respirations. • Pre-terminal Signs: Fixed, dilated pupils; abnormal posturing; cessation of breathing.
Side-by-Side Comparison!
SignEarly Increased ICPLate Increased ICP (Cushing's Triad)
Level of Consciousness (LOC)Restlessness, confusion, lethargyComa
Vital SignsMay be normalBradycardia, Widening Pulse Pressure, Irregular Respirations
PupilsMay be normal or slightly sluggishUnequal, fixed and dilated
Motor ResponseMild weaknessDecorticate or decerebrate posturing, flaccidity

Anatomy, Physiology & Pharmacology PointsPathophysiology: The Monro-Kellie Doctrine explains the fixed volume of the cranial vault. Cerebral edema, hemorrhage, or tumor increases volume, leading to increased ICP and reduced cerebral blood flow. • Key Calculation: Cerebral Perfusion Pressure (CPP) = Mean Arterial Pressure (MAP) - Intracranial Pressure (ICP). Goal CPP is > 60-70 mmHg. • Common Medications: Mannitol (osmotic diuretic), Hypertonic saline (3%), and corticosteroids (e.g., Dexamethasone) are used to reduce cerebral edema and ICP.
Memory TipsFor Cushing's Triad: Remember "Bradycardia, Widening BP, Irregular Breathing" → "Brain Warning: Imminent Crisis!" • For Early Signs: "Headache, Vomiting, Change in LOC" → "High Volume Crushing the brain."
High-Frequency NCLEX Topics Increased ICP is a High Yield topic. The NCLEX loves to test: 1. Identifying Cushing's Triad as a late sign. 2. Prioritizing nursing actions for a patient with increased ICP (e.g., maintaining head of bed elevation, avoiding activities that increase ICP like coughing or straining). 3. Recognizing that a change in LOC is the earliest and most important sign to report.
Watch Out for Question Variations! • Instead of asking for the sign, it may ask: "Which finding requires immediate intervention?" (Answer: Cushing's Triad). • It may present a scenario with early signs (headache, vomiting) and ask for the priority nursing assessment (Answer: Neurological check, including LOC). • It may combine with medication administration: "The nurse is administering Mannitol. Which finding indicates the medication is effective?" (Answer: Decreased ICP readings or improved neurological status).

임상 시나리오

Nursing Clinical Practice Guide Clinical Scenario You are the nurse for Mr. Johnson, a 68-year-old male admitted after a fall with a subdural hematoma. He was initially alert but is now difficult to arouse. His vital signs two hours ago were BP 150/90, HR 92, RR 18. Your current assessment reveals: BP 180/70, HR 52, RR 8 and irregular (Cheyne-Stokes pattern). His right pupil is 5mm and sluggish to light; left pupil is 3mm and reactive. Nursing Intervention Strategy 1. Immediate Action (ABCs): Ensure a patent airway. Anticipate the need for intubation due to irregular respirations. Call a rapid response or alert the provider STAT. 2. Positioning: Elevate the head of the bed to 30 degrees with the head in a neutral, midline position to promote venous drainage from the brain. 3. Minimize ICP Increases: Cluster nursing care to provide rest periods. Avoid activities that cause Valsalva maneuvers (straining, coughing). Administer stool softeners. Provide quiet, calm environment. 4. Monitoring: Continuous monitoring of vital signs, pulse oximetry, and neurological status (Glasgow Coma Scale - GCS) every 15 minutes or more frequently. Document pupillary checks meticulously. Patient Safety and PrecautionsContraindications: Do not lower the head of the bed. Avoid hip flexion > 90 degrees. Do not suction via the nares if a basilar skull fracture is suspected. • Medication Cautions: When giving osmotic diuretics like Mannitol, monitor for electrolyte imbalances (especially hypernatremia, hypokalemia) and renal function. Ensure IV access is patent to prevent tissue necrosis if it infiltrates.
Nursing Procedure & Medication Flow Neurological Assessment (Neuro Check): 1. Level of Consciousness: Use the Glasgow Coma Scale (GCS). Assess Eye opening (E), Verbal response (V), Motor response (M). A decreasing score indicates deterioration. 2. Pupillary Response: Check size (in mm), shape, equality, and reaction to light (direct and consensual). Use a penlight. 3. Motor Function: Assess strength and symmetry in all extremities. Command: "Squeeze my fingers," "Push down with your feet," "Lift your leg off the bed." 4. Vital Signs: Note trends, especially widening pulse pressure and bradycardia. Mannitol Administration: • Action: Osmotic diuretic that draws fluid from brain tissue into the vasculature, reducing cerebral edema. • Dose & Route: Given IV via a large-bore catheter, often as a bolus (e.g., 0.25-1 g/kg of a 20% solution). • Monitoring: Strict I&O (Intake and Output). Monitor for signs of dehydration and electrolyte shifts. Watch for rebound increased ICP.
A Word from Your Senior Nurse "Brain injuries are a race against time. Cushing's Triad is the body's final, desperate alarm bell. In clinical practice, you won't often see the full triad in a stable patient—it's an emergency. Your most powerful tool is your ongoing, meticulous neurological assessment. Catching that subtle shift from 'oriented x3' to 'oriented x2' or that slight pupillary sluggishness is what saves lives. On the NCLEX, they test your knowledge of these classic signs to ensure you recognize a crisis. In real life, that knowledge, combined with sharp assessment skills, makes you the patient's guardian at the bedside."

핵심 개념

마이메르시로 국가고시 완벽 대비

기출문제와 상세 해설을 무료로. 내 약점을 분석하고 진도를 관리하며 더 똑똑하게 공부하세요.

무료로 시작하기

학습 참고용입니다. 실제 임상은 최신 지침과 소속 기관 프로토콜을 따르세요.