A nurse is caring for a 65-year-old patient with acute kidney injury (AKI) in the oliguric phase, experiencing urine output of 200 mL in the past 24 hours. Laboratory results show: BUN 85 mg/dL, creatinine 4.2 mg/dL, potassium 6.8 mEq/L, and phosphorus 7.5 mg/dL. The patient appears restless and reports muscle weakness. Which nursing intervention should be the highest priority?
1Encourage increased fluid intake to promote kidney function
2Administer phosphate binders as prescribed
3Monitor for cardiac arrhythmias and prepare for emergency interventions✓ 정답
4Restrict protein intake to reduce nitrogenous waste
해설
With severe hyperkalemia (6.8 mEq/L) in oliguric AKI, monitoring for cardiac arrhythmias is the highest priority due to immediate life-threatening risk. Other interventions (phosphate binders, protein restriction) address less urgent complications.
Core Nursing ExplanationKey Concept Analysis: This question tests the nurse's ability to prioritize care for a patient with Acute Kidney Injury (AKI) in the oliguric phase, focusing on the most life-threatening complication. The core pathophysiology involves the kidney's inability to excrete waste products and regulate electrolytes, leading to dangerous imbalances. The patient's lab values reveal hyperkalemia (K+ 6.8 mEq/L) and hyperphosphatemia (Phos 7.5 mg/dL), along with symptoms of muscle weakness and restlessness, which are neurological signs of electrolyte disturbance.
Answer Rationale: Key Point! The highest priority is monitoring for cardiac arrhythmias. Hyperkalemia directly and dangerously affects cardiac muscle excitability. Elevated potassium levels (>5.5 mEq/L) can cause life-threatening arrhythmias such as ventricular tachycardia, ventricular fibrillation, or asystole. The patient's level of 6.8 mEq/L is severe and requires immediate cardiac monitoring and preparation for emergency interventions like calcium gluconate (to stabilize the cardiac membrane), insulin/glucose, sodium bicarbonate, or kayexalate. The symptom of muscle weakness is also a classic sign of hyperkalemia. In the nursing process, this falls under the Assessment and Implementation phases for a potential life-threatening situation, aligning with the ABCs (Airway, Breathing, Circulation) priority framework.
Distractor Analysis:
1. Watch out for confusion! Encouraging increased fluid intake is contraindicated in the oliguric phase of AKI. The kidneys cannot excrete the excess fluid, which could lead to fluid overload, hypertension, and pulmonary edema. Fluid management in oliguric AKI is typically restrictive.
2. Administering phosphate binders is a correct intervention for hyperphosphatemia, but it is not the highest priority. While hyperphosphatemia contributes to complications like pruritus and bone disease, it does not pose an immediate, direct threat to life like severe hyperkalemia does.
4. Restricting protein intake is a correct dietary management strategy to reduce the buildup of BUN (Blood Urea Nitrogen) and other nitrogenous wastes. However, this is a longer-term nutritional intervention and does not address the acute, life-threatening electrolyte emergency.
Related Concepts: The priority-setting principle here is Maslow's Hierarchy of Needs and the ABC (Airway, Breathing, Circulation) priority framework. Physiological needs (specifically, maintaining effective cardiac output and circulation) take precedence over other physiological or safety needs. This scenario also integrates knowledge of electrolyte imbalances, their effects on specific body systems (cardiac vs. neuromuscular), and the phases of AKI (oliguric, diuretic, recovery).
Concept Summary
Concept
Key Takeaway
Acute Kidney Injury (AKI) Oliguric Phase
Urine output <400 mL/24h. Kidneys fail to excrete waste, fluid, and electrolytes.
Hyperkalemia in AKI
Life-threatening complication. Priority is cardiac monitoring for arrhythmias. Emergency treatments include calcium, insulin/glucose, kayexalate.
Nursing Priorities (ABCs)
Airway, Breathing, Circulation first. An arrhythmia from hyperkalemia is a direct threat to Circulation.
Cardiac monitor, prepare emergency meds (Ca gluconate)
Hyperphosphatemia (High Phos)
>4.5 mg/dL
Long-term: bone disease, vascular calcification
Administer phosphate binders with meals
Hypercalcemia (High Ca2+)
>10.5 mg/dL
Cardiac arrest ("Stones, Bones, Groans, Moans")
Cardiac monitor, IV fluids, loop diuretics
Anatomy, Physiology & Pharmacology Points
Physiology: The kidneys regulate potassium via secretion in the distal tubule. In AKI, this mechanism fails, causing rapid potassium accumulation in the blood (hyperkalemia).
Pharmacology - Emergency Hyperkalemia Treatment:
Calcium Gluconate/Chloride: Does not lower potassium. Stabilizes the cardiac cell membrane to prevent arrhythmias. First-line for EKG changes.
Insulin + Glucose: Drives potassium from the blood into cells (temporary shift).
Sodium Bicarbonate: Alkalosis drives K+ into cells (especially useful if acidosis is present).
Kayexalate (Sodium Polystyrene Sulfonate): Binds potassium in the GI tract for excretion (definitive removal).
Memory Tips
HyperK = Heart Attack: Remember that HyperKalemia's biggest risk is to the Heart. "K" for "Kardiac" arrest.
AKI Oliguria Management: DR. HIP - This reminds you of key restrictions/interventions:
Diet (Protein & Potassium restriction)
Restrict Fluids
Hyperkalemia monitoring (Priority!)
Infection prevention
Phosphate binders
High-Frequency NCLEX Topics
This integrates several high-yield NCLEX areas: prioritization (ABCs), electrolyte imbalances, renal failure, and pharmacology for emergencies. The NCLEX loves to test if you can identify the most immediate threat to a patient's life from a list of correct interventions.
Watch Out for Question Variations!
Shift from Symptom to Intervention: The question might give you EKG findings (peaked T waves, widened QRS) instead of lab values and ask for the priority action.
Shift from AKI to Chronic Kidney Disease (CKD): In CKD, hyperkalemia is still dangerous, but hyperphosphatemia management is a chronic priority. The question might test if you know phosphate binders are taken with meals.
Medication Administration: A follow-up question could ask, "The nurse prepares to administer calcium gluconate for hyperkalemia. Which assessment is most critical before administration?" (Answer: Check the patient's digitalis (digoxin) level, as calcium can potentiate digoxin toxicity).
Nursing Clinical Practice GuideClinical Scenario: You are the nurse on a medical-surgical unit. Mr. Johnson, 65, was admitted with sepsis-induced AKI. His urine output has been minimal, and the latest labs show critical hyperkalemia. He is on a cardiac monitor, appears anxious, and complains his "arms and legs feel heavy."
Nursing Intervention Strategy:
Immediate Assessment (Circulation First):
Connect patient to continuous cardiac monitoring. Assess rhythm strip for peaked T waves, widened QRS, or loss of P waves.
Obtain a STAT 12-lead EKG as ordered.
Assess vital signs frequently (BP, HR, O2 sat).
Perform a focused neuro assessment (muscle strength, sensation, reflexes) related to hyperkalemia.
Prepare for Emergency Interventions:
Ensure IV access is patent.
Prepare emergency medications as per protocol/physician order: Calcium gluconate (usually 10 mL of 10% solution IV push over 2-5 minutes), regular insulin IV with D50W, sodium bicarbonate.
Have a defibrillator and emergency cart accessible.
Collaborate & Communicate:
Notify the physician/provider immediately with SBAR: "Situation: Mr. Johnson K+ is 6.8. Background: AKI, oliguric. Assessment: Restless, muscle weakness, rhythm shows peaked T waves. Recommendation: Request orders for calcium gluconate and other hyperkalemia treatments."
Consult renal/dialysis team if emergent dialysis is being considered.
Ongoing Management:
Implement strict potassium restriction (no bananas, oranges, potatoes, tomatoes).
Administer phosphate binders (e.g., calcium acetate) with meals as scheduled.
Monitor intake and output (I&O) meticulously.
Patient Safety and Precautions:
Medication Alert: Do NOT administer potassium-sparing diuretics, ACE inhibitors, or NSAIDs, as they can worsen hyperkalemia.
IV Calcium Administration: Administer slowly (over 2-5 mins) while monitoring the EKG. Infuse through a patent, large-bore IV to avoid tissue necrosis from infiltration. Contraindicated if hypercalcemia is suspected.
Insulin/Glucose: Monitor blood glucose closely every 30-60 minutes after administration to prevent hypoglycemia.
Kayexalate: Can cause constipation or bowel necrosis. Ensure patient has a bowel movement; monitor for abdominal pain.
Nursing Procedure & Medication FlowResponding to Critical Hyperkalemia (Sample Protocol):
1. Confirm: Verify lab result and assess patient/EKG.
2. Call: Alert rapid response team or physician.
3. Cardiac Protection: Administer Calcium Gluconate 1g IV over 2-5 minutes with EKG monitoring.
4. Shift Potassium: Administer Regular Insulin 10 units IV + 1 amp D50W.
5. Remove Potassium: Administer Kayexalate 30g PO/PR or prepare for dialysis.
6. Monitor: Repeat potassium level in 1-2 hours. Continue cardiac monitoring.
A Word from Your Senior Nurse
"In the chaos of a busy shift, lab results can sometimes feel like just numbers on a screen. But a potassium of 6.8 isn't just a number—it's a ticking time bomb for the heart. Your most important tool in this situation isn't the medication vial; it's your eyes on the cardiac monitor and your clinical judgment to act fast. Always think: 'What can kill my patient first?' In AKI, it's almost always the potassium affecting the heart or the fluid affecting the lungs. Mastering this prioritization will make you an invaluable nurse and save lives. Now, go ace that question and carry that confidence to the bedside!"
Acute Kidney Injury — Sudden loss of kidney function over hours to days, leading to accumulation of waste products and dysregulation of fluid/electrolytes.
Hyperkalemia — A serum potassium level >5.5 mEq/L. A medical emergency due to its effect on cardiac muscle excitability, potentially causing lethal arrhythmias.
Oliguria — Reduced urine output, typically defined as <400 mL in 24 hours. A hallmark of the oliguric phase of AKI.
Phosphate Binders — Medications (e.g., calcium acetate, sevelamer) that bind dietary phosphate in the GI tract to prevent its absorption. Administered with meals.
Cardiac Arrhythmia — Any abnormality in the rate, rhythm, or conduction of the heart's electrical activity. A critical complication of severe electrolyte imbalances like hyperkalemia.