NCLEX-RN Study Guide

NCLEX Renal and Genitourinary Questions (2026)

November 2, 2026 · 5 min read

Short answer. Renal NCLEX questions connect a falling urine output to a rising potassium and ask you to act before the heart is affected. Monitoring intake and output is the assessment, and protecting the heart is the priority.

What the 2026 NCLEX tests in this area

Physiological Adaptation: acute kidney injury, chronic kidney disease, electrolyte consequences
Reduction of Risk Potential: dialysis access, lab monitoring, fluid restriction

Key facts to know

Normal urine output, adult	At least 30 mL per hour
Normal serum creatinine	0.6 to 1.2 mg/dL
Normal BUN	7 to 20 mg/dL
Dangerous potassium	Above 5.0 mEq/L, with cardiac risk rising above 6.0
Dialysis access precaution	No blood pressure or venipuncture on the arm with the fistula or graft
First sign of fluid overload on dialysis	Weight gain, dyspnea, crackles and edema between treatments

Practice question from this chapter

A client with prerenal acute kidney injury from dehydration is receiving intravenous fluids. The urine output has increased from 10 mL/hour to 35 mL/hour, the blood pressure is 108/68 mmHg, and the creatinine is trending down. Which evaluation is correct?

The kidneys are failing and dialysis is needed immediately
The fluid replacement is effective because urine output is improving
The creatinine trend indicates the intravenous fluids should be stopped
The blood pressure is too low and the fluids should be restricted

Show answer and rationale

Correct answer: B. The fluid replacement is effective because urine output is improving

Calling the fluid replacement effective is correct because rising urine output with a stable blood pressure and falling creatinine shows renal perfusion is being restored. Dialysis is not indicated with improving renal function, stopping fluids would reverse the gains, and 108/68 mmHg with improving output does not warrant restriction.

Second practice question

A client is 2 days after a nephrectomy. Morning laboratory results: serum creatinine increased from 1.2 to 1.9 mg/dL, serum potassium 5.6 mEq/L, and urine output 30 mL per hour. Which finding warrants immediate notification of the provider?

Serum creatinine increased from 1.2 to 1.9 mg/dL
Urine output 30 mL per hour
Serum potassium 5.6 mEq/L
Mild tenderness at the incision site

Show answer and rationale

Correct answer: D. Mild tenderness at the incision site

The correct option is the potassium level because hyperkalemia at 5.6 mEq/L creates an immediate risk of life-threatening dysrhythmias in a client with a single remaining kidney. The creatinine rise is important and should be reported, but it is not the immediate arrhythmia threat. Urine output of 30 mL per hour is low-normal and needs monitoring rather than urgent notification. Mild incisional tenderness is an expected postoperative finding and is not urgent.

Oliguria as a warning

A urine output below 30 mL per hour for two consecutive hours is the number that starts the renal item. Your next step is not a diuretic, it is a fluid challenge assessment: check for obstruction, review recent nephrotoxins, and look at the trend rather than the single hour. A client who is dry needs volume, a client who is overloaded needs restriction, and the item always gives you enough to tell them apart.

Hyperkalemia is the emergency hiding inside kidney failure. Tall peaked T waves on the monitor mean the potassium is already dangerous, and the treatment order matters more than the number on the lab report.

Dialysis items

Protect the access first. That means no blood pressure cuff, no blood draws and no intravenous lines in the fistula arm. Before a session, assess the thrill and bruit. After a session, expect weight loss and watch for hypotension and bleeding from the access site.

Follow the numbers in order

Renal items reward a sequence: urine output, then creatinine and blood urea nitrogen, then potassium, then acid base. Output falls first, the labs follow hours later, and potassium becomes dangerous before the client looks unwell.

Prerenal, intrarenal and postrenal causes each get a different first action. Prerenal means restore volume, intrarenal means stop the insult such as a nephrotoxic drug, and postrenal means relieve the obstruction. The stem almost always hands you the clue: dehydration, an aminoglycoside, or difficulty passing urine.

Dialysis items and the access rule

Protect the fistula arm at all times. No blood pressure cuff, no venipuncture, no intravenous line, and no sleeping on that side. Before treatment assess the thrill and the bruit, and after treatment expect weight loss and watch for hypotension and access site bleeding.

Between treatments the item is usually about fluid. Daily weight is the most reliable measure, and a gain of more than about one kilogram per day signals overload.

Frequently asked questions

What is the first sign of acute kidney injury?

A falling urine output, often before creatinine rises. Monitor hourly output and report less than 30 mL per hour for two hours.

Why is potassium dangerous in kidney failure?

The kidneys excrete potassium, so it accumulates. Hyperkalemia causes peaked T waves and can progress to lethal dysrhythmias.

Which arm do I avoid in a dialysis client?

The arm with the arteriovenous fistula or graft. No blood pressure, no venipuncture, no intravenous access on that side.

How do I tell dehydration from fluid overload?

Weight change, skin turgor, mucous membranes, lung sounds and jugular venous pressure together. One sign alone is not enough.

What is the first sign of fluid overload in a dialysis client?

Weight gain, then dyspnoea and crackles. Daily weight is the earliest reliable indicator because it changes before the lungs sound wet.

Which potassium level needs immediate action?

Above 5.5 mEq/L, and above 6.0 with ECG changes such as peaked T waves. Expect calcium, insulin with glucose, and dialysis for refractory cases.

Practise this chapter with rationales

NCLEXDeck gives you practice questions for every body system, with a rationale for the correct answer and for each distractor. Start on the free tier, no card required.

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