Nursing Elites

1. A patient who is in renal failure partially loses the ability to regulate changes in pH because the kidneys:

• A. Regulate and reabsorb carbonic acid to change and maintain pH
• B. Buffer acids through electrolyte changes
• C. Regenerate and reabsorb bicarbonate to maintain a stable pH
• D. Combine carbonic acid and bicarbonate to maintain a stable pH

Correct answer: C

Rationale: The correct answer is C. In renal failure, the kidneys lose the ability to regulate pH by controlling bicarbonate levels in the extracellular fluid (ECF). The kidneys can regenerate and reabsorb bicarbonate ions to maintain a stable pH. Choices A, B, and D are incorrect because the kidneys do not primarily regulate or reabsorb carbonic acid, buffer acids through electrolyte changes, or combine carbonic acid and bicarbonate to maintain pH. The key function of the kidneys in maintaining pH balance lies in the control of bicarbonate levels.

2. A 73-year-old man who slipped on a small carpet in his home and fell on his hip is alert and oriented; PERRLA (pupils equally round and reactive to light and accommodation) is intact, and he has come by ambulance to the emergency department (ED). Heart rate elevated, he is anxious and thirsty. A Foley catheter is in place and 40mL of urine is present. The nurse's most likely explanation for the urine output is:

• A. The man urinated prior to his arrival in the ED and will probably not need to have the Foley catheter kept in place.
• B. The man has a brain injury, lacks ADH, and needs vasopressin.
• C. The man is in heart failure and is releasing atrial natriuretic peptide, which results in decreased urine output.
• D. He is having a sympathetic reaction, which has stimulated the renin-angiotensin-aldosterone system that results in diminished urine output.

Correct answer: D

Rationale: Renin is released by the juxtaglomerular cells of the kidneys in response to decreased renal perfusion. Angiotensin-converting enzyme converts angiotensin I to angiotensin II. Angiotensin II, with its vasoconstrictor properties, increases arterial perfusion pressure and stimulates thirst. As the sympathetic nervous system is stimulated, aldosterone is released in response to an increased release of renin, which decreases urine production. Based on the nursing assessment and mechanism of injury, this is the most likely cause of the lower urine output. Choices A, B, and C are incorrect because there is no indication of urination prior to arrival, brain injury, lack of ADH, or heart failure present in the scenario provided. The symptoms and context described point more towards a physiological response related to the sympathetic nervous system and the renin-angiotensin-aldosterone system rather than the other conditions mentioned.

3. What fluid is found in spaces between the cells?

• A. Intracellular fluid
• B. Interstitial fluid
• C. Plasma
• D. Electrolyte

Correct answer: B

Rationale: The correct answer is B, Interstitial fluid. Interstitial fluid is the fluid that surrounds and occupies the spaces between cells, providing them with nutrients and removing waste. Choices A, C, and D are incorrect because intracellular fluid refers to fluid inside cells, plasma refers to the liquid component of blood, and electrolyte refers to substances that dissociate into ions in solution, affecting fluid balance but not specifically found in spaces between cells.

4. A client with a serum potassium of 7.5 mEq/L and cardiovascular changes needs immediate intervention. Which prescription should the nurse implement first?

• A. Prepare to administer sodium polystyrene sulfate (Kayexalate) 15 g by mouth.
• B. Provide a heart-healthy, low-potassium diet.
• C. Prepare to administer dextrose 20% and 10 units of regular insulin IV push.
• D. Prepare the client for hemodialysis treatment.

Correct answer: C

Rationale: In a client with a serum potassium level of 7.5 mEq/L and cardiovascular changes, the priority intervention is to lower the potassium level quickly to prevent life-threatening complications like arrhythmias. The correct answer is to prepare to administer dextrose 20% and 10 units of regular insulin IV push. This combination helps shift potassium from the extracellular to the intracellular space, reducing serum potassium levels rapidly. Administering sodium polystyrene sulfate (Kayexalate) by mouth may take several hours to work, making it a less effective immediate intervention. Providing a heart-healthy, low-potassium diet is important for long-term management but is not the most urgent action in this situation. While hemodialysis is a definitive treatment for hyperkalemia, it is not the first-line intervention for acute management of high potassium levels with cardiovascular manifestations.

5. What happens first in dehydration?

• A. Intercellular fluid volume drops first.
• B. Plasma volume drops first.
• C. Interstitial fluid drops first.
• D. Neither interstitial nor intracellular fluid volume are affected.

Correct answer: C

Rationale: In dehydration, the body first draws fluid from the interstitial space to maintain blood volume, leading to a decrease in interstitial fluid volume. This is why choice C is correct. Choice A is incorrect because intracellular fluid is not the first to be affected. Choice B is also incorrect as plasma volume reduction typically occurs after interstitial fluid loss. Choice D is incorrect as dehydration impacts both interstitial and intracellular fluid volumes.

Similar Questions