the most common positive ion in intracellular fluid is

ATI RN

ATI Fluid and Electrolytes

1. Which positive ion is most prevalent in intracellular fluid?

A. Calcium
B. Potassium
C. Sodium
D. Magnesium

Correct answer: B

Rationale: The correct answer is Potassium (K+). Potassium is the predominant cation found within cells, making it the most prevalent positive ion in intracellular fluid. Calcium, sodium, and magnesium are also essential ions in the body, but they are not as abundant in intracellular fluid. Calcium is vital for bone health and muscle function, sodium helps in maintaining fluid balance and nerve function, and magnesium is involved in numerous biochemical reactions.

2. The nurse in the medical ICU is caring for a patient who is in respiratory acidosis due to inadequate ventilation. What diagnosis could the patient have that could cause inadequate ventilation?

A. Endocarditis
B. Multiple myeloma
C. Guillain-Barr syndrome
D. Overdose of amphetamines

Correct answer: C

Rationale:

3. . A 73-year-old man comes into the emergency department (ED) by ambulance after slipping on a small carpet in his home. The patient fell on his hip with a resultant fracture. He is alert and oriented; his pupils are equal and reactive to light and accommodation. His heart rate is elevated, he is anxious and thirsty, a Foley catheter is placed, and 40 mL of urine is present. What is the nurses most likely explanation for the low urine output?

A. The man urinated prior to his arrival to the ED and will probably not need to have the Foley catheter kept in place.
B. The man likely has a traumatic brain injury, lacks antidiuretic hormone (ADH), and needs vasopressin.
C. The man is experiencing symptoms of heart failure and is releasing atrial natriuretic peptide that results in decreased urine output.
D. The man is having a sympathetic reaction, which has stimulated the reninangiotensinaldosterone system that results in diminished urine output.

Correct answer: D

Rationale:

4. Retention of electrolytes (especially sodium) in the interstitial fluid can result from:

A. decreased aldosterone secretion.
B. increased ADH secretion.
C. increased aldosterone secretion.
D. decreased ADH secretion.

Correct answer: C

Rationale: The correct answer is C: increased aldosterone secretion. Aldosterone, a hormone produced by the adrenal glands, increases sodium reabsorption in the kidneys, leading to retention of sodium and water in the interstitial fluid. Increased aldosterone secretion enhances the reabsorption of sodium, thereby increasing its retention. Choice A is incorrect because decreased aldosterone secretion would lead to less sodium reabsorption and increased excretion. Choice B is incorrect because increased ADH secretion primarily affects water reabsorption rather than sodium. Choice D is incorrect because decreased ADH secretion would lead to increased water excretion but not necessarily affect sodium retention.

5. Which hormone is made in the pituitary gland and increases water absorption in the kidney?

A. Intracellular fluid
B. Interstitial fluid
C. Plasma
D. ADH

Correct answer: D

Rationale: The correct answer is D, ADH (Antidiuretic hormone). ADH is produced by the pituitary gland and functions to increase water reabsorption in the kidneys. Choices A, B, and C are incorrect as they do not refer to a hormone responsible for increasing water absorption in the kidney.