extracellular fluid includes

ATI RN

ATI Fluid and Electrolytes

1. Extracellular fluid includes:

A. plasma and intracellular fluid.
B. interstitial and intracellular fluids.
C. plasma and interstitial fluid.
D. plasma, interstitial fluid, and intracellular fluid.

Correct answer: C

Rationale: The correct answer is C: 'plasma and interstitial fluid.' Extracellular fluid consists of all body fluids outside the cells, primarily including plasma (the liquid component of blood) and interstitial fluid (the fluid between cells). Choices A, B, and D are incorrect because intracellular fluid is located within the cells, not in the extracellular fluid compartment.

2. 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.

3. You are performing an admission assessment on an older adult patient newly admitted for end-stage liver disease. What principle should guide your assessment of the patient's skin turgor?

A. Overhydration is common among healthy older adults.
B. Dehydration causes the skin to appear spongy.
C. Inelastic skin turgor is a normal part of aging.
D. Skin turgor cannot be assessed in patients over 70.

Correct answer: C

Rationale: Inelastic skin is a normal change of aging. However, this does not mean that skin turgor cannot be assessed in older patients. Dehydration, not overhydration, causes inelastic skin with tenting. Overhydration, not dehydration, causes the skin to appear edematous and spongy. Choice A is incorrect because overhydration is not common among healthy older adults. Choice B is incorrect because dehydration leads to inelastic skin, not sponginess. Choice D is incorrect as skin turgor assessment can be done in patients of any age, including those over 70.

4. A nurse sees a variety of patients in the community health clinic. Which of the following patients would be at the greatest risk of dehydration?

A. An 18-year-old basketball player with a stress fracture of the right foot
B. An infant with diarrhea
C. A 45-year-old with stomach flu
D. An elderly patient living alone

Correct answer: B

Rationale: The correct answer is B. Infants are particularly vulnerable to dehydration due to diarrhea because they have a higher fluid turnover and less reserve. Option A, the 18-year-old basketball player with a stress fracture, is less likely to be at the greatest risk of dehydration compared to an infant with diarrhea. Option C, the 45-year-old with stomach flu, may experience dehydration but is not at the same level of risk as an infant with diarrhea. Option D, the elderly patient living alone, could be at risk of dehydration, but infants with diarrhea are at the greatest risk due to their unique physiological characteristics.

5. What is the function of aldosterone?

A. Regulates body temperature.
B. Decreases blood pressure.
C. Increases sodium reabsorption.
D. Promotes water excretion.

Correct answer: C

Rationale: Aldosterone increases the reabsorption of sodium in the kidneys, which leads to an increase in blood volume and blood pressure. Choice A is incorrect as aldosterone does not regulate body temperature. Choice B is incorrect as aldosterone increases blood pressure by increasing sodium reabsorption. Choice D is incorrect as aldosterone promotes water retention by increasing sodium reabsorption.