ATI RN
ATI Fluid and Electrolytes
1. You are an emergency-room nurse caring for a trauma patient. Your patient has the following arterial blood gas results: pH 7.26, PaCO2 28, HCO3 11 mEq/L. How would you interpret these results?
- A. Respiratory acidosis with no compensation
- B. Metabolic alkalosis with a compensatory alkalosis
- C. Metabolic acidosis with no compensation
- D. Metabolic acidosis with a compensatory respiratory alkalosis
Correct answer: D
Rationale: A low pH indicates acidosis (normal pH is 7.35 to 7.45). The PaCO2 is also low, which causes alkalosis. The bicarbonate is low, which causes acidosis. The pH bicarbonate more closely corresponds with a decrease in pH, making the metabolic component the primary problem. Therefore, the correct interpretation of the arterial blood gas results is metabolic acidosis with a compensatory respiratory alkalosis. Choices A, B, and C are incorrect because they do not accurately reflect the primary acid-base disturbance and the compensatory response seen in the given results.
2. A nurse in the neurologic ICU has orders to infuse a hypertonic solution into a patient with increased intracranial pressure. This solution will increase the number of dissolved particles in the patient's blood, creating pressure for fluids in the tissues to shift into the capillaries and increase the blood volume. This process is best described as which of the following?
- A. Hydrostatic pressure
- B. Osmosis and osmolality
- C. Diffusion
- D. Active transport
Correct answer: B
Rationale: The correct answer is B: Osmosis and osmolality. Osmosis is the movement of fluid from a region of low solute concentration to a region of high solute concentration across a semipermeable membrane. In this case, the hypertonic solution increases the number of dissolved particles in the blood, causing fluids to shift into the capillaries due to the osmotic pressure gradient. Osmolality refers to the concentration of solutes in a solution. Hydrostatic pressure refers to changes in water or volume related to water pressure, not the movement of fluids due to solute concentration differences. Diffusion is the movement of solutes from an area of greater concentration to lesser concentration; in an intact vascular system, solutes are unable to move freely, so diffusion does not play a significant role in this scenario. Active transport involves the movement of molecules against the concentration gradient with the use of energy, typically at the cellular level, and is not related to the vascular volume changes described in the question.
3. 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.
4. Where is the largest volume of water in the body located?
- A. Plasma
- B. The fluid inside the cells
- C. Interstitial fluid
- D. Lymph
Correct answer: B
Rationale: The correct answer is B. The largest volume of water in the body is found inside the cells, known as intracellular fluid. This fluid makes up the majority of the body's total water content. Choices A, C, and D are incorrect because while plasma, interstitial fluid, and lymph are important components of the body's fluid compartments, they do not contain the largest volume of water in the body.
5. A nurse is caring for a patient who requires measurement of specific gravity every 4 hours. What does this test detect?
- A. Nutritional deficit
- B. Hyperkalemia
- C. Hypercalcemia
- D. Fluid volume status
Correct answer: D
Rationale: Specific gravity is a test used to determine the concentration of solutes in the urine, reflecting the kidney's ability to concentrate urine. Changes in specific gravity can indicate fluid volume status, such as dehydration (fluid volume deficit) or overhydration (fluid volume excess). Options A, B, and C are incorrect as specific gravity does not directly detect nutritional deficits, hyperkalemia, or hypercalcemia.
Similar Questions
Access More Features
ATI RN Basic
$69.99/ 30 days
- 50,000 Questions with answers
- All ATI courses Coverage
- 30 days access @ $69.99
ATI RN Premium
$149.99/ 90 days
- 50,000 Questions with answers
- All ATI courses Coverage
- 30 days access @ $149.99