a patient with diabetes insipidus is admitted to the intensive care unit after a motor vehicle accident that resulted in head trauma and damage to the

ATI RN

Fluid and Electrolytes ATI

1. A patient with diabetes insipidus is admitted to the intensive care unit after a motor vehicle accident that resulted in head trauma and damage to the pituitary gland. Diabetes insipidus can occur when there is a decreased production of which of the following?

A. ADH
B. Estrogen
C. Aldosterone
D. Renin

Correct answer: A

Rationale: The correct answer is A: ADH. Diabetes insipidus is characterized by a deficiency in antidiuretic hormone (ADH), leading to excessive urine output and thirst. In this scenario, the head trauma and damage to the pituitary gland can result in decreased production or release of ADH. Estrogen (Choice B) is not directly related to diabetes insipidus. Aldosterone (Choice C) is a hormone that regulates sodium and potassium levels, not water balance like ADH. Renin (Choice D) is an enzyme involved in the regulation of blood pressure and fluid balance but not directly related to diabetes insipidus.

2. 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.

3. Which condition can result from prolonged vomiting or diarrhea?

A. Intracellular fluid
B. Interstitial fluid
C. Dehydration
D. Electrolyte

Correct answer: C

Rationale: The correct answer is C: Dehydration. Prolonged vomiting or diarrhea can lead to significant fluid loss, causing dehydration. Intracellular fluid (choice A) and interstitial fluid (choice B) refer to specific compartments of body fluid and are not conditions resulting from vomiting or diarrhea. Electrolytes (choice D) are minerals that help maintain fluid balance in the body but are not the condition directly resulting from prolonged vomiting or diarrhea.

4. The nurse is caring for a postthyroidectomy patient at risk for hypocalcemia. What action should the nurse take when assessing for hypocalcemia?

A. Monitor laboratory values daily for an elevated thyroid-stimulating hormone.
B. Observe for swelling of the neck, tracheal deviation, and severe pain.
C. Evaluate the quality of the patient's voice postoperatively, noting any drastic changes.
D. Observe for muscle twitching and numbness or tingling of the lips, fingers, and toes.

Correct answer: D

Rationale: Muscle twitching and numbness or tingling of the lips, fingers, and toes are signs of hyperirritability of the nervous system due to hypocalcemia. The other options describe complications the nurse should also be observing for; however, tetany and neurologic alterations are primary indications of hypocalcemia. Monitoring for an elevated thyroid-stimulating hormone (choice A) is not relevant in assessing for hypocalcemia. Observing for swelling of the neck, tracheal deviation, and severe pain (choice B) are more related to airway compromise. Evaluating the quality of the patient's voice postoperatively (choice C) is important but not a primary sign of hypocalcemia.

5. 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.