which electrolyte is important in the formation of the thyroid hormones

ATI RN

ATI Fluid and Electrolytes

1. Which electrolyte is important in the formation of the thyroid hormones?

A. Sodium
B. Iodine
C. Iron
D. Chloride

Correct answer: B

Rationale: Iodine is the correct answer because it is essential for the synthesis of thyroid hormones. The thyroid gland incorporates iodine into thyroid hormones such as thyroxine (T4) and triiodothyronine (T3). These hormones are crucial for regulating metabolism, growth, and development. Sodium, iron, and chloride are not directly involved in the formation of thyroid hormones, making them incorrect choices.

2. When considering overhydration:

A. occurs less often than dehydration.
B. can strain the kidneys.
C. can be caused by giving intravenous fluids too rapidly.
D. less common than dehydration.

Correct answer: C

Rationale: The correct answer is C. Overhydration can occur when intravenous fluids are administered too quickly, overwhelming the body's ability to excrete the excess fluid. Choices A, B, and D are incorrect. Choice A is incorrect because overhydration is less common than dehydration. Choice B is incorrect because while overhydration can strain the kidneys, it is not due to the burden being too heavy. Choice D is incorrect because dehydration is more common than overhydration.

3. The nurse in the intensive care unit receives arterial blood gases (ABG) with a patient who is complaining of being 'short of breath.' The ABG has the following values: pH = 7.21, PaCO2 = 64 mm Hg, HCO3 = 24 mmol/L. The labs reflect:

A. Respiratory acidosis
B. Metabolic alkalosis
C. Respiratory alkalosis
D. Metabolic acidosis

Correct answer: A

Rationale: The ABG values indicate respiratory acidosis. A pH below 7.40, a PaCO2 above 40 mm Hg, and a normal HCO3 level (24 mmol/L) suggest respiratory acidosis. In this case, the patient has an acidic pH (7.21) and an elevated PaCO2 (64 mm Hg), indicating inadequate ventilation. The normal HCO3 level suggests that compensation by the kidneys has not occurred, implying an acute event. Choices B, C, and D can be ruled out based on the given ABG values and the criteria for acid-base disorders.

4. A nurse in the medical-surgical unit is giving a patient with low blood pressure a hypertonic solution, which will increase the number of dissolved particles in his blood, creating pressure for fluids in the tissues to shift into the capillaries and increase the blood volume. Which of the following terms is associated with this process?

A. Hydrostatic pressure
B. Osmosis and osmolality
C. Diffusion
D. Active transport

Correct answer: B

Rationale: Osmosis is the movement of fluid from a region of low solute concentration to a region of high solute concentration across a semipermeable membrane. The number of dissolved particles contained in a unit of fluid determines the osmolality of a solution, which influences the movement of fluid between the fluid compartments. Giving a patient who has low blood pressure a hypertonic solution will increase the number of dissolved particles in the blood, creating pressure for fluids in the tissues to shift into the capillaries and increase the blood volume. Option A is incorrect; hydrostatic pressure refers to changes in water or volume related to water pressure. Option C is incorrect; diffusion is the movement of solutes from an area of greater concentration to lesser concentration. The solutes in an intact vascular system are unable to move, so diffusion should not normally take place. Option D is incorrect; active transport is the movement of molecules against the concentration gradient and requires ATP as an energy source. This process typically takes place at the cellular level and is not involved in vascular volume changes.