ATI RN
Fluid and Electrolytes ATI
1. The nurse is assessing the patient for the presence of a Chvostek's sign. What electrolyte imbalance does a positive Chvostek's sign indicate?
- A. Hypermagnesemia
- B. Hypomagnesemia
- C. Hypocalcemia
- D. Hyperkalemia
Correct answer: C
Rationale: Chvostek's sign is characterized by a brief contraction of the upper lip, nose, or side of the face and is indicative of hypocalcemia, making choice C the correct answer. Hypomagnesemia (choice B) is associated with Trousseau's sign, not Chvostek's sign. Hypermagnesemia (choice A) is not related to Chvostek's sign. Hyperkalemia (choice D) is not typically associated with Chvostek's sign; instead, it may present with muscle weakness and cardiac arrhythmias.
2. 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.
3. The healthcare provider is evaluating a patient's laboratory results. Based on the laboratory findings, what results will cause the release of an antidiuretic hormone (ADH)?
- A. Increased serum sodium
- B. Decreased serum sodium
- C. Decrease in serum osmolality
- D. Decrease in thirst
Correct answer: A
Rationale: The correct answer is A: Increased serum sodium. When serum sodium levels increase, it triggers the release of ADH by the posterior pituitary gland. ADH helps in retaining water, reducing urine output, and maintaining fluid balance. Choices B, C, and D are incorrect because decreased serum sodium, decrease in serum osmolality, and decrease in thirst do not stimulate the release of ADH.
4. A nurse admitting a patient with a history of emphysema reviews her past lab reports and notes that the patient's PaCO2 has been 56 to 64 mmHg. The nurse will be cautious administering oxygen because:
- A. The patient's calcium will rise dramatically due to pituitary stimulation.
- B. The oxygen will increase the patient's intracranial pressure and create confusion.
- C. The oxygen may cause the patient to hyperventilate and become acidotic.
- D. Using oxygen may result in the patient developing carbon dioxide narcosis and hypoxemia.
Correct answer: D
Rationale: When PaCO2 chronically exceeds 50 mm Hg, it creates insensitivity to CO2 in the respiratory medulla, and the use of oxygen may result in the patient developing carbon dioxide narcosis and hypoxemia. Choice A is incorrect because administering oxygen does not lead to a dramatic rise in calcium due to pituitary stimulation. Choice B is incorrect because administering oxygen does not directly increase intracranial pressure or create confusion. Choice C is incorrect because administering oxygen to a patient with emphysema and high PaCO2 levels is more likely to cause respiratory depression than hyperventilation and acidosis.
5. 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.
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