ATI Fluid and Electrolytes

Correct Answer: B

Rationale: The symptoms described, including tingling in the lips and fingers, intermittent spasms, and increased muscle tone, are indicative of tetany, which is a common manifestation of hypocalcemia. Hypocalcemia can lead to neuromuscular irritability, causing symptoms such as paresthesias and muscle spasms. Hypophosphatemia primarily affects the central nervous system, resulting in seizures and coma. Hypermagnesemia typically presents with hypoactive reflexes and somnolence. Hyperkalemia can cause paresthesias and anxiety, but in this case, the patient's symptoms are more suggestive of hypocalcemia.

Correct Answer: A

Rationale: The correct statement is that people with less body fat have more body water. This is because fat tissue contains less water compared to lean tissue, so individuals with less body fat generally have a higher percentage of body water. Choice B is incorrect as infants actually have more water per pound than adults due to their higher body water content. Choice C is incorrect as males typically have more body water per pound than females. Choice D is incorrect as infants have a higher water content per pound compared to adults.

Correct Answer: C

Rationale: The correct answer is C: increased aldosterone secretion. Aldosterone, a hormone produced by the adrenal glands, increases sodium reabsorption in the kidneys, leading to retention of sodium and water in the interstitial fluid. Increased aldosterone secretion enhances the reabsorption of sodium, thereby increasing its retention. Choice A is incorrect because decreased aldosterone secretion would lead to less sodium reabsorption and increased excretion. Choice B is incorrect because increased ADH secretion primarily affects water reabsorption rather than sodium. Choice D is incorrect because decreased ADH secretion would lead to increased water excretion but not necessarily affect sodium retention.

Correct Answer: D

Rationale: The correct answer is D, ADH and aldosterone. Both antidiuretic hormone (ADH) and aldosterone increase water retention by the kidneys, thereby increasing blood volume. ADH acts on the kidneys to increase water reabsorption, while aldosterone acts on the kidneys to promote sodium reabsorption, leading to water retention. Choice A, ADH, is partially correct as it alone increases water retention. Choice B, aldosterone, is also partially correct as it alone increases water retention. Choice C, ANH (atrial natriuretic hormone), actually decreases water retention by promoting sodium excretion and inhibiting aldosterone release.

Correct Answer: D

Rationale: When a patient exhibits signs and symptoms of third-spacing, where fluid moves out of the intravascular space but not into the intracellular space, hypovolemia is expected. This leads to a decreased circulating blood volume. Increased calcium and magnesium levels are not typically associated with third-spacing fluid shift. Burns usually result in acidosis rather than alkalosis, making metabolic alkalosis an incorrect choice. Therefore, hypovolemia is the correct answer in this scenario.