The nurse is caring for a client with severe diarrhea. The nurse monitors the client closely, understanding that this client is at risk for developing which acid-base disorder?

Choice A: Elderly patients are at a higher risk for dehydration due to physiological changes that come with aging, such as decreased kidney function and physical changes to the body's water balance systems. Additionally, fever increases metabolic rate and fluid loss, and nausea and vomiting prevent adequate fluid intake, further increasing the risk of dehydration.

Choice B: While intentionally limiting fluid intake can lead to dehydration, the body's thirst mechanism in a healthy teenager is typically strong enough to prevent severe dehydration.

Choice C: Diarrhea can certainly lead to dehydration, but a young, otherwise healthy patient typically has a stronger ability to recover from fluid loss than an elderly patient.

Choice D: Infants are at a higher risk for dehydration than older children and adults due to their smaller body weight and higher turnover of water and electrolytes, but in this case, the elderly patient's multiple risk factors put them at a higher risk overall.

Choice A reason: This is correct because respiratory acidosis is a condition where the blood pH is lower than the normal range of 7.35 to 7.45, due to impaired gas exchange or hypoventilation, which causes carbon dioxide to accumulate in the blood. COPD is a chronic lung disease that obstructs the airways and reduces the oxygen intake and carbon dioxide output. This leads to respiratory acidosis in the patient.

Choice B reason: This is incorrect because respiratory alkalosis is a condition where the blood pH is higher than the normal range of 7.35 to 7.45, due to hyperventilation, which lowers the carbon dioxide in the blood. COPD does not cause hyperventilation, but rather hypoventilation.

Choice C reason: This is incorrect because metabolic alkalosis is a condition where the blood pH is higher than the normal range of 7.35 to 7.45, due to a loss of acids or an excess of bases in the body. COPD does not affect the metabolic system directly, but rather the respiratory system.

Choice D reason: This is incorrect because metabolic acidosis is a condition where the blood pH is lower than the normal range of 7.35 to 7.45, due to an excess of acids or a loss of bases in the body. COPD does not affect the metabolic system directly, but rather the respiratory system.