A patient has end-stage chronic obstructive pulmonary disease (COPD). Which acid-base imbalance would be predictable in a patient with COPD?

Choice A reason: This is incorrect because polyuria is a sign of hyponatremia, not hypernatremia. Polyuria is the excessive production of urine, which can cause fluid loss and sodium dilution.

Choice B reason: This is correct because dry mucous membranes are a sign of hypernatremia. Dry mucous membranes are caused by dehydration, which can occur in hypernatremia due to fluid shifting from the intracellular to the extracellular space.

Choice C reason: This is incorrect because diarrhea is a sign of hyponatremia, not hypernatremia. Diarrhea is the frequent and watery passage of stool, which can cause fluid and electrolyte loss.

Choice D reason: This is incorrect because intense thirst is a sign of both hyponatremia and hypernatremia. Intense thirst is a result of the body's attempt to restore fluid balance and osmolarity.

Choice E reason: This is incorrect because vomiting is a sign of both hyponatremia and hypernatremia. Vomiting is a reflex action that expels the contents of the stomach, which can cause fluid and electrolyte loss or imbalance.

Choice A reason: This is incorrect because 120 to 140 mEq/L is a low range for serum sodium, which indicates hyponatremia. Hyponatremia can cause confusion, lethargy, seizures, and coma.

Choice B reason: This is correct because 135 to 145 mEq/L is the normal range of serum sodium in adults. Sodium is essential for fluid balance, nerve transmission, and muscle contraction.

Choice C reason: This is incorrect because 150 to 160 mEq/L is a high range for serum sodium, which indicates hypernatremia. Hypernatremia can cause thirst, dry mouth, agitation, and convulsions.

Choice D reason: This is incorrect because 165 to 175 mEq/L is a very high range for serum sodium, which indicates severe hypernatremia. Severe hypernatremia can cause irreversible brain damage and death.