A nurse is caring for a client who has hypomagnesemia due to chronic alcohol use disorder. Which of the following actions should the nurse take?

Choice A reason:

pH 7.50, PaCO2 40 mm Hg, HCO3- 30 mEq/L. This choice is correct because it shows a high pH, a normal PaCO2, and a high HCO3-, which are consistent with metabolic alkalosis. Metabolic alkalosis occurs when there is a loss of acid or a gain of base in the body fluids, such as from prolonged nasogastric suctioning. The kidneys try to compensate by excreting more bicarbonate, but this process is slow and incomplete.

Choice B reason:

pH 7.35, PaCO2 35 mm Hg, HCO3- 24 mEq/L. This choice is incorrect because it shows normal values for pH, PaCO2, and HCO3-, which indicate no acid-base imbalance. A client with metabolic alkalosis would have an elevated pH and bicarbonate level.

Choice C reason:

pH 7.25, PaCO2 50 mm Hg, HCO3- 26 mEq/L. This choice is incorrect because it shows a low pH, a high PaCO2, and a normal HCO3-, which are consistent with respiratory acidosis. Respiratory acidosis occurs when there is impaired gas exchange or hypoventilation, leading to an accumulation of carbon dioxide in the blood. The kidneys try to compensate by retaining more bicarbonate, but this process is slow and incomplete.

Choice D reason:

pH 7.30, PaCO2 30 mm Hg, HCO3- 18 mEq/L. This choice is incorrect because it shows a low pH, a low PaCO2, and a low HCO3-, which are consistent with metabolic acidosis. Metabolic acidosis occurs when there is a gain of acid or a loss of base in the body fluids, such as from diabetic ketoacidosis or diarrhea. The lungs try to compensate by increasing the rate and depth of breathing to expel more carbon dioxide, but this process is fast and limited.

Choice A reason:

Decreased urine specific gravity indicates improvement in hydration status. Urine specific gravity is a measure of the concentration of solutes in the urine. It reflects the ability of the kidney to concentrate or dilute urine. A high urine specific gravity (>1.030) indicates concentrated urine, which can be caused by dehydration, reduced renal blood flow, or increased fluid loss. A low urine specific gravity (<1.010) indicates diluted urine, which can be caused by overhydration, diuretic use, or impaired renal function. A normal urine specific gravity ranges from 1.010 to 1.030.

Choice B reason:

Increased hematocrit level indicates worsening of dehydration. Hematocrit is the percentage of red blood cells in the total blood volume. It is affected by the plasma volume and the number of red blood cells. A high hematocrit (>47% for males and >42% for females) indicates hemoconcentration, which can be caused by dehydration, polycythemia, or hypoxia. A low hematocrit (<37% for males and <32% for females) indicates hemodilution, which can be caused by overhydration, anemia, or hemorrhage. A normal hematocrit ranges from 37% to 47% for males and 32% to 42% for females.

Choice C reason:

Decreased skin turgor indicates persistent dehydration. Skin turgor is the elasticity of the skin that reflects its hydration status. It is assessed by pinching a fold of skin on the chest, abdomen, or forearm and releasing it. Normally, the skin should return to its original position in less than 3 seconds. If the skin remains elevated or takes longer to return, it indicates poor skin turgor, which can be caused by dehydration, aging, or edema.

Choice D reason:

Increased serum osmolarity indicates worsening of dehydration. Serum osmolarity is a measure of the concentration of solutes in the blood plasma. It reflects the balance between water and electrolytes in the body fluids. A high serum osmolarity (>300 mOsm/kg) indicates hyperosmolarity, which can be caused by dehydration, hypernatremia, hyperglycemia, or mannitol infusion. A low serum osmolarity (<280 mOsm/kg) indicates hypoosmolarity, which can be caused by overhydration, hyponatremia, syndrome of inappropriate antidiuretic hormone secretion (SIADH), or diuretic use. A normal serum osmolarity ranges from 280 to 300 mOsm/kg.