Which laboratory results should the nurse closely monitor in a client who has end-stage renal disease (ESRD)?

Choice A reason: This is the correct answer because serum potassium, calcium, and phosphorus are laboratory results that should be closely monitored in a client who has end-stage renal disease (ESRD). ESRD is a chronic condition that causes irreversible loss of kidney function and accumulation of waste products and fluids in the body. Potassium is an electrolyte that regulates nerve and muscle function and cardiac rhythm. ESRD can cause hyperkalemia (high potassium levels) due to reduced excretion by the kidneys. Hyperkalemia can cause cardiac arrhythmias, muscle weakness, or paralysis. Calcium and phosphorus are minerals that maintain bone health and acid-base balance. ESRD can cause hypocalcemia (low calcium levels) due to impaired vitamin D metabolism and hyperphosphatemia (high phosphorus levels) due to reduced excretion by the kidneys. Hypocalcemia can cause muscle cramps, tetany, or seizures. Hyperphosphatemia can cause soft tissue calcification, bone pain, or fractures.

Choice B reason: Erythrocytes, hemoglobin, and hematocrit are laboratory results that are not as critical as serum potassium, calcium, and phosphorus in a client who has end-stage renal disease (ESRD). Erythrocytes are red blood cells that carry oxygen from the lungs to the tissues. Hemoglobin is a protein in erythrocytes that binds oxygen. Hematocrit is the percentage of blood volume that is occupied by erythrocytes. ESRD can cause anemia (low erythrocyte, hemoglobin, and hematocrit levels) due to reduced production of erythropoietin, a hormone that stimulates erythrocyte formation, by the kidneys. Anemia can cause fatigue, pallor, or shortness of breath.

Choice C reason: Leukocytes, neutrophils, and thyroxine are laboratory results that are not as relevant as serum potassium, calcium, and phosphorus in a client who has end-stage renal disease (ESRD). Leukocytes are white blood cells that fight infection and inflammation. Neutrophils are a type of leukocyte that respond to bacterial infection. Thyroxine is a hormone that regulates metabolism and growth. ESRD can cause leukopenia (low leukocyte levels) and neutropenia (low neutrophil levels) due to impaired immune function and increased susceptibility to infection. ESRD can also cause hypothyroidism (low thyroxine levels) due to reduced clearance of thyroid hormones by the kidneys. Hypothyroidism can cause weight gain, cold intolerance, or depression.

Choice D reason: Blood pressure, heart rate, and temperature are not laboratory results, but vital signs that should be monitored in a client who has end-stage renal disease (ESRD). Blood pressure is the force of blood against the walls of the arteries. Heart rate is the number of times the heart beats per minute. Temperature is the measure of body heat. ESRD can cause hypertension (high blood pressure) due to fluid overload and activation of the renin-angiotensin-aldosterone system, a hormonal pathway that regulates blood pressure and fluid balance. Hypertension can cause headache, chest pain, or stroke. ESRD can also cause tachycardia (high heart rate) due to anemia, fluid overload, or electrolyte imbalance. Tachycardia can cause palpitations, dizziness, or heart failure. ESRD can also cause fever (high temperature) due to infection or inflammation. Fever can cause chills, sweating, or delirium.

Choice A reason: Administering a half dose now is not a safe instruction for the nurse to provide, as this can result in overdosing or underdosing the infant, depending on how much of the medicine was absorbed or expelled. This is a contraindicated choice.

Choice B reason: Giving another dose is not a prudent instruction for the nurse to provide, as this can cause digoxin toxicity, which can be life-threatening for the infant. This is another contraindicated choice.

Choice C reason: Mixing the next dose with food is not a relevant instruction for the nurse to provide, as this does not address the current situation and can affect the absorption and effectiveness of digoxin. This is a distractor choice.

Choice D reason: Withholding this dose is a sensible instruction for the nurse to provide, as this can prevent adverse effects and allow the infant's serum digoxin level to be checked before giving another dose. Therefore, this is the correct choice.