A patient has a hemoglobin of 7.1 g/dL. The nurse understands that anemia is likely to result in which of the following?

Choice A reason: Sodium 125 mEq/L (normal 135-145 mEq/L) indicates hyponatremia, likely from excessive sweating during running, causing water retention or sodium loss. Low sodium disrupts cellular osmosis, leading to cerebral edema, explaining lethargy and pallor. This critical imbalance affects nerve conduction and muscle function, requiring urgent correction to prevent seizures or coma.

Choice B reason: Potassium 4.2 mEq/L (normal 3.5-5.0 mEq/L) is within normal range. Potassium regulates muscle and nerve function, including cardiac rhythm. Normal levels do not explain lethargy or pallor, as they ensure proper membrane potential and muscle contraction. In this scenario, potassium is not a concern compared to severe hyponatremia affecting neurological status.

Choice C reason: Calcium 4.8 mg/dL (normal 8.5-10.2 mg/dL) indicates hypocalcemia, which can cause muscle cramps or tetany. However, lethargy and pallor are more directly linked to hyponatremia’s neurological effects. Calcium affects muscle contraction and nerve signaling, but its impact is less acute than sodium’s role in osmotic balance and cerebral function here.

Choice D reason: Magnesium 2.0 mEq/L (normal 1.7-2.2 mEq/L) is normal. Magnesium supports muscle and nerve function, including ATP production. Normal levels do not contribute to lethargy or pallor, which are more likely due to sodium imbalance affecting brain hydration. Magnesium is not a priority concern in this acute presentation.

Choice A reason: Administering eye drops to the lower conjunctival sac ensures optimal drug absorption and minimizes corneal irritation. The conjunctival sac, a mucous membrane, allows medication to spread across the eye surface, treating conjunctivitis by targeting bacterial or inflammatory processes. This method avoids systemic absorption via the nasolacrimal duct, enhancing local efficacy and safety.

Choice B reason: Dropping medication onto the cornea risks irritation or injury, as the cornea is a sensitive, avascular tissue responsible for light refraction. Conjunctivitis treatment requires medication to contact the conjunctiva, not the cornea directly. This method could cause discomfort and reduce drug efficacy, as it does not target the inflamed conjunctival tissue.

Choice C reason: The sclera by the outer canthus is not ideal for eye drop administration. The sclera, a tough connective tissue, has poor drug absorption compared to the conjunctival sac. Drops placed here may run off, reducing contact with the inflamed conjunctiva in conjunctivitis, leading to ineffective treatment and potential waste of medication.

Choice D reason: The sclera by the inner canthus is near the nasolacrimal duct, increasing the risk of systemic drug absorption rather than local treatment of conjunctivitis. Drops should target the lower conjunctival sac to ensure contact with the inflamed tissue, maximizing therapeutic effect while minimizing systemic side effects like tachycardia from certain medications.