A nurse is caring for a client who has a prescription for penicillin
V. Which of the following adverse effects is the priority for the nurse to monitor after the administration of the medication?

Choice A rationale: The respiratory rate is elevated from 22/min to 34/min, indicating worsening respiratory distress and increased work of breathing. Normal adult respiratory rates range from 12 to 20 breaths per minute. Tachypnea can signify hypoxia, infection progression, or impending respiratory failure, requiring immediate clinical reassessment and possible intervention to maintain adequate oxygenation and ventilation.

Choice B rationale: The blood pressure has dropped from 116/78 mm Hg to 98/62 mm Hg, indicating hypotension. Normal adult BP is around 120/80 mm Hg. This decrease suggests possible sepsis or shock, decreasing organ perfusion. Hypotension combined with other signs of systemic infection warrants urgent evaluation and treatment to prevent multi-organ dysfunction.

Choice C rationale: No incontinence is reported, so this finding is not clinically significant in this scenario. Incontinence can indicate neurological compromise or severe systemic illness but is absent here, making it a non-urgent parameter for follow-up in this context.

Choice D rationale: The client’s temperature remains elevated above normal (39.3°C to 39.4°C). Normal body temperature ranges from 36.5°C to 37.5°C. Persistent fever indicates ongoing infection but is less immediately life-threatening than respiratory or hemodynamic instability, thus not requiring immediate intervention compared to other parameters.

Choice E rationale: The heart rate has increased from 90 to 100 bpm, which is within mild tachycardia range but still within compensatory limits for fever and infection. Normal resting heart rate ranges from 60 to 100 bpm. Though elevated, it is less urgent than hypoxia or hypotension but requires monitoring.

Choice F rationale: The productive cough indicates pulmonary infection but is expected in pneumonia and not an immediate sign of deterioration needing urgent follow-up. The presence of cough aids diagnosis but does not directly indicate acute decompensation.

Choice G rationale: Oxygen saturation decreased from 94% to 86%, which is critically low (normal ≥ 95%). Hypoxemia suggests severe impairment in gas exchange and respiratory failure risk. Immediate oxygen supplementation and further respiratory support are required to prevent tissue hypoxia and organ damage.

Choice H rationale: Restlessness indicates hypoxia or anxiety but is a subjective symptom. While it signals distress, it is less precise than objective measures such as respiratory rate or oxygen saturation for urgent intervention.

Choice I rationale: Diminished lung sounds with crackles reflect pulmonary infection and consolidation but are physical examination findings not requiring immediate change in management compared to vital sign abnormalities indicating acute deterioration.

Choice J rationale: Large erythematous blotches suggest a possible allergic reaction to antibiotic therapy, posing a risk for anaphylaxis. This dermatologic change requires immediate assessment to prevent airway compromise or systemic hypersensitivity reactions, warranting urgent follow-up.

Choice A rationale

Magnesium levels within the normal range of 1.3 to 2.1 mEq/L do not directly indicate a therapeutic response to sodium polystyrene sulfonate. This medication is primarily used to exchange potassium ions for sodium ions in the gastrointestinal tract, thus lowering serum potassium. Magnesium homeostasis is regulated independently, often by renal excretion and dietary intake, and is not a direct target of this drug.

Choice B rationale

Calcium levels within the normal range of 9 to 10.5 mg/dL do not indicate a therapeutic response to sodium polystyrene sulfonate. This medication does not significantly impact calcium metabolism. Calcium regulation involves parathyroid hormone and vitamin D, and is separate from the ion-exchange mechanism of sodium polystyrene sulfonate.

Choice C rationale

Sodium levels within the normal range of 136 to 145 mEq/L, while desirable, do not directly indicate a therapeutic response to sodium polystyrene sulfonate. Although the medication exchanges potassium for sodium, leading to a potential increase in serum sodium, the primary therapeutic goal is potassium reduction, and a normal sodium level alone does not confirm this.

Choice D rationale

A potassium level of 4.8 mEq/L, which falls within the normal range of 3.5 to 5 mEq/L, indicates a therapeutic response to sodium polystyrene sulfonate. This medication functions as a cation-exchange resin, binding to potassium ions in the intestine and facilitating their excretion, thereby lowering elevated serum potassium levels to a safe range.