A 6-month-old infant with a ventricular shunt presents with irritability, vomiting, and a bulging fontanel.
The nurse suspects:

Choice A rationale

Administering half the dose is inappropriate and lacks a scientific basis unless ordered by the provider, as it would likely be sub-therapeutic and fail to achieve the desired effect of improving myocardial contractility and reducing heart rate. Digoxin administration should be all or none based on parameters.

Choice B rationale

The acceptable apical pulse rate for administering digoxin to an infant is typically above 90-110 beats per minute (bpm). An apical pulse of 88 bpm falls below this generally accepted cutoff, indicating potential drug toxicity or the therapeutic effect lowering the rate too much, necessitating withholding the dose.

Choice C rationale

Administering double the dose is a dangerous, unscientific action that would significantly increase the risk of digoxin toxicity, which can cause severe cardiac arrhythmias, gastrointestinal symptoms, and potential cardiac arrest, particularly in infants who are highly susceptible to small dose changes.

Choice D rationale

The normal heart rate for an infant is significantly higher than 88 bpm. Holding the dose and notifying the provider is the required action. Bradycardia in an infant receiving digoxin is the cardinal sign of potential toxicity or an excessively deep therapeutic effect, and the provider must assess the situation before further dosing.

Choice A rationale

Cyanosis, a bluish discoloration of the skin and mucous membranes, indicates significant hypoxemia (low oxygen saturation) and is a sign of severe, life-threatening asthma exacerbation, not a mild to moderate presentation. In mild to moderate asthma, the body can usually compensate to maintain adequate tissue oxygenation despite airway constriction and inflammation.

Choice B rationale

Chest tightness is a subjective but common symptom in asthma, resulting from the bronchoconstriction and smooth muscle spasm that narrow the airways. The sensation is often described as a band around the chest, reflecting the increased work of breathing and the mechanical effort required to move air through the restricted bronchial passages.

Choice C rationale

An asthma cough is typically non-productive (dry) or, if secretions are present, it is often a mucoid, tenacious sputum. A consistently productive cough suggests other underlying conditions, such as infection (e.g., pneumonia) or bronchiectasis, rather than being the hallmark of a primary, mild-to-moderate asthma flare.

Choice D rationale

Wheezing, a high-pitched whistling sound, is the classic objective sign of asthma, caused by the vibration of air attempting to move rapidly through the severely narrowed, obstructed small airways (bronchioles) during respiration. It is often most prominent on expiration but can be present on inspiration during a significant episode.

Choice E rationale

Prolonged expiration occurs because the narrowed, inflamed airways obstruct the outflow of air, leading to air trapping and a higher residual volume. The patient must forcefully and slowly push air out against the resistance, making the expiratory phase last significantly longer than the inspiratory phase, a key sign of obstructive lung disease.