If an infant on digoxin has a heart rate of 88 bpm, what should be suspected?

In infants receiving digoxin, a heart rate of 88 beats per minute is particularly noteworthy, as digoxin is a medication that decreases heart rate through its action on the heart’s conduction system. In the pediatric population, bradycardia, or a heart rate below the normal resting range, can indicate digoxin toxicity, especially in younger children whose normal heart rates are generally higher.

Digoxin toxicity can manifest in various ways, one of which is bradycardia, as the drug increases vagal tone and can disrupt normal electrical conduction in the heart. It's crucial to monitor heart rates closely in infants on digoxin, as they are more susceptible to the effects of the drug given their smaller body size and the high sensitivity of their cardiovascular system.

While bradycardia might have other explanations, such as normal responses based on the medication or other underlying conditions, the context that the infant is being treated with digoxin makes toxicity the most likely concern. Thus, a heart rate of 88 bpm should certainly raise suspicion for digoxin toxicity in this clinical scenario.