A nurse on a mother-baby unit is caring for a 2-day-old baby boy. The patient was seen by a urologist at 0000 and was diagnosed with hypospadias, Which order by the pediatrician is contraindicated?

Digoxin is a medication commonly used to treat heart failure and certain heart rhythm disorders. However, it has a narrow therapeutic window, and digoxin toxicity can occur if the drug accumulates in the body to excessive levels. One of the hallmark signs of digoxin toxicity is severe bradycardia, which means an abnormally slow heart rate. Bradycardia can result from the effects of digoxin on the electrical conduction system of the heart, leading to an irregular or slowed heartbeat.

While other symptoms can occur in digoxin toxicity, such as gastrointestinal symptoms (like nausea and vomiting), neurological symptoms (like confusion and visual disturbances), and even respiratory distress in severe cases, extreme bradycardia is a key and often life-threatening sign that requires immediate medical attention.

Constipation (A) and headache (C) can also occur as side effects of digoxin but are less specific to digoxin toxicity and may not be considered cardinal manifestations.

Respiratory distress (B) may occur if the bradycardia leads to inadequate cardiac output, causing pulmonary congestion, but it is not a primary or cardinal symptom of digoxin toxicity. Extreme bradycardia is typically the more immediate and prominent concern.

Obstructive congenital heart defects involve the presence of narrowing or constriction in various parts of the heart or major blood vessels. In the case of coarctation of the aorta, there is a narrowing or constriction in the aorta, which can obstruct blood flow. Aortic stenosis involves the narrowing of the aortic valve, and pulmonic stenosis involves the narrowing of the pulmonary valve. These defects create obstacles to the normal flow of blood out of the heart, leading to increased pressure within the heart and affecting blood circulation.

The other categories mentioned are:

B. Mixing defects: These defects involve abnormal mixing of oxygenated and deoxygenated blood within the heart, typically due to septal defects like atrial septal defect (ASD) or ventricular septal defect (VSD).

C. Decreased pulmonary blood flow: These defects are characterized by reduced blood flow to the lungs, such as in the tetralogy of Fallot.

D. Increased pulmonary blood flow: These defects involve increased blood flow to the lungs, often due to shunting of blood from the left side of the heart to the right side, as seen in atrial septal defects or ventricular septal defects.