Which nursing diagnoses are appropriate for an infant with a large patent ductus arteriosus (PDA)?

Choice A rationale

A high-pitched cry in an infant can be indicative of increased intracranial pressure (ICP) due to stretching of the meninges or irritation of the central nervous system. However, it is a non-specific sign that may also relate to pain or general distress. Normal infant crying is variable, but this specific quality suggests a potentially serious neurological issue.

Choice B rationale

Poor feeding is a non-specific sign of general illness in an infant, reflecting overall malaise or potentially a depressed level of consciousness secondary to increased ICP. Reduced appetite or difficulty sucking/swallowing suggests decreased neurological function or systemic distress but is often less immediately concerning than vital sign changes.

Choice C rationale

Separated cranial sutures (diastasis) and a bulging fontanelle are classic, late-stage physical findings in infants with chronic or acutely escalating ICP. The unfused sutures provide a compensatory mechanism for the expanding volume, but once separated, it signifies a substantial, long-standing pressure increase.

Choice D rationale

Bradycardia (abnormally slow heart rate) is the most concerning part of the Cushing's Triad (hypertension, bradycardia, and irregular respirations), which is a late and critical physiological response to dangerously elevated ICP. The reduced heart rate is a reflex response mediated by the brainstem to maintain cerebral perfusion pressure (CPP).

Choice A rationale

Decreased urine output (oliguria, typically <1 mL/kg/hour in a child) is a sign of poor renal perfusion due to reduced cardiac output and is characteristic of later, decompensated shock. In early, compensated septic shock, systemic vascular resistance (SVR) is often reduced (warm shock), and the compensatory mechanisms may still maintain adequate renal blood flow and normal urine output.

Choice B rationale

Cool extremities result from intense peripheral vasoconstriction as a compensatory mechanism to shunt blood to vital organs. This is characteristic of hypovolemic or cold septic shock (high SVR). However, in the more common early warm septic shock in children, peripheral vasodilation (low SVR) leads to flushed, warm extremities, not cool ones.

Choice C rationale

Normal blood pressure (BP) (systolic BP within the normal range, which varies by age, e.g., >90 mmHg in a school-aged child) is the hallmark of compensated shock. Compensatory mechanisms, primarily tachycardia and mild vasoconstriction, are successfully maintaining cardiac output and thus adequate mean arterial pressure, despite underlying circulatory dysfunction.

Choice D rationale

Tachycardia (elevated heart rate, normal range varies by age, e.g., >130 bpm in a toddler) is one of the earliest and most reliable signs of all forms of shock in children. It represents a critical cardiovascular compensatory mechanism to increase cardiac output (Cardiac Output = Stroke Volume×Heart Rate) in response to systemic vasodilation and early hypovolemia characteristic of sepsis.