A nurse is caring for a child who is postoperative following surgical correction of tetralogy of Fallot. Which of the following findings should the nurse identify as an indication of heart failure?

Postoperative management of Tetralogy of Fallot requires monitoring for cardiac dysfunction during the recovery phase. The nurse must distinguish between expected postoperative recovery and clinical signs of heart failure, which reflect the heart's inability to meet the body's metabolic demands. Choice A rationale Heart failure results in reduced cardiac output, leading to systemic fatigue and an inability to tolerate physical activity. In children, this manifests as exercise intolerance or exhaustion during feeding, indicating that the heart cannot sustain necessary metabolic workloads. Choice B rationale Tachycardia, rather than bradycardia, is a primary compensatory mechanism in heart failure. The sympathetic nervous system increases the heart rate to maintain cardiac output when stroke volume is compromised. Normal pediatric heart rates vary significantly by age. Choice C rationale Heart failure typically causes tachypnea and increased respiratory effort due to pulmonary congestion or compensatory mechanisms for low oxygen delivery. Decreased respirations are more indicative of respiratory failure or sedative effects rather than active congestive heart failure. Choice D rationale Rapid weight gain, not weight loss, is a classic sign of heart failure due to fluid retention and systemic edema. Weight loss is more commonly associated with chronic malnutrition or high metabolic demands in untreated congenital heart defects.