PE22.3 | Cardiac Failure — Summary & Reflection

KEY TAKEAWAYS

Cardiac failure in children is a clinical syndrome of inadequate cardiac output relative to metabolic demands, manifesting with age-specific features: neonates — tachypnoea, poor perfusion, hepatomegaly; infants — feeding difficulty, diaphoresis, failure to thrive, hepatomegaly (Ross Grade III/IV); older children — exercise intolerance, orthopnoea, peripheral oedema. The most common aetiology in infants is left-to-right shunting from large VSD or PDA (onset at 6–8 weeks as PVR falls). Pathogenesis involves compensatory neurohormonal activation (RAAS, sympathetic) that causes long-term maladaptive remodelling. Investigation: CXR (cardiothoracic ratio >0.55 = cardiomegaly; plethora), ECG (arrhythmia identification), echocardiography (structural diagnosis and EF). Management: acute — IV furosemide 1–2 mg/kg/dose, inotropes (dobutamine/milrinone); chronic — furosemide, digoxin (digitalising dose 25–40 mcg/kg in neonates/infants/children, divided ½→¼→¼, maintenance ¼ of TDD bd), ACE inhibitors (captopril 0.1–0.5 mg/kg/dose). Digoxin toxicity presents as bradycardia, AV block, and vomiting — hypokalaemia from furosemide is the most common precipitant.

REFLECT

Consider the infant in the opening scenario again. Two weeks of sweating during feeds, falling asleep mid-bottle, barely gaining weight — these are the symptoms a parent reports because they notice their child is 'struggling.' But without a framework linking 'struggling to feed' to 'cardiac failure from a large VSD', this information is invisible. Reflect on what 'failure to thrive' and 'diaphoresis during feeds' mean to you now versus before this module. How would you explain to the parents what is happening and why their baby needs medication and likely surgery? What aspect of the digoxin dosing calculation felt most difficult — and what would help you commit the scheme to memory before your paediatric posting?