Digoxin
Key Points
- Digoxin is a cardiac glycoside that can improve contractility and help control rate/rhythm in selected pediatric cardiac conditions.
- Therapeutic benefit in congenital-HF pathways includes improved forward flow and reduced pulmonary/systemic congestion burden.
- Pediatric digoxin has a narrow safety margin; small dosing errors can cause severe dysrhythmia and death.
- In infants, hold parameters commonly include apical heart rate under 100 bpm before dosing unless provider order states otherwise.
- Hypokalemia and hypomagnesemia increase digoxin-toxicity risk, especially when combined with diuretic therapy.
Mechanism of Action
Digoxin has a positive inotropic effect by increasing myocardial contractile force and a negative chronotropic/conduction effect by slowing atrioventricular node conduction. This combination can improve cardiac output while reducing excessive ventricular response in selected rhythm contexts.
In pediatric heart-failure pathways, improved contractility and longer ventricular filling time can reduce blood backup in the lungs, improve systemic perfusion, and support renal perfusion.
Indications
- Symptom management in selected pediatric heart-failure pathways.
- Rate/rhythm support in provider-selected pediatric arrhythmia contexts.
- Adjunct in congenital-heart-disease care plans when hemodynamic goals include improved perfusion and reduced congestion burden.
Pediatric Dosing Context
Safety Focus
Use institution-specific pediatric protocols and exact provider orders; weight-based double-checks are mandatory before administration.
- Loading phase (digitalization) may be ordered to rapidly reach therapeutic effect (for example total loading dose over about 24 hours in divided dosing).
- Maintenance dosing is weight-based and often split into two daily doses.
- Pediatric reference example used in congenital-HF pathways: loading about
20-40 mcg/kgover 24 hours, then maintenance about8-10 mcg/kg/dayin two divided doses (always follow current provider order/protocol). - Renal impairment requires dose reduction because clearance is decreased.
- Serum digoxin levels are interpreted with timing context; levels are commonly drawn after adequate post-dose distribution interval.
Nursing Assessment
- Auscultate apical pulse for a full 60 seconds before each dose.
- Hold dose and notify provider for infant apical heart rate under 100 bpm unless alternative ordered threshold exists.
- Follow ordered age-specific heart-rate hold parameters for older children.
- Monitor ECG/rhythm trends for bradycardia, conduction delay, or new dysrhythmias.
- Assess for toxicity cues: nausea, vomiting, poor feeding, bradycardia, rhythm instability, and perfusion decline.
- Monitor potassium and magnesium trends closely; depletion lowers toxicity threshold.
- Reconcile concurrent medications, especially diuretics and other rate/rhythm agents.
Nursing Interventions
- Perform independent dose verification with weight-based calculation before administration.
- Administer digoxin separately (not mixed with formula or breast milk) to avoid incomplete dosing.
- Coordinate serum-level timing and electrolyte monitoring per pediatric protocol.
- Escalate suspected toxicity immediately and prepare for urgent rhythm/perfusion support.
- Reinforce caregiver teaching on schedule consistency and missed-dose handling; if a child vomits after a dose, do not redose and give the next scheduled dose unless provider gives different instructions.
- Reinforce immediate reporting of poor feeding, repeated vomiting, lethargy, bradycardia, or breathing changes.
- Document pre-dose apical heart rate, administered/held decision, and clinical response after dosing.
Narrow Therapeutic Index
Digoxin toxicity can progress quickly in infants and children; early signs must be treated as high-acuity findings.
Related Concepts
- heart-failure - Digoxin may support selected pediatric low-output states.
- congenital-heart-defects-acyanotic-and-cyanotic-patterns - Structural lesions often frame why digoxin is included in symptom-management plans.
- diuretics - Combined use increases need for potassium/magnesium surveillance.
- potassium-balance-disorders - Electrolyte abnormalities increase digoxin toxicity risk.
- cardiopulmonary-medication-classes-and-nursing-implications - Cross-class monitoring strategy for multi-drug cardiopulmonary regimens.