What is the initial management for cardiogenic shock due to myocarditis in pediatrics?

Initial Management of Cardiogenic Shock Due to Myocarditis in Pediatrics

For pediatric patients with cardiogenic shock due to myocarditis, the initial management should include individualized titration of inotropic support with epinephrine, levosimendan, dopamine, or dobutamine, along with careful hemodynamic monitoring and consideration of mechanical circulatory support when pharmacological therapy is insufficient. 1

Initial Assessment and Stabilization

• Immediate evaluation with ECG and echocardiography is essential for diagnosis and to guide management in all pediatric patients with suspected cardiogenic shock due to myocarditis 2
• Continuous monitoring of ECG, arterial pressure, and tissue perfusion markers (mental status, extremity warmth, urine output, lactate levels) should be established 2
• Invasive arterial line placement is recommended for continuous blood pressure monitoring and frequent blood sampling 2
• Respiratory status must be carefully assessed, as respiratory failure is common in pediatric myocarditis with cardiogenic shock 3, 4

Pharmacological Management

• Inotropic support must be individually titrated as there is wide variability in clinical response to vasoactive drugs in pediatric cardiogenic shock 1
• It is reasonable to use any of the following inotropes for support in pediatric cardiogenic shock due to myocarditis:
  • Epinephrine 1
  • Dobutamine 1
  • Dopamine (caution with doses >7 mcg/kg/min as it may increase pulmonary vascular resistance) 1
  • Levosimendan (has shown improved ejection fraction and reduced duration of catecholamine infusions in small studies) 1
• Milrinone may be beneficial, particularly in cases with low cardiac output, though evidence is stronger for post-cardiac surgery cases than for myocarditis 1, 5
• Norepinephrine may be considered for maintaining mean arterial pressure >65 mmHg, though data specifically in pediatric cardiogenic shock are limited 1

Ventilation Strategy

• There is insufficient evidence to support or refute early intubation before the onset of respiratory failure in pediatric shock 1
• However, mechanical ventilation should be considered when there are signs of respiratory distress or failure, as respiratory compromise is common in pediatric myocarditis 3, 4
• If intubation is necessary, careful attention to hemodynamics during the procedure is essential as these patients are at high risk for cardiac arrest during intubation 1

Mechanical Circulatory Support

• Early consideration of extracorporeal membrane oxygenation (ECMO) is warranted in pediatric myocarditis with cardiogenic shock that is refractory to pharmacological therapy 1, 6
• Very low-quality evidence suggests that pre-cardiac arrest use of ECMO may be beneficial in children with acute fulminant myocarditis 1
• Factors associated with ECMO use in pediatric myocarditis include arrhythmias, low left ventricular ejection fraction, and high vasoactive-inotropic scores 7
• Survival rates with mechanical support in pediatric myocarditis can approach 70%, with many patients recovering normal cardiac function without requiring transplantation 6, 7

Monitoring and Ongoing Assessment

• Serial echocardiography to assess ventricular function and response to therapy 2
• Regular assessment of end-organ perfusion through clinical examination, urine output, and laboratory parameters (lactate, liver enzymes, renal function) 2, 3
• Continuous ECG monitoring for arrhythmias, which are common complications of myocarditis and may indicate need for escalation of support 7
• Left ventricular ejection fraction at 48 hours has been identified as a significant prognostic indicator in pediatric myocarditis 7

Common Pitfalls to Avoid

• Delaying echocardiographic evaluation, which is fundamental for diagnosis and management 2
• Relying solely on blood pressure for assessment without evaluating tissue perfusion markers 2
• Excessive fluid administration, which may worsen cardiac function in myocarditis 4
• Failing to consider mechanical circulatory support early when pharmacological therapy is insufficient 6, 7
• Overlooking arrhythmias, which are common in myocarditis and may require specific management 7