Sepsis in Children

Background

• Sepsis is defined as a documented or suspected infection plus a cluster of symptoms known as systemic inflammatory response syndrome (SIRS).
  • SIRS in pediatrics is classified as ≥ 2 of following (1 must be abnormal temperature or leukocyte count)
    • Core temperature > 38.5 degrees C (101.3 degrees F) or < 36 degrees C (96.8 degrees F)
    • Leukocyte count depressed or elevated for age in absence of chemotherapy-induced leukopenia or > 10% immature neutrophils
    • Abnormal heart rate
      • Heart rate > 2 standard deviations above normal for age in the absence of external stimulus, drugs, or painful stimuli or otherwise unexplained persistent depression in mean heart rate over 0.5 hours
      • Heart rate mean < 10th percentile for age in absence of external vagal stimulus, beta blocker drugs, or congenital heart disease, or otherwise unexplained persistent depression in mean heart rate over 0.5 hours (in infants < 12 months old)
    • Mean respiratory rate > 2 standard deviations above normal for age or mechanical ventilation for acute process unrelated to general anesthesia or underlying neuromuscular disease
  • Severe sepsis is defined as sepsis with end organ dysfunction.
  • Septic shock indicates sepsis with cardiovascular dysfunction (hypotension as defined by age group, vasopressor requirement, or other markers of end organ hypoperfusion).
• Causes of sepsis vary with immunization status, antibiotic use, geographic region, and emerging organisms.
• Prevalent etiologic agents vary by age group
  • Infants < 2 months old at risk of sepsis due to group B Streptococcus, Escherichia coli, Listeria monocytogenes, herpes simplex virus.
  • Children > 1-2 months at risk of sepsis from community acquired organisms such as Streptococcus pneumonia or Neisseria meningitides.
  • Most common causes of bacteremia in children < 18 years old in a developed setting were S. pneumoniae, Staphylococcus aureus, and E. coli.
• Primary bacteremia is more common in infants while almost half of older children have primary respiratory tract infections.
• Complications of sepsis can impact any organ system and pediatric sepsis carries an estimated hospital mortality of 2%-10%, with a higher mortality in those with severe sepsis and septic shock (14%-25%).

Evaluation

• Early identification and treatment of pediatric sepsis is critical as early reversal of septic shock is associated with improved survival.
  • Perform bedside assessment to identify signs and symptoms of SIRS.
  • Obtain blood tests, including (but not limited to) complete blood count with differential, complete metabolic panel, liver function tests, amylase and lipase, coagulation studies, lactate, ScvO₂ (if available), arterial blood gas.
  • Perform microbiologic testing to assess for source including but not limited to blood cultures, urinalysis and urine cultures, sputum culture, cerebrospinal fluid culture and Gram stain as need based patient's history and exam.
• Blood cultures should be obtained before administration of antibiotics when possible but should not delay administration of antibiotics (Strong recommendation).

Management

• Respiratory support
  • Respiratory distress and hypoxia should be managed with oxygen administered by face mask, high-flow nasal cannula, nasopharyngeal continuous positive airway pressure, or mechanical ventilation (Strong recommendation).
• Hemodynamic support
  • Begin with fluid resuscitation of isotonic crystalloid (or albumin) up to 20 mL/kg over 5-10 minutes, which may need to be repeated.
  • Begin maintenance isotonic 10% dextrose solution and, if necessary, fluid resuscitation and inotrope infusion until a central line is available (Weak recommendation).
  • For fluid refractory shock, begin vasopressors or inotropes based on whether cold shock or warm shock is present.
  • Titrate resuscitation to establish the following therapeutic end points (Weak recommendation):
    • normal mental status
    • capillary refill ≤ 2 seconds
    • warm extremities
    • normal pulses
    • urine output > 1 mL/kg/hour
    • normal blood pressure
    • central venous oxygen saturation ScvO₂ saturations ≥ 70%
    • cardiac index between 3.3 and 6 L/minute/m²
• Other support
  • Administer empiric antibiotics within 1 hour of identification of severe sepsis and pursue early and aggressive source control (Strong recommendation).
  • Use hydrocortisone infusion (stress dose steroids) in children with fluid refractory, catecholamine-resistant shock, and suspected or proven absolute adrenal insufficiency (Strong recommendation).
  • Control hyperglycemia with insulin therapy to keep blood sugar < 180 mg/dL (Strong recommendation).
  • Administer sedation for critically ill mechanically ventilated patients (Strong recommendation).
  • Maintain hemoglobin level at or above 10 g/dL post resuscitation.
  • Consider Extracorporeal membrane oxygenation (ECMO) for refractory pediatric septic shock and respiratory failure (Weak recommendation).