Elevation of brain natriuretic peptide levels in children with septic shock.

OBJECTIVES: 1) To compare brain natriuretic peptide levels in pediatric patients with septic shock with both children admitted to the pediatric intensive care unit without infection and with healthy subjects; and 2) to evaluate the correlation between brain natriuretic peptide with severity of illness and with myocardial dysfunction in children with septic shock.

DESIGN: : Prospective, observational study.

SETTING: Children's Hospital pediatric intensive care unit.

PATIENTS: Children from age 2 wks to 18 yrs. Thirteen children with septic shock requiring inotropic support, 12 healthy controls, and five critically ill patients without infection or heart disease were evaluated.

INTERVENTIONS: For patients with septic shock, brain natriuretic peptide was measured within 6 hrs of admission and throughout the pediatric intensive care unit course. Echocardiograms were performed within 12 hrs of admission and then repeated if the patient continued to require inotropic support. For controls, one measurement was performed.

MEASUREMENTS AND MAIN RESULTS: Children with septic shock had an elevated (p < 0.0001) brain natriuretic peptide on admission (median 115 pg/mL [range 26-2960]) when compared with healthy (9 pg/mL [5-30]) and pediatric intensive care unit controls (10 pg/mL [5-30]). In patients with septic shock, brain natriuretic peptide at 12 hrs correlated directly with Pediatric Risk of Mortality III score (rs = .80, p = 0.002) and inversely with fractional shortening (rs = -.66, p = 0.014). In children with cold shock, brain natriuretic peptide at 12 hrs (718 pg/mL) [63-1530] was higher (p = 0.007) than in those with warm shock (208 pg/mL [20-366]). There was no pattern (p > 0.05) observed for brain natriuretic peptide over time.

CONCLUSIONS: Brain natriuretic peptide measured early after admission is increased in children with septic shock, especially in those with cold shock. In addition, the level at 12 hrs correlates with both severity of illness and myocardial dysfunction. Brain natriuretic peptide may be useful in assessing myocardial dysfunction from septic shock, particularly in identifying children with cold shock. Further studies are warranted to determine whether this measurement will be helpful in guiding therapy in pediatric septic shock.