Organ dysfunction and mortality in preterm neonates with late-onset bloodstream infection

BackgroundOrgan dysfunction (ODF) in late-onset bloodstream infection (LBSI) is associated with increased risk of adverse outcomes. However, no established definition of ODF exists among preterm neonates. Our objective was to describe an outcome-based ODF definition for preterm infants, and assess factors associated with mortality.MethodsThis is a six-year retrospective study of neonates <35 weeks gestational age, >72 h of age, with non-CONS bacterial/fungal LBSI. Discriminatory ability of each parameter for mortality was evaluated: base deficit <=-8 mmol/L (BD8), renal dysfunction (urine output <1 cc/kg/h or creatinine >= 100 mu mol/L), hypoxic respiratory failure (HRF, ventilated, FiO(2) = 1.0), or vasopressor/inotrope use (V/I). Multivariable logistic regression analysis was performed to derive a mortality score.ResultsOne hundred and forty-eight infants had LBSI. BD8 had the highest individual predictive ability for mortality (AUROC = 0.78). The combination BD8 + HRF + V/I was used to define ODF (AUROC = 0.84). Fifty-seven (39%) infants developed ODF, among which 28 (49%) died. Mortality increased inversely relative to GA at LBSI-onset (aOR 0.81 [0.67, 0.98]) and directly relative to ODF occurrence (12.15 [4.48, 33.92]). Compared to no-ODF, ODF infants had lower GA and age at illness, and higher frequency of Gram-negative pathogen.ConclusionsAmong preterm neonates with LBSI, significant metabolic acidosis, HRF, and vasopressor/inotrope use may identify infants high risk for mortality. These criteria could help identify patients for future studies of adjunctive therapies.ImpactSepsis-related organ dysfunction is associated with increased risk of adverse outcomes.Among preterm neonates, significant metabolic acidosis, use of vasopressors/inotropes, and hypoxic respiratory failure may identify high-risk infants.This can be used to target research and quality improvement efforts toward the most vulnerable infants.

Automated summary

This study aimed to establish an outcome-based definition for organ dysfunction (ODF) in preterm infants and evaluate factors associated with mortality. Significant metabolic acidosis, use of vasopressors/inotropes, and hypoxic respiratory failure can identify high-risk infants.