Article

Impact of chorioamnionitis on exhaled nitric oxide and endotracheal aspirate levels of nitrites–nitrates and interleukin‐8 in mechanically ventilated preterm neonates

Pediatric Pulmonology (Impact Factor: 2.38). 05/2011; 46(6):595 - 603. DOI: 10.1002/ppul.21410

ABSTRACT Objectives
To assess the influence of maternal chorioamnionitis on early exhaled nitric oxide (NO) and levels of nitrites–nitrates and interleukin (IL)-8 in endotracheal aspirate fluid in mechanically ventilated preterm neonates.Study DesignCross-sectional study.Patient–Subject SelectionBetween September 2007 and August 2009, 54 mechanically ventilated preterm neonates were included. Patients were divided into two groups according to the presence or absence of maternal chorioamnionitis, and those without chorioamnionitis (controls) were further stratified into two subgroups by birth weight < or ≥2,000 g.MethodologyThe ventilator used was a Babylog 8000. The NO level assessed was the plateau value given by the software of the Sievers NOA apparatus. Collection of endotracheal aspirate fluid samples was performed coinciding with routine aspirations and using the dry technique.ResultsThe two groups of control neonates showed statistically significant differences in exhaled NO expressed as nl/min and normalized exhaled NO expressed as either nl/min or nl/min/kg, so they are not homogeneous and cannot be used in clinical practice. Serum C-reactive protein and endotracheal aspirate levels of nitrites–nitrates were significantly higher in the chorioamnionitis group than in controls (3.6 vs. 1.07 µmol/L; P = 0.035). Nitrites–nitrates levels were positively correlated with exhaled NO in ppb (ρ = 0.367; P = 0.006). Minute exhaled endogenous NO was significantly higher in the chorioamnionitis group (0.48 vs. 0.27 nl/min/kg; P = 0.021).Conclusions
In mechanically ventilated preterm infants weighing <2,000 g, maternal chorioamnionitis was associated with an increase of early exhaled NO (nl/min/kg) and serum levels of C-reactive protein and levels of nitrites–nitrates in endotracheal aspirate fluid. Pediatr. Pulmonol. 2011; 46:595–603. © 2011 Wiley-Liss, Inc.

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