Liu X, et al. - In this study, plasma levels of human neutrophil peptides (HNPs) 1–3 were tested as predictors of impaired lung function post-cardiac surgery necessitating cardiopulmonary bypass (CPB) in infants and young children. In this population, correlation of elevated HNPs 1–3 levels immediately after CPB with impaired lung function was reported and HNPs 1–3 could serve as a quantifiable early alarmin biomarker for the onset of lung injury.

Methods

• This study included prospectively enrolled consecutive children younger than 3 years old who underwent cardiac surgery.
• Researchers measured plasma concentrations of HNPs 1–3 and inflammatory cytokines before, and immediately after CPB, as well as at 1 h, 12 h, and 24 h after CPB.

Results

• Out of a total of 30 patients enrolled in this study, 18 (60%) were infants.
• An immediate significant increase in plasma levels of HNPs 1–3 and the pro-inflammatory cytokine interleukin-6 (IL-6) was noted after CPB (P < 0.001), while IL-8 increased 1 h after the CPB operation (P=0.002).
• Furthermore, significantly elevated anti-inflammatory cytokine IL-10 levels were detected after CPB compared with the baseline (P < 0.001).
• Researchers found that the stepwise multiple linear regression analysis revealed an independent correlation between plasma HNPs 1–3 levels immediately after CPB and the declined lung function, as reflected by the PaO₂/FiO₂ ratio on the first 2 days after operation (for the first day: OR, -1.067, 95% CI, -0.548 to -1.574; P < 0.001; for the second day: OR, -0.667, 95% CI, -0.183 to -1.148; P=0.009) and prolonged mechanical ventilation time (OR, 0.039, 95% CI, 0.005 to 0.056; P=0.011).
• In addition, they noted that plasma levels of HNPs 1–3 and IL-10 returned to the baseline values, while IL-6 and IL-8 levels remained significantly higher than baseline 24 h after CPB (P ≤ 0.01).