[Prognostic utility of inflammatory indexes in critically ill newborns]

Critically ill newborns (NB) are susceptible to serious complications due to their immature immune system.

To know the prognostic utility of inflammatory indexes in critically ill NBs.

Observational, analytical, longitudinal, prospective study. We included NBs hospitalized, critically ill and non-critically ill, who had a complete blood count at 12 hours of life (initial) and within 24 hours prior to discharge due to improvement or death (final). Systemic immune-inflammatory Index (SII), Neutrophil/Lymphocyte Ratio (NLR) and Platelets/Lymphocyte Ratio (PLR) were analyzed. There was follow-up from birth to discharge.

211 patients of 33 (32-34) weeks of gestation, weight 1.569 (1.480-1.720) kg. 106 critical NB and 105 non-critical NB, with 50 deaths in the former group, were analyzed. The final NLR ≥ 1.38 (sensitivity [S] 58%, specificity [Sp] 58%, AUC 0.60 [p 0.006]) identified critically ill NBs compared to non-critical ill NBs; final NLR ≥ 1.84 (S 71%, Sp 71%, AUC 0.79 [p < 0.0001]) identified critically ill NBs who died compared to all those who survived; final SII ≥ 255.411 x 103 (S 55%, Sp 56%, AUC 0.60 [p 0.047]) and final NLR ≥ 1.75 (S 76%, Sp 76%, AUC 0.84 [p < 0.0001]) identified critical NBs who died from those who survived.

The final NLR predicts which NBs may perish with respect to all who survive. The final NLR and SII predict among critically ill NBs who may die.