Repeated measurements are not better than initial measurement of Score for Neonatal Acute Physiology-II for prediction of in-hospital mortality in severely septic preterm neonates

Abstract

The ability of serial versus single time application of ‘Score for Neonatal Acute Physiology, version II’ (SNAP-II) to predict mortality at day 14 in preterm neonates < 34 weeks with severe sepsis was studied prospectively over 1-year in a tertiary care neonatal unit. SNAP-II scores were recorded at the onset of severe sepsis (T0) and serially at 24 (T1), 48 (T2) and 72 (T3) hours later. Delta scores (Δ SNAP-II) were derived from the difference between any two SNAP-II scores. Seventy-one preterm neonates were enrolled. Baseline characteristics were similar in survivors (n = 53) and non-survivors (n = 18). Median SNAP-II scores at all the four time points were significantly higher in non-survivors (p < 0.001). The Δ SNAP-II (T0 – T2) score was significantly different between non-survivors and survivors (mean difference: -14.7; 95% CI: -29, -0.9; p = 0.02), while the difference was not significant between T0 – T1 and T0 – T3. Initial SNAP-II score had a significantly better discriminating ability for day 14 mortality (AUC (95% C.I): 0.83 (0.70–0.93)) than Δ SNAP-II scores at various time points (AUC (95% C.I): 0.59 (0.41–0.75) for T0 – T1, 0.70 (0.50–0.87) for T0 – T2 and 0.64 (0.38–0.89) for T0 – T3). Conclusion: Initial SNAP-II is better than Δ SNAP-II scores in predicting 14-day mortality in severely septic preterm neonates. Non-survivors had a significantly higher serial SNAP-II scores compared to survivors. Serial SNAP-II score do not have additional value in predicting mortality of preterm neonates with severe sepsis.