Pausing TPN to Decrease Abnormal Newborn Screens: A NICU Quality Initiative

Purpose/Objectives: Detection of metabolic and genetic disorders via the newborn screen (NBS) remains a great diagnostic achievement in medicine. For preterm infants, and other sick neonatal patients, screening is challenging, with many false positives, leading to the need for repeat testing, which has significant cost to the hospital. The rate of abnormal NBS in very low birth weight neonates (VLBW, <1500g) at the University of Virginia was 72% overall, with 23% of these abnormalities being due to the effect of total parenteral nutrition (TPN) on the amino acid profile. If the NBS is obtained when the neonate is not receiving TPN, the rate of abnormal amino acid profiles decreases significantly. This reduces the number of repeat screens that need to be sent, therefore, potentially reducing the number of blood draws for the patient. Our goal was to decrease the number of abnormal NBS due to TPN in our Neonatal Intensive Care Unit (NICU) to minimize unnecessary blood draws and metabolic workups.

Design/Methods: This was a quality improvement (QI) project done in the NICU at a tertiary care center. Our intervention required TPN to be paused, while a dextrose containing fluid was run (to maintain euglycemia), 4 hours prior to collecting the NBS. During PDSA cycle 1, TPN was paused at 1400 and the NBS was collected at our standard line change time at 1800. This did not decrease the number of blood draws per patient because our neonates were not typically having labs drawn at 6pm. During PDSA cycle 2, we aimed to decrease the number of blood draws per neonate and thus paused the TPN at 0000 to enable NBS collection at 0400 with routine morning lab work (Figure 1).

Results: Our Intervention allowed us to decrease the rate of abnormal screens from 72% to 37%, p <0.0001, 95% CI 0.18 to 0.47 (Figure 2), and decrease hospital costs. In 2018-2019 for 85 patients, the hospital spent $21,114 to perform the NBS in our VLBW population. In 2020-2021 for 84 patients, it has only cost $14,352. This is a cost savings of $6,762 in our VLBW population alone. Although we did see a slight increase in the percent of screens drawn >48 hours, from 3% in the baseline data to 7% after the intervention, this increase was not statistically significant (p= 0.3, 95% CI -0.1 to 0.03).

Conclusion/Discussion: So, as you can see, by pausing TPN for 4 hours prior to drawing the NBS, we were able to decrease the number of abnormal NBS in one of our more vulnerable populations without impacting nursing workflow. This saves neonates unnecessary metabolic workups and blood draws and additionally saves the hospital money by decreasing the number of NBS cards used.