Cerebral oxygenation during umbilical arterial blood sampling in very low birth weight neonates.

OBJECTIVE: Umbilical arterial blood sampling (UABS) has been associated with cerebral oxygen saturation (CrSO2 ) decrements in very low birth weight (VLBW) neonates. We sought to determine patient- and UABS procedure-related factors contributing to this effect.

STUDY DESIGN: In this prospective cohort study, cerebral near-infrared spectroscopy was performed during UABS procedures in VLBW neonates. Analyses were conducted to determine subject- and procedure-related factors correlating with CrSO2 decrements.

RESULT: Thirty subjects (mean (±SD) 27 ± 2 week GA and 1058 ± 279 g BW) underwent 84 UABS procedures between 5 and 183 postnatal hours. Six (20%) experienced CrSO2 decrements, less than previously reported. Subjects with CrSO2 decrements had earlier GA and lower BW, though these were not statistically significant differences. CrSO2 decrements occurred with lower pre- and post-UABS pulse oximetry (p = 0.004; p < 0.001), lower arterial oxygen partial pressure (p < 0.001), lower baseline CrSO2 (p = 0.01), and faster "priming" blood reinfusion (p = 0.03) and saline flush (p = 0.02).

CONCLUSION: UABS procedures appear to be associated with CrSO2 decrements more commonly among VLBW neonates already experiencing disturbances in cerebral oxygen delivery-consumption balance. Shorter durations of UABS procedural components may contribute to CrSO2 decrements.