83 - Changes in cerebral oxygenation during feeding of preterm newborns

The developing brain is extremely sensitive to hypoxemia and hyperoxemia, affecting long-term morbidity. Non-
invasive regional cerebral oxygenation (rScO₂ ) can be useful to assess the impact of clinical practices on rScO₂ .
Sola et al (2003) reported changes in rScO₂  during tube placement and feeding in 23 preterm newborns (PtNB).
Technology and availability of neonatal sensors to measure rScO₂  has significantly improved. We recently published
high variability in the values of rScO₂  during major and minor procedures in the NICU.

Objective:

To describe changes in rScO₂  values during feeding by nasogastric tube in PtNB in the NICU

Design/Methods:

Descriptive study in PtNB from 25 to 36 weeks. Cerebral oximetry was monitored using O3® Regional oximetry
(Masimo, Irvine, CA) with ROOT with neonatal sensors placed on the left forehead of the PtNB. rScO₂ values were
recorded: a) 5 minutes before the start of tube feeding (PRE), b) during feeding (INTRA) and c) 5 minutes after
completion (POST). Measurements at each stage are summarized by descriptive statistics. PRE/INTRA and POST
values were compared using ANOVA test for paired data, using STATA 12.0.

Results:

We evaluated 81 PtNB: 31 ± 3 weeks, weight 1400 ± 600 gr, 66% male, 35% in ventilatory assistance. All PtNB had
a gastric tube in place for hours or days before starting the study. Before feeding (PRE) rScO₂  values were 71.6 ±
5.6% (60% to 88%). During gavage milk administration (INTRA) rScO₂  did not vary significantly (± 2%) in 35
newborns (43%); in 32 (39.5%) rScO₂ decreased between -3 to -14% and in the rest (13.5%) it increased between
+3 to +11%. After 5 minutes of completing the feeding (POST), 20/32 PtNB (62%) continued registering lower rScO₂
values than PRE. The differences were statistically significant (p = 0.02) and alert about the variability in cerebral
oxygenation with routine tube feeding. We could not associate the decrease in rScO₂  ( >2%) with sex, weight, GA,
nor requirement for ventilatory assistance. However, the effect of the type of milk, temperature and speed of infusion
remain to be explored, to be able to evaluate if there are practices during feeding that cause fewer variations and
perhaps can be safer in PtNB.

Conclusion(s):

Routine gastric tube feeding causes changes in cerebral oxygenation in PtNB. The implications and ways to prevent
them require to deepen these studies, taking into account relevant information provided by the feasibility of modern
non-invasive rScO₂ monitoring of the neonatal brain.
Acknowledgement: Research grant from SIBEN