Cerebral, renal and mesenteric regional oxygen saturation of term infants during transition.

OBJECTIVE

To measure cerebral regional oxygen saturation (CrSO2), renal regional oxygenation saturation (RrSO2) and mesenteric tissue regional oxygen saturation (MrSO2) during immediate transition and continuously for the first 9 hours of age. Fractional tissue oxygen extraction of the brain (CtFOE), kidneys (RtFOE), splanchnic tissue (MtFOE) were also assessed.

STUDY DESIGN

Prospective, observational study of 61 term infants, delivered by elective caesarean section. Using near-infrared spectroscopy, changes in CrSO2, RrSO2, MrSO2 and changes in CtFOE, RtFOE and MtFOE were measured all through the first 9 hours of life. All the episodes of feeding during this period were recorded.

RESULTS

Mean CrSO2 increased quickly to 7 minutes, with no further changes. On the other hand, mean RrSO2 and mean MrSO2 increased for 10 minutes and thereafter they remained on their newly reached level. RrSO2 and MrSO2 were significantly lower at 3-4-5-6-7 minutes of life compared to the CrSO2 (p<0.05). RtFOE and MtFOE were significantly higher at 3-4-5-6-7 minutes of life compared to the CtFOE (p<0.05). During feeding, CrSO2, RrSO2 and MrSO2 did not significantly change.

CONCLUSIONS

During early adaptive period, oxygen delivery is preserved to 'vital' organs, like brain, at the expense of kidneys and splanchnic tissue. Term infants can provide for the increasing metabolic activity of the intestinal tract during feeding periods without compromising oxygenation.