Background: The influence of severity of anemia and cardiac output (CO) on cerebral oxygenation (CrSO2) and on the change in CrSO2 following packed red blood cell (PRBC) transfusion in preterm infants has not been evaluated. The objectives of the current study were to evaluate the effect of pre-transfusion hemoglobin (Hb) and CO-weighted oxygen delivery index (ODI) on CrSO2 and on the post-transfusion CrSO2 change.
Methods: Preterm infants of <32 weeks gestational age (GA) receiving PRBC transfusion were enrolled. Infants received 15 ml/kg PRBC over 3 h. CrSO2 by near-infrared spectroscopy and CO by electrical velocimetry were recorded for 1 h pre-ransfusion and post transfusion. ODI was defined as pre-transfusion Hb × CO.
Results: Thirty infants of 26.6 ± 2.0 weeks GA were studied at 19 ± 12 days. Pre-transfusion Hb was 9.8 ± 0.6 g/dl. Pre-transfusion CrSO2 correlated with pre-transfusion ODI (R2 = 0.1528, p = .044) but not with Hb level. The pre-transfusion to post-transfusion CrSO2 change correlated with pre-transfusion ODI (R2 = 0.1764, p = .029) but not with Hb level. CrSO2 increased from 66 ± 6% to 72 ± 7% post transfusion (p < .001), while arterial oxygen saturation, heart rate, and CO did not change.
Conclusion: In these infants, the pre-transfusion ODI was a better indicator of brain oxygenation and its improvement post transfusion than Hb alone. The role of CO and tissue oxygenation monitoring in assessing the need for transfusion should be evaluated.