Packed red blood cells transfusion in neonates: effect on FiO2 and PaO2/SaO2 ratio, and implications for neonatal saturation targeting.

Nitzan, Itamar; Hammerman, Cathy; Mimouni, Francis B; Bin-Nun, Alona

OBJECTIVE To assess the effect of blood transfusions in neonates on partial pressure of oxygen in arterial blood (PaO2), arterial hemoglobin oxygen saturation (SaO2) and arterial hemoglobin oxygen saturation as measured by pulse oximetry (SpO2). STUDY DESIGN Retrospective study of neonates that received a first blood transfusion while having an indwelling arterial line. We compared PaO2, SaO2, SpO2, SaO2/PaO2 ratio and fraction of inspired oxygen (FiO2) 12 h before and after blood transfusion. RESULTS Post-transfusion neonates had higher PaO2 and SaO2, had lower SaO2/PaO2 ratio, and received higher FiO2 with no change in SpO2. CONCLUSIONS Post-transfusion, neonates had lower hemoglobin oxygen affinity. They received higher FiO2 and had higher PaO2 at the same SpO2. We speculate that FiO2 was increased in order to maintain SpO2. Larger prospective trials are needed to confirm our findings.