The nucleated red blood cell count at birth, the volume of red cell transfusions received, and the risk of developing retinopathy of prematurity.

BACKGROUND

Previous studies described an association between the NRBC count at birth and risk of developing retinopathy of prematurity (ROP). Other studies correlated red blood cell (RBC) transfusions with ROP. We are aware of no studies that examined both NRBC count and RBC transfusions, in the same cohort, on ROP risk.

STUDY

DESIGN

We retrospectively analyzed all infants in the Intermountain Health NICUs during the past four years who were born <32 weeks had a NRBC count at birth and had ROP examinations.

RESULTS

Records of 386 infants demonstrated that both factors are associated with ROP. For every 1000/µL increase in NRBC, severe (grade ≥3) ROP increased by 6.8% (95% CI, 3.0-10.0%). RBC transfusions were associated with ROP incidence and severity (p = 0.001). However, neither factor alone was either necessary or sufficient for ROP.

CONCLUSION

The NRBC count at birth and the volume of RBC transfusions both influence ROP severity.