Correlations of Umbilical Venous Erythropoietin and Nucleated Erythrocytes with Blood Gases

Chun, Sun Hee

Abstract

OBJECTIVE
To assess the correlation of erythropoietin(EPO) levels and number of nucleated erythrocytes(NRBC) with measurements of blood gases and to investigate the obstetrical factors influencing the levels of EPO and number of NRBC in umbilical venous blood of non asphyxiated neonates.
METHODS
Measurements of EPO levels by RIA, number of NRBC per 100 white blood cells(WBC) by blood smear and measurement blood gases were performed at delivery in umbilical venous blood from 117 cases of neonates with gestational age ranged from 29 to 42 weeks, including 77 cases of non-asphyxia and 40 cases of asphyxia. Statistcial analysis included Student's t test, linear regression and linear correlation using SPSS 7.0 version statistical package.
RESULTS
The umbilical venous EPO level is correlated significantly with the number of NRBC (r2 =0.204, p<0.05). The level of EPO as well as the number of NRBC showed inverse correlation with umbilical venous pH(r=-0.223, P<0.05 ; r=-0.896, p<0.05). Number of NRBC showed correlation with pCO2 (r=0.700, P<0.01) and base deficit (r=0.316, p<0.01). The mean level of EPO in non-asphyxiated neonates was 26.2 +/-16.1 mIU/mL showing correlation with gestational age and birth weight and higher level in neonates delivered vaginally than those delivered by elective cesarean section (27.1+/-17.0 vs 18.8+/-6.7 mIU/mL, p=0.012). The mean number of NRBC in non-asphyxiated neonates was 2.5+/-2.1/100 wbc showing no difference according to mode of delivery, gestational age and birth weight.
CONCLUSION
Number of NRBC not only correlated with cord gas parameters more strongly but also was less influenced by the obstetrical factors than EPO level.