The Clinical Significance of Apgar Score and Umbilical Arterial Blood Gas Analysis on Preterm Infant Delivered Vaginally

Park, Ji Yong; Chung, Jin Hoon; Park, Kyo Hoon; Cho, Yong Kyoon; Choi, Hoon; Kim, Bok Rin; Lee, Hong Kyoon; Ko, Su Jin; Seo, Joung Sik; Yoo, Tae Hwan

Abstract

OBJECTIVE
The Apgar score has long been used to determining birth asphyxia and assessing early neonatal status and long-term outcome. Unfortunately, some components of this system depend upon subjective interpretation. Also, although, low Apgar score, Most of newborns are relatively healthy. The objective of our studt is attempt to assure the linical significance of Apgar score and umbilical cord blood gas analysis on assessing status of uncomplicated preterm infants delivered vaginally.
METHODS
The present study was performed in attempt to compare umbilical arterial blood gas values for uncomplicated preterm infants delivered vaginally with low 1 and 5 minutes Apgar score (<7) with those for term or preterm infant with normal 1 and 5 minutes score (>7), each other, The present study included 82 uncomplicated term infants delivered vaginally and 24 preterm infants. Inclusion criteria of our study is as follows: 1) Singleton neonate with vertex presentation, 2) No congenital malformation, 3) Infants whose mother had no obstetrical and medical complications, 4) Immediately after delivery, umbilical arterial blood was sampled, before first breathing of neonate, 5) Infants applied Apgar score at I minute and again 5 minutes after birth, and 6) Infants whose mothers gestational age was estimated by ultrasonography during first-trimester of pregnancy. The statistical analysis was performed by Mann-Whitney U test and Fishers exact test.
RESULTS
1) There was no significant difference in umbilical arterial blood gas values between uncomplicated preterm infants delivered vaginally with low 1 and 5 minutes Apgar score (<7) and term infants with normal score (>7). 2) There was no significant difference in umbilical arterial blood gas values between uncomplicated preterm infants delivered vaginally with low 1 and 5 minutes Apgar score (<7) and preterm infants with normal score (>7). 3) There was significant difference in frequency of lower Apgar score (<7) between term (2%[2/82]) and preterm infants (38%[9/24]), but not in frequency of acidemia (defined as less than pH 7.2) (28%[23/82] Vs 33%[8/24]).
CONCLUSION
The Apgar score is not a reliable indieator of well-being in preterm neonate. We recommend umbilical arterial blood sampling at delivery of preterm infant with low Apgar score, because umbilical cord blood gas indices on objective means of assessing birth status of the newbarn and more useful than Apgar score in ruling out birth asphyxia.