Earlier Apgar score increase in severely depressed term infants cared for in Swedish level III units with 40% oxygen versus 100% oxygen resuscitation strategies: a population-based register study.
OBJECTIVE
The aim of this study was to evaluate whether a resuscitation strategy based on administration of 40% oxygen influences mortality rates and rates of improvement in 5-minute Apgar scores, compared with a strategy based on 100% oxygen administration.


METHODS
A population-based study evaluated data from 4 Swedish perinatal level III centers during the period of 1998 to 2003. During this period, the centers used either of 2 resuscitation strategies (initial oxygen administration of 40% or 100%). Live-born, singleton, term infants with 1-minute Apgar scores of <4, with a birth weight appropriate for gestational age, and without major malformations were included in the study (n = 1223).


RESULTS
Infants born in hospitals using a 40% oxygen strategy had a more rapid Apgar score increase than did infants born in hospitals using a 100% oxygen strategy; however, no difference remained at 10 minutes. The mean Apgar score increased from 2.01 at 1 minute to 6.74 at 5 minutes in the 2 hospitals initiating resuscitation with 40% oxygen, compared with 2.01 to 6.38 in the 2 hospitals using 100% oxygen, with a mean difference in Apgar score increases of 0.36. At 5 minutes, 44.3% of infants born in the hospitals using 100% oxygen had an Apgar score of <7, compared with 34.0% of infants at the hospitals using 40% oxygen. At 10 minutes, the mean Apgar scores were 8.16 at the hospitals using 40% oxygen and 8.07 at the hospitals using 100% oxygen. There were no significant differences in rates of neonatal death, hypoxic ischemic encephalopathy, or seizures in relation to the 2 oxygen strategies.


CONCLUSIONS
Severely depressed term infants born in hospitals initiating resuscitation with 40% oxygen had earlier Apgar score recovery than did infants born in hospitals using a 100% oxygen strategy.
Hellström-Westas
Lena
L
Department of Pediatrics, University Hospital, SE-221 85 Lund, Sweden. lena.hellstrom-westas@med.lu.se
Forsblad
Kristina
K
Sjörs
Gunnar
G
Saugstad
Ola Didrik
OD
Björklund
Lars J
LJ
Marsál
Karel
K
Källén
Karin
K
D001034:Apgar Score; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000628:therapy; D010100:Oxygen / Q000008:administration & dosage*; D012042:Registries; D012151:Resuscitation / Q000379:methods*; D012720:Severity of Illness Index; D013548:Sweden; D013997:Time Factors
D010100:Oxygen