Blood gases and retinopathy of prematurity: the ELGAN Study.
OBJECTIVE
This study tested the hypothesis that preterm infants who had a blood gas derangement on at least 2 of the first 3 postnatal days are at increased risk for more severe retinopathy of prematurity (ROP).


METHODS
1,042 infants born before 28 weeks' gestational age (GA) were included. An infant was considered to be exposed if his/her blood gas measure was in the highest or lowest quartile for GA on at least 2 of the first 3 postnatal days.


RESULTS
Multivariable models adjusting for confounders indicate that exposure to a PCO(2) in the highest quartile predicts ROP (stage 3, 4 or 5: OR = 1.6, 95% CI = 1.1-2.3); zone 1: 2.0, 1.1-3.6; prethreshold/threshold: 1.9, 1.2-3.0; plus disease: 1.8, 1.1-2.9). Estimates are similar for a low pH for zone 1 (2.1, 1.2-3.8), prethreshold/threshold (1.8, 1.1-2.8), but did not quite achieve statistical significance for ROP stage 3, 4, or 5 (1.4, 0.9-2.0) and plus disease (1.5, 0.9-2.4). A PaO(2) in the highest quartile for GA on at least 2 of the first 3 postnatal days was associated with a doubling of the risk of ROP in zone 1 (2.5, 1.4-4.4) and of prethreshold/threshold disease (2.1, 1.4-3.3), a 70% risk increase for plus disease (1.7, 1.04-2.8), while a 40% risk increase for ROP stage 3 or higher did not achieve statistical significance (1.4, 0.96-2.0).


CONCLUSIONS
Infants exposed to high PCO(2), low pH and high PaO(2) appear to be at increased risk of more severe ROP.
Hauspurg
Alisse K
AK
Yale University School of Medicine, New Haven, Connecticut, USA.
Allred
Elizabeth N
EN
Vanderveen
Deborah K
DK
Chen
Minghua
M
Bednarek
Francis J
FJ
Cole
Cynthia
C
Ehrenkranz
Richard A
RA
Leviton
Alan
A
Dammann
Olaf
O
D002245:Carbon Dioxide / Q000097:blood*; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D010100:Oxygen / Q000097:blood*; D011247:Pregnancy; D012178:Retinopathy of Prematurity / Q000097:blood*
D002245:Carbon Dioxide; D010100:Oxygen