Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Systematic Review and Meta-Analysis Neonatology 2011;100:1–8 DOI: 10.1159/000322001 In Search of the Optimal Oxygen Saturation for Extremely Low Birth Weight Infants: A Systematic Review and Meta-Analysis Ola Didrik Saugstad   a Dagfinn Aune   b a  Department of Pediatric Research, Rikshospitalet, Oslo University Hospital, University of Oslo, Oslo, Norway; b  Department of Epidemiology and Public Health, Imperial College, London, UK 0.68), for bronchopulmonary dyslasia/lung problems it was 0.79 (0.64–0.97), and for mortality it was 1.27(1.01–1.60). Con- clusions: A low oxygen saturation approach reduces severe retinopathy of prematurity by 50%, i.e. from 20.9 to 9.5%, and bronchopulmonary dysplasia/lung problems by 25%, i.e. from 40.8 to 29.7%. Further randomized trials are needed to provide definite conclusions and to assess whether reduc- ing oxygen saturation has an impact on mortality among very and extremely low birth weight infants. Copyright © 2010 S. Karger AG, Basel Introduction The optimal oxygen saturation in the first postnatal weeks for very low and extremely low birth weight infants has not yet been defined. This is in spite of the fact that hyperoxia has been postulated for several decades to be an important pathogenetic factor both for retinopathy of prematurity (ROP) and bronchopulmonary dysplasia (BPD) or chronic lung disease. When the association be- tween high oxygen supplementation and retrolental fi- broplasia (later called ROP) was detected in the 1950s, it was thought that this condition was understood and could be prevented [1]. However, in the 1970s and 1980s it was clear that ROP has not been eradicated; by contrast, Key Words Arterial oxygen saturation  Bronchopulmonary dysplasia  Mortality  Pulse oximetry  Retinopathy of prematurity Abstract Background: The optimal arterial oxygen saturation in the first weeks of life is unknown for immature newborn infants. Objectives: To determine the effect of targeting high versus low oxygen saturation in the first weeks of life on the out- come of very low and extremely low birth weight infants. Methods: Randomized and observational studies were sought that compared the outcomes in babies with high or low oxygen saturation targeting assessed by pulse oximetry. Results: Ten studies were identified, of which 8 had severe retinopathy of prematurity (n = 3,811) and 8 had bronchopul- monary dysplasia/lung problems (n = 4,612) as outcomes. Two studies also provided survival data. The relative risk (RR) in favor of low SpO 2 was 0.42 (95% CI 0.34–0.51) for severe retinopathy of prematurity, 0.73 (95% CI 0.63–0.86) for bron- chopulmonary dysplasia/lung problems, and 1.12 (95% CI 0.86–1.45) for mortality. There was 1 randomized trial with retinopathy of prematurity, 3 with bronchopulmonary dys- plasia/lung problems, and 1 with mortality as the outcome. When analyzing the randomized trial separately, the RR (95% CI) for severe retinopathy of prematurity was 0.48 (0.34– Received: July 20, 2010 Accepted after revision: October 4, 2010 Published online: December 9, 2010 Prof. Ola Didrik Saugstad Pediatrisk Forskningsinstitutt Oslo Universitets Sykehus, Rikshospitalet, PB 4950 Nydalen NO–0424 Oslo (Norway) Tel. +47 2307 2790, Fax +47 2307 2780, E-Mail odsaugstad  @  rr-research.no © 2010 S. Karger AG, Basel 1661–7800/11/1001–0001$38.00/0 Accessible online at: www.karger.com/neo