Current practice of pulse oxygen saturation targets and limits in neonatal intensive care units in Australia and New Zealand

Lower pulse oxygen saturation (SpO2) targets have been advocated for preterm infants over the last decade and have been associated with less morbidity (1–3). However, most data are based on observational studies. Only one randomized-controlled trial compared two SpO2 target regimens, 91–94% versus 95–98%, in preterm infants born <30 weeks gestational age once they had reached a corrected age of 32 weeks gestational age. This trial showed a significant increase in bronchopulmonary dysplasia and home oxygen therapy in the high-saturation study arm but no difference in mortality or retinopathy of prematurity (4). Further controlled studies were lacking until recently. In 2010, the SUPPORT trial revealed a moderate, though, significant increase in mortality in extremely low gestational age infants when nursed in SpO2 targets of 85–89% versus 91– 95% (5). Subsequently, the BOOST-II trials in the UK, Australia and New Zealand with a similar study design closed enrolment prematurely following a preliminary meta-analysis of their and the SUPPORT trial’s mortality data (6). A pooled analysis confirmed better survival in the higher SpO2 target group. Long-term outcome data are not available yet. We surveyed current practice of SpO2 targets and limits in neonatal intensive care units (NICU) in Australia and New Zealand 5 months after publication of the preliminary SUPPORT ⁄ BOOST-II meta-analysis. An email survey was sent to all 26 tertiary NICUs in Australia and New Zealand in September 2011. A reminder email was sent 3 weeks after the first email to those who had not replied to the survey. The survey included the following items: • Did your NICU participate in the BOOST-II trial? • Please specify your unit’s SpO2 targets ⁄ limits according to gestational age before publication of the SUPPORT trial. • Did your unit change your SpO2 targets ⁄ limits after publication of the SUPPORT trial in May 2010? • Did your unit change your SpO2 targets ⁄ limits after closure of BOOST-II recruitment and communication of its preliminary results in April 2011? • If your unit changed SpO2 targets ⁄ limits, please specify your new SpO2 targets ⁄ limits. • If your unit has not changed the SpO2 targets ⁄ limits, are you considering a change, or will you keep your current SpO2 targets ⁄ limits? All survey participants consented their survey data to be used for publication. As the survey did not include any patient data, ethics committee approval was not sought. Twenty (76.9%) completed surveys returned after the reminder email. Of those, 18 NICUs participated in the BOOST-II trial. None of the units changed their SpO2 targets ⁄ limits after publication of the SUPPORT trial; however, eleven NICUs changed them following the communication of the preliminary mortality analysis of the pooled SUPPORT ⁄ BOOST-II data. Table 1 shows those NICUs that have made changes to their SpO2 targets ⁄ limits; Table 2 shows those that have not made any changes. Our survey, conducted 5 months after publication of the preliminary meta-analysis, shows a rather scattered picture how tertiary neonatal units in Australia and New Zealand managed SpO2 targets prior to the preliminary meta-analysis, and how they responded to its results. Half of the NICUs used SpO2 targets of 88–92% prior to SUPPORT ⁄ BOOST-II, a range exactly in the middle of the two trialled SpO2 ranges in SUPPORT ⁄ BOOST-II. However, some units used this target for all infants whereas others use higher targets for infants above 31–32 weeks gestation, or for term infants. Five NICUs do not have defined SpO2 targets, and Acta Pædiatrica ISSN 0803–5253