SHORT COMMUNICATION

Current practice of pulse oxygen saturation targets and limits in neonatalintensive care units in Australia and New ZealandKai König (kaikonig@gmail.com), James R HolbertonDepartment of Paediatrics, Mercy Hospital for Women, Melbourne, Vic., Australia

CorrespondenceKai Konig, Mercy Hospital for Women, Departmentof Paediatrics, 163 Studley Road, Melbourne 3084,Vic., Australia.Tel: 0061-3-84584444 |Fax: 0061-3-94595389 |Email kaikonig@gmail.com

Received23 January 2012; accepted 31 January 2012.

DOI:10.1111/j.1651-2227.2012.02628.x

Lower pulse oxygen saturation (SpO2) targets have beenadvocated for preterm infants over the last decade and havebeen associated with less morbidity (1–3). However, mostdata are based on observational studies. Only one random-ized-controlled trial compared two SpO2 target regimens,91–94% versus 95–98%, in preterm infants born <30 weeksgestational age once they had reached a corrected age of32 weeks gestational age. This trial showed a significantincrease in bronchopulmonary dysplasia and home oxygentherapy in the high-saturation study arm but no differencein mortality or retinopathy of prematurity (4). Further con-trolled studies were lacking until recently. In 2010, the SUP-PORT trial revealed a moderate, though, significantincrease in mortality in extremely low gestational ageinfants when nursed in SpO2 targets of 85–89% versus 91–95% (5). Subsequently, the BOOST-II trials in the UK, Aus-tralia and New Zealand with a similar study design closedenrolment prematurely following a preliminary meta-analy-sis of their and the SUPPORT trial’s mortality data (6). Apooled analysis confirmed better survival in the higherSpO2 target group. Long-term outcome data are not avail-able yet.

We surveyed current practice of SpO2 targets and limitsin neonatal intensive care units (NICU) in Australia andNew Zealand 5 months after publication of the preliminarySUPPORT ⁄ BOOST-II meta-analysis. An email survey wassent to all 26 tertiary NICUs in Australia and New Zealandin September 2011. A reminder email was sent 3 weeks afterthe 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 afterpublication of the SUPPORT trial in May 2010?

• Did your unit change your SpO2 targets ⁄ limits after clo-sure of BOOST-II recruitment and communication of itspreliminary results in April 2011?

• If your unit changed SpO2 targets ⁄ limits, please specifyyour new SpO2 targets ⁄ limits.

• If your unit has not changed the SpO2 targets ⁄ limits, areyou considering a change, or will you keep your currentSpO2 targets ⁄ limits?

All survey participants consented their survey data to beused for publication. As the survey did not include anypatient data, ethics committee approval was not sought.Twenty (76.9%) completed surveys returned after thereminder email. Of those, 18 NICUs participated in theBOOST-II trial. None of the units changed their SpO2 tar-gets ⁄ limits after publication of the SUPPORT trial; however,eleven NICUs changed them following the communicationof the preliminary mortality analysis of the pooled SUP-PORT ⁄ BOOST-II data. Table 1 shows those NICUs thathave made changes to their SpO2 targets ⁄ limits; Table 2shows those that have not made any changes. Our survey,conducted 5 months after publication of the preliminarymeta-analysis, shows a rather scattered picture how tertiaryneonatal units in Australia and New Zealand managedSpO2 targets prior to the preliminary meta-analysis, andhow they responded to its results. Half of the NICUs usedSpO2 targets of 88–92% prior to SUPPORT ⁄ BOOST-II, arange exactly in the middle of the two trialled SpO2 rangesin SUPPORT ⁄ BOOST-II. However, some units used thistarget for all infants whereas others use higher targets forinfants above 31–32 weeks gestation, or for term infants.Five NICUs do not have defined SpO2 targets, and

Acta Pædiatrica ISSN 0803–5253

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therefore, only reported their SpO2 limits. The lowest lowerSpO2 limit was reported at 80%.

Eleven NICUs changed their SpO2 targets for all or sub-groups of their patient population since publication of thepreliminary meta-analysis. A similar degree of variation canbe seen. So far, only one unit limited the change in SpO2

target to preterm infants born less than 28 weeks gestation,according to the population of SUPPORT ⁄ BOOST-II. Onthe other hand, there are six NICUs that are considering achange on SpO2 targets ⁄ limits, but there is either

uncertainty about what new SpO2 ranges to choose, or finalstudy data including 2-year follow-up of SUP-PORT ⁄ BOOST-II are awaited. Three NICUs do not intendto change their current settings. Of note, one of theseNICUs already uses a 91–95% SpO2 target for preterminfants.

Our survey represents a snapshot of current practice in ahighly debated area of neonatal care. The response rate wasabove 75%, and the design included open- and close-endedquestions with room for comments. While the saturation

Table 2 SpO2 targets/limits of NICUs that have not made changes to their SpO2 targets/limits

SpO2 targets (limits) before SUPPORT ⁄ BOOST-II Comments

1 88–92% Considering change but not sure what targets ⁄ limits to use

2 88–92% (85–94%) for GA <37 weeks;

90–95% (88–100%) for GA ‡37 weeks

Considering new targets 90–95% for GA <36 weeks (new limits 89–96%)

3 88–92% (84–94%) Considering new targets 92–95% for GA ‡37 weeks (new limits 90–97%).

Awaiting meta-analysis before addressing preterm infants

4 No targets defined.

Limits: 86–94%Awaiting final study data

5 91–95% for preterm infants Will keep current targets

6 88–92% (85–94%) for GA <32 weeks; 89–94% (87–95%)for GA 33–36 weeks; 95–100% (93–100) for GA >

36 weeks, 89–94% (87–95%) for ex-GA <32 weeks

now corrected term

Will keep current targets

7 88–92% Will keep current targets

8 85–94% (82–95%) for GA <33 weeks or weight <2 kg;

92–96% (88–96%) for GA ‡33 weeks or weight ‡2 kg

Considering change but not sure what targets ⁄ limits to use

9 No targets defined.

Limits: 80–92% for GA <32 weeks;88–96% for GA ‡32 weeks

Awaiting final study data

Table 1 SpO2 targets/limits of NICUs that have made changes to their SpO2 targets/limits

SpO2 targets (limits) before SUPPORT ⁄ BOOST-II SpO2 targets (limits) after SUPPORT ⁄ BOOST-II

1 No targets defined

Limits: 86–94% for GA <37 weeks; 90–97% for GA ‡37 weeksNo targets defined

Limits: 90–96% for GA <37 weeks;93–98% for GA ‡37 weeks

2 88–92% for GA <32 weeks;

92–96% for GA ‡32 weeks

90–94% for all GA

3 90–95% (85–95% in acute phase, 83–97% in chronic phase)for GA <37 weeks;

>95% (>89%) for GA ‡37 weeks

90–95% (90–96%) for GA <37 weeks;

term unchanged

4 No targets defined

Limits: 85–93% for GA <32 weeks;88–95% for GA ‡32 weeks

89–93% (88–94%)

5 88–92% for all GA 90–95% for all GA

6 88–92% (86–94%) for GA <32 weeks;

88–92% if HMD or 94–97% if PPHN for GA ‡32 weeks;

90–95% for GA >36 weeks

88–92% (86–94%) for GA <32 weeks;

92–95% (90–96%) for GA ‡32 weeks,

95–98% (93–99%) for term infants with PPHN

7 No targets defined

Limits: 85–92% for GA <37 weeks;92–98% for term infants

91–95% (90–96%) for GA <37 weeks;

term infants unchanged

8 Condition dependent 88–92% for GA <35 weeks, 95–100% in PPHN

9 88–92% for GA <32 weeks;

92–96% for GA ‡32 weeks

91–95% (90–96%) for all GA

10 88–95% 88–94%

11 88–92% 91–95% (90–96%) for GA <28 weeks

Pulse oxygen saturation targets Konig and Holberton

e254 ª2012 The Author(s)/Acta Pædiatrica ª2012 Foundation Acta Pædiatrica 2012 101, pp. e253–e255

trials addressed SpO2 targets, we asked to state SpO2 targetsand ⁄ or limits as some units only use SpO2 limits. Weacknowledge the limitation of not having pretested thesurvey.

We conclude that tertiary NICUs in Australia and NewZealand show a high degree of variation in SpO2 targeting.Current evidence from randomized-controlled trials has notyet led to a uniform response.

CONFLICT OF INTERESTThe authors declare no conflict of interest.

FINANCIAL DISCLOSURENone.

AUTHORS’ CONTRIBUTIONSBoth authors designed the survey, analysed the data, andedited and approved the submitted version of the manu-script.

References

1. Tin W, Milligan DW, Pennefather P, Hey E. Pulse oximetry,severe retinopathy, and outcome at one year in babies of lessthan 28 weeks gestation. Arch Dis Child Fetal Neonatal Ed2001; 84: F106–10.

2. Chow LC, Wright KW, Sola A. Can changes in clinical practicedecrease the incidence of severe retinopathy of prematurity invery low birth weight infants? Pediatrics 2003; 111: 339–45.

3. Vanderveen DK, Mansfield TA, Eichenwald EC. Lower oxygensaturation alarm limits decrease the severity of retinopathy ofprematurity. J AAPOS 2006; 10: 445–8.

4. Askie LM, Henderson-Smart DJ, Irwig L, Simpson JM. Oxygen-saturation targets and outcomes in extremely preterm infants. NEngl J Med 2003; 349: 959–67.

5. Carlo WA, Finer NN, Walsh MC, Rich W, Gantz MG, LaptookAR, et al. Target ranges of oxygen saturation in extremely pre-term infants. N Engl J Med 2010; 362: 1959–69.

6. Stenson B, Brocklehurst P, Tarnow-Mordi W. Increased 36-week survival with high oxygen saturation target in extremelypreterm infants. N Engl J Med 2011; 364: 1680–2.

Konig and Holberton Pulse oxygen saturation targets

ª2012 The Author(s)/Acta Pædiatrica ª2012 Foundation Acta Pædiatrica 2012 101, pp. e253–e255 e255