100% oxygen is the commonly recommended gas for the resuscitation of infants at birth. There is growing evidence from both animal and human studies that room air is as effective as 100% oxygen and that 100% oxygen may have adverse effects on breathing physiology and cerebral circulation. There is also the theoretical risk of tissue damage due to free oxygen radicals when 100% oxygen is given. The use of room air has, therefore, been suggested as a safer and possibly more effective alternative.
In newborn infants requiring resuscitation, does the use of room air reduce the incidence of death, neurological disability and short term morbidity when compared with the use of 100% oxygen?
This included searches of the Oxford Database of Perinatal Trials, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2004) and MEDLINE PubMed 1966 to December 2003, and handsearches of reference lists of relevant articles and conference proceedings.
All randomised and quasi-randomised studies comparing the use of room air or any other concentration of oxygen versus 100% oxygen in the resuscitation of infants at birth.
Data collection and analysis
Three authors assessed the methodological quality of eligible trials and extracted data independently. When appropriate, meta-analysis was conducted to provide a pooled estimate of effect. For categorical data the relative risk (RR), risk difference (RD) and number needed to treat (NNT) with 95% confidence intervals (CI) were calculated. Continuous data were analysed using weighted mean difference (WMD).
Five studies were identified which enrolled a total of 1302 infants. In two studies allocation was randomised and the caregivers were blinded to intervention group. In the other three studies, allocation was quasi-randomised and the caregivers were not blinded. Pooled analysis of the four trials reporting effect on death showed a significant reduction in the rate of death in the group resuscitated with room air [typical RR 0.71 (0.54, 0.94), typical RD -0.05 (-0.08, -0.01), NNT 20 (12, 100)]. There were no significant differences between the groups with respect to rates of grade 2 or 3 hypoxic ischaemic encephalopathy. One of the four trials reported a statistically significant difference in median 5 minute Apgar scores, favouring the group allocated to room air. However, the absolute difference between the medians was small and there were no significant differences in the median 10 minute Apgar scores in the three trials reporting this outcome.
One trial followed up a selected subgroup of survivors to 18-24 months. There were no significant differences in rates of adverse neurodevelopmental outcomes including cerebral palsy and failure to achieve various milestones; however, the proportion of eligible patients seen was less than 70%.
Analyses that were planned for this review, but not able to be carried out because of lack of published data, included a sub-analysis stratified by gestational age and assessments of the effect on bronchopulmonary dysplasia and retinopathy of prematurity.
There is insufficient evidence at present on which to recommend a policy of using room air over 100% oxygen, or vice versa, for newborn resuscitation. A reduction in mortality has been seen in infants resuscitated with room air, and no evidence of harm has been demonstrated. However, the small number of identified studies and their methodologic limitations dictate caution in interpreting and applying these results. We note the use of back-up 100% oxygen in more than a quarter of infants randomised to room air. Therefore, on the basis of currently available evidence, if one chooses room air as the initial gas for resuscitation, supplementary oxygen should continue to be made available.
其中確定了五項研究共招收1302位嬰兒。在兩項研究的分配是隨機的且照顧者對干預組是blinded。在其他三項研究，分配是半隨機且照顧者是沒有blinded。匯總分析四項試驗報告了使用室內空氣做復甦對死亡率有顯著減少 [typical RR 0.71 (0.54, 0.94), typical RD −0.05 (−0.08, −0.01), NNT 20 (12, 100)]。就2級或3級缺氧缺血性腦病組沒有顯著差異。四個研究的其中一個，在五分鐘的Apgar分數中位數在室內空氣組較佳，但絕對值的差異很小，同時在另外三個報導10分鐘Apgar分數的研究中，均未顯出差異。一個試驗還追蹤了18 – 24個月倖存者次分組。在以下幾個神經發育不良後果都沒有顯著差異包括腦性麻痺，未能達到發展目標里程碑，符合條件的患者被追蹤比例低於70%。由於缺乏公佈的數據而無法進行的包括由胎齡分層次分析和評估對支氣管肺發育不良和早產兒視網膜病變的影響。。
此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。