Oxygen delivery using neonatal self-inflating resuscitation bags without a reservoir
- 1Neonatal Service, University Hospital Sant Joan de Déu, Barcelona, Spain
- 2Neonatal Services, The Royal Women's Hospital, Melbourne, Australia
- 3Departments of Obstetrics and Gynaecology, University of Melbourne, Australia
- 4Murdoch Children's Research Institute, Melbourne, Australia
- Correspondence to Marta Thió, Newborn Research, The Royal Women's Hospital, Locked Bag 300, Cnr Grattan St and Flemington Road, Parkville, VIC 3052, Australia; mthio{at}hsjdbcn.org
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Contributors M Thió designed the study, carried out the experiments, analysed the data and wrote the manuscript. R Bhatia assisted with the experiments and contributed to the preparation of the manuscript. JA Dawson contributed to study design, statistical analysis and manuscript preparation. PG Davis supervised all stages of the study design, carrying out the experiments and preparation of the manuscript.
- Accepted 3 September 2009
- Published Online First 19 October 2009
Abstract
Background Guidelines recommend avoidance of excessive oxygen administration during neonatal resuscitation. Blenders are used in some but not all hospitals. It has been suggested that self-inflating bags without a reservoir deliver around 40% oxygen and could be used to provide an inexpensive and effective technique of avoiding oxygen toxicity.
Objective To explore how much oxygen is delivered when using two different brands of neonatal self-inflating resuscitation bags without a reservoir.
Methods In a benchtop setting, the smallest non-disposable self-inflating bags from the Laerdal and Ambu ranges were tested. Oxygen concentration delivered by these devices under a variety of conditions was measured. 108 combinations of oxygen flow rates (10; 5 to 1 litre/min), ventilation rates (30, 60, 100 inflations/min) and peak inspiratory pressure ranges (20 to 25 cm H2O, 35 to 40 cm H2O or pop-off valve range, 55 to 60 cm H2O) were tested.
Results Delivered oxygen concentration varied depending on three parameters: gas flow rate, ventilatory rate and pressure. At a pressure of 20 to 25 cm H2O, mean oxygen concentration delivered by both bags exceeded 70% at any gas flow rate except for 1 litre/min (where delivered oxygen concentration was 60% to 70%). When the pop-off valve was opened at 35 to 40 cm H20, oxygen concentrations fell to 30% to 45% at gas flow rates ≤2 litres/min. The Ambu bag delivered a lower oxygen concentration than the Laerdal bag but this difference was not clinically important.
Conclusion When using the Laerdal and Ambu infant resuscitation self-inflating bags without a reservoir, delivered oxygen concentration is >70% for currently recommended flow and pressure settings.
Footnotes
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Competing interests None.
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Provenance and peer review Not commissioned; externally peer reviewed.
- Accepted 3 September 2009
- Published Online First 19 October 2009
