Background: Gases for respiratory support at birth are typically ‘cold and dry', which may increase the risk of hypothermia and lung injury. Objectives: To determine the feasibility of using heated humidification from birth. Method: A humidifier targeting 37°C, a manual-fill chamber and a Neopuff Infant T-piece resuscitator and circuit were attached to a face mask and a manikin. Recordings using 20 ml H2O for humidification and a flow of 10 l/min were undertaken. Temperature and relative humidity (RH) were recorded. Additional recordings were made, each with one alteration to baseline (50 ml H2O for humidification, auto-fill chamber, a flow of 8 l/min, addition of circuit extension piece, warmed humidification H2O, increased ambient temperature and targeting 31°C). The duration of heated humidification and the response to disconnecting the power were investigated. Results: The baseline circuit achieved 95% RH and 31°C in 3 min, >99% RH in 7 min and ≥35°C in 9 min. No circuit alterations resulted in faster gas conditioning. The extended length circuit and targeting 31°C reduced the maximum temperature achieved. A flow of 8 l/min resulted in slower heating and humidification. The baseline circuit delivered heated humidification for 39 min. Without power, the temperature and humidity fell below international standards in 3 min. Conclusion: Rapid gas conditioning for newborn stabilisation is feasible using the experimental set-up, ≥20 ml H2O and a flow of 10 l/min. The circuit could be used immediately once switched on. Without power, conditioning is quickly lost. Investigation of the clinical effects of gas conditioning is warranted.

Keywords:
Humidification, Gas conditioning, Newborn stabilisation, Respiratory support
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© 2014 S. Karger AG, Basel
2014
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