This study aimed to use a lamb model of preterm birth to investigate the impact of different bias gas flow strategies, applied during positive pressure ventilation, on lung injury development. Preterm lambs were ventilated for a total of 90 minutes. A group of lambs was euthanised at birth to act as an unventilated control group. At post-mortem lung tissue was sampled for proteomic analysis. Lung tissue samples were analysed by mass spectrometry-based proteomics using a TMT-11plex labelling approach, followed by nano-liquid chromatography coupled to an Eclipse Orbitrap mass spectrometer in a data-dependent acquisition mode.