%0 Generic %A R.P., Neumann %A J.J., Pillow %A C., Thamrin %A A.N., Larcombe %A G.L., Hall %A S.M., Schulzke %D 2017 %T Supplementary Material for: Influence of Gestational Age on Dead Space and Alveolar Ventilation in Preterm Infants Ventilated with Volume Guarantee %U https://karger.figshare.com/articles/dataset/Supplementary_Material_for_Influence_of_Gestational_Age_on_Dead_Space_and_Alveolar_Ventilation_in_Preterm_Infants_Ventilated_with_Volume_Guarantee/4702672 %R 10.6084/m9.figshare.4702672.v1 %2 https://karger.figshare.com/ndownloader/files/7677043 %2 https://karger.figshare.com/ndownloader/files/7677046 %2 https://karger.figshare.com/ndownloader/files/7677049 %K Very-low birth weight infants %K Premature infants %K Tidal volume %K Artificial respiration %X

Background: Ventilated preterm infant lungs are vulnerable to overdistension and underinflation. The optimal ventilator-delivered tidal volume (VT) in these infants is unknown and may depend on the extent of alveolarisation at birth. Objectives: We aimed to calculate respiratory dead space (VD) from the molar mass (MM) signal of an ultrasonic flowmeter (VD,MM) in very preterm infants on volume-targeted ventilation (VT target, 4-5 ml/kg) and to study the association between gestational age (GA) and VD,MM-to-VT ratio (VD,MM/VT), alveolar tidal volume (VA) and alveolar minute volume (AMV). Methods: This was a single-centre, prospective, observational, cohort study in a neonatal intensive care unit. Tidal breathing analysis was performed in ventilated very preterm infants (GA range 23-32 weeks) on day 1 of life. Results: Valid measurements were obtained in 43/51 (87%) infants. Tidal breathing variables were analysed using multivariable linear regression. VD,MM/VT was negatively associated with GA after adjusting for birth weight Z score (p < 0.001, R2 = 0.26). This association was primarily influenced by the appliance dead space. Despite similar VT/kg and VA/kg across all studied infants, respiratory rate and AMV/kg increased with GA. Conclusions:VD,app rather than anatomical VD is the major factor influencing increased VD,MM/VT at a younger GA. A volume guarantee setting of 4-5 ml/kg in the Dräger Babylog® 8000 plus ventilator may be inappropriate as a universal target across the GA range of 23-32 weeks. Differences between measured and set VT and the dependence of this difference on GA require further investigation.

%I Karger Publishers