In Vitro Surfactant and Perfluorocarbon Aerosol Deposition in a Neonatal Physical Model of the Upper Conducting Airways

Objective: Aerosol delivery holds potential to release surfactant or perfluorocarbon (PFC) to the lungs of neonates with respiratory distress syndrome with minimal airway manipulation. Nevertheless, lung deposition in neonates tends to be very low due to extremely low lung volumes, narrow airways and high respiratory rates. In the present study, the feasibility of enhancing lung deposition by intracorporeal delivery of aerosols was investigated using a physical model of neonatal conducting airways. Methods: The main characteristics of the surfactant and PFC aerosols produced by a nebulization system, including the distal air pressure and air flow rate, liquid flow rate and mass median aerodynamic diameter (MMAD), were measured at different driving pressures (4-7 bar). Then, a three-dimensional model of the upper conducting airways of a neonate was manufactured by rapid prototyping and a deposition study was conducted. Results: The nebulization system produced relatively large amounts of aerosol ranging between 0.3 +/- 0.0 ml/min for surfactant at a driving pressure of 4 bar, and 2.0 +/- 0.1 ml/min for distilled water (H(2)Od) at 6 bar, with MMADs between 2.61 +/- 0.1 mu m for PFD at 7 bar and 10.18 +/- 0.4 mu m for FC-75 at 6 bar. The deposition study showed that for surfactant and H(2)Od aerosols, the highest percentage of the aerosolized mass (similar to 65%) was collected beyond the third generation of branching in the airway model. The use of this delivery system in combination with continuous positive airway pressure set at 5 cmH(2)O only increased total airway pressure by 1.59 cmH(2)O at the highest driving pressure (7 bar). Conclusion: This aerosol generating system has the potential to deliver relatively large amounts of surfactant and PFC beyond the third generation of branching in a neonatal airway model with minimal alteration of pre-set respiratory support.

Jarduera Autonomoa: 2 urteko gelan

Laburpena: Emmi-Pikler eta Pikler-Lóczy Institutuaren hezkuntza eredu arrakastatsua oinarritzat harturik, 2 urteko haurren jarduera autonomoaren bilakaera behatu da. Jarduera autonomoari lekua eskaintzen ez zitzaion ekintza batean lekua utziz, hezitzaileok esku hartze zuzena txikituz eta haurrei lekua eginez. Jantokira joateko atontze unean brusa jantzi, botoiak lotu eta adurretakoa janzteko izan duten gaitasuna behatu da. Azterturiko arlo guztietan haurrek izandako bilakaera positiboa eta sortu den lankidetza giroa ikusirik jarduera autonomoak fruituak eman dituela esan dezakegu. Hezitzaile eta helduon esku dago haurrak jarduera autonomora bidean lagundu eta berau garatzeko baldintza egokiak sortzea, lorpenak aitortzea, etengabeko feedback positiboan. Haurrek ezarritako helburu eta erritmo desberdinak onartuz.

Use of generalised additive models to categorise continuous variables in clinical prediction

13 P.