Juan Luis Larrabe

Surfactant and Perfluorocarbon Aerosolization by Means of Inhalation Catheters for the Treatment of Respiratory Distress Syndrome: An In Vitro Study

BACKGROUND The aerosolization of perfluorocarbons or surfactant has emerged as a feasible alternative to instillation, for the treatment of experimental respiratory distress syndrome. However, the biophysical properties that make these compounds useful in such therapies, significantly affect the performance of nebulizers. Therefore, in vitro studies are required to assess the suitability of new aerosolization technologies for use with these compounds. METHODS The aim of the present in vitro study was to investigate the influence of the biophysical properties of perfluorocarbons (PFD, FC75, and PFOB) and a natural porcine surfactant, Curosurf®; on aerosolization and to assess the suitability of three intratracheal inhalation catheters (IC) with different air flow rates (IC-1.23, IC-1.1, IC-1.4) coupled to a jet nebulizer, for aerosol delivery of these compounds. RESULTS With IC-1.23 significantly higher aerosol production rates were achieved (p < 0.0001), ranging between 6.05 ± 0.17 mL/min (FC75) and 1.94 ± 0.09 mL/min (Curosurf®), and lower percentage losses of the compound (5-21%), compared to IC-1.1 and IC-1.4 catheters. The lowest aerosolization rates were produced with IC-1.4 ranging from 0.58 ± 0.02 mL/min (FC75) to 0.14 ± 0.01 mL/min (Curosurf®), and this catheter also resulted in the highest percentage losses (25-60%). The mass median aerodynamic diameter (MMAD) ranged between 0.77 μm (PFD) and 8.29 μm (Curosurf®) with IC-1.1, whereas higher MMAD values, of between 4.84 μm (FC75) and 13.42 μm (PFOB), were observed with IC-1.23. Regardless of the catheter used during aerosolization, the perfluorocarbon with the highest kinematic viscosity showed the lowest aerosolization and emission rates and vice versa, which reveals the substantial contribution of this parameter that should accordingly be considered in the design of perfluorocarbon aerosol drug delivery systems. CONCLUSIONS Jet aerosolization of perfluorocarbons or surfactant with the intratracheal inhalation catheters seems to be a suitable method for treating experimental respiratory distress syndrome, because it delivers relatively high doses of perfluorocarbons and surfactant to the lungs in a respirable size droplets.

Support making decision using Hotelling T 2 technique in an undersea natural gas storage plant

A method to support making decision in a undersea natural gas storage plant using Hotelling T2 is showed in this paper. The stationery work in this manufacture facilities during a few moths in a year involve a heavy duty service of gas diesel engines and ammonia gas plant for processing the methane gas and extract the condensate fluid of it. Then, a predictive maintenance plan is necessary to prevent a possible malfunction or shut down of the plant and avoid an operational cost increased. We are just sampling the signals from the plant when its working in optimal condition and then we will compare the next incoming data from the machinery versus the previous historical data set. An statistical process control algorithm Hotelling T2 based for monitoring the condition of gas engines and ammonia gas plant will be implemented.

Telediagnosis and maintenance of the ship from land, using principal component analysis to compress acquired data offshore

At sea, voice and data communications have virtually global coverage via satellite. Satellite communications are increasing the bandwidth and lowering the cost, but are still far from levels that are in earth. The Principal components analysis (PCA) is a statistical technique used for lossy or non exact compression data; is a common tool for the search of pattern of multidimensional data sets. The assertion of this study was the possibility of using the PCA theory to compress, with sufficient accuracy, the large amount of data that are collected on board, and then send them all via satellite, in a cheaper or/and faster way than traditionally. This strategy is appropriate for decision making about telediagnosis and maintenance of the ship using ground equipment. Consequently, significant savings are achieved in telecommunication costs and telecommunication times.