Desenvolvimento de um novo aspirador de secreção pulmonar com oxigenação e umidificação

Abstract

The objective of this study is to design and assemble a new suction machine for endotracheal aspiration with oxygenation and humidification of the airways, low cost, easy to use, for open suctioning, residential or hospital use. The new suction machine intends to make the procedure safer and less uncomfortable for the patient and to facilitate the execution of the procedure that requires experience and skill of the professional who performs it. The new equipment allows the configuration of the suction mode which can be continuous or alternating, of the procedure time which cannot last longer than 15 seconds and in the case of the suction mode alternating the opened and closed vacuum time. With the humidification it is intended to fluidize the secretion and facilitate its removal, similarly to what occurs with the use of saline instillation, without the reduction in oxygenation and increased risk of infection that are related to this practice. With oxygenation it is intended to attenuate the risk of hypoxemia. offsetting the air which is inevitably removed from the patient's airway during the procedure. The fluid dynamics study within the one lumen catheter was performed using the Ansys Fluent program and validated by bench tests, to identify the important design points that lead to an efficient catheter and with less chance of patient injury. In this study, different pressures and mucus properties were considered. For the bench tests were used viscoelastics mucus simulators made from polyethylene glycol with molecular weight of 5,000,000 g/mol solutions, characterized by a TA Intruments ARG2 rheometer. The most significant pressure drop for the catheter is the distributed pressure drop, so the catheter should be as short as possible. However, when reduction of catheter length is no longer possible, larger areas for secretion entry, misaligned lateral orifices and fewer orifices increase catheter efficiency