Conditioning of Air in Mechanically Ventilated Patients
The main purposes of the upper airways are warming, humidifying and filtering the inspired air. The mechanisms of filtration and heat and moisture exchange between mucosa and ventilated air are sufficient even under extreme atmospheric conditions. However, artificial conditioning of the inspired air is necessary in intubated patients due to the elimination of the functions of the upper airways by the endotracheal tube. The isothermic saturation border moves from the lower part of the trachea to areas distal to the pulmonary bifurcation. Warming, humidification, and filtration of the inspired air is shifted towards areas of the bronchial system which are not appropriate for these functions. Morphological damage to the sensitive respiratory epithelium are inevitable if no effective conditioning of the inspired air is provided. Therefore, measures to maintain or restore the physiological condition of air in the airways are necessary immediately subsequent to intubation.
KeywordsCatheter Filtration Total Heat Lithium Foam
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