CHARACTERISTIC OF VENTURI SYSTEMS FOR OXYGEN APPLICATION AT VARIOUS FLOW RATES AND LOADS

Teoretično izhodišče. Venturi maske so sistemi z visokim pretokom, ki dovajajo natančno vrednost kisika v vdihanem zraku (FIO2). V študiji smo analizirali vpliv različnih pretokov in nastavkov na skupni pretok in na FIO2. Metodologija raziskovanja. Kvanitiativna eksperimentalna študija je potekala na simulatorju meti HPS. Uporabljali smo 24 %, do 60 % Venturi nastavke. Pretoke smo merili z aparatom Fluke VT plus HP analizator plinov. Delež kisika med inspirijem in med ekspirijem pa z anestezijskim aparatom Draeger Primus. Rezultati raziskave. Ugotavljamo, da so problematični pretoki, ki so pod deklariranim. V teh primerih Venturi ne dovaja vrednosti FIO2. Pri višjih pretokih od deklariranih pa ostaja FIO2 stabilen, razen pri Venturi 24 %. Podaljšek vpliva na Venturi na način, da so skupni pretoki nekoliko manjši zaradi obremenitve samega Venturi nastavka. Pri 24 % Venturi nastavku opazimo zmanjšanje skupnega pretoka iz 34 l/min na 23 l/min. Pri zamašitvi stranske luknje Venturi nastavka pa smo opazili padec skupnega pretoka skozi Venturi. Sklep. Ugotovili smo, če nastavimo nedeklariran pretok kisika, kot je označeno na Venturi nastavku, ostaja odstotek kisika v vdihanem zraku nespremenjen, sam pretok pa se povečuje. Pri zamašitvi odprtin skozi Venturi nastavek je najbolj opazna sprememba pri zamašitvi dveh odprtin, saj se poveča delež kisika v vdihanem zraku.Theoretical basis. Venturi masks are high-flow systems which supply an exact value of oxygen in the inspired air (FIO2). This study analysed the influence of different flow and supplements on a common flow and on FIO2. Methodical approach. Qualitative experimental study was processed on the simulator meti HPS. A variety of Venturi supplements were used, from 24 % to 60 %. The flow was measured with the Fluke VT apparatus and the HP gas analyzer. The amount of oxygen while inhaling and exhaling was measured with the anesty apparatus Draeger Primus. Research outcome. We ascertained that oxygen flows rates which are beneath the declared ones, are extra problematic. In these cases Venturi does not supply the amount of FIO2. However, the amount of FIO2 is stable among the flows that are higher from the declared ones, except if Venturi is 24 %. The extension influences the Venturi, so that the common flows are slightly reduced because of the Venturi device\u27s burden. We notice the reduction of a common flow from 34 l/min in to 23 l/min under the 24 % Venturi supplement. The partial obstruction of the air- entrainment ports of Venturi device lead to the drop of a common flow through Venturi. Conclusion. We established that under the unprofessed flow of oxygen, as marked on Venturi device, the amount/percentage of oxygen in the inspired air stays unvaried, the flow is but increased. If we obturate orifices through Venturi device, an evident change can be observed under the obturation of both orifices, as the amount of oxygen in the inspired air increases