[The Oxytron: a new device for administering oxygen in the spontaneously breathing patient]

The Oxytron (Weinmann, Hamburg, FRG) electronic oxygen conserver (patent pending) is a new device designed to deliver precise amounts of oxygen at the optimum point in the breathing cycle via a nasal cannula. In 200 Oxytron the delivered volume of oxygen was 35 +/- 5 ml within 150-200 ms at the beginning of the inspiratory phase of the respiratory cycle. Four different settings are possible: setting 1 provides one insufflation every 4th breath; setting 2 provides one insufflation every 2nd breath; setting 3 provides three insufflations every 4 breaths; and setting 4 provides an insufflation with every breath. These settings provide approx. The equivalent of 1-4 l oxygen per minute on a continuous flow basis. Both clinical experience and literature reports show variations in savings, with an average ratio of approx. 6:1 to 7:1. In the clinical evaluation, the following advantages were found: easy handling, exact oxygen delivery, increased oxygen saving and increased oxygen delivery with increasing respiratory rate. Due to the lack of any alarm system monitoring disconnection or failure of oxygen supply must be considered a disadvantage.