The publication of a paper in Paediatric Critical Care Magazine in 2014 left SLE feeling very good about our ventilator technology. The paper entitled “Pressure and Flow Waveform Characteristics of Eight High-Frequency Oscillators” by Harcourt et al showed that the square wave produced by the SLE5000 was comparable to that produced by the original Sensormedics machine (suggesting potentially greater transmissive power to the lungs) when compared with the other ventilators on test.
This finding was reinforced by a later paper, “New Generation Neonatal High Frequency Ventilators: Effect of Oscillatory Frequency and Working Principles on Performance” published last year by Grazioli et al in Respiratory Care showed large variability in performance between five different HFO ventilators with three of the machines delivering lower Vt than the SLE5000 with the same pressure amplitude settings, both under pre-term and full-term infant settings. Since the CO2 elimination during HFOV is proportional to f·Vt the difference in performance may be even more significant in clinical settings. The discussion also went on to suggest that “The SLE5000 was the most powerful neonatal HFO ventilator in terms of volume delivery with a performance similar to that of the Sensormedics 3100A”.
This is all good news for SLE, and showed that our valveless technology and bidirectional jets allow us to deliver powerful, controlled breaths . However, perhaps the most telling data was in the discussion when it was summarised that all of the ventilators could deliver adequate oscillation to pre-term infants, but that not all of the ventilators could deliver adequate oscillation on term infants or larger babies. In addition, at higher frequencies (which we believe may become more popular during the next few years) some failed completely.
Both papers are worth a read and are good references as to why we believe SLE technology is the right route for HFO ventilation.
Chris Worrell, Marketing Manager