Droplets Produced by Medical Nebulizers: Results (Part 1)
The fall in temperature with time of nebulization for each of the nebulizer-generator systems is shown in Figure 1. For the jet nebulizers, the temperature falls to a steady value Ts which is 5 to 6°C below the ambient temperature at the lower flow rates of the air compressors, and 11 to 15°C at 8 L/min flow rate from a gas cylinder. Most of this temperature change occurs in the first 4 min of aerosol generation. By contrast, the ultrasonic nebulizer increases in temperature by approximately 18°C and over a longer period of time (approximately 20 min [Fig 2]).
The total outputs of the jet nebulizer systems are plotted against generation time in Figure 3. The total output fell during nebulization for all of the jet nebulizer systems tested. The magnitude of the fall was similar for both the Cadema and Up-Draft with reductions in total output of approximately 45 to 65 mg/min for temperature falls of 11 to 15°C (over 6 min of generation). asthma inhalers
The reduction in output with generation time for the two air compressor-driven systems was lower; approximately 15 and 27 mg/min for the Aerosol-One and the Flatus, respectively, after a temperature fall of 5 to 7°C during 6 min of generation.
Figure 1. Graph of nebulizer solution temperature below ambient (23 to 24°C) vs time of generation for the four jet nebulizer systems: Up-Draft/Aerosol-One (squares), Up-Draft/Flatus (diamonds), Ca-dema/compressed oxygen (circles) and Up-Draft/compressed oxygen (triangles).
Figure 2. Graph of nebulizer solution temperature vs generation time for the Mist-02-Gen ultrasonic nebulizer.
Figure 3. Graph of nebulizer output vs generation time for the four jet-nebulizer systems: Up-Draft/Aerosol-One (squares), Up-Draft/ Flatus (diamonds), Cadema/compressed oxygen (circles) and UpDraft/compressed oxygen (triangles).