- MDI: 9%
- MDI with spacer 15%
- SVN: 12%
- DPI: 13%
According to MacIntyre, "Aerosolized delivery in intubated, mechanically ventilated patients," Critical Care Medicine, 1885 (13, 81), the amount of inhaled medicine that gets to the air passages of an intubated patient is even less, about 2.9 percent. This information is according to James Fink.
This is interesting. You can see clearly here that more medicine as a percentage that is taken reaches the lungs of a patient using an MDI with a spacer compared to that of an SVN and even a DPI.
However, we must also consider how much medicine is given. A typical SVN provides 2.5mg of a solution, which is usually twice the amount of medication as 2 puffs, or 200 micrograms (μg) of albuterol.
Still, even while there is more medicine delivered with an SVN, the 2 puffs generated similar results as the SVN. This is interesting. And I imagine this is the proof many hospitals have used in changing to using MDIs in the stead of SVNs.
Also, an MDI is much less expensive than an SVN.
- Hess, Dean, Neil MacIntyre, Shelley Mishoe, William Galvin, editors, "Respiratory Care Principles and practice," 2nd edition, 2012, Jones and Bartlett, page 316