Inhaled medication delivery to infants via valved holding chamber with facemask: Not all VHCs perform the same
Bibliographic record
Abstract
RATIONALE: We report a study using an in-vitro model (ADAM-III) in which the structure of a 7 month infant face together with an anatomically accurate nasopharynx have been simulated. This model was used to test two VHC-facemask products (antistatic AeroChamber Plus® with Flow-Vu® inspiratory flow indicator (aAC Plus/IFI), TMI; A2A Spacer, Clement Clarke International) with a beta 2 adrenergic agonist pMDI. METHODS: Each VHC (n=5 devices/group) was tested out-of-package, and the A2A spacer group were also tested after pre-washing with detergent to mitigate electrostatic charge. A filter at the distal end of the nasopharynx model collected aerosol capable of reaching the lungs. Test conditions included a tidal volume of 50 mL, inspiratory/expiratory ratio of 1:3 and 30 breaths/min. 5-actuations of salbutamol sulfate (90 µg/actuation) were delivered at 30-s intervals, timing each actuation to coincide with (a) onset of inhalation (coordinated) and (b) the onset of exhalation (uncoordinated). The mass of salbutamol was recovered from the filter to determine delivered mass/actuation ( DM ). RESULTS: DM ex aAC Plus/IFI VHC group was significantly greater than from the A2A spacer devices, even after pre-washing the latter devices (unpaired t-test, p < 0.001). Additionally, DM ex A2A Spacer markedly decreased when pMDI actuation coincided with exhalation (paired t-test, p < 0.001), whereas the corresponding values from the aAC Plus/IFI VHC group were unaffected (p = 0.75). CONCLUSIONS: The delivered mass from the two VHCs differed significantly as did the relationship with onset of inhalation. Clinicians should be aware of these differences and their potential clinical impact.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".