Reference — Aerosol Therapy & Pharmacology
Aerosol Device Quick Reference
The aerosol delivery devices side by side — pMDI, pMDI with a spacer, DPI, small-volume nebulizer, and soft-mist inhaler — with the inhalation technique each demands and the advantages and limitations that decide which one fits the patient.
Written by Apex Respiratory Editorial Team
Educational use only. This material supports respiratory therapy education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional protocols, or physician orders. Always follow facility policies and current provider orders, and verify calculations independently before clinical use.
Overview
Every aerosol device delivers a respirable aerosol, but each demands a different inhalation maneuver and carries different trade-offs. The choice turns on what the patient can actually do — their inspiratory ability and acuity — not on the device alone. This table sets the devices side by side with the technique, advantages, and limitations of each so the match to the patient is quick to make.
Devices at a Glance
| Device | Technique | Advantages | Limitations / Cautions |
|---|---|---|---|
| pMDI | Slow deep breath; actuate at the start; 10-second hold | Portable, fast, multidose | Requires coordination; high oropharyngeal deposition without a spacer |
| pMDI + spacer / VHC | Slow deep breath after actuation (or tidal with a mask) | Less coordination, less oropharyngeal deposition, good for children and acute use | Bulkier; keep clean to limit static |
| DPI | Fast, forceful, deep breath | Breath-actuated (no hand-breath coordination), no propellant | Needs high inspiratory flow (> 60 L/min); not for severe distress or young children; humidity clumps the powder |
| SVN (small-volume nebulizer) | Normal tidal breathing | Easy, delivers high doses, no coordination, can run with oxygen | Slower, needs equipment/power, infection risk, less portable |
| SMI (soft mist inhaler) | Slow deep breath of the slow mist | Slow-moving mist with high lung deposition, less coordination than a pMDI | Multi-step preparation |
Clinical Notes
- Match the device to ability and acuity. Choose on the patient’s inspiratory ability and how acutely ill they are — not on the device’s features in isolation.
- A DPI is useless without adequate inspiratory flow. No fast, forceful breath means no de-aggregation and no respirable dose — rule it out when the patient cannot generate the flow.
- Use a spacer with every inhaled corticosteroid. It raises respirable delivery and cuts the oropharyngeal deposition behind thrush and dysphonia.
- Verify technique at every encounter. Technique drifts; watch the patient perform the maneuver rather than assuming the last lesson held.
- Favor a nebulizer or pMDI-plus-spacer in acute distress. Both run on tidal breathing and need no precise coordination, so they are the safer choice when the patient is acutely short of breath.
Related Resources
Sources
- Kacmarek RM, Stoller JK, Heuer AJ. Egan's Fundamentals of Respiratory Care. 12th ed. Elsevier; 2021.
- Gardenhire DS. Rau's Respiratory Care Pharmacology. 10th ed. Elsevier; 2019.