Manufacterer's recommendations:

The informative pamphlets [1] and [2] of the Optichamber recommend the following techniques: for the version with a mouthpiece, a slow and deep inhalation followed by an 8-second apnea; for the version with a mask, 5-6 breaths at tidal volume. Sometimes it is not possible to perform the technique adequately with a single deep inhalation, so it becomes relevant to use the technique of tidal volume breaths. It is important to note that the recommendations found are directed towards the version with a mask or without specifying the version. Therefore, caution is advised when interpreting them for the version with a mouthpiece of the Optichamber. Furthermore, it should be emphasized that regardless of the version used, proper timing is crucial, not delaying the start of breathing too much after pressing the inhaler; taking deep breaths, as shallow breaths at the start significantly reduce the effectiveness of inhalation; and effective sealing to avoid medication loss. [3], [4]

The Global Initiative for Asthma (GINA), in its 2022 report [5], mentions that "Generally, 5-10 breaths will be sufficient per actuation." The Global Initiative for Chronic Obstructive Lung Disease (GOLD) does not specify the number of inhalations to perform.

The American Academy of Allergy, Asthma, and Immunology recommends: "If a facemask is being used with a child or adult who cannot actively participate in medication-taking, hold the VHC with facemask in place for 6 full breaths [6]."

The UK Inhaler Group, which includes, among other organizations, the British Thoracic Society, advises: "Breathe in and out slowly and steadily into the spacer five times." [7]. The Canadian Thoracic Society advises: "Holding chambers with facemask attachments are useful for the elderly, who can use four to six tidal breaths for each actuation of the medicine "[8].

Although some other spacer devices recommend 2-3 breaths with the mouthpiece version, due to the absence of studies found and the lack of recommendation from the manufacturer in this regard, 5-6 breaths at tidal volume may be recommended.