A metered-dose inhaler (MDI) is a small, handheld device that uses a chemical propellant to deliver a dose of medication as an aerosol mist directly into the lungs. Achieving optimal medication delivery requires correct timing and technique, which can be challenging for many users. A spacer, often referred to as a valved holding chamber, is an accessory designed to improve the effectiveness of the MDI. This guide provides clear instructions for the proper use, function, and maintenance of this combination device.
Understanding the Spacer Device
A spacer is a tube-like attachment that connects to the MDI mouthpiece, creating a holding chamber for the aerosolized medication. When the inhaler is actuated, the drug is sprayed into this chamber, where the pressurized plume expands and slows down. This mechanism reduces the high velocity of the aerosol particles before they enter the user’s mouth and throat. By slowing the particles, the spacer minimizes the amount of medication that deposits on the back of the throat, known as oropharyngeal deposition. This reduction is particularly important for inhaled corticosteroids, as it lowers the risk of localized side effects like oral thrush. The spacer allows the medication to remain suspended in a fine mist, providing a larger window of time for the user to breathe the dose deeply into the lungs.
Step-by-Step Guide to Proper Usage
Before starting, remove the caps from both the inhaler and the spacer. Shake the MDI canister ten to fifteen times to ensure the medication and propellant are properly mixed. If the inhaler is new or has not been used for several weeks, it must be “primed” by spraying a few test puffs into the air, following the product’s specific instructions. Once prepared, firmly insert the canister end of the inhaler into the opening at the back of the spacer.
Sit or stand upright to allow for maximum lung expansion and exhale gently to empty your lungs completely, but do not exhale into the spacer. Place the spacer mouthpiece between your teeth and seal your lips tightly around it to prevent air from escaping. Press down once on the inhaler canister to release a single puff of medication into the chamber. Immediately begin a slow, deep inhalation through the mouthpiece.
The inhalation should be slow enough that the air is drawn in over three to five seconds, which maximizes the drug’s reach into the smaller airways. Some valved holding chambers include a whistle that will sound if the inhalation speed is too rapid, indicating that the medicine may be depositing too high in the respiratory tract. After fully inhaling, remove the spacer from your mouth and hold your breath for a count of five to ten seconds, if possible. This breath-holding period allows the fine aerosol particles to settle onto the walls of the airways.
Exhale slowly, then wait for one minute before taking a second puff, if one is prescribed. Repeat the entire process, starting with shaking the inhaler again, for any subsequent doses to ensure full delivery. A common mistake is failing to wait between puffs, which can reduce the effectiveness of the second dose. After using a corticosteroid inhaler, rinse your mouth with water, gargle, and spit the water out to reduce the risk of oral side effects.
Cleaning and Maintenance
Regular cleaning is necessary to prevent the buildup of medication residue and to maintain the device’s proper function. Spacers should typically be cleaned at least once a week, though some manufacturers may suggest more frequent cleaning. To clean the spacer, separate any removable parts and soak them in lukewarm water mixed with a mild liquid dishwashing detergent for about fifteen minutes. Avoid using hot or boiling water, as this can damage the plastic components.
After soaking, gently swish the parts in the soapy water and then remove them without rinsing. Rinsing can sometimes increase the static charge on the plastic, which causes medication to stick to the inner walls of the chamber. Shake off any excess water and allow all pieces to air dry completely in a vertical position on a clean surface. Do not use a cloth or paper towel to dry the inside of the spacer, as rubbing can also generate static charge.