A spacer is a tube-shaped attachment used with a metered-dose inhaler (MDI), often called a puffer, to make medication administration simpler and more efficient. This device creates a chamber between the MDI and the patient’s mouth, acting as a holding area for the aerosolized medicine. The primary purpose is to improve drug delivery to the lungs, where it is needed to manage respiratory conditions. By using a spacer, the process of inhaling the medication becomes less dependent on the user’s timing and technique, making the MDI more effective for a wide range of people, including children and those with coordination difficulties.
How Spacers Improve Inhaler Effectiveness
The MDI delivers medication as a high-velocity spray, traveling up to 60 miles per hour. This rapid speed causes medication particles to impact and deposit in the back of the throat and mouth, a process called oropharyngeal deposition. Swallowed medicine provides little therapeutic benefit to the lungs and may cause side effects. The spacer solves this by slowing the aerosol speed before it enters the mouth.
The expanded volume allows the medication’s solvent to evaporate, reducing the size and weight of the remaining drug particles. Smaller, lighter particles can be inhaled more easily and travel deeper into the lower airways, significantly increasing the fraction of the drug that reaches the lungs. This improved lung deposition can increase the medication reaching the airways by two to four times compared to using an MDI alone. The spacer also eliminates the need for precise hand-breath coordination, which is challenging when users must simultaneously press the canister and inhale deeply.
Many spacers are designed as valved holding chambers (VHCs), featuring a one-way valve at the mouthpiece. This specialized valve traps the medication inside the chamber for several seconds after the MDI is fired, allowing the user to take multiple, slower breaths to ensure the medicine is fully inhaled. The valve prevents the user from accidentally exhaling back into the chamber, which could push the medication out. This feature benefits those who cannot take a single, slow, deep breath, or young children using a face mask attachment.
Detailed Instructions for Use
Proper technique begins by removing the caps from the inhaler and spacer, then shaking the MDI for three to five seconds to ensure the medicine and propellant are mixed. Insert the metal canister into the soft opening at the back of the spacer, ensuring the inhaler remains upright. Before taking the dose, breathe out gently, pushing as much air out of the lungs as possible, away from the spacer.
Place the spacer mouthpiece between the teeth, forming a tight seal with the lips. Release a single dose into the chamber by pressing down once on the MDI canister. Immediately after firing the dose, breathe in slowly and deeply through the mouth. The inhalation should take about five seconds, ensuring a steady, slow flow of air.
After taking a full breath, remove the spacer and hold your breath for five to ten seconds; this allows the medication particles to settle deep within the lungs. If a second puff is required, wait 15 to 30 seconds, shake the inhaler again, and repeat the process. For infants, toddlers, or others unable to form a seal, use a mask attachment placed firmly over the nose and mouth. The child should then take six slow breaths from the chamber.
Device Care and Longevity
Regular cleaning is necessary because medication accumulates on the inner walls and valve of the spacer over time. This residue increases the static electrical charge inside the chamber, causing subsequent doses to stick to the plastic instead of remaining suspended. Cleaning should be done at least once a week, or as directed by the manufacturer.
The recommended cleaning method involves taking the spacer apart and washing the pieces gently in warm water mixed with a mild liquid dishwashing detergent. Do not scrub the inside of the spacer, as this can damage the anti-static coating present in some devices. After washing, allow the parts to air-dry completely without rinsing; the small film of detergent residue helps prevent static buildup. Replace the spacer if it shows signs of damage (such as cracks) or if the valve becomes stiff or brittle. Manufacturers recommend replacing the device after six to twelve months of regular use to maintain optimal performance.
Addressing Common User Concerns
A frequent concern is the high-pitched whistling sound some spacers produce during inhalation. This sound is an intentional warning, indicating the user is breathing in too quickly. If the whistle is heard, immediately slow down inhalation speed to ensure medication reaches the lungs effectively rather than impacting the throat. The chamber’s specific volume is necessary to allow aerosol particles to slow down and the propellant to fully evaporate, addressing concerns about the spacer’s bulkiness.
Users may notice a fine, white residue or cloudiness inside the chamber, which is accumulated medication and propellant residue. This is normal and is the reason for the weekly cleaning routine. For storage, keep the spacer away from excessive heat and dust. If the valve appears damaged or the body is cracked, the spacer must be replaced, as a damaged unit will not function correctly and may compromise drug delivery.