An inhaler spacer, often referred to as a valved holding chamber (VHC), is a simple, tube-shaped medical device designed to improve the effectiveness of a metered-dose inhaler (MDI). The spacer attaches to the inhaler on one end and features a mouthpiece or mask on the other, creating a reservoir for the aerosolized medication. This holding action helps patients, particularly children or those who struggle with coordination, use their inhalers more effectively. By simplifying the technique, the spacer ensures a greater amount of medicine reaches the lungs where it is needed for respiratory conditions like asthma or chronic obstructive pulmonary disease.
Where and How to Acquire a Spacer
The accessibility of inhaler spacers is divided: some models are available over the counter (OTC), while others require a prescription. Basic, non-valved tube spacers or generic valved holding chambers can often be purchased directly from a pharmacy. These OTC options provide a quick solution for patients who need a device immediately or who prefer to pay out of pocket.
However, many high-quality, brand-name valved holding chambers (VHCs) are frequently managed through a prescription. Requiring a prescription ensures the specific device is medically appropriate, particularly for those needing anti-static properties or specialized masks. Furthermore, obtaining a prescription is often necessary to ensure the cost of the spacer is covered by medical insurance, which significantly reduces the patient’s expense.
Acquisition methods vary depending on local regulations and the specific type of device. A prescription may be necessary for specialized equipment, such as VHCs with integrated flow-check whistles or those designed for specific medications. Consulting with a pharmacist can clarify the availability and cost of a particular spacer model without a prescription.
How Spacers Improve Medication Delivery
The use of a spacer enhances medication delivery by overcoming two issues associated with using a metered-dose inhaler (MDI) alone: high velocity and poor coordination. When an MDI is actuated, the medicine is expelled at a high velocity, causing a large portion of the drug particles to deposit in the back of the throat and mouth. This phenomenon, known as oropharyngeal deposition, limits the amount of drug that reaches the lower airways.
The spacer acts as a deceleration chamber, slowing down the aerosol cloud and allowing the volatile propellant to evaporate. This process results in a finer, slower-moving mist of medication particles, ensuring that a greater fraction of the drug is respirable. By holding the medication in this chamber, the spacer provides a momentary pause, eliminating the need for the patient to perfectly synchronize the inhaler’s actuation with their inhalation.
This controlled environment allows the patient to breathe in the medicine slowly and deeply over several breaths, maximizing the amount of drug that penetrates the lungs. Reduced deposition in the throat and mouth is also important when using inhaled corticosteroids, as it lowers the risk of local side effects like oral thrush or hoarseness. Studies have indicated that using a valved holding chamber can increase the amount of medication reaching the lungs by two to four times compared to using an MDI alone.
Choosing the Correct Type and Size
Selecting the appropriate spacer involves distinguishing between the two primary types and ensuring the device is correctly sized. A simple tube spacer is an open extension that aids in slowing the medication, but a valved holding chamber (VHC) is preferred because it incorporates a one-way valve. This valve traps the aerosolized medication inside the chamber until the patient inhales, allowing for multiple breaths to capture the full dose.
Correct sizing is especially important for infants, young children, and patients who cannot form a tight seal around a mouthpiece. For these individuals, the VHC must be fitted with a tightly sealed face mask to prevent medication loss. The mask size must be appropriate, covering both the nose and mouth without excessive gaps, to ensure efficient drug delivery.
Older children and adults with adequate coordination can use a mouthpiece attachment, which typically offers more efficient delivery than a mask. Compatibility with the specific metered-dose inhaler (MDI) is paramount, as the MDI must fit snugly into the spacer’s port without leakage. Some spacers are universally adaptable, while others are manufactured for a single brand of inhaler.
Essential Maintenance for Hygiene
Regular cleaning is necessary for maintaining the hygiene and functional integrity of an inhaler spacer. Drug residue and moisture accumulation can encourage the growth of bacteria inside the device. Furthermore, the plastic material can develop an electrostatic charge, causing medication particles to stick to the chamber walls and reducing the available drug.
To clean the device, the spacer should be disassembled and soaked once a week in warm water mixed with mild dishwashing detergent. Soaking for about 15 minutes helps neutralize the plastic’s static charge and loosen residue. After soaking, the parts should be rinsed briefly in clean water, though some manufacturers suggest not rinsing to leave a slight detergent film that reduces static buildup.
The most important step is to allow all components to air-dry completely in a vertical position without wiping. Wiping the inside of the chamber can reintroduce a static charge or leave lint, which compromises the next dose. The spacer should be replaced every six to twelve months, or sooner if the plastic is cracked, worn, or if the one-way valve malfunctions.