Design challenges and decisions – the mouthpiece

Commercial disposable mouthpieces > $1 each

One of the most fun and challenging parts of this project is trying to build creative solutions to problems that are inefficiently solved today by commercial markets – in other words, solutions rooted in a different ethic that presume an abundance of funds.

In the case of the spirometer, nowhere is this more apparent than with the mouthpieces that commercial spirometer companies manufacture to accompany their machines. The majority, if not all, manufacturers sell disposable mouthpieces to minimize the potential of nosocomial contamination. With good reason. We know from studies of SARS, for example, that respiratory equipment can be a vehicle for infection. And some respiratory physicians, like my friend Raj Singh, a chest physician at Apollo Hospital in Chennai and GINA Executive Committee member, have argued that we don’t know enough about how devices used in respiratory practice – spirometers, peak flow meters – might spread disease.

The disposable mouthpiece is obviously a smart way to tackle that, but in many cases companies charge more than a dollar per mouthpiece. 

Yesterday our group spent a while sharing ideas about what kind of mouthpiece we should aim for – disposable or reusable – and ways to get us quickly to a workable solution.

Initially, a reusable mouthpiece that could be easily decontaminated seemed like a good option; after all, you don’t have to invest in manufacturing and distributing mouthpieces. We moved on to thinking about how you would disinfect a reusable mouthpiece and what kind of design would guarantee that cleaning is done (and done thoroughly) after use.

We quickly realized that just as a disposable solution presumes an affordable and available supply of mouthpieces, so does a reusable mouthpiece require a supply of disinfectant material, and of course, the intention to disinfect. We know that in many cases, clinicians in low and lower-middle income settings reuse equipment designed to be disposed of, and that, no matter how misguided, there are lots of practical reasons for this (see Mark Nichter and M. Lakshman’s article for a great ethnographic look at the behavior of providers in India around the reuse of  injection paraphernalia).

So yesterday we came up with two main directions, each with a couple of variations, that we could go:

Develop a permanent mouthpiece:

• And a cheap and easy way to disinfect it, or
• A simple and widely available disposable barrier (balloon, condom, plastic bag)

OR

Develop a disposable mouthpiece, that: 

• Can be made from locally available materials (soda bottles, toilet paper rolls) 
• Could be manufactured by local people as a cottage industry
• Deteriorates after use to limit repeat usage

In the end, we opted to go forward with the latter option: Try to develop a very cheap disposable sleeve, made from a material with a limited lifespan. We also decided to try to alert providers and patients to the importance of ensuring that a new sleeve was used by each patient by adding this point to the audiovisual materials we’re developing to guide patients and physicians through the test.

Today we start looking into the cost and type of materials that might work. We’d love feedback on the decision or suggestions about materials we should investigate.