Anyone knows how MedGem works ?

[El Greco]

MedGem is a device which measures oxygen consumption in order to determine the (RMR) Resting Metabolic Rate. MedGem-100 is rather pricey ($1900) and it is only good for 100 measurements. After that you have to re-order the device.

Well, we've got one of these and we've been wondering how the hell does it work and why exactly isn't it any good after 100 measurements ?

 

[Oleron]

My guess is that it simply measures the volume of air inhaled/exhaled to measure metabolic rate. As such it probably gets filled with germs and dribble. The 100 uses thing might just be a hygiene thing.

 

[El Greco]

The thing comes with one disposable mask for each measurement, so I don't think this is the issue. Besides, it looks ridiculous to pay for the whole mechanism again if it is just a matter of hygiene.

 

[Oleron]

Perhaps it is more sophisticated than I thought. Maybe it uses a substrate to chemically bind the CO2 or the O2 and analyses the result. Similar to a police breathalyser.

I used similar technology when I was employed by an environmental monitoring company. We were monitoring for a wide range of airborne chemicals and would use a pump to suck a given volume of air through an absorbent material (omnisorb). We then removed the cartridge of omnisorb for GCMS analysis. Obviously each new measurement needed a new cartridge- possibly this is the source of the 100 uses limitation.

 

[El Greco]

Well, it'd better be sophisticated, and it'd better be using a filthy expensive substrate, because I wouldn't be all that happy to find out that what renders this 1900-dollars-thingie useless is the depletion of some dirty cheap chemical.

 

[Rolfe]

I've had a look, but they're not being very forthcoming about the technology. It's not a measurement I'm very familiar with because it's a point-of-care system (and I'm in the lab), and things have obviously moved on a lot since I did my PhD in exercise physiology over 20 years ago.

I think it's on the level, though. I think there are reagents in there that are being consumed, hence you can buy one which has 30 tests "pre-loaded", or 100 tests, to suit your workload.

Rolfe.

 

[Zombified]

Sounds like the logical conclusion of the ink jet cartridge business plan. In a lot of cases, what looks like the expensive hardware is actually sold at a loss and the manufacturer makes money on the refills. This is true for printer vs. cartridges, cellphones vs. airtime, XBoxes vs. game disks, razors vs. blades, all sorts of stuff.

It may be that the possibility of contamination means the device can't really be serviced in the field, so the simplest expedient is to simply send it home for refurbishing anyway. In which case the cost of the device reflects the service and labor cost rather than the materials cost, plus some fraction of the cost of the hardware and development based on how many reorders the manufacturer thinks he'll get.

Very, very few things are priced based on the cost of materials, and there is a word for them: "commodities"

 

[patnray]

Slightly off topic, but some years ago, while working as a Manufacturing Engineer, I purchased an HP Signal Generator. At the time we did not need the modulation feature, so we ordered it without it. Later we had a requirement for modulation, so I ordered the modulation "module". For around $300 I was expecting a card to plug into the device. What we received was a software code to turn on the modulation function!!!