An interesting article titled “Wireless Medical Device Coexistence” (found here) was passed my way recently. The article made a case that by creating a formalized testing strategy the risks associated with the coexistence of wireless technologies could be reduced resulting in a safe and effective wireless medical device. After reading it – I began to consider the problems we all face with wireless device coexistence and began to ask myself if such testing would improve the coexistence challenge.
Many medical devices today include wireless interfaces that utilize 802.11, Bluetooth or even ZigBee all within the ISM (Industrial, Scientific and Medical) band. The criticality of such connectivity varies widely across the various medical device types that exist. The most critical of these devices require continuous wireless connectivity with a “zero or near zero” packet loss factor.
The paper points out that the IEC-60601-1-2 is the standard used for EMC (Electromagnetic Compatibility) testing of medical devices, but the standard does not include testing recommendations to determine the conditions necessary to maintain a wireless connection when subject to interference. Now some of you Biomedical and Clinical Engineers might point to the ISO-14971:2007 standard, but this is focused on identifying the risks during the product lifecycle and does not specifically address the RF aspects.
So I wonder, if the industry created a testing standard for medical device coexistence (in the ISM band), would this advance our cause and allow more of us to get a better night sleep? The article provides some examples of a suggested testing strategy (you can read it here), and I won’t debate the finer points but have to ask if this would result in a safer and more effective medical device. Read More »
Tags: Convercence, healthcare, IEC-60601, IEC-80001, ISO-14971, MDDS, Medical Device, wireless
I often engage in discussions with IT Directors, CIO’s, BioMed and CE teams at healthcare organizations worldwide. When the topic of medical device connectivity arises, it’s the point in the conversation where it gets – ah interesting. Points of view between the IT and Biomedical sides of the house are – sometimes aligned, but often there are gaps in the expected roles and responsibilities.
So rewind the clock a bit… back to the early 90’s when IBM had a foothold on its proprietary protocol known (and loved) as Systems Network Architecture commonly known as SNA. The two sides of the house back then were the mainframe group and the PC networking teams that were quickly emerging. The thought of providing end user connectivity to the big iron over something called Thinnet was very controversial in many big blue shops. I often thought that perhaps Thinnet was suffering from a market naming perception problem – but none the less at the time it was thought of as an inadequate transport technology to provide green screen access to the datacenter Big Iron (Yes — I said Green Screen). The general feeling was that the sky fall, on-call pagers would endlessly go off and the availability and performance reports would inevitably point the fingers of blame to the mainframe – something that was simply not allowed to happen!
Forwarding the clock a bit – say mid to late 90’s – the next and potentially the most important wave to date of convergence arrived – Voice. The thought of putting voice traffic on an IP network was believed by many at the time as just crazy. Again, falling skys and lots of dropped and unintelligible calls would result – the networks HAD to be separate. It was the way it was… but slowly over time, voice along with its cousin IBM SNA (both sharing the same sir name of “critical” btw) were riding the same converged network and living happily together. Read More »
Tags: AAMI, BioMed Network, convergence, IEC-80001, The Joint Commission