Some semi recent news on Medical Body Area Networks (MBANs) from GE Research and the FCC. It starts with GE's September 1, 2009 press release (pdf), where they announced:
...an intiative aimed to develop wireless medical monitoring systems, or body sensor networks (BSN), which would replace the traditional tangle of bedside caables used to capture a patient's vital signs. GE's vision for the systems would enable wireless monitoring from anywhere in the hospital -- or even remotely at home.
For the past couple years, GE's been pushing for the allocation of spectrum for MBANs. The press release notes that, "The FCC recently issued a notice of proposed rulemaking (NPRM), acting upon GE Healthcare’s petition to establish a new, vendor-neutral dedicated radio frequency band for low-power, short-range, wireless patient monitoring devices. This petition requested creation of a new Medical Body Area Network Service (MBANS), to support wireless sensors that monitor a patient’s health state, linked together in body sensor networks."
Here's David Davenport talking about their wireless sensor initiative:
Apparently, GE's going after the cable replacement business for traditional multi parameter patient monitors. LifeSync has had a product replacing ECG cables (by far the most predominate type of cables in clinical use) for several years. LifeSync also controls the Besson patent (licensed to them exclusively by Motorola) that applies to wireless sensor based physiological monitoring.The FCC Notice of Proposed Rulemaking referenced is from June 29, 2009. Another "article" written by a law firm apparently engaged by GE was published March 20, 2009 and outlines:
Proposed Frequency Band: "identified the 2360-2400 MHz band as the preferred frequency band based on engineering studies showing that MBANS devices can successfully coexist with incumbent operators and users." I would love to see that coexistence data. In a conversation with David Davenport of GE Global Research that, he told me that spectrum just outside 2.4 GHz was desired because it would enable the use of off the shelf 2.4 GHz components, with only minimal modifications.
Permitted Operations and Eligibility: "the proposed rules limit the type of devices that will be permitted to operate within the spectrum to those involved in the monitoring, diagnosing or treatment of a patient." No big deal here.
Authorized Locations: While only medical applications may use the spectrum, users "will be fully mobile, both inside and outside of healthcare facilities, without restriction." This means purpose built MBANs just for health care. Imagine how long it took the networking industry to get Wi-Fi to be plug and play, fast and reliable (when deployed properly). Imagine all the money that those vendors spent getting their industry to this point. Now imagine what a half dozen medical device vendors can spend repurposing a bunch of Wi-Fi technology for MBANs. Think, "economy of scale" -- there won't be any.
Spectrum Sharing Requirements: Here's the big issue -- "The proposed rules do not require the use of any specific standard protocol but GEHC anticipates that industry standardization efforts may occur. Currently, the proposed rules only require that all devices implement basic contention-based mechanisms to allow predictable and fair access to the spectrum." The same vague promises of working out an industry standard after the fact were made when WMTS was created. Nothing ever came of that, and there were very serious coexistence problems with both GE's and Philip's WMTS the first several years they were on the market. This is another recipe for the creation of vendor specific proprietary systems, or at the very least erecting barriers to entry and higher switching costs. This is a great product strategy for GE (and Philips), but not so good for smaller competitors with not so large R&D budgets.
Emission Limits: This is low powered stuff, "MBANS devices be permitted to have fundamental emissions of up to 0 dBm EIRP for the proposed maximum 1 MHz emission bandwidth."
Again, like WMTS, it appears that nothing will preclude medical device manufacturers from using other portions of the ISM band do develop and sell their own wireless sensor based systems (again, like Continua and others).
Here's a great summary from mobihealthnews, written by Mintz Levin (another law firm engaged by GE?). More details are provided on the potential frequency allocations (a total of 3 bands), and specific issues the FCC is looking for comments on. Conspicuously absent are any instructions on how to submit your comments (except through Mintz Levin).
Here's a pdf of the FCC's press release on the proposed rule, and a pdf of the actual Notice of Proposed Rulemaking. More later.
Here's a photo of LifeSync's Wireless ECG rig. Note that each sensor (there can be as many as 12 of them) is not wireless.
Tim - great picture of the wireless electrodes 🙂
Seriously, this paragraph in Mr Levin’s article made me groan:
“2400-2483.5 MHz Band
This band is used by Industrial, Scientific and Medical (ISM) equipment on a non-licensed basis under the FCCâ€™s rules. In addition to ISM devices, a portion of the band is allocated to amateur radio operators, the federal radiolocation service and unlicensed equipment such as Wi-Fi routers and cordless phones. The FCC seeks comment on whether MBANs could operate in this band under current rules or whether new rules would be required to regulate MBANs using this band.”
I know for a fact healthcare organizations are already having issues with wireless allocation and ‘dead spots.’ Whoever has the frequency manager job will love this addition as the risk of a dropped physiological signal have a higher risk than a dropped signal on a COW. Additionally, what is the range? Can the patients truly ambulate (i.e. in the hallway, down to x-ray, etc)? Or would that be a function of the design by the manufacturer? Many hospitals use third-party electrodes - will this MBAN be truly worth the extra cost? Frankly, only if the patient could truly ambulate as described above without loss of the physiological signal would this possibly be worth any extra cost.
Again, thanks for posting this article and highlighting the possible motives.
Great Summary. BANS have been discussed in Hospital applications for some time, and I have yet to see a convincing use case justification.
While they reduce cable flex issues they introduce a huge range of additional complexity to the workflow - battery management, pairing and authentication etc.
If there is a clear use case for BAN transmission of simple 3 lead ECG then I would suggest the adoption of some industry standards for use in the new band.
PHY/MAC - Use the Bluetooth Low Energy standard
Data Layer - Use IEEE 11073
By mandating these open standards in the spectrum allocation with their associated interop and certification methods we stand a much better chance of a multi vendor ecosystem
Tim - an update on this story:
It seems that GE is facing resitance to the use of this highly valuable spectrum.
An interesting view on spectrum allocation for medical provided by Fraser Edwards of Cambridge Consultants:
Essentially it can be a huge waste of valuable spectrum if it can only be used by a few device vendors in a hospital setting. Fraser is advocating new technical methods to make better use of spectrum. These should enable safe and reliable Hospital systems as well as efficient spectrum use.