This article stems from a conversation we[Iltifat Husain, Felasfa Wodajo] had with Mike Foley, executive director of the Bluetooth SIG – a group that develops universal bluetooth standards
Bluetooth technology allows devices to communicate and transfer key information wirelessly. The recent released of the Bluetooth 4.0 standard contains many specifications that could seriously increase adoption of the standard among medical device manufacturers. For example, the new standard calls on bluetooth devices to maintain power for weeks to months without a charge.
Imagine walking into the MICU or NICU, or any other ICU unit, and not seeing mountains of wires connected to your patients. Rather, they have small bluetooth sensors attached to them, synced wirelessly to display monitors next to them.
Transporting patients to imaging rooms and other locations would be a breeze, you would cut down the risk of bacterial infections from the lengthy wires, and you wouldn’t have to worry about people tripping on wires. These are just a few of the potential benefits.
Background
The Bluetooth standard has been around since 1999 when first Ericsson and then, quickly, other manufacturers of mobile devices and cell phones came together to specify a standard for near-distance wireless connectivity.
The Main Features of Bluetooth:
– Operates in the 2.4GHz frequency band without a license for wireless communication.
– Real-time data transfer usually possible between 10-100 meters
– Close proximity not required as with infrared data (IrDA) communication devices as Bluetooth doesn’t suffer from interference from obstacles such as walls.
– Supports both point-to-point wireless connections between mobile phones and personal computers, as well as point-to-multipoint connections to anable ad hoc local wireless networks.
The standard has been very popular with just about every cell phone manufacturer supporting it in the majority of devices. Due to its low power usage and very cheap, bulk produced electronics, it has been incorporated in many types of devices, ranging from the ubiquitous wireless headsets for telephones to popular consumer fitness devices such as the Nike-iPod/iPhone sensor that measures distances run by joggers.
In 2006, the Bluetooth Special Interest Group (SIG), which is the consortium of industry supporters responsible for developing the standard, set to build a standard to incorporate use of medical devices. This was a natural fit for the specification since device to device communication is an everyday occurrence in hospitals and doctors’ offices – as mentioned above.
The specification is now complete with 30-40 vendors already qualified to support it and we’re hopeful they will bring useful products to market.
Integration – the “Health Device Profile”
Over 20 types of Bluetooth profiles already exist and have been adopted in varying degrees by manufacturers. These include the Advanced Audio Distribution Profile (A2DP) – allows use of stereo headphones to listen to music over Bluetooth, the Hands-Free Profile (HFP) – allows hands free dialing inside a car, and the File Transfer Profile (FTP) – allows transfer of files over Bluetooth.
The recently released Health Device Profile (HDP) is specifically tailored for medical applications by incorporating the available Institute of Electrical and Electronics Engineers (IEEE) specifications for medical device connections directly into the specification. What this means is manufacturers that already use IEEE standards for their medical devices (e.g. pulse-ox, glucose meters, etc), can transition their device connectivity easily onto the Bluetooth HDP.
Many device-specific IEEE specifications already exist for personal health devices, such as weight scales, thermometers, and glucometers. In fact, many manufacturers were already using Bluetooth wireless connectivity for such devices in the marketplace but use their own proprietary protocols for encapsulating the data. What the HDP allows is standardization of the data format, increasing interoperability and, hopefully, leading to a flourishing market of health related devices using wireless communication.
Bluetooth advantages
When asked why choose Bluetooth over other wireless communication standards, Dr. Foley responded cost and power consumption. While Wi-Fi connectivity is ubiquitous throughout hospitals and now most offices, the power needed to maintain a wi-fi connection precludes its use in tiny medical devices with minimal capacity for battery storage. More expensive devices, such as cell phones, can afford to maintain a cellular connection, such as 3G or EDGE, but this cost would prevent widespread adoption in small, potentially disposable medical devices, where the additional cost of wireless electronics has to be limited to a few dollars.
Manager devices
The vision of HDP is that a nearby manager device (“sink” in HDP terminology) would be responsible for aggregating and transmitting information collected from one or more Bluetooth devices. Thus, a device by the bedside could collect information from multiple patient sensors and transmit it over the hospital Wi-FI network to doctors and nurses.
Potentially exciting is the prospect that a nearby mobile device, such as a smartphone, would be the aggregating device. Thus, a continuous reading of, say, movement (i.e. exercise) or heart rhythm data, could be collected and forwarded to the cloud for review by the person or her physician. This is where the promise of HDP to affect the consumer medical space lies – an always connected, mobile interface into useful lifestyle and medical information that can help patients and physicians.
Plus, no more tripping over wires.
Iltifat Husain contributed to this article.