More electronics are being employed in medical devices to improve functionality and reduce healthcare costs. Standalone platforms like the Nipro Diagnostics SideKick disposable blood glucose testing system, which uses a Texas Instruments MSP430 microcontroller, are being complemented by connected devices in homes and hospitals (see “Disposable Solutions With Low-Cost MCUs” at electronicdesign.com).
The increased interest in the creation of more medical and healthcare devices is highlighted by new standards addressing this area. For example, the USB-IF Personal Health Working Group has created the USB Personal Healthcare Device Class v1.0 specification.
Likewise, wireless device standards can be found in the Bluetooth and ZigBee arenas. The Bluetooth SIG Medical Devices Working Group’s specification includes the Bluetooth Health Device Profile and Multi-Channel Adaptation Protocol v1.0. The ZigBee Alliance has defined the ZigBee Health Care Protocol.
These standards provide low-power, wireless communication for health monitoring devices. The challenge is to safely support thousands of devices in hospital environments and hundreds in home environments.
Recalls And Approvals
The U.S. Food And Drug Administration (FDA) is a key player when it comes to safety in medical treatment. It is tasked not only with food and medicine oversight in the U.S., but also devices. It approves devices and can also issue recalls when problems are detected.
Recently, the FDA recalled thousands of Baxter International Colleague single- and triple-channel volumetric infusion pumps (see the figure). Baxter is only one of many suppliers for this type of device, and there can be many problems related to the delivery of too much or too little fluid medication, in addition to missed or delayed treatments.
In many cases, the use of these devices is even more challenging because they may be utilized for patient controlled analgesia (PCA). Patients using insulin need to account for meals and exercise when determining what the pump should provide, so user interaction comes into play as well.
The discussion becomes even more complex when networked and wireless connections are added to the environment. Now security and interoperability become key parts of the safety equation.
Safety And Security
The Continua Health Alliance is an industry organization that addresses system interoperability in the personal connected health solution space. It has taken a broad look at the issues, all the way up to a multi-enterprise view. Guideline specifications have been created so certified products that will be interoperable can be delivered.
One challenge developers will need to tackle will be secure communications and identification. Secure micros will play a big part in providing interoperability with security and safety (see “Security Micros Combat Counterfeiting,” p. xx). For many developers, this will be as new as the related guidelines and necessary approvals needed for products in this market.
Designers looking to enter this marketplace will be able to take advantage of the new standards, yet they need to be aware of the significant effort involved in delivering safe and secure systems that can be approved for use. Established vendors have a significant advantage, but standards may provide a more integrated and diverse network of medical devices.
Continua Health Alliance