editor’s report Connected Medical Revolution
Digital Medical Devices Fueling a Quiet Revolution in Health Care Digital electronic medical instruments are proliferating widely and rapidly throughout the medical community. Take a look at the supplemental publication coming out with this issue of RTC that will cover this phenomenon— Medical Electronic Device Solutions. by Tom Williams, Editor-in-Chief
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AUGUST 2010 RTC MAGAZINE
of certain elements of medical expertise into the devices. When such devices make their measurements they produce data, which can partially be acted upon by the
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ith all the attention that health care has gotten in the media in recent months, there appears to be a development that has largely escaped widespread notice. That is the migration of medical expertise into intelligent devices that are targeted not to replace trained physicians but to help spread their knowledge and services to a wider number of patients at specific levels of care. It probably comes as no surprise that medical devices and equipment are going digital, from thermometers to stethoscopes to glucosometers to sophisticated MRI and medical imaging equipment; all have incorporated appropriate levels of digital capabilities. Take something as simple as a stethoscope. One model advertises up to 24 db amplification with noise filtering and three frequency modes: cardiac, diaphragm (for lung sounds) and an extended range of 15 to 1000 Hz. But the digitization and enhancement of the basic device functions is only part of the story. When we get beyond simple functionality such as that of a thermometer or a stethoscope, we start to see the embedding
device itself such as flashing an LED if a blood sugar reading is out of range and/or connecting to the wider medical network for further analysis by qualified medical personnel. This opens up vast possibilities. Those possibilities involve the expansion of quality medical care to many more patients per doctor than is currently possible. Steve Kennelly, Senior Manager of Microchip’s Medical Products Group, notes that, especially in handheld and portable medical devices, 8- and 16-bit microcontrollers play some very significant roles in making patient information available to the medical practitioner as well as to higher level devices and software that can perform additional analysis and make significant data available to the physician as a formatted presentation for more efficient analysis. For example, an electrocardiograph (ECG) once consisted of a cluster of probes that were attached to the patient and then to channels on the ECG machine where they drove a set of pens that swept back and forth across the paper strip. The tests were administered by a medical technician and the results analyzed by the physician. The results (meaning the paper strip) were then stored in the patient’s record folder along with the doctor’s notes.
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An electrocardiogram (ECG) measures the electrical activity of the heart. The resulting waveform can be directly displayed, recorded or analyzed in real time. Courtesy Microchip Technology.