Portable Microcomputer-Based Instruments
One example of a portable device is the portable arrhythmia monitor which monitors a patient's electrocardiogram from chest electrodes and analyzers it in real time to determine if there are any heart rhythm abnormalities. We designed a prototype of such a device more than a decade ago. Because of the technology available of the time, this device was primitive compared with modern commercially portable arrhythmia monitors. The evolution of the technology also permits us to think of even more extensions that we can make. Instead of just assigning a heart monitoring device to follow a patient after discharge from the hospital, we can now think of designing a device that would help diagnose the heart abnormality when the patient arrives in the emergency room. With a careful design, the same device might go with the patient to monitor the cardiac problem during surgery in the operating room, continuously learning the unique characteristics of the patient's heart rhythms. The device could follow the patient's throughout the hospital stay, alerting the hospital staff to possible problems in the intensive care unit, in the regular hospital room, and even in the hallways as the patient walks to the cafeteria. The device could them accompany the patient home, providing continuous monitoring that is not now practical to do, during the critical times following open heart surgery.
There are many other examples of portable biomedical instruments in the marketplace and in the research lab. One other microcomputers-based device that we contributed to developing is a calculator size product called the CALTRAC that uses a miniature accelerometer to monitor the motion of the body. It then converts this activity measurement to the equivalent number of calories and display the cumulative result on an LCD display.
PC-Based Medical instruments The economy of mass production has led to the use of the desktop PC as the central computer for many types of biomedical application. Many companies use PCs for such application as sampling and analysing physiological signals, maintaining equipment databases in the clinical engineering department of hospitals, and simulation and modeling of physiological system
The electrocardiogram (ECG) is a graphicalrepresentation of the electrical activity of the heart and isobtained by connecting specially designed electrodes to thesurface of the body . It has been in use as a diagnostic toolfor over a century and is extremely helpful in identifyingcardiac disorders non-invasively. The detection of cardiacdiseases using ECG has benefited from the advent of thecomputer and algorithms for machine identification of thesecardiac disorders.
A new dimension byintroducing the concept of vectors to represent the ECGvoltages. He is also the first individual to standardize theelectrode locations for collecting ECG signals as right arm(RA), left arm (LA) and left leg (LL), and these locations areknown after him as the standard leads of Einthoven or limbleads