Currently there are different types of tests to study the behavior of the heart and monitor it. These tests are extremely important, because let us know in time if the heart is failing or has a problem. And because of that, today we submit to treatment or surgery to correct them when they are still small and manageable, before our life is at risk. The electrocardiogram, ECG or EKG, is one of those tests.
The electrocardiogram (ECG / EKG) is the graph obtained with the electrocardiograph to measure the heart's electrical activity as a continuous graphic tape. It also helps to know the duration of the cardiac cycle. It is the main instrument for cardiac electrophysiology and has a significant role in screening and diagnosis of cardiovascular diseases, metabolic disorders and predisposition to sudden cardiac death (Daja, Reljin, Reljin, 2001). The ECG has the advantage of being a medical procedure with results available immediately, which is noninvasive and is inexpensive.
Uses of ECG in Healthcare and Nursing
The ECG has a wide range of uses: (Alwan et al., 2006)
• Determine if the heart is functioning normally or suffering from abnormalities (eg. Extra beats or breaks - heart arrhythmia).
• Indicate coronary arterial blockages (during or after a heart attack).
• It can be used to detect electrolyte abnormalities of potassium, sodium, calcium, magnesium or others.
• Show the physical condition of a patient during a stress test.
• Provide information on the physical conditions of the heart (eg: Left ventricular hypertrophy)
ECG is required to be done in the following conditions: (Madias, 2008)
• The irregular heartbeat (arrhythmia)
• There are problems with the blood supply and oxygen to the heart (ischemia or infarction) or if there was a heart attack in the past. Sometimes they may have been mild and have happened without us noticing.
• Have congenital heart defects.
• The heart is inflamed (myocarditis).
• One of the chambers of heart of the patient is enlarged or thickened.
• There is a risk to suffer a heart attack in the future.
ECG Technology in Healthcare and Nursing: Past, Present and Future
A healthcare delivery system, with precision measurements becomes a more reliable diagnostic tool for an effective treatment of a disease. From a clinical point-of-view, the disease diagnosis is characterized by proper observations and accurate measurements of concerned parameters. Thus, proper evaluation of a signal, in the present context ECG signal, helps clinicians in quick treatment decision for better healthcare and nursing. The real time biomedical signal acquisition with online time interval measurements has always been in demand and is required to be taken up on priority for an early diagnosis in an automatic manner, mainly in case of elderly patients monitoring, living in remote areas (Madias, 2008). A number of researchers and academicians have put their viewpoints on the need of automation, of ECG parameters over the manual detection. New technological developments and the use of information technology to support the delivery of quality healthcare offer promising prospective towards the precise parameter measurements and ultimately online diagnostic success.
The system automation which connects the patient to the doctor or the nurse remotely, on the detection of emergency condition plays a vital role in providing immediate diagnosis and medication on time. The scheme of obtaining critical biomedical indicators using sensors on the body, signal conditioning and processing these signals before they are transmitted to the doctor or nurse live to obtain medical expert advice instantly, has a lot of uses in treating majority of the patients especially the elderly.
ECG: The Past
The first work regarding ECG recording which used the string galvanometer was published in 1906 by Einthoven. At that time, the focus was just on identifying if the patient had normal or abnormal readings. Initially there was a scarcity of resources in the hospitals due to which Einthoven conducted an experiment, in which he connected the patient with the telephone wire that transferred the signals from the patient to the galvanometer string which is the part of ECG device which was present in the laboratory. Then he compared the results obtained through telephone wires and the one obtained through ECG directly (without using telephone wires). He found that the results were the same which meant that telecardiology was successful. With the passage of time, the technology has advanced but the basic idea of using ECG is the same. Telephone lines were used to transmit signals from a distant locality to the hospital where the ECG machine was placed (Madias, 2008). This advancement was very useful in the healthcare and nursing. In the past, the techniques used to transfer ECG were based on analog signaling, frequency modulation and frequency division multiplexing. The next step in the advancement of ECG was taken by Rahm et al., since they used telephone lines along with acoustic frequency modulation equipment. In the year 1953, PSTN was put into use and no other equipment was required.
ECG: The Present
Indeed, the society is on the gateway of a new age and technology is poised to give a new sense of freedom by integrating the developments in computer networking, Internet services and medical technology. The transmission of biomedical parameters, most commonly ECG transformation of information on cellular phones in serious situations has turned out to be very useful lately but with certain limitations. The limitations in this kind of transmission of information are that the information transferred is not real time and the space for storing data is also limited (Madias, 2008).
Analogue techniques used over PSTN for transfer of ECG are commonly used nowadays but the signals transferred are not of high quality because of the interference of other frequencies and distortion of data. Moreover, the problem with this kind of data transferring is the limitation of bandwidth which between 300-340 Hz and the fact that signals cannot go down to 0 Hz. Now this kind of data transfer is not very useful when accurate data is required (Singh, 2008). In order to deal with these issues, the transmission of ECG is now done digitally, and it serves the following advantages over the previously used analogue method:
Low acquisition cost -- using digital technology, is a lot economical as compared to composite analogue circuit.
Data integrity -- the data is more reliable and accurate because extra noises and interferences are reduced.
Usage -- Time Division Multiplexing (TDM) offers more bandwidth as compared to frequency division multiplexing.
Compatibility and synchronization -- different signals can be transmitted in the same arrangement.
At present, advancement in technology has helped in developing a versatile, cost effective and application oriented web based analytical, informative and corrective action taking tool employing systems and devices like Internet, PC's and specially developed Graphical User Interfaces (GUI's) and thus has made advancement in ECG technology.
ECG: The Future
Advancement in technology has made medical equipment and devices more portable and simple to use. New ECG devices are not big and heavy, instead they are small, lighter, and user friendly. This has further made things easy for healthcare and nursing. The new devices do not require putting cables and applying electrodes on the patient's chest, instead, in these advanced devices an inbuilt sealed metal is used which is placed on the patient's chest and ECG is recorded (Forkner-Dunn, 2003) The patient himself can do this at home if the device is available. This new kind of device has empowered the patient, and thus has increased healthcare efficiency. Because of the supporting infrastructure of today's telecommunication, telecardiology enables the patients to carry their own medical devices and mobiles and when they feel that they have some irregularity in the rhythm of their heart, they can check their…