Cardiac Action Potentials: A Case Study

An electrocardiogram (ECG) records the electrical activity of the heart and is affected by the magnitude and direction of the current flow. It works by placing electrodes on the skin as the body is a good conductor of electricity. There are leads attached to an amplifier within the machine, which must be clipped to the edge of the electrodes. The ECG is recorded from 12 different electrode sites. The amplitude and the shape of the signals depend upon the position of the electrodes (Brown, 1999) (Conover, 1992).
The SA node produces the pacemaker potential and if this reaches the threshold then an action potential is generated. There are five stages involved during cardiac action potentials, during these stages there is a flow of ions through
These further tests help to make a diagnosis and can be used to find out more information than from a normal resting ECG (BCPA, 2014).
There are some safety issues concerning an ECG. The first issue is faulty equipment which can cause problems if the leads or cables are broke, this can cause an issue as it puts the patient in danger of accidental shock if the equipment is extremely worn as it can cause improper grounding (Lippincott Williams & Wilkin, 2008).
The standard ECG recording is paper speed must be 25mm/s and the calibration should be 10mm/mV. If these are changed there must be a notice on the ECG after printing out an original with the standard settings. In the standard recording the filters shouldn’t be turned on as it distorts the ECG, although in extreme circumstances it may be useful to reduce interference. The ECG produced must be clear and artefact free so it’s easy to interpret. The computerised interpretation shouldn’t always be followed as it is sometimes incorrect therefore the professional must be able to interpret it themselves (SCST,