![pics of a cardiograph pics of a cardiograph](https://thumbs.dreamstime.com/b/cardiograph-4503828.jpg)
Using the galvanometer (EKG machine), differences between electrical potentials at different sites of the body can be recorded. The activity of the heart produces electrical potentials that can be measured on the surface of the skin. The wave of depolarization moves across the atria, through the AV node, into the Bundle of HIS, down the Bundle Branches, and finally through the Purkinje fibers which conduct the electrical impulses throughout the ventricles. Remember that the normal conduction of the heart begins in the SA node. The frontal plane axis is the orientation of the heart’s electrical activity in the frontal plane. It is also important to understand that 12 different leads pick up those impulses as they travel in many different directions through the heart.
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The direction in which the impulses flow in the heart is important. In order to accurately interpret the 12-lead EKG, you must have an understanding of the electrical activity of the heart. Every time you see a blip mark, the next lead is being recorded on the tracing. These marks are for the purpose of showing the leads as they are changed. “Blip Marks” are pointed out on the tracing. The 12-lead EKG tracing below was obtained with universal lead placement. As mentioned earlier, the electrodes will be sensing the electrical impulses from the heart muscle at ht various locations and with various voltages, either positive or negative. This is usually accomplished by attaching the leads, according to instructions, on each wrist and each ankle. As the name implies, the limb leads are attached to the four limbs.
#PICS OF A CARDIOGRAPH HOW TO#
Once you know how to operate the machine at your facility the next concept to understand is the placement of the leads.
#PICS OF A CARDIOGRAPH MANUAL#
Be sure to read the entire instruction manual for the machine including: how to start the machine, how to load the paper, how to calibrate the machine (if needed), and any other pertinent information needed to safely and accurately run the machine. Be sure to clean the electrodes before and after each use, as gel will tend to build up. In most cases, the metal electrodes will also need to be coated with conductive gel prior to attachment to the patient. In most instances, the patient electrodes will be attached with the use of either flat elastic straps or by cloth Velcro straps. The instructions for the machine will show you how to attach the leads to the patient. Be sure you are familiar with the machines at your facility. Then all you need is practice.Įach 12-lead EKG machine will have its own instructions for use. We will also demonstrate the basics of interpreting the results.
![pics of a cardiograph pics of a cardiograph](https://i.ytimg.com/vi/zntB6ZRauQA/maxresdefault.jpg)
We will demonstrate how and where to attach the leads in certain places. We will present the basic clinical aspects of the 12-lead. This course is meant to give the nurse a practical education concerning the 12-lead EKG. It is a normal tracing (shows normal sinus rhythm). A 12-lead ECG consists of three bipolar limb leads (I, II, and III), the unipolar limb leads (AVR, AVL, and AVF), and six unipolar chest leads, also called precordial or V leads, (, ,, ,, and ).īelow is a sample of a 12-lead EKG tracing. A lead composed of a single positive electrode and a reference point is a unipolar lead.įor a routine analysis of the heart’s electrical activity an ECG recorded from 12 separate leads is used. A lead composed of two electrodes of opposite polarity is called bipolar lead. However, neither the electrical activity that results from the generation and transmission of electrical impulse, nor the mechanical contractions or relaxations of the atria and ventricles appear in the electrocardiogram.Īn EKG lead consists of two surface electrodes of opposite polarity (one positive and one negative) or one positive surface electrode and a reference point. This electrical activity is readily detected by electrodes attached to the skin. The electrocardiogram is a graphic record of the direction and magnitude of the electrical activity generated by the depolarization and repolarization of the atria and ventricles of the heart. This section will give you a basic understanding of how to take a 12-lead EKG, how to place the leads, and how to begin to interpret the tracing. It will take much practice of you to be able to interpret a 12-lead ECG tracing. This section is meant only as an introduction to the 12-lead ECG. This allows an experienced interpreter to see the heart from many different angles. Each lead is meant to pick up electrical activity from a different position on the heart muscle. The 12-lead ECG gives a tracing from 12 different “electrical positions” of the heart. This chapter presents an introduction to the 12-lead ECG.