#Heart monitor lead placement how to

The phase from the initial impulse from the SA node to the AV node depolarising is called the PR interval. At this point the wave is slowed down to allow the ventricles to fill.

The electrical impulse hits the fibrous septum and can not be transmitted through this but it will reach the atrio-ventricular node which will depolarise.

As a result of the atrial depolarisation the atria should contract forcing blood through to the ventricals.

A wave of depolarisation is conducted through the atrial cardiac cells, this in turn creates a deflection away from the base line know as the P wave.

The initial electrical impulse (depolarisation) usually begins here.

The Sino-atrial node is also called the pacemaker.

Something to bear in mind in theory this line should be straight however when you are recording the ECG of a patient they have impulses through other muscles such as the intercostal muscles for breathing so this base line may move slightly up or down like a rolling wave.

As the cells depolarise and repolarise they cause deflections above and below this line. The will produce a line on the paper This is called the iso-electric line or base line. First we need to remember that if you monitored the myocardial cells that are polarised or in a ready state.This is because ABCD had been used before in correlations and N has a mathematical meaning and O is used for the origin of the Cartesian coordinates, P was simply the next letter. NB For your information not necessary the students: 1895 Einthoven names the 5 deflections seen as PQRST. That clinical assessment of the patients condition is imperative ie not breathing, no pulse don’t really need a 12 lead ECG but start BLS. PLEASE IMPRESS ON THE STUDENTS THAT WHAT IS PRODUCED ON A MONITOR OR 12 LEAD ECG IS NOT NECESSARY CARDIAC FUNCTION. What will be seen on a monitor or on a 12 lead ECG print out for a single cardiac cycle is this type of wave form.Some revision for you can you name each of the structures pointed out? Bundle of His is approx’ 10mm before bifurcating to form the left & right bundle branchs.After the electrical impulse has passed through the cell, the potassium re-entres the cells and the sodium leaves, causing repolarisation. While in this state the cardiac cells contract, they are unable to respond to any further impulses until the repolarise. The electrical spark is then conducted to the remaining cells causing depolarization. This movement causes a spark of electricity. When a pacemaker generates an electrical impulse to a polarized cell, most of the potassium moves to the outside the cell and most of the sodium moves to the inside of the cell. In this state the cells are said to be polarized or in a ready state. Normally potassium prefers to be on the inside of the cell while sodium prefers to be outside. (this is an important concept that the students understand) NB For your info or if students ask: All tissues, including cardiac muscles are made up of single cells that contain chemicals potassium and sodium. A 12 lead ECG is a print out of the electrical impulses in the heart NOT mechanical function. This is what can cause arrhythmias (abnormal rhythms). However myocardial muscle cells have an ability called automoticity (the ability to initiate a spontaneous impulse) from anywhere across the myocardium. Essentially the heart is a muscle that has some properties which other muscles do not have, all muscles will transmit an impulse that as a result will make the muscle contract. What is the heart? A pump, A muscle which pumps blood.

#Heart monitor lead placement how to

Introduce the session with and explanation that we will split it up into 3 sections: Presentation of what is an ECG Demonstration of how to take an ECG Basic ECG interpretation and normal values It may be an idea to ask the group if they have ever seen an ECG done or had and ECG.Now a demonstration of taking an ECG from a Represented by deflections away from this line. The electrical events of the cardiac cycle will be This represents the resting potential of the heart.  To be able to perform a basic ECG interpretation. To introduce to the student the principlesĪnd its relationship to the cardiac cycleġ2 Lead Machine that gives a 3D perspective.