NVQ workbooks

KNOWLEDGE EVIDENCE QUESTIONS

UNIT TC1 - RECORD AND EVALUATE AN ECG AT REST

1.

Describe the basic structure and function of the cardiovascular system ie: heart, vessels and circulations.


Heart

The heart and circulatory system

The function of the heart is to continuously supply the whole of the body with blood to function properly. Fresh blood brings oxygen and food to the tissues and carries away unwanted carbon dioxide and other waste products.

The blood circulates around your body through a closed system of blood vessels. The heart is the pump, which pumps it around. It has four chambers and a one-way valve system. Each contraction, or heart beat, pumps blood forward into the arteries. The arteries divide off into smaller and smaller branches to supply a microscopic network of capillaries, distributing the blood to every part of your body.

Blood is collected from the capillaries by the veins. The branches of the veins join to form larger veins delivering blood back to your heart. Blood from your veins fills the heart as it relaxes during the interval between each contraction.

This total circulatory system is called the cardiovascular system. It contains about eight pints of blood, which your heart is continuously re-circulating. Each day, your heart beats about 100,000 times and pumps about 5,000 gallons of blood.

The heart is in fact two separate pumps, which work together. The right side of the heart receives dark, deoxygenated blood, which has circulated around your body. It pumps this to your lungs, where it picks up a fresh supply of oxygen and becomes bright red again.

The left heart receives fresh blood from the lungs and pumps it into the arteries, which supply the rest of the body. Each side of the heart has a thin-walled ‘collecting reservoir’ (the atrium) which helps to fill the thick-walled major pump (the ventricle). The heart wall is made of a special sort of muscle called the myocardium.

Like every other living tissue, the myocardium itself needs to be continuously supplied with fresh blood. This supply of blood comes from the coronary arteries.

2.

Draw a diagram of the conducting system of the heat.
Briefly describe the normal conduction pathway of the heart.

The bundle of His emits an electrical discharge which is picked up by the syno-atrial node. This then



3.

The normal heart produces a typical waveform.
(a) What is this normal rhythm called?

Sinus rhythm - as it originates from the sino-atrial node

(b) Draw a diagram of this waveform.




(c) Briefly describe its five components.



P = Atrial polarisation

Q R S = ventricular polarisation

T = ventricular re-polarisation

4.

How would you know if this conducting system was damaged by disease?

There will be alteration from previous ECGs
There are deviations from normal waveforms
T waves could be inverted

5.

Briefly describe some common disturbances of heart-rhythm and their causes.

Atrial Fibrillation.
Where the atrial muscle is not working as one and all the cells contract disryhmically


6.

What do the electrodes of the ECG record?

the electrical output of the heart

7.

Very briefly, what is the significance of the grid on the ECG paper?


this provides a benchmark against which the waveform and rhythm may be measured


8.

Ventricular ectopic beats can occur in healthy people when they are associated with an excess of tea, coffee or alcohol - TRUE or FALSE.



True

9.

A patent's ECG tracing shows ventricular fibrillation – why should this give cause for concern?

This constitutes a cardiac arrest and no pulse will be present.
Cardiopulmonary resuscitation is indicted

10.

You observe the abnormal rhythm of ‘asystole’ – what does this signify?

there is not cardiac contraction what so ever. If it is caught soon enough this can be chemically reversed. How this cannot be reversed by defibrillation.

11.

What is the advantage of the 12 lead ECG?

It looks at the heart in 12 ways.

It is a non-invasive way of gaining quite an accurate picture of the heart.





12.

Draw a diagram showing where these 12 leads are placed on the body.







13.

How can we avoid an erroneous recording/reading?

Ask the client to stay very still
Try to keep the leads still
Try to eliminate all extraneous power sources that may interfere with the process.
Ensure that all mobile phones are switched off in the vicinity
Ensure correct placement of electrodes





14.

Why is it important to check the ECG equipment prior to use? Briefly list the specific types of electrocardiograph.

To see if it is functioning correctly as to reduce the risk of hardware error.

12 lead
12 lead right sided
12 lead taken on the back on left or right
24 hour tape
3 lead













15.

(a) How do you prepare a patient for an ECG?
(b)Is the preparation any different between a routine or emergency procedure for ECG?


a) wash and dry hands
explain procedure to obtain informed consent
lie the patient down with 2 pillows (any deviation from this should be recorded on the ECG after production
raise bed to height that suits worker.
apply stickers to appropriate parts of the body
turn on ECG machine and ensure correct operation.
Attach leads
take reading
throughout the procedure, reassure client, answering questions within support worker role or seeking assistance when questions/problems are outside role.


b)there is no difference in non-emergency and emergency protocols.





16.

(a) Identify some anxieties that a patient might express when informed that he/she will need an ECG. How would you deal with this?
(b) Consider a patient from a different cultural background.
What would you do if a patient refused to have an ECG, for whatever reason?


a)Will it hurt?
no there will be no pain (except for hirsute males when the stickers are removed from the chest area)

will i get an electric shock?
No, this is taking a reading of the electrical activity of the heart, not giving out an electric current

Is it alright?
As a healthcare support worker, I am not permitted to pass comment on ECGs as I do not have the knowledge base to read them, nor the accountability to stand by what is said. It is the role of the doctor to report on all ECGs.


b) In certain cultures, male workers are not permitted to touch or care for female clients.




17.

If the ECG printout was poorly printed, what adjustments would you consider to rectify this?


check all the electrodes are connected properly
check to see that there are no extraneous electrical currents in the vicinity, ie mobile phones, electric mattress motors.
ask the patient to remain as still as possible.
relocate limb leads, if necessary, when they are in a stable position where their movement is minimized








18.

You’ve just taken the ECG and identified some abnormality. What do you do next?

As with all ECGs, they should be presented to a doctor. This must be done with the utmost expedition as it is very important as cardiac damage may be occurring or, in the worse case scenario, death could occur if nothing is done.









19.

What is the effect of Digoxin on the ECG?

This would show the complexes being further apart as digoxin has a slowing effect on the heart.






20.

What should be done before the ECG recording is filed away?
It must be signed by a doctor
It must have the following information on it:-
date
time
patient
existence of pain at time of ECG
whether the filter was on or not.






21.

How would you care for the ECG machine one you have finished using it?








22.

How and why does an ECG recording differ in a child?