ECG Practical summary

Question 1

What are the indications that someone needs an ECG?

Answer 1

-chest pain (biggest cause)
-acute myocardial infarction (heart attack)
-pulmonary embolism (clot in lungs)
-dizziness/ syncope
-arrhythmias
-drug efficacy
-pre-op

Question 2

What do we need to tell the patient before performing ECG?

Answer 2

Explain why we are doing it, help them to relax and collect details from them to ensure we have the correct person.

Question 3

What is the definition of an ECG?

Answer 3

This represents electrical events in the heart recorded on the surface of the body.

Question 4

What do we need to do regarding skin prep?

Answer 4

Make sure skin is clean and dry, abrade (take top layer of dead skin off), no oils on skin otherwise the electrodes will fall off.

Question 5

Which settings are operator dependent?

Answer 5

-Paper speed
-Calibration
-Frequency response.

Question 6

What is the standard paper speed?

Answer 6

25mm/s

Question 7

What is the standard calibration?

Answer 7

Sensitivity= 10mm/mV.
Standard measures 1mV over 10mm.
Has to be a calibration mark on the ECG.

Question 8

What is the standard frequency response?

Answer 8

0.05-150Hz

Question 9

Which leads are bipolar?

Answer 9

Leads I,II and III

Question 10

Which leads are unipolar?

Answer 10

Leads aVR, aVL and aVF

Question 11

What do bipolar leads measure?

Answer 11

They record from 2 sites and are amplifying the difference between the 2 sites.

Question 12

What do unipolar leads measure?

Answer 12

These record the true potential with respect to 0.

Question 13

Why is neutral lead put on right leg?

Answer 13

The neutral lead removes artefact.

Question 14

Process for where to put chest leads?

Answer 14

-V1- 4th intercostal RSE (right sternal edge)
-V2- 4th intercostal LSE
-V3- Midway between V2 and V4
-V4- 5th intercostal mid- clavicular
-V5- left anterior axilla at level of V4
-V6- Mid axilla at level of V4

Question 15

How do you find V1?

Answer 15

Find the angle of Louis. This is a ridge where the menubrum and sternum are fused.

Question 16

What colour is V1?

Answer 16

Red

Question 17

What colour is V2?

Answer 17

Yellow

Question 18

What colour is V3?

Answer 18

Green

Question 19

What colour is V4?

Answer 19

Brown

Question 20

What colour is V5?

Answer 20

Black

Question 21

What colour is V6?

Answer 21

Purple

Question 22

What is the anatomical view of limb leads?

Answer 22

These look at the heart in a frontal plane.

Question 23

What is the anatomical view of the chest leads?

Answer 23

These look at the heart in a horizontal plane.

Question 24

Which leads are inferior?

Answer 24

Leads II, III and aVF all are looking up at the heart.

Question 25

What causes a peak in an ECG?

Answer 25

When moving towards positive- pen moves up.

Question 26

What causes a drop in an ECG?

Answer 26

When moving away from positive- pen moves down.

Question 27

What are features of artefact?

Answer 27

-Baseline wander
-Muscle tremor
-AC interference
-Comments

Question 28

What causes baseline wander?

Answer 28

Poor contact with electrodes or chronic obstructive airway disease.