Step-by-Step Guide to Recording a Standard ECG Accurately

[Music] [Music] good morning i am dr a ahmed basha

professor of physiology chettinad hospital and research institute today i will be speaking about

how to record a standard ecg that is recording of a standard ecg ecg

an important diagnostic tool in cardiac care modern ecg machines are portable and they are very much user

friendly but even though if it is an user friendly device

errors in recording an ecg may end up with wrong diagnosis

and also it will affect the management of cardiac diseases

so the greatest challenge in recording of an ecg is a consistent recording technique must be

adopted the personal whoever recording ecg needs to be

qualified trained and he or she has to be an expertise in

the recording technique so in this module we are going to see a

clear step-by-step approach in recording of an ecg in ecg ascii guide

we are going to see a step-by-step approach under following heading

number one is what are the prerequisites

in prerequisites ecg recording personal that is we are going to see

who can record the ecg and how to identify the patient

and how to maintain the privacy of the patient next is patient preparation

under precision preparation we are going to learn about how to get an informed consent

how to place the patient over the couch next how to prepare the skin for the placement of electrode we are going to

learn under electrode placement we are going to learn about

how to place the limb leads and where to place the limb leads as well as chest leads that is the techniques for

locating the chest leads next how to obtain a good quality ecg

recording in that we are going to see what is the paper speed to be kept while

recording how to calibrate the ecg machine and how to avoid the artifact

after recording ecg what are the steps to be done we are going to see one by one

first we are going to see ecg recording personal ecg recording has to be done only in the

health care setup the ecg recording personnel must be a qualified

trained and expertise in the recording techniques the personal may be

a doctor a nurse or an ecg technician

or a researcher especially those who are involving in the ecg related research activities

and allied health professional so these health care providers

can record ecg with the proper training and expertise in the recording techniques

next patient identity the healthcare provider must confirm the patient identity before recording the

ecg how to confirm the patient identity patient identity can be confirmed by checking opd or ipd number

next the healthcare provider has to check the name with initial because sometimes two person may be with

the same name hence always check the name with initial next healthcare provider has to check

for age of the patient six of the patient then wrist band especially for the pediatric population wrist band has

to be checked for the confirmation of the patient identity further

the health care provider can check for case record to confirm the patient identity

but in case if the patient is not able to speak or not in a good orientation the

healthcare provider can ask the caretaker of the patient to confirm the patient identity

patient privacy the healthcare provider must maintain the health information

privacy and also he or she has to adopt the human values

especially at the time of recording an ecg the ecg recording to be done in a closed room

if the patient is a female patient one of the female what staff member or a patient attender must be present

throughout the ecg recording procedure next is

informed consent the health care provider must inform the patient about the procedure

of ecg recording in a friendly language that is the healthcare provider has to say to

the patient that ecg is a record of an electrical activity and the procedure involves placing of an

electrode over the body sites and that electrode is connected to the ecg machine the ecg machine records the

ecg so entire procedure has to be explained to the patient

and gain a consent from the patient to proceed the ecg recording next we are going to see

patient position under patient position exposure of

lower limb and wrist is necessary to connect limb leads adequately expose the patient chest

for placement of precordial electrodes offer a blanket to the patient so that

patient has to cover the entire precaudal area only at the time of recording

the for placement of electrode that particular area alone has to be exposed the patient has to lie down on a

clinical examination couch with the head tilted at an angle of 45 degree ask the patient whether the patient is

feeling any discomfort or any breathlessness pain etc only if the patient is

comfortable then you proceed for ecg recording next we are going to see skin

preparation skin preparation is done in order to avoid an artifact in ecg

some people may have additional hair in their body that additional hair may

interfere ecg recording in order to avoid that wherever you are going to place the

electrode that particular area alone has to be cleaned under particular area here that

is the hair where it is present in that particular area has to be shaved

in case if the skin is oily clean the site with alcohol and

wait till the alcohol dries if the skin is visibly soiled it should be cleaned with soap and water

apply required amount of gel to minimize the skin to electrode impedance

if the healthcare provider is using a ready-made electrode sticky pad then the center of the sticky pad should not be

pressed because it may lead to leakage of electrode jelly next we are going to see a limb leads

limb leads are indicated as ra right arm

l a left arm l l left leg r l for right leg

our a electrode has to be placed near or above the wrist joint or in the right deltoid muscle

l a that is left arm electrode has to be placed near or above the left wrist joint

or in the left deltoid left leg

l electrode has to be placed above the left ankle or in the upper leg right

leg above the right ankle or above the right leg so these are the

placements of limb blades in the right arm

left arm right leg and the left leg

generally avoid placing electrodes over the bony prominences thick muscles or skin folds which could interfere the

wave transmission next chest electrodes

chest electrodes are the electrodes placed over the precordial surface just electrodes are indicated as v1 to

v6 all the six electrodes are placed over the precordial surface at a specific

location v1 the first chest electrode is located or is placed

right fourth intercostal space nearer to the sternum v2

is placed at left fourth intercostal space nearer to the sternum next we are going for v4

v4 is placed left fifth intercostal space at the level of mid clavicular line mid clavicular line

is an imaginary line that falls from the center of the clavicular bone downwards in the thorax

after placing v4 v3 has to be placed in between v2 and v4

next lead is v5 it has to be placed at the level of v4 that is left fifth intercostal space

but at the level of anterior axillary line that is nearer to the anterior axillary

line next v6 v6 is placed

in the same plane as v4 and v5 but at the level of mid axillary line once all lead electrodes

have been applied attach the associated limb and chest leads with a cable for each lead lying inferior to the

electrode this has to be done in order to reduce the tension of the wire we saw about 12 leads are there

limb bleeds chest leads but the collar coding in the leads and the label in the leads are not same universally

there are two different classification of leads are there for its color coding as

well as for its labeling number one is american heart association labeling method

here they are labeled chest cleats as v1 to v6 limb lead as l a

r a l l and r l on the color coding they have indicated as

for chest leads either it is brown or red yellow

green blue orange or purple accordingly similarly for limb leads they have given a color coding

black white red green but there is another

classification which is called as international electro technical commission classification

based on iec label the chest electrodes are labeled as c1 to c6

and limb leads electrodes are labeled as l

r f n similarly the color coding are

white for the chest leads or red yellow green

brown black purple accordingly here for limb leads the color coding for l

it is yellow for r it is red green it is for f it is green for n it is black so you can see the color colors here

for right arm it is white for left arm it is

black for left sorry left leg it is

red for right leg it is green so this picture follows

american heart association labeling method of ecg similarly

if we are using a as per iec label then color code varies accordingly till now we saw about

various ecg leads and its location its color coding its label

now we are going to see how to place the chest electrode exactly in a correct manner

for that there is a technique to identify the various position for that

first the healthcare provider must place the finger over the

patient's tracheal rings that is this area the health care provider has to place

the ring place the finger over the tracheal ring from there slowly the healthcare

provider has to come down the healthcare provider can feel a notch that is a local area which is called as supra

sternal notch after locating suprasternal notch that is from suprasternal notch the

healthcare provider has to come downward which is the sternal bone it contains three parts

manibrium sternite body of the sternum and xiphoid process when the healthcare provider moves the

finger downward he will feel a little elevation or a lump which is called as

angle of loose angle of louise this angle of lewis plays an important landmark in locating

the ecg chest leads angle of louise

the angle of louise corresponds to the second rib on both the side just below the second rib

the space is second intercostal space next

third rib third intercostal space fourth rib fourth intercostal space fifth rib and

fifth intercostal space so in this manner first the healthcare provider must

locate the fourth intercostal space so once if the fourth intercostal space is located

right side nearer to the sternum v one electrode has to be placed exact opposite to the fourth intercostal

space v two has to be placed v4

has to be placed in the fifth intercostal space in between v2 and v4 v3 has to be placed

phi same plane as v four in the at the level of

anterior axillary line v six in the same plane of v four and v five at the level of

mid axillary line so the placement of electrode over the precordial surface is an easy

procedure only thing is the location of an angle of low is is a must that technique has to be

learnt after connecting all the leads we have to adjust the paper speed the normal standard paper speed of an

ecg machine is 25 mm per second the ecg paper runs between voltage

versus time in the x axis it is a time duration in

the y axis amplitude voltage if you see the ecg paper i can see a

small squares with the thin lines and a large square with the thick lines

one small square in a horizontal plane if is equal to 1 mm the duration is

0.04 second so one small square is 0.04 second then for 5 small square is 5 into 0.04

is 0.2 second that is one large square is

0.2 second five large square makes one second that is five into zero point

two second equal to one second so one small square is 0.04 second i am sorry

one small square is 0.04 second one large square is 0.2 second and 5 large square is 1 second this is for the

time duration next if we move on to the voltage 1 milli volt is equal to

10 small square so 10 small square is 1 milli volt

so before recording an ecg the paper speed has to set

25 mm per second still there are other speeds available in the ecg machine like 50 mm per second which is

used particularly at the time of atrial flutter or with a higher heart rate the speed has to be adjusted to

50 mm per second next we move on to the calibration after setting the paper speed

we have to calibrate the ecg machine by pressing a calibration button on the ecg machine

if you press the calibration button one single press that is one millivolt calibration signal is expected to

produce a rectangle of 10 mm height and 5 mm width on both the sides so whenever recording an ecg after

checking the paper speed the ecg machine has to be calibrated and it has to be checked for 1 millivolt calibration

signal whether it is producing 10 mm height and a 5 mm with like this a rectangle with 10 mm height and the 5

mm which this is the standard method to be followed before recording a

ecg because if calibration is not done it may lead to wrong diagnosis and additional

facility is available in the ecg machine is filter depending upon the need the filter can

be switched on or it can be switched off in case if there is an evidence of

somatic muscle interference repeat recording with the filter on and recording made at 0.67 to 40 hertz

always both the sites calibration is advisable that is from the left hand end as well as on the right time

end calibration has to be done next we move on to the artifact artifacts are the electrographic

alteration not related to the cardiac electrical activity this artifact occur in the ecg wave which which may

give a wrong graphical representation so it has to be avoided while recording the ecg

the cause for the occurrence of artifact might be due to poor grounding of the device or interference by the cell phone

or due to electric bits or even due to fluorescent lamps which is present in the ecg room while recording so

fluorescent lamp has to be switched off in case if we get an artifact in the ecg after recording ecg the healthcare

provider must switch off the ecg machine and detach the ecg cable

inform the patient that ecg procedure is over and educate that removal of ecg

electrode may cause mild discomfort so after informing remove the electrodes thank the patient for the ecg recording

then label the ecg paper that is the identification name of the patient date

of birth date of recording sex hospital number indication of an ecg all has to be

mentioned in the ecg paper after the entire procedure wash the hand that is healthcare provider has to wash

their hands with an antiseptic lotion next we can see what are the other ecg devices where ecg can be recorded that

is wearable ecg recording devices among the available ecg recording

devices number one is halter monitor holter monitor is a

portable electrocardiogram which records the electrical activity of the heart for a period of longer

duration that is from a day to even many days this holder monitor is useful in order

to identify certain electrical or ecg changes that cannot be

seen in the excise testing or else to identify irregular heartbeat and palpitation this holder monitor

plays an important role the other wearable devices smartwatch which is available in the market

where it is ecg recording enabled smartwatch it combines everything from a sleep

tracking features to ecg monitor so this presentation is to be used as an agent to

other learning methodologies and not a substitute for appropriate clinical training and qualification i would like

to thank my institute chettinad hospital and research institute and nptel sym for giving me an opportunity for this

presentation and the sources of references that i have used are gayten and genong