LAB MANUAL - InstruConnect · The block diagram of ECG explains: 1) Head Selector switch :- The proportion picked up by the patient , electrode are taken to the lead selector switch

Department of Instrumentation Engineering

LAB MANUAL

Semester-VII

Biomedical Instrumentation

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Institute Vision, Mission & Quality Policy

Vision

To foster and permeate higher and quality education with value added engineering,

technology programs, providing all facilities in terms of technology and platforms for all

round development with societal awareness and nurture the youth with international

competencies and exemplary level of employability even under highly competitive

environment so that they are innovative adaptable and capable of handling problems faced

by our country and world at large.

Mission

The Institution is committed to mobilize the resources and equip itself with men and

materials of excellence thereby ensuring that the Institution becomes pivotal center of

service to Industry, academia, and society with the latest technology. RAIT engages

different platforms such as technology enhancing Student Technical Societies, Cultural

platforms, Sports excellence centers, Entrepreneurial Development Center and Societal

Interaction Cell. To develop the college to become an autonomous Institution & deemed

university at the earliest with facilities for advanced research and development programs

on par with international standards. To invite international and reputed national

Institutions and Universities to collaborate with our institution on the issues of common

interest of teaching and learning sophistication.

Quality Policy

Our Quality Policy

It is our earnest endeavour to produce high quality engineering professionals who are

innovative and inspiring, thought and action leaders, competent to solve problems

faced by society, nation and world at large by striving towards very high standards in

learning, teaching and training methodologies.

Our Motto: If it is not of quality, it is NOT RAIT!

Dr. Vijay D. Patil

President, RAES

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Department Vision & Mission

Vision

To be a premier department for the study of Instrumentation Engineering through

maintaining high quality academic standards, state of art resources and teaching that

promotes students to achieve competencies, exemplary level of employability,

analytical thinking and independent judgment necessary to function responsibly and

successfully in a highly competitive professional and global society.

Mission

Creating knowledge of fundamental principles and innovative technologies

through research within the automation and control areas of Instrumentation

and in collaboration with other disciplines that is distinguished by its

impact on academia, industry and society.

Educating future leaders in academia, industry, and entrepreneurial pursuit,

through a curriculum of theory and application that develops the ability to

solve problems individually and in teams.

Serving the communities to which we belong, at local, national, and

international levels, combined with a deep awareness of our ethical

responsibilities to our profession and society

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Index

Sr. No. Contents Page No.

1. List of Experiments 1

2. Experiment Plan and Course Outcomes 2

3. Study and Evaluation Scheme 3

4. Experiment No. 1 4










1


List of Experiments

Sr. No. Experiments Name

1 To study the different types of electrodes.

2 To study the Electrocardiogram System.

3 Measurement of Blood Pressure using sphygmomanometer.

4 To study Defibrillation.

5 To study Cardiac Pacemaker

6 To study Heart lung machine.

7 To Study and Observe Blood Filtration using Haemodialysis Machine .

8 To study Phonocardiograph System.

9 To study Plethysmograph System.

10 To study X-ray produced by X-ray machine. (Beyond Syllabus).

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Experiment Plan & Course Outcome

Course Outcomes:

CO1 Identify various Bio-potential and their specifications in terms of amplitude and

frequency.

CO2 Understand principle and working of various Biomedical Instruments for diagnosis

applications.

CO3 Decide the applications of therapeutic instruments for treatment purpose.

CO4 Understand applications of imaging instruments and the modalities involved in each

technique.

CO5 Understand significance of electrical safety.

Module

No.

Week

No. Experiments Name

Course

Outcome

1 W1 To study the different types of electrodes. CO1

2 W2 To study the Electrocardiogram System. CO2

3 W3 Measurement of Blood Pressure using

sphygmomanometer.

CO2

4 W4 To study Defibrillation. CO3

5 W5 To study Cardiac Pacemaker CO3

6 W6 To study Heart lung machine. CO5

7 W7 To Study and Observe Blood Filtration using

Haemodialysis Machine

CO5

8 W8 To study Phonocardiograph System. CO4

9 W9 To study Plethysmograph System.

10 W10 To study X-ray produced by X-ray machine. (Beyond

Syllabus) CO3

3


Study and Evaluation Scheme

Course

Code Course Name Teaching Scheme Credits Assigned

ISC702 Biomedical

Instrumentation

Theory Practical Tutorial Theory Practical Tutorial Total

04

02

--

04

01

--

05

Course Code Course Name Examination Scheme

ISC702 Biomedical

Instrumentation

Term Work Oral Total

25 25 50

Term Work:

1. Term work assessment must be based on the overall performance of the student with

every experiment graded from time to time. The grades should be converted into marks

as per the Credit and Grading System manual and should be added and averaged.

2. The final certification and acceptance of term work ensures satisfactory performance of

laboratory work and minimum passing marks in term work.

Oral:

1. Oral exam will be based on the entire syllabus of Biomedical Instrumentation

respectively.

4



Experiment No. : 1

To study the different types of electrodes

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Experiment No. 1

1. Aim: To study the different types of electrodes.

2. What will you learn by performing this experiment?

Biopotential electrodes is a transducer that convert the body ionic current in the body into the

traditional electronic current flowing in the electrode. Biopotential electrode should be able to

conduct small current across the interface between the body and the electronic measuring circuit.

We will get to know Electrical characteristics of biopotential electrodes, Different type of

biopotential electrodes, Electrodes used for ECG, EEG, EMG, and intracellular electrodes.

3. Hardware Required: ECG, EEG, EMG sample electrodes.

4. Theory:

1. Microelectrodes: Electrodes use to measure bioelectric potential near or within a single

cell .

2. Skin surface electrodes: Electrodes used to measure ECG , EMG , EEG potential from

the surface of the skin.

3. Needle electrodes: Electrodes are used to penetrate the skin to record EEG potential

from a local region of the brain or EMG potential from gray.

MICRO ELECTRODES:

There are electrodes with tip sufficiently small to penetrate a single cell in order to obtain

reading from the cell . They have tip diameters ranging from approx 0.05 to10 microns. They

can be formed from solid metal needles.

Types of Microelectrodes:

Metal microelectrodes:

They are formed by electrolytic ethching the tip of a fine tungsten or stainless steel wire with

a desired size then the wire is coated at most to the tip with an insulating material.

6


Fig. 1: Metal Microelectrode

Micropipette microelectrode:

This type is a glass with tip drawn out to desired size it is fitted with an electrolyte

compatible with cellular fluids . It has dual interface.

1. Metal wire in contact with electrolyte solution inside micropipette.

2.Electrode inside the pipette and fluids inside or immediately outside the cell.

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Fig. 2: Glass Micro-pipet electrode

BODY SURFACE ELECTRODES:

Electrodes used to obtain bioelectric potential from the surface of the body are called as body

surface electrodes.

Types of body surface electrodes:

I. Metal plate electrodes:

It consist of a flat metal plate that has bent into a cylindrical segment. A terminal is

placed on its outside surface near 1 end. This terminal is attached to the lead wire to

the EEG.

II. Metal disk electrode:

This electrode which has a lead wire welded to the back surface made up of several

different material. It is coated with electrolyte gel and then passed against patients

chest wall.

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III. Disposable foam pad electrode:

It consist of relatively large disk of plastic foam material with a silver disk on one side

attached to the silver plated snap similar to that of lead wire with female portion is then

snapped on electrode.

Fig. 3: Metal Plate Electrodes

IV. Suction cup electrode:

This electrodes are frequently used in ECG at pre-cardiac levels because they can be

placed at particular location and used to take a recording that consist of a hollow metallic

cylindrical electrode that makes contact with skin at its base. In appropriate technical

form the lead wire is attached to metal cylinder and rubber suction bulb it fits over its

oyher base. Electrolyte gel is placed over the contacting surface of electrodes.

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Fig. 4: Suction Bulb electrode

FLOATING ELECTRODE:

The principle feature of this electrode is that the actual electrode element is released in

cavity so that it does not come in contact with skin itself. Instead the element is

surrounded by electrolyte gel in cavity.

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Fig. 5: Floating Electrode

EARCLIP ELECTRODE:

It is structured electrode used as a reference electrode.

Fig. 6: Earclip Electrode

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INSULATED NEEDLE ELECTRODE:

The basic needle electrode consist of solid needle usually made up of stainless steel with

a sharp point insulated with a coating such as insulating varnish and its tip is exposed.

Types of needle electrodes:

I. Co-axial needle electrode:

It consist of a small gauge hypodermic needle that is modified by running an

insulated fine wire down the centre of its lumen and filling remainder of its lumen

with an electrode material.

II. Bipolar co-axial electrode:

The two wires are placed within lumen of an needle can be connected

differentially so as to be sensitive to electrical activity only in immediate vicinity

of the electrode tip.

Fig. 6: Needle Electrodes

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5. Conclusion and Discussion:

6. QUIZ / Viva Questions:

What are the different types of bio-potential electrodes?

Why are the types of Microelectrodes?

What are the applications of skin surface electrodes?

7. References:

1. Leslie Cromwell, “Biomedical Instrumentation and Measurements”, 2nd

Edition, Pearson

Education, 1980.

2. John G. Webster, “Medical Instrumentation”, John Wiley and Sons, 4th

edition, 2010.

.

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Experiment No. : 2

To study the Electrocardiogram System

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Experiment No. 2

1. Aim: To study the Electrocardiogram System.


Electrocardiography (ECG or EKG) is the process of recording the electrical activity of

the heart over a period of time usingelectrodes placed on the skin. These electrodes detect the

tiny electrical changes on the skin that arise from the heart muscle's electrophysiologic pattern

of depolarizing during each heartbeat. It is a very commonly performed cardiology test.

3. Hardware Required: ECG Machine, Skin surface electrodes.

4. Theory:

The Electrocardiogram (ECG) is a non- invasive test that is used to reflect underlying heart

condition measuring the electrical activity of the heart. By positioning about heart condition can

be learned by looking for characteristics pattern on the ECG.

Fig. 1: ECG Block diagram

https://en.wikipedia.org/wiki/Heart

https://en.wikipedia.org/wiki/Electrode

https://en.wikipedia.org/wiki/Cardiac_muscle

https://en.wikipedia.org/wiki/Electrophysiology

https://en.wikipedia.org/wiki/Depolarization

https://en.wikipedia.org/wiki/Cardiac_cycle

https://en.wikipedia.org/wiki/Cardiology

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The block diagram of ECG explains:

1) Head Selector switch :- The proportion picked up by the patient , electrode are taken to the

lead selector switch. The function of this block is to determine which electrode are necessary for

a particular lead and to connect (+ve) to the remainder of the circuit.

2) Power Amplifier :- It is generally push pull amplifier type differential amplifer. the output of

this amplifier is single ended and applied to the premotor which deflect the righting arm on the

paper.

3) Pre-Amplifier :- This amplifier is usually athree or four stage differential amplifier having a

sufficient large (-ve) current feedback from the end stage to the first stage which gives a

stabilizing effect. The output of this amplifier is given to the power amplifier.

4) Direct Writing Recorder :- The Recorder provides a hard copy of the recorded ECG. It also

prints the patient identificationclinic info, entered by the operator and result of automatic

analysis of ECG.Frequency necessary damping of pen motor and is preset.

5) Auxiliary Circuit :- It provides 1mv calibration signal and automatic blocking of the

amplifier during the change in position of the lead. ECG machine have different no. of leads for

examination. When we go for 12 leads ECG system, then the lead distribution is already

specified on the different places of the body. Here the lead distribution is given as :-

1. One lead for right leg. 2.One lead for left leg.

3. One lead for right arm. 4. One lead for left arm.

5. Six leads for chest. 6. Two for power source.

ECG SIGNAL CONDITIONING:-

An ECG measures the voltage generated by a heartbeat. The signal conditioning challenges

inherent in this application are primarily due to the small signal of only 0.2 mV to 2 mV peak-to-

peak, the 0.05 Hz to 150 Hz bandwidth, and the 50 Hz/60 Hz interference. Analog Devices offers

a wide range of solutions to help design engineers overcome these challenges.

For signal acquisition challenges in this application, an instrumentation amplifier (in-amp) offers

the ability to reject common-mode signals. The AD8220 is a JFET in-amp with low input bias

current of 10 pA and high CMRR at dc and ac with RFI immunity. It operates from a single 5 V

supply–ideal for a portable application. The AD8220 is available in an 8-lead MSOP.

ECG applications require a small footprint and uncompromised ADC performance at low power

per conversion. The AD7980 provides 16-bit resolution, samples up to 1 MSPS, and achieves

±22 ppm INL max–all at only 7 mW power consumption. It is available in a 10-lead LFCSP.

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The serial output of the AD7980 is easily isolated from the system with the ADuM240x iCoupler

digital isolator. iCoupler products, based on chip-scale micro transformer isolation, eliminate

design difficulties commonly associated with optocouplers that employ LEDs and photodiodes.

Typical optocoupler concerns include uncertain current transfer ratios, nonlinear transfer

functions, and temperature and lifetime effects–none of which are issues for iCoupler devices

that have simple digital interfaces and stable performance characteristics.

Fig. 2: ECG Signal Conditioning

Why ECG is performed :-

• ECG leads are attached to the body while the patient lies flat on a bed or table.

• ECG can be performed as a part of physical examination or screening evolution.

• ECG can be performd as a part of cardiac execution test.

• As apart of the evolution of symptoms of chest patient, shorten of breath etc

5. Procedure/ Program:

1. ECG leads are attached to the body while patient lies flat on a bed or table leads

are attached to each extremely and fit to predefined postion on the chest front.

2. The leads are attached to the small suction cup, straps or by small patched

electrodes attached loosely to the skin.

3. This test takes 15 minutes and is painless.In some instances men may require the

shaving of small amountof chest hair to obatin optimal amount between

electrodes, lead and skin.

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6. Results:

PARAMETER STANDARD VALUE OBSERVED VALUE

P Wave 0.25

Q Wave 1.60

R Wave 0.4

T Wave 0.1 to 0.5

PARAMETER STANDARD VALUE OBSERVED VALUE

PR Interval 0.12 to 0.25

QR Interval 0.25

ST Interval 0.05 to 0.1

QR Interval 0.095



Which electrodes are useful for ECG measurement?

Explain ECG Block Diagram.

18


9. References:


Edition,

Pearson Education, 1980.


edition, 2010.

19



Experiment No. : 3

Measurement of Blood Pressure using

sphygmomanometer

20


Experiment No. 3

1. Aim: To Measurement of Blood Pressure using sphygmomanometer.


an instrument for measuring blood pressure, typically consisting of an inflatable

rubber cuff which is applied to the arm and connected to a column of mercury next

to a graduated scale, enabling the determination of systolic and diastolic blood

pressure by increasing and gradually releasing the pressure in the cuff.

3. Hardware Required: Mercury column setup, pressure cuff, needle valve, rubber bulb,

and stethoscope.

4. Theory:

Fig. 1: sphygmomanometer

http://www.google.co.in/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAcQjRxqFQoTCK2F2oOXrcgCFYwYjgodw7INXw&url=http://wallpaper222.com/explore/sphygmomanometer-diagram/&psig=AFQjCNECN50Y0APtlmNQ8fvPu4RybAEkYA&ust=1444198

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A sphygmomanometer , blood pressure meter, blood pressure monitor or blood pressure

gauge is a device used to measure blood pressure, composed of an inflatable cuff to collapse and

then release the artery under the cuff in a controlled manner, and a mercury or

mechanical manometer to measure the pressure. It is always used in conjunction with a means to

determine at what pressure blood flow is just starting, and at what pressure it is unimpeded.

Manual sphygmomanometers are used in conjunction with a stethoscope.

The word was coined from the "pulse", plus the scientific term manometer , i.e. "pressure

meter", itself coined from "thin, sparse", The device was invented by Samuel Siegfried Karl

Ritter von Basch in 1881. Scipione Riva-Rocci introduced a more easily used version in 1896.

In 1901, Harvey Cushing modernized the device and popularized it within the medical

community.

A sphygmomanometer consists of an inflatable cuff, a measuring unit (the mercury manometer,

or aneroid gauge), and a mechanism for inflation which may be a manually operated bulb and

valve or a pump operated electrically.

5. Procedure/Program:

• Remove the cuff, stethoscope, pressure gauge and bulb from the kit, taking care to

untangle the various tubes.

• Sit down on the table where you can easily get your arm to that when you bend your

elbow, it is parallel to your heart.

• Wrap the cuff around your upper arm, slipping the top part of the cuff through the metal

bar that is attached to the cuff.

• Make sure the cuff is snug but not too tight, if your blood circulation stops and you are

going to get an alarming blood pressure reading.

• Gently put the ear piece of stethoscope in your ears.

• Place the wide head of the stethoscope (the diaphragm) entirely on your skin just above

the elbow on the branchial artery.

• If the pressure gauge is attached to cuff, unclip it and attach to something steady you can

see the deflection.

• Take the rubber bulb and tighten the valve and the base.

• Pump the bulb using slow and steady pressure until the needle on gauge is at about 20-30

https://en.wikipedia.org/wiki/Blood_pressure

https://en.wikipedia.org/wiki/Cuff

https://en.wikipedia.org/wiki/Mercury_(element)

https://en.wikipedia.org/wiki/Manometer

https://en.wikipedia.org/wiki/Stethoscope

https://en.wikipedia.org/wiki/Manometer

https://en.wikipedia.org/wiki/Samuel_Siegfried_Karl_Ritter_von_Basch

https://en.wikipedia.org/wiki/Samuel_Siegfried_Karl_Ritter_von_Basch

https://en.wikipedia.org/wiki/Scipione_Riva-Rocci

https://en.wikipedia.org/wiki/Harvey_Williams_Cushing

https://en.wikipedia.org/wiki/Pressure_measurement#Liquid_column

https://en.wikipedia.org/wiki/Pressure_measurement#Liquid_column

22


points above your systolic (top) no. you should release the valve with hand on your cuff

arm and hold stethoscope with free arm.

• As you watch the needle fall back down the gauge , listen for thamping sound.

• Keep watching the gauge and listen to the beats.

• If you miss the exact measure of either number its perfectly acceptable to pump the cuff

back up little to catch it.

6. Results:

SR. NO. DIASTOLIC

(mm of Hg)

SYSTOLIC

(mm of Hg)

PULSE PRESSURE

(mm of Hg)

1

2



What is sphygmomanometer?

What is the value of Diastolic and Systolic blood pressure?

23


2. References:


Edition,



edition, 2010.

24



Experiment No. : 4

To study Defibrillation

25


Experiment No. 4

1. Aim: To study Defibrillation.


Defibrillation is a common treatment for life-threatening cardiac

dysrhythmias and ventricular fibrillation. Defibrillation consists of delivering a

therapeutic dose of electrical current to the heart with a device called a defibrillator.

This depolarizes a critical mass of the heart muscle, terminates the dysrhythmia and

allows normal sinus rhythm to be reestablished by the body's natural pacemaker, in

thesinoatrial node of the heart.

3. Hardware Required: Defibrillator equipment.

4. Theory:

Defibrillation is a process in which an electronic device is used to give an electronic

shock to the heart. This helps in re-establishing normal contraction rhythm in the heart.

Figure 1: Defibrillator Equipment

https://en.wikipedia.org/wiki/Cardiac_dysrhythmia

https://en.wikipedia.org/wiki/Cardiac_dysrhythmia

https://en.wikipedia.org/wiki/Ventricular_fibrillation

https://en.wikipedia.org/wiki/Normal_sinus_rhythm

https://en.wikipedia.org/wiki/Cardiac_pacemaker

https://en.wikipedia.org/wiki/Sinoatrial_node

26


Fibrillation: Heart is able to perform its normal pumping action only through precisely

synchronized action of heart muscle fibers. Two chambers of atria contract together and pump

the blood through two valves into the ventricles. After specific time delay, ventricular muscles

are synchronously activated to pump the blood through the pulmonary and circulatory system.

The condition in which this necessary synchronism is lost is called ‘fibrillation’. During

fibrillation, normal rhythmic contractions of either atria or ventricles are replaced by rapid

irregular twitching of the muscular wall. Fibrillation of arterial muscles is called ‘atrial

fibrillation’. Fibrillation of ventricles is called ‘ventricle fibrillation’.

Atrial Fibrillation: Under the condition of atrial fibrillation, two ventricles can still

function normally, but they respond with an irregular rhythm. Since, most of the blood flow into

the ventricles occurs before atrial contraction.

Ventricular Fibrillation: Ventricular fibrillation is far more dangerous. Under this

condition ventricles are unable to pump blood. If fibrillation is not corrected death will take place

within few minutes.

Types of Defibrillators:-

1. AC defibrillators.

2. DC defibrillators.

AC Defibrillators:

Most successful method of defibrillation is the application of electric shock to the area of

the heart. If sufficient current to stimulate muscles of heart for a brief period, after which normal

heart action may resume. Defibrillator operates at 60Hz frequency to the chest of the patient

(through appropriate electrodes). This application of an electrical shock to resynchronize the

heart is sometimes called counter shock. This method of counter shock is known as ac

defibrillation. AC defibrillation is useful to correct ventricular fibrillation. It is not useful to

correct atrial fibrillation because it will result in more serious ventricular fibrillation. Hence AC

defibrillators are no longer used.

DC Defibrillators:

In this method, a capacitor is charged to a high dc voltage and then rapidly discharged

through electrodes across the chest of the patient. This method is useful for correcting both the

atrial and ventricular fibrillation

27


CIRCUIT DIAGRAM:

Fig. 2. Circuit Diagram

Fig. 3. DC defibrillator discharge waveform

Fig. 4. Truncated Defibrillator discharge waveform

28


Fig 5. Dual Peak monophasic waveform

In this amount of electrical energy discharged by capacitor may range between 100 and

400 w/sec or joules. Duration of discharge is 5 msec. Energy delivered is represented by

waveform shown in fig 2. Area under the curve is proportional to the energy delivered. Peak

value of current is nearly 20A. Curve is monophasic because most of the excursion is above the

baseline. Inductor in the circuit is to shape the wave, to eliminate sharp undesirable current

spikes that would otherwise occur at the beginning of the discharge.



What is fibrillation?

What is the difference between fibrillation and defibrillation?

7. References:


Edition,



edition, 2010.

29



Experiment No. : 5

To study Cardiac Pacemaker

30


Experiment No. 5

1. Aim: To study Cardiac Pacemaker.


The Pacemaker is an electric stimulator that produces periodic electric pulses. That pulse

is to electrodes located on the surface (externally) on the heart. The stimulus thus

conducted to the heart & heart contract, this electric stimulation effect can be used in

which the heart is not stimulated at a proper rate on its own.

3. Hardware Required: Pacemaker medical equipment.

4. Theory:

A pacemaker (or artificial pacemaker, so as not to be confused with the heart's

natural pacemaker) is a medical device which uses electrical impulses, delivered by electrodes

contracting the heart muscles, to regulate the beating of the heart.

The primary purpose of a pacemaker is to maintain an adequate heart rate, either because the

heart's natural pacemaker is not fast enough, or because there is a block in theheart's electrical

conduction system. Modern pacemakers are externally programmable and allow a cardiologist to

select the optimum pacing modes for individual patients. Some combine a pacemaker

and defibrillator in a single implantable device. Others have multiple electrodes stimulating

differing positions within the heart to improve synchronisation of the lower

chambers (ventricles) of the heart.

Fig. 1. Cardiac Pacemaker


https://en.wikipedia.org/wiki/Cardiac_pacemaker

https://en.wikipedia.org/wiki/Electrode


https://en.wikipedia.org/wiki/Heart_rate

https://en.wikipedia.org/wiki/Electrical_conduction_system_of_the_heart

https://en.wikipedia.org/wiki/Electrical_conduction_system_of_the_heart

https://en.wikipedia.org/wiki/Cardiology

https://en.wikipedia.org/wiki/Implantable_cardioverter-defibrillator

https://en.wikipedia.org/wiki/Synchronization

https://en.wikipedia.org/wiki/Ventricle_(heart)

https://en.wikipedia.org/wiki/Ventricle_(heart)

31


There are 2 types of pacemaker :-

1. Implantable (Internal) Pacemaker

2. External Pacemaker

Implantable pacemaker:

A device that uses electrical impulses to regulate the heart rhythm or to reproduce that rhythm.

An internal pacemaker is one in which the electrodes into the heart, the electronic circuitry and

the power supply are implanted (internally) within the body.

These are used where long term pacing is required because of permanent damaged to prevent

prevent normal self triggering of heart.

Implantable pacemaker, along with its electrodes, entirely implanted beneath the skin. Output

leads are connected directly to heart muscle.

This pacemaker is powered by small batteries, so just beneath the skin, replacement of unit

involve minor surgery.

Entire system is present inside the body, whose sinoatrial node have failed to function properly

and who suffered from permanent heart block because of heart attack.

The SA node is the heart's natural pacemaker. The SA node consists of a cluster of cells that

are situated in the upper part of the wall of the right atrium (the right upper chamber of the

heart). The electrical impulses are generated there. The SA node is also called the sinus node.

External pacemaker:

These are used when the heart block presents as an emergency & its it is expected to be present

for a short time.

It is consist of an externally worn pulse generator connected to electrodes located on or within

myocardium. These pacemakers are used on patient with temporary heart irregularities which

patient having heart blocks.

Ts is pacing especially during cardiac surgery, if the surgery involves the valves replacement.

These pacemaker includes various pulse generators located outside the body, normally

connected through wires introduced into the right ventricle via cardiac catheter.



What is the necessity of Pacemaker?

Discuss types of Pacemaker?

http://www.medicinenet.com/pacemaker/article.htm

http://www.medicinenet.com/script/main/art.asp?articlekey=3668

http://www.medicinenet.com/pacemaker/article.htm

32


7. References:


Edition, Pearson

Education, 1980.


edition, 2010.

33



Experiment No. : 6

To study Heart-Lung Machine

34


Experiment No. 6

1. Aim: To study Heart Lung Machine.


A device used in open heart surgery to support the body during the surgical procedure

while the heart is stopped. The heart-lung machine is often referred to as the "pump", and

does the work of the heart and lungs during the operation.

3. Hardware Required: Hear Lung Machine equipment.

4. Theory:

Operating on the human heart poses problems which inhibited surgery on the heart until the early

1950s. Manipulation of the heart, and opening of its cavities' interferes with its function and its

ability to sustain the circulation. The heart–lung machine is a system which takes over the

function of the heart and the lungs with sufficient safety to maintain life while the heart is

stopped or opened to allow surgery on the coronary arteries or the heart valves, or to allow repair

of congenital abnormalities.

BLOCK DIAGRAM :

Fig 1: Blood flow in Heart Lung machine

35


Theory :

A while in theory it is only necessary to bypass the function of the heart, it soon

became apparent that in practice it is simpler to bypass the function of both the heart and the

lungs. The main components of a heart–lung machine are a pump (to provide the driving force to

the blood in the arterial system), an oxygenator (for exchange of oxygen and carbon dioxide),

and a heat exchanger (to allow control of temperature of the body). The connecting tubing and

filter are other components of the heart–lung bypass circuit. Venous blood is siphoned from the

body via a tube in the right atrium of the heart, or via two tubes in the major veins which

converge on the heart. It is pumped through the oxygenator and heat exchanger, and returned via

a plastic tube into the arterial system of the body usually at the upper portion of the ascending

aorta The design of pump which is in most common use today is the roller pump. A simple

rotating arm carrying rollers which compress a loop of polymeric tubing against a solid surface.

Speed of rotation of the roller-bearing arm is controlled to allow a pumping rate similar to that of

the normal heart at rest (about 2.4 litres/min/m2 body surface or typically about 5 litres/min in an

adult).

There are two main types of oxygenator in use at present. ‘Bubble oxygenators’ expose the

passing blood to a stream of gaseous bubbles composed of 95% oxygen and 5% carbon dioxide.

Gas exchange with the blood occurs on the surface of the bubbles and results in reasonably

normal levels of oxygenation of the blood and maintains carbon dioxide in the normal

physiological range.

Fig. 2: Heart Lung Machine

36


Membrane oxygenators consist of a series of fine tubes which allow diffusion of oxygen and

carbon dioxide between the blood flowing through them and the ventilating gas surrounding

them (or vice versa).The oxygenator also combines with a heat exchanger — a system of tubes

through which the blood passes, surrounded by circulating water at controlled temperature. This

allows the blood temperature to be maintained (counteracting the heat loss during the passage of

blood through the heart–lung machine). It also allows deliberate cooling and subsequent

rewarming of the blood, giving the surgeon the option of reducing, or even stopping, the

circulation of the blood around the body for a period of time with safety, because the oxygen

requirement of the body is reduced by hypothermia. The connecting tubes, the oxygenator, and

the pump tubing are all filled with a physiologically compatible fluid (priming fluid) prior to

final connection with the circulation of the body. Avoidance of air bubbles in the heart–lung

circuit is of vital importance. Exposure of blood to the foreign surfaces of the heart–lung

machine initiates the natural clotting mechanisms of the body, and this must be inhibited by

giving the drug heparin to the patient before allowing the circulation to be taken over by the

heart–lung machine. Normal blood clotting is restored after the operation by the administration

of protamine.



What is the working of Heart Lung Machine?

Why it is called as a Heart-Lung Machine?

7. References:


Edition,



edition,

2010.

37



Experiment No. : 7

To Study and Observe Blood Filtration

using Haemodialysis Machine

38


Experiment No. 7

1. Aim: To Study and Observe Blood Filtration using Haemodialysis Machine

.


Measurement of maximum & minimum speed of peristaltic pump with & without

load.

Flow of Dialysate and Blood flow in dialyser

Measurement of dialysate temperature using thermometer

3. Hardware Required: Haemodialysis trainer kit, Dialyser, Dialysate pump, temperature

sensor PT 100, Heater.

4. Theory:

Haemodialysis is a way of cleansing the blood of toxins, extra salts and fluids through a

dialysis machine called “artificial kidney”. It helps maintain proper chemical balance such as

potassium, sodium and chloride and keeps blood pressure under control. For haemodialysis,

human body is connected to a filter (dialyzer) by tubes attached to blood vessels. The blood

is slowly pumped from body into the dialyzer, where waste products and extra fluid are

removed. The filtered blood is then pumped back into body.

Haemodialysis machine is demonstration type which is microcontroller based using

80c51. It has main unit, dialyser and heater with stand and dialysate pump. Main unit of

haemodialysis comprises of peristaltic pump, temperature controller, LCD display and LED

indication to warn high and low temperature condition, Blood leak and bubble indicator.

LCD display shows temperature of heater and speed of peristaltic pump in bpm. At rear panel

of main unit there is connection for PT100 sensor, heater supply and detectors. Dialyser is

attached with connecting pipes with arrangement to hold blood in tank for dialysate. Dialyser

is standard type which is also used in hospitals.

39


Block diagram of Heamodialysis dialysate pathway.

Haemodialysis Trainer kit with peristaltic pump and connecting pipes.

5. Technical Specifications:

a. Main unit:

i. System: Haemodialysis machine

40


ii. Power supply : 230V, 50Hz

iii. Display: 16x2 LCD display

iv. Indication: Temperature High amd Low, Blood leak and bubble

v. Pump: Peristaltic pump head.

b. Dialyser and Heater stand:

i. Dialyser: standard type

ii. Heater: 500 W

iii. Heater material: Aluminium type

iv. Sensor: PT100

v. Blood and Bubble detector: Optical type

6. Procedure:

a. Attach white board to stand using screws which has indication of flow of blood for

connection of pipes.

b. Fix two 1liter beaker stand at upper side which are for dialysate and pure blood.

c. Fix dialyser holder at right hand side and heater at left hand side for which space is

provided on white board.

d. Attach bubble and blood detector below the dialyser stand for which space is provided on

white board.

e. Connect main unit and dialysate pump with dialyser and heater.

f. Finalize the connection of pipes, PT 100 sensor, bubble and leak detector, heater supply.


41



Explain working of peristaltic pump.

Draw the diagram of dialyser and explain its working.

9. References:


Edition, Pearson

Education, 1980.


edition, 2010.

42



Experiment No. : 8

To study Phonocardiograph System

43


Experiment No. 8

1. Aim: To study Phonocardiograph System.


We will get to know about Phonocardiogram concept, Phonocardiograph system, Phonocardiography and heart

sound measurement system.

3. Hardware Required: Phonocardiograph equipment.

4. Theory:

A phonocardiogram or PCG is a plot of high-fidelity recording of

the sounds and murmurs made by the heart with the help of the machine called

the phonocardiograph; thus, phonocardiography is the recording of all the sounds made

by the heart during a cardiac cycle.

https://en.wikipedia.org/wiki/High_fidelity

https://en.wikipedia.org/wiki/Heart_sounds

https://en.wikipedia.org/wiki/Heart_murmur



44


Fig. 1. Wiggers diagram of various events of a cardiac cycle, including a

phonocardiogram at bottom

The sounds result from vibrations created by closure of the heart valves, there are at least

two: the first when the atrio ventricular valves close at the beginning of systole and the

second when theaortic valve and pulmonary valve close at the end of systole.[3]

It allows

the detection of subaudible sounds and murmurs, and makes a permanent record of these

events. In contrast, the ordinary stethoscope cannot always detect all such sounds or

murmurs, and it provides no record of their occurrence. The ability to quantitate the

sounds made by the heart provides information not readily available from more

sophisticated tests, and it provides vital information about the effects of certain drugson

the heart. It is also an effective method for tracking the progress of the patient's disease.

The technique of listening to sounds produced by the organs and vessels of the body is

called auscultation. The areas at which the heart sounds are heard better are called

auscultation area. The graphic recording of the sounds connected with the pumping

action of the heart is called phonocardiogram. These sounds are produced by vibrations

set up in the blood inside the heart by the sudden closure of valves, movement of heart

wall, closure of walls and turbulence and leakage of blood flow.

Heart sounds: First heart sound (Lub): It is due to closure of mitral and tricuspid valves

which permit the flow of blood from atria into the ventricles i.e. it occur at the end of the

atrial contraction and at beginning of the ventricular contraction. It occurs approximately

0.05 second after the onset of QRS complex and just before ventricular systole. It has

loud deep pitch and is booming in character. It is longer in duration, lower in frequency

(30 - 45Hz) and greater in intensity than the second sound. The duration is 50 to

100msec. The asculatory area i.e. it is best heard at the apex of mid pericardium. Second

heart sound (Dub): It is occurs at the end of ventricular systole due to closure of

semilunar valves (aortic and pulmonary aortic valves) in the arteries leading out of the

ventricles. It occurs at 0.03- 0.05 second after the end of T wave. It has higher pitch than

the first sound and is snapping in character. It has frequency 50 - 70Hz. The duration is

25 to 50msec. The asculatory area i.e. it is best heard in the aortic and pulmonary areas.

Third heart sound: It is due to cessation of ventricular filling. It is heard in children and

patient with left ventricular failure due to rapid inflow of blood from the atria into the

ventricles. The accumulated blood from atria and veins causes the distention and

vibration of ventricles. Frequency is below 30Hz. The duration is 0.1 to 0.2sec. It starts

0.12 – 0.18 second after the onset of second heart sound. The asculatory area i.e. it is best

heard at the apex and left lateral position after lifting the legs. Fourth heart sound or atrial

heart sound : It is produced by the contraction of the atria. It is not audible due to low

amplitude and frequency of vibrations. It occurs immediately before the first heart sound.

https://en.wikipedia.org/wiki/Wiggers_diagram


https://en.wikipedia.org/wiki/Heart_valve

https://en.wikipedia.org/wiki/Systole_(medicine)

https://en.wikipedia.org/wiki/Aortic_valve

https://en.wikipedia.org/wiki/Pulmonary_valve

https://en.wikipedia.org/wiki/Phonocardiogram#cite_note-3

https://en.wikipedia.org/wiki/Stethoscope

https://en.wikipedia.org/wiki/Quantification_(science)

https://en.wikipedia.org/wiki/Pharmaceutical_drug

45


It starts 0.12 – 0.18 second after the onset of P wave. The duration is 0.03 to 0.06 second.

Frequency 10-50Hz. The third and fourth sounds are called diastolic sounds and are

generally inaudible in the normal adult but are commonly heard among children. The

figures shows the time relationships between the first, second and third heart sounds with

respect to ECG.

Uses:

They provide indication of heart rate and its rhythmicity. They also give useful

information regarding effectiveness of blood pumping and valve action.

Murmurs:

It occurs in abnormal hearts between normal heart sounds. They are higher pitched

sounds in 100-600Hz range and are longer in duration compared to normal heart sounds.

The causes of murmurs are 1. High velocity blood flow that occurs through small

opening when there is improper opening of valves. 2. Regurgitation which results when

the valves do not close completely and allow some backward flow of blood. 3. Small

opening in the septum that separates the left and right sides of the heart. This forces the

blood through the opening from the left ventricle into right ventricle bypassing the

systemic circulation.



What is Heart Sound Measurement?

What is Phonocardiogram?

7. References:


Edition, Pearson Education, 1980.


edition,

2010.

46



Experiment No. : 09

To study Plethysmograph System

47


Experiment No. 9

1. Aim: To study Plethysmograph System.


We will get to know about Plethysmograph concept, Plethysmography and blood volume

measurement. A plethysmograph is an instrument for measuring changes in volume within

an organ or whole body (usually resulting from fluctuations in the amount of blood or air

it contains).

3. Hardware Required: Blood volume measuring equipment, Plethysmograph instrument.

4. Theory:

Plethysmography is the determination of blood flow (or other physiological param eters)

by measurement of volume changes of the limb. A typical plethysmograph generates a

waveform similar to the arterial pressure waveform. The advantages include non-invasive

nature of measuring blood volume and flow relatively easily. Applications of

plethysmography related measurements have wide applications, albeit with limited

accuracy.

Fig. 1: Chamber Plethysmography

https://en.wikipedia.org/wiki/Organ_(anatomy)

48


Limb Plethysmography:

Normally, the systolic blood pressure in your arm and leg are similar. The ankle-brachial index

(ABI) is a measurement used to check for potential problems. To calculate your ABI, divide the

highest systolic blood pressure reading from your leg by the highest reading from your arm.

A normal ABI falls between 0.90 and 1.30, according to the National Heart, Lung, and Blood

Institute. If your ABI falls outside this range, you may have a narrow or blocked artery. Your

doctor can order additional tests to determine the exact nature of the problem.

5. Procedure:

a. Connect the instrument to the mains.

b. Connect the transducer to system. Insert the transducer into the transducer socket.

c. Check the display of system, it should display heart rate in bpm, missing pulses count.

d. Check the output waveform on DSO.

6. Observations:

a) Pulse output self test 60bpm

Volt/ Div of DSO Voltage Div Total Voltage Time/ Div of DSO

b) Heart Beat Indication Output

Volt/ Div of DSO Voltage Div Total Voltage Time/ Div of DSO

http://www.nhlbi.nih.gov/health/health-topics/topics/pad/diagnosis

http://www.nhlbi.nih.gov/health/health-topics/topics/pad/diagnosis

49




What is Pethysmography?

What is Blood Volume Measurement?

9. References:


Edition,



edition, 2010.

50



Experiment No. : 10

To study X-ray produced by X-ray

machine

51


Experiment No. 10

1. Aim: To study X-ray produced by X-ray machine.


An X-ray generator is a device used to generate X-rays. It is commonly used

by radiographers to acquire an x-ray image of the inside of an object (as

in medicine or non-destructive testing) but they are also used

in sterilization or fluorescence.

3. Hardware Required: X- ray Machine equipment.

4. Theory:

X-rays were discoverd by german physicist Rontgen.Today imaging with X-ray is most

commonly techniques of a simple chest radiography to a digital sub-angiography or complete

tomography depends upon the use of X-ray. X-rays imaging is based on the function that

varies anatomical structure of body has different densities for the X-rays.when X-ray from

source penetrate section of body the internal body structure of the body.

X-ray are electromagnatic radition located at low wavelength end of electro magnetic

spectrum. The X-ray in medical dignostic region have wavelenth of order 10^-10m.

Propagated by electric and magnetic field. According to quantum theory,energy and

wavelength relation is given by

where h=planks constant= 6.32*10^-34s.

c=velocity of propagated proton.

v=freqency of radiation.

/hchE

https://en.wikipedia.org/wiki/X-rays

https://en.wikipedia.org/wiki/Radiographer

https://en.wikipedia.org/wiki/Medicine

https://en.wikipedia.org/wiki/Non-destructive_testing

https://en.wikipedia.org/wiki/Sterilization_(microbiology)

https://en.wikipedia.org/wiki/Fluorescence

52


PROPERTIES OF X-RAYS :-

1) X-rays have very short wavelength and extremely high energy.

2)Because of high energy then pentrate through the material which rapidly absorb and

reflect visible point.

3)X-ray produce ionization in gas.

4)X-ray inflence electrical properties of liquid and solid.

5)X-ray inflence electrical produce flourescene in certain material to help them.

FIG 1: BLOCK DIAGRAM OF X-RAY MACHINE

53


FIG 2 :X-RAY TUBE.

X-RAY PRODUCTION AND X-RAY MACHINE:-

1)PRINCIPLE OF GENERATION-x-rays are produced whenever electron collide with very

high speed matter and they suddenly stop.

2)X-RAY TUBE-The X-ray tube is simply glass enclosed vaccum tube diode consisting of a

cathode that thermally emits electron and target anode,that attracts these electron.This high

voltage implies that electron to very high speed.

3)COLLIMATOR- It reduces the dose of X-rays to the patient,the beam should not strike any

other part of the body then necessay snaping of X-ray is done with collimator.

4)BUCKY GRID-After X-ray enters a patient some rays are deflected off their straight line by

close encounter with atom.This is called Scattering and causes smearing of the image at the edge

and deteriorates image sharpness.

5)X-RAY FILM (DETECTOR)-After processing the film that has been exposed to X-rays shows

the image of X-rays intensity.however the X-rays sensitivity may be marked improved.

54


6)POWER SUPPLY-The supply is turned on and off to control. X-ray energy and consequently

image contest power supply must be larger to handle several kW of power and kV of volage.

LIMITATION:-

1)It is projection of information in single direction.

2)Only images of dense fibrous tissue like bones are possible.

3)Exposure area is more.

4)Since X-ray have very high energy they may cause danger to body.

5)For producing X-rays very high voltage supply 20Kv to 200Kv is required.



What is working of X-ray machine?

What is X-ray tube filament?

7. References:


Edition, Pearson

Education, 1980.


edition, 2010

55


Documents

LAB MANUAL - InstruConnect · The block diagram of ECG explains: 1) Head Selector switch :- The proportion picked up by the patient , electrode are taken to the lead selector switch