SUBJECT : MEDICAL ELECTRONIC - PowerPoint Presentation

1. SUBJECT : MEDICAL ELECTRONICTrade : Electronic and communication EngineeringYEAR/SEMESTER : 4th sem

2. CELL STRUCTURE A cell is the smallest unit of living tissue. It enables to perform independent fuction. Cell very in size and shape but most of them have similar components. Every cell comprises of Cell membrane CytplasmNucleus

3. DIAGRAM OF CELL

4. HEART AND CIRCULATORY SYSTEMThe heart is a hollow ,muscular organ, roughly of size of one’s first and about 300 grams in weight.It is reddish brown in colour and somewhat conical in form. It is located almost in the middle of the thoraic cavity close to front wall of and between lungs.The heart has four chamber; two ventricles and two atria both right and left.

5. INTERIOR OF HEART

6. CENTRAL NERVOUS SYSTEMNervous system is the system that controls and integrates the function of the human body works in such a manner that the inner organs fucntions evenly, in spite of the ever changing external and internal environment .The Nervous system is classified into two parts as follow:(1) Central nevous system formed by Brain and spinal cord.(2) Peripheral Nervous sytem which include Cranial nerves, Spinal nerves and Autonomic nervous system

7. CENTRAL NERVOUS SYSTEM

8. RESPIRATORY SYSTEMRESPIRATION: Respiration is the process by which lungs inhale oxygen from the air which is then transported by blood to the tissues;and carbon dioxide formed in the tissues during metabolic activity is carried by blood to the lungs to be expired out.Respiration is a very complex process. It is not single step process, but multistep process which involves four stages. These stages are:Ventilation,Intrapulmonary gas mixing, Diffusion, perfusion.

9. RESPIRATORY SYSTEM

10. BODY TEMPERATUREOral is about 98.4 degree or 37 celciusIt is controlled by “Heart Regulating Centre” present in the hypothalamus. It is very important to maintain the body temperature as various metablolic activites in the body occur at this temperature. Eg .After high fever, Patient usually feel week because of denaturation of various proteins present in muscles. So it is important to maintain this body temperature.

11. BIOELECTRODESThe bioelectic signals are the events needed to be picked up from the surface of body before amplification for recorder or display. This is achieved by electodes . The device that converts ionic potential into electronic potential is called bio-electrodes.

12. DIAGRAM OF ELECTRODES

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15. TYPES OF BIO-ELECTRODESThe elctrodes to be used depend upon the anatomical location and the dimensions of the bioelectric generator. Normally electrodes are manufatured usingGerman silver, stainless steel , Platinum carbon, plastic or rubber , Nylon, polymer etcElectrodes are classified on the basis of ELECTRODES ACTIONAPPLICATIONPLACE OF USE

16. ELECTRODE-TISSUE INTERFACESurface contact electrodes are the most commonly used type of electrodes in recording bio-potentials from the surface of the body (e.g. In ECG ,EEG). Almost all the bio-potential electrodes discussed above make use of electodes paste\Jelly or electrolyte between metal electrode and surfaceElectrode tissue interface involves transfer of electrons from the metal phase to an ionic carrier in the electrolyte, a charger double layer from at the interface.

17. PRESSURE TRANSDUCERSA Pressure transducer converts the pressure into an equivalent analog electrical signal. Thus it measure mainly of fluids. The basic principle behind all type of pressure transducer is that the pressure is measured is applied to a flexible diaphgram which get deformed by the action of the pressure exerted on it. This motion of the diaphram is then measured in terms of an electrical signal.Types of pressure transducer (1) Strain gauge prssure transducer(2) LVDT .Linear voltage differential transformer(3) Capacitive pressure transducer(4) Piezo electric pressure transducer

18. TEMPERATURE TRANSDUCERThe human body temperature is one of the oldest known indicators of the general well being of a person . The insturments required for measurement of human body temperature differs very little from the industrial instrument except for The narrow range required for physiological temperature measurement and the size and shape of th sensing elementTwo basic type of temperature of measurement can be obtained from the human body are (1) Systematic temperature measurements (2) Skin surface temperature measurementsTYPE OF TEMPERATURE TRANSDUCERSMercury in glass thermometer,Digital thermometers, Thermocouple , Thermistor and resistance temperature detectors.

19. PULSE SENSORSThe throbbing steady continuous beet with a presistent rhythm of arteries of a person due to heart beat is known as pulse. It can be eaisly felt at the neck , at the wrist etc. The various type of pulse sesnors are used as intergral part of pulse rate measurement system (1) Photoelectric Pulse sensors(A) Barrier Layer Cells .(B) Photoemissive cells (C) Silicon diode detectors.(2) Optical Fiber sensors(3) Strain gauge pulse sensor

20. ELECTROCARDIOGRAM ( ECG)According to the anatomy of the heart. It is divided into four chambers. The two upper chambers, teh left and the right atria, are synchronized to act together, similarrly, the two lower chambers, the ventricles, operate together. The right atrium receives blood from the venis of the body and pumps it into the right ventricles. The right ventricle pumps the blood through the lungs, where it is oxygenated. The oxygenated enriched blood then enters the left atrium, from which it is pumped into the left ventricle. The left ventricles pumps the blood into the arteries to circulate throughout the body. Because the ventricles actually muslces are much larger, more important and do most of teh work than muscles of the atria. For the cardiovascular system to function properly, both the atria and the ventricles must opeate in a proper time

21. BLOCK DIAGRAM OF ECG MACHINE

22. ECG MACHINE Main parts of Ecg machine are :(1) Lead selector (2) Pre-amplifier (3) Pen amplifier (4) Pen-motor (5) Printer (6) Frequency selective feedback network (7) Bridge output circuit (8) Auxiliary Circuit (9) Power switch (10) Buffer amplifier

23. ELECTROENCEPHALOGRAM (EEG)The brain is an enlarged collection of cell bodies and fibers located inside the skull, where it is well protected from light, physical , chemical or temperature shock. The knowledge of the actual function of various parts of the brain is still largely unknown

24. BLOCK DIAGRAM OF EEG

25. ELECTROENCEPHALOGRAM MACHINE(a) Montage (b) Electrode Montage Selector (c) Preamplifier (d) Sensitivity Control (e) Filters (f) Noise (g) Writing Part (h) Paper Drive (i) Channels

26. ELECTROMYOGRAPH (EMG) MACHINEIt is an instrument used for recording th electrical activity of the muscles. Basically it is used to determine.(1) Whether the muscle is contracting or not, or(2) For recording the electrical activity evoked in a muscle by the stimulation of its nerve.It displays the signal on CRO or it can be heard by using a loudspeaker. The EMG is usually recorded by using surface electrode or by using needle electrodes, which are inserted directly into the muscle. The electrodes pick up the potentials produced by the contracting muscle fibres. The singal can then be amplified and displayed or listened.

27. HEART RATE MEASUREMENT Bassicaly heart rate is the frequecny of the cardic cycle. Normally it is calculated determining the number of heart beats per minute or bpm. The normal heart rate measuring range is 0 – 25 beats min. The following techniques can be used to calculate heart rate .By measuring pulse rateBy using a stethoscope By using ECG Signal By using CardiotechometerBY Using Heart rate monitorBy using ausculation By using phonocardiograph

28. BLOOD PRESSURE MEASUREMENTBlood pressure is the lateral pressure exerted by blood on the vessel walls while flowing through it.The heart’s pumping cycle is divied into two major parts : Systole and Diastole Systole is defined as the period of contraction of the heart muscles specifically the ventricular muscles, at which time blood is pumped into the pulmonary artery and the aorta.Diastole is the period of dialation of the heart cavities as they fill with blood.

29. PACEMAKERIt is an artifical device used to stimulate a rhythmic heart beat by using electrical impluse. In other words, pacemaker is a device that is capable of generating artifical impluse and delivering it to the heart for proper functioning of it. The normal beating of the heart is due to triggering pulse that originates in the sinoartial node which is also called natural pacemaker. But in an abnormal situation , the natural pacemaker doesn’t function properly which results in a decrease of the heart rate, increase of heart rate or irregularity of the heart rate. So an artifical pacemaker is required for the normal functioning of the heart. Thus pacemaker is a medical device designed to regulate the beating of the heart , by replacing a defective natural pacemaker or blocked pathway.

30. SAFETY STANDARDSMedical equipment is primarily used for making mea-Surement of physiological parameters of the human body and also when some kind of energy is applied to human body for diagnosis and treatment . Medical instrument have to be physically connected to patient in someway or other. In case it happens to he electronic equipment the possibility of an electric shock hazaed is quite common if adequate measure have not been taken in design of equipment. Also since the equipment is used by non-technically, medical and other staff and their safety needs also to be ensure. Various organizations at national & international level have tissued guidelines about safety and design of medical device

31. DEFIBRILLATOR Defibrillator is a procedure used to treat life treat life theatening conditions that affects the rhythm of the heart such as cardic arrhythmia, ventricular fibrilation and pulses ventricular tacycardia. The machine used too deliver this therapeutic shock to the heart is called defibrillator

32. TYPES OF DEFIBRILLATORS(a) AC Defibrillators(b) DC Defibrillators(c) Internal Defibrillators(d) External Defibrillators

33. GROSS SHOCKGross shock is caused due to a accidental contact of body part with electric wiring. The of electric accidents involve a current path through the victim from one upper limb to the feet or to the opposite upper limb and they generally occur through skin surface. For a physiological effect to take place, the human body act as a electric circuit. Current must enter the body from one part and leave at some other body surface. In this process, three effect occur. These are () Electrical stimulation of the exciable tissue-nerves and muscles() Resistive heating of tissue() Electro-chemical burns and tissue damage for d.c and high voltages.

34. MICROCURRENT SHOCK The threshold of sensation of electric current differs widely between currents applied arm to arm and currents applied internally to the body. In later, a greater % of the current may flow through arterial system dierctly through the heart and require much less current to produce ventricular fibrillation. Such situations are commonly occurs in hospital. Generally. Micro currents shocks results due to () leakage currents in the line operated instruments and() From voltage differences between grounded conductive surface due to large currents in the grounding system