Principles of Medical Electronics and Biomedical Instrumentation

Table of Contents
1. INTRODUCTION
1.1 Electronics and Medicine
1.2 What is Medical Electronics?
1.3 What Medical Electronics is Not
1.4 Man’s Hierarchy of Organization
1.5 The Human Body as One System

2. HUMAN CELL-ACTION POTENTIALS
2.1 Cells and their Structure
2.2 Characteristics of Living Organisms
2.3 General Characteristics of a Human Cell
2.4 Resting Potential
2.4.1 Factors Affecting Ion Diffusion through Membranes
2.5 Nernst Equation
2.6 Electrical Characteristics of the Human Cell
2.7 Bioelectric Potentials-Origin

3. BASIS OF BIOELECTRIC POTENTIALS
A) Cardiovascular System-Electrocardiogram (ECG)
3.1 Blood Circulation
3.2 The Heart and its Mechanical Activity
3.3 Measurement of Absolute Arterial Blood Pressure
3.3.1 Oscillometric Method
3.3.2 Doppler Technique
3.3.3 Finger Blood Pressure Gauge
3.4 Electrical Potentials Generated Within the Heart-origin of the ECG Waveform
3.5 Composition of the ECG

B). The Central Nervous System (CNS)- Electroencephalogram (EEG)
3.6 Human Nerve Cell and Impulse Conduction.
3.7 The Nervous System
3.8 Anatomy of the Brain
3.9 Excitation and Inhibition Potentials
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3.10 The Electroencephalogram
3.11 Evoked Potentials

C) Muscle Action and the Sensory System-Electromyogram (EMG)
3.12 The Motor Unit
3.13 Muscle Action
3.14 The Muscular Servomechanism
3.15 Potential Generated during Muscle Action-EMG

4. BIOPOTENTIAL ELECTRODES
4.1 The Electrode-Electrolyte Interface
4.2 Electrode Types
4.2.1 Surface Metal Plate Electrodes
4.2.2 Needle and Wire Electrodes
4.2.3 Microelectrodes
4.3 Stimulating Electrodes

5. TRANSDUCERS FOR BIOMEDICAL APPLICATIONS
5.1 Classification of Transducers
5.2 Selecting a Transducer
5.3 General Features of a Biomedical Instrumentation System
5.4 Variable Resistance Transducers
5.4.1 Resistive Track Transducers
5.4.2 Application of Resistive Potentiometers
5.4.3 Strain Gauge
5.4.4 Semiconductor Strain Gauges
5.4.5 Applications of Strain Gauge Transducers
5.5 Variable Inductance Transducers
5.5.1 Applications of L VDT
5.6 Variable Capacitance Transducers
5.6.1 Applications of Capacitive Transducers
5.7 Thermoresistive Transducers
5.7.1 Thermistor Linearization
5.8 Photoelectric Transducers
5.8.1 Photoemissive Tubes
5.8.2 Photovoltaic Cell
5.8.3 Photoconductive Cells
5.8.4 Application of Photoelectric Transducers
5.9 Piezoelectric Transducers
5.9.1 Applications of Piezoelectric Transducers

6. BIOMEDICAL AMPLIFIERS
6.1 Basic Requirements
6.2 Differential Amplifier.
6.3 Carrier Amplifier
6.4 Chopper Amplifier
6.5 Phase Sensitive Detector

7. PRINCIPLES OF RECORDERS FOR RECORDING BIOELECTRIC EVENTS
7.1 Characteristics of the Recording System
7.2 The Analog Graphic Recorders-Types
7.2.1 Moving Coil Recorder
7.2.2 Moving Iron Recorder
7.3 Analog Recording Techniques and Equipment
7.3.1 Heated Stylus
7.3.2 The Optical-light
7.3.3 The Ink-jet

8. ELECTROCARDIOGRAPHY
8.1 Electrocardiographic Planes
8.2 Frontal Plane ECG Measurements
8.3 Lead Systems for Recording ECG
8.3.1 Standard Bipolar Leads
8.3.2 Unipolar Leads
8.4 Determination of the Heart-Rate
8.5 Sagittal Plane ECG Measurements
8.6 Electrocardiograph

9. ELECTROENCEPHALOGRAPHY
9.1 Signal Sources 9.Q Input Electrodes
9.3 Placement of Electrodes
9.4 EEG Recording Modes
9.5 Electroencephalograph
9.6 Applications of the EEG
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10. ELECTROMYOGRAPHY
10.1 EMG Electrodes
10.1.1 Surface Electrodes
10.1.2 Needle Electrodes
10.2 The Electromyograph System
10.3 Determination of Conduction Velocities in Motor Nerves
10.4 Quantity of Electricity Associated with Muscle Contraction
10.5 Electroretinograph
10.6 Electroocculograph
10.7 Electrogastrograph

11. RESPIRA TION
11.1 Mechanism
11.2 Spirometer
11.3 Pneumotachography

12 SPECIAL TECHNIQUES FOR MEASUREMENTS OF NONELECTRICAL BIOLOGICAL PARAMETERS
12.1 Electrical Impedance Plethysmography
12.2.1 Audiometry
12.2.2 Anatomy of the Human Ear
12.2.3 Threshold of Hearing
12.2.4 Audiometer
12.2 Audiometry
12.3 Techniques to Aid Observation
12.3.1 Laryngostroboscope
12.3.2 X-rays and Radiography
12.3.3 X-ray Computed Tomography
12.3.4 Diagnostic Ultrasound
12.4 Electromagnetic Flowmeter

13 ELECTRONIC INSTRUMENTS FOR AFFECTING THE HUMAN BODY
13.1 Stimulators
13.1.1 Strength/Duration Curves
13.1.2 Types to Stimulators
13.1.3 An Electrodiagnosticffherapeutic Stimulator
13.1.4 Peripheral Nerve Stimulator
13.2 Defibrillators
13.2.1 Mechanism
13.2.2 AC Defibrillators
13.2.3 Capacitive Discharge DC Defibrillators
13.2.4 Delay-Line Capacitive Discharge DC Defibrillator
13.2.5 Square-Wave Defibrillator
13.2.6 Defibrillator Electrodes
13.2.7 Defibrillator Analyer
13.3 Pacemakers
13.3.1 Types of Pacemakers
13.3.2 Modes of Operation
13.4 Diathermy
13.4.1 Shortwave Diathermy
13.4.2 Microwave Diathermy
13.4.3 Ultrasonic Diathermy
13.4.4 Surgical Diathermy
13.5 Respirators
13.6 Blood Pumps
13.7 Myoelectric Control of Paralysed Muscles

14. BIOTELEMETRY
14.1 Physiological Parameters Adaptable to Biotelemetry
14.2 Elements of the Biotelemetry System
14.3 Principles of Design of the Biotelemetry System
14.4 Single Channel Radio Telemetry System
14.5 Transmission of ECG by Telemetry
14.6 Transmission of Blood Pressure by Telemetry
14.7 Telephone Links

15. PATIENT MONITORING AND INTENSIVE CARE SYSTEM
15.1 System Arrangement
15.2 Information Transmission System
15.3 Resuscitation Unit

16 PATIENT SAFETY AND ELECTROMEDICAL EQUIPMENT
16.1 Physiological Effects of Electrical Currents
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16.2 Macroshock and Microshock
16.3 Preventive Measures to Reduce Shock Hazards
16.4 Maintaining Safe Patient Electrical Environment
16.5 Earth-free Patient Monitoring
16.6 Standards

17 COMPUTER APPLICATIONS IN MEDICINE
17.1 Hospital Administration
17.2 Clinical Tests
17.3 Laboratory Tests
17.4 Computer-assisted Medical Imaging
17.5 Computerised Aid to the Physically Handicapped
17.6 Medical Diagnosis and Decision Making
17.7 Patient Monitoring
17.8 Patient Management

18 THE HOSPITAL AND THE MEDICAL ELECTRONICS DEPARTMENT
18.1 Medical Responsibility
18.2 Using Equipment
18.3 Design of Electromedical Equipment
18.4 Technical Responsibility
18.4.1 Servicing Priorities and Conditions
18.4.2 Preventive Maintenance
18.5 Administrative Responsibility
18.6 Hospital Responsibilities
18.7 The Medical Electronics Department (MED)
18.7.1 One MED
18.7.2 The MED within the Engineering Department
18.8 Resident Technical Personnel
18.8.1 The Medical Electronics Technician
18.8.2 The Medical Electronics Engineer
18.8.3 The Technical Administrator
18.9 First and Last, the Patient

Bibliography
Index