Medical Textiles
Holly Morris and Richard Murray
Contents
Preface…………xvii
Acknowledgements………………………xix
Authors………….xxi
Chapter 1 Introduction………………..1
References………………….3
Chapter 2 The Development of Textiles in Medicine and the Healthcare Environment over Time…….5
2.1 Introduction………5
2.2 Protecting the Patients and the Healthcare Staff……………………6
2.2.1 Patient and Practitioner Safety…..6
2.2.2 The Antiseptic Approach………….8
2.2.3 The Aseptic Approach………………9
2.2.4 Surgical Gloves…………………….. 11
2.2.5 Surgical Masks……………………… 13
2.2.6 Radiation Protection………………. 19
2.2.7 Uniform Wear………………………..20
2.3 Repairing the Patient…………………………. 21
2.3.1 Sutures……. 21
2.3.2 Artificial Tendons/Ligaments…..22
2.3.3 Scaffolds and Tissue Engineering………………………….23
2.3.4 Hernia trusses………………………..24
2.3.5 Mesh…..24
2.3.6 Stents….25
2.4 Maintaining Patient Comfort by Design, Protection and Support, and Personal Hygiene……………26
2.4.1 Patient Comfort – Hospital Ward Design………………..26
2.4.2 Patient Comfort – Physical Support and Protection……. 27
2.4.2.1 Support……………………27
2.4.2.2 Protection………………..28
2.4.3 Patient Comfort – Hygiene………28
2.5 External Artificial Organ Support………..29
2.6 Summary………..29
References………………..30
Chapter 3 Textile Materials for Healthcare and Medical Applications……………35
3.1 Introduction…….35
3.2 Range of Applications………………………..35
3.3 Properties Sought from Textiles for Medical and Healthcare Applications……………………..36
3.4 Fibres, Yarns, and Fabrics…………………..36
3.4.1 Fibres and Filaments………………37
3.4.2 Microfibres and Microporous Fibres………………………38
3.4.3 Nanofibres…………………………….39
3.5 Yarns………………46
3.6 Fabrics……………47
3.6.1 Woven Fabrics……………………….47
3.6.2 Knitted Fabrics………………………49
3.6.2.1 Weft-Knitted Fabrics……………………………..49
3.6.2.2 Warp-Knitted Fabrics…………………………….51
3.6.3 Non-woven Fabrics…………………52
3.6.4 Braids…54
3.6.4.1 Types of Braid………….54
3.6.4.2 Tubular Braids…………56
3.7 Summary………..57
References………………..58
Chapter 4 Fibre Types and the Polymers Used in Medical Textiles………………..63
4.1 Introduction…….63
4.2 Natural Fibres and Filaments………………63
4.2.1 Animal-Based: Protein Fibres….63
4.2.1.1 Wool……………………….63
4.2.1.2 Silk…………………………65
4.2.2 Plant-Based: Cellulose Fibres…..66
4.2.2.1 Cotton…………………….66
4.2.2.2 Other Cellulose Fibres: Kapok, Hemp, Flax, Sisal, Manila……67
4.2.3 Natural-Polymer Man-Made Fibres……………………….69
4.2.3.1 Protein Fibres: Casein, Collagen……………..69
4.2.3.2 Cellulose Fibres: Viscose Rayon, Lyocell……70
4.2.3.3 Calcium Alginate……..72
4.2.3.4 Chitosan………………….73
4.2.3.5 Hyaluronan/Hyaluronic Acid………………….74
4.2.4 Natural Polymer Elastomer: Rubber………………………74
4.3 Synthetic Polymer Fibres and Filaments: Commodity Types……..75
4.3.1 Nylon….75
4.3.2 Polyester……………………………….77
4.3.3 Polypropylene………………………..79
4.3.4 Acrylic…….80
4.4 Synthetic Polymer Elastomers……………..81
4.5 Synthetic Polymer High-Performance Fibres and Filament Materials and Other Specialist Polymer Structures…………………………….81
4.5.1 Aramids………………………………..81
4.5.2 Ultra-High Molecular Weight Polyethylene (UHMWPE)………………………….82
4.5.3 Cross-Linked Polyethylene………84
4.5.4 Dendritic Polymers…………………85
4.6 Synthetic Absorbable Polymers (SA Polymers)…………………..86
4.6.1 Aliphatic Polyesters………………..86
4.6.2 Polyurethanes………………………..87
4.7 Super-Absorbent Polymers………………….89
4.8 Electroactive Polymer Fibres……………….90
4.8.1 Conductive Polymers………………90
4.8.2 Piezoelectric Polymers……………90
4.8.3 Photovoltaic Materials…………….91
4.8.4 Electrets………………………………..91
4.9 Other Materials…….92
4.9.1 Carbon Fibres………………………..92
4.9.2 Glass…..93
4.10 Summary………..93
References………………..94
Chapter 5 Medical Textiles: Finishing…………………………105
5.1 Introduction…..105
5.2 Antimicrobial Finishes……………………..107
5.2.1 Inorganic Antimicrobial Finishes………………………..114
5.2.2 Organic Antimicrobial Finishes…………………………..118
5.2.3 Other Finishes……………………..121
5.2.3.1 Fluid-Repellent Finishing……………………..121
5.2.3.2 Plasma Treatment…..121
5.2.3.3 Chitosan………………..122
5.2.3.4 Cyclodextrins…………122
5.2.4 Molecular Imprinting……………124
5.3 Multifunctional Finishing of Medical Textiles………………….124
5.4 Antimicrobial Testing of Finishes………125
5.4.1 Qualitative Antibacterial Tests…………………………….125
5.4.2 Quantitative Antibacterial Tests…………………………..125
5.4.2.1 ISO 20743: Quantitative Test Methods to Determine the Antibacterial Activity of All Antibacterial Textile Products……….126
5.5 Antiviral Testing of Finishes……………..126
5.5.1 Test Methods Using a Surrogate………………………….126
5.5.2 Test Methods Requiring Tests with Each Individual Virus…………………..127
5.5.3 Suitability of Test Method to Intended Application………………………….128
5.6 Durability Testing of Finishes……………130
5.7 Suitability of Antimicrobial Treatment to Intended Application……130
5.7.1 Mechanisms of Interaction between Antimicrobial Textiles and Pathogens………………….131
5.7.2 Tests for the Effectiveness of Antimicrobial Treatments in Different Applications……………………132
5.7.2.1 Implants………………..132
5.7.2.2 External Applications…………………………..132
5.7.2.3 Furnishings, Fixtures, and Fittings…………135
5.7.3 Predictability of Mismatch between Expectation and Practice……….135
5.8 Sterilisation……136
5.8.1 Physical Sterilisation Methods…………………………….136
5.8.1.1 Moist Heat Sterilisation………………………..136
5.8.1.2 Low-Temperature Sterilisation………………137
5.9 Summary………138
References………………139
Chapter 6 Ensuring Regulatory Compliance………………..147
Peter J. Ogrodnik
6.1 Introduction…..147
6.2 Changes to Legislation……………………..147
6.3 The Medical Devices Bodies……………..148
6.4 Essential Definitions and Changes to These……………………..148
6.5 Classification of Medical Devices………154
6.5.1 Classification Rules………………155
6.5.2 Custom-Made Devices………….157
6.5.3 Exemption?………………………….159
6.5.4 European Union Classification…………………………….159
6.5.5 FDA Classification……………….159
6.6 Risk Management and Risk Analysis….160
6.6.1 Risk Management Process (ISO 14971)………………..160
6.6.2 Risk Analysis……………………….161
6.6.3 Identifying Hazards………………163
6.6.4 Assessing Level of Risk………..165
6.6.5 Other Risk Assessment Methods…………………………173
6.6.6 Risk Management Procedure Document………………174
6.6.7 Risk Management Folder in the Technical File……..175
6.6.8 Risk Management and Internal Procedures…………..176
6.6.9 Software……………………………..177
6.7 Standards, Courses, and Certification…177
6.7.1 Courses and Certification………178
6.8 Biocompatibility………………………………178
6.9 Technical Files……179
References………………179
Chapter 7 Implantable Medical Textiles………………………181
7.1 Introduction…..181
7.2 Desirable Properties in Implantable Medical Textiles………..181
7.3 Sutures………….181
7.3.1 Healing of Wounds……………….184
7.3.2 Advances in Suture Materials……………………………..186
7.4 Vascular Grafts, Stents, and Valves……188
7.4.1 Current Problems with Grafts, Stents, and Valves…………………………..193
7.4.2 Advances with Grafts, Stents, and Valves……………..194
7.5 Implantable Mesh Products……………….195
7.5.1 Tendons and Ligaments…………195
7.5.2 Hernial Repair……………………..201
7.5.2.1 Types of Mesh and Surgical Considerations……….201
7.5.3 Urogynaecology…………………..205
7.5.4 Problems with Mesh……………..206
7.5.5 Future Developments with Mesh………………………….206
7.6 Ophthalmic Uses……………………………..207
7.6.1 Biomaterials………………………..209
7.6.2 Contact Lens………………………..209
7.6.3 Keratoprosthesis…………………..210
7.6.4 Intraocular Implants……………..210
7.6.5 Scleral Buckle in Retinal Detachment Surgery………210
7.6.6 Orbital Implants…………………..211
7.6.7 Viscoelastic Substances (VES)……………………………211
7.7 Resorbable Scaffolds for Cell Growth…211
7.8 Testing of Implantable Medical Textiles…………………………..213
References………………213
Chapter 8 Non-implantable Medical Textiles……………….223
8.1 Introduction…..223
8.2 Wound Dressings……………………………..223
8.2.1 Desirable Properties in Wound Dressings……………..223
8.2.2 Passive Wound Dressings………224
8.2.3 Interactive Wound Dressings…226
8.2.4 Bioactive Wound Dressings……228
8.3 Products Used for Haemostasis………….230
8.4 Pressure Garments……………………………232
8.4.1 Desirable Properties in Pressure Garments…………..232
8.4.2 Engineering the Pressure Garment………………………232
8.4.3 Thromboembolic Devices……..235
8.4.4 Pressure Garments in the Management of Fractures and Soft Tissue Injuries………………………..237
8.4.5 Pressure Garments in the Management of Burns…….240
8.5 Orthotics……….242
8.5.1 Desirable Properties in Orthotics…………………………243
8.5.2 Hernia Trusses……………………..243
8.5.3 Hip Protectors……………………..244
8.5.4 Braces and Splints………………..246
8.5.5 Scoliosis Braces……………………248
8.5.5.1 Management of Scoliosis………………………248
8.5.5.2 Types of Brace……….248
8.5.5.3 Adjuncts to Brace Therapy……………………250
8.5.6 Exoskeletons………………………..250
8.6 Testing of Non-implantable Medical Textiles……………………252
References………………252
Chapter 9 Healthcare, Hygiene, and Personal Protective Equipment (PPE)………261
9.1 Introduction…..261
9.2 Healthcare Equipment………………………262
9.2.1 Desirable Properties in Healthcare Equipment………262
9.2.2 Furniture, Furnishings, and Coverings…………………262
9.2.3 Hospital Sheets, Pads, and Pillowcases…………………263
9.2.4 Air Treatment………………………263
9.2.4.1 Room Sterilisers…….264
9.2.4.2 Air Filters………………264
9.2.4.3 Airflow modelling….266
9.3 Hygiene Products……………………………..267
9.3.1 Desirable Properties in Hygiene Products…………….267
9.3.2 Incontinence Products…………..268
9.3.3 Feminine Hygiene Products…..269
9.3.4 Cloths and Wipes…………………270
9.3.5 Dental Floss…………………………272
9.3.6 Reusability and Disposability of Hygiene Products…………………273
9.4 Personal and Protective Equipment…….274
9.4.1 Desirable Properties in Personal and Protective Equipment……………274
9.4.2 Surgical Gowns, Aprons and Hats……………………….275
9.4.3 Surgical Gloves……………………283
9.4.4 Surgical Masks and Respirators…………………………..284
9.4.5 Healthcare Workers’ Clothing and Uniforms………..291
9.4.6 Patient Clothing……………………295
9.5 Testing of Health and Hygiene Products…………………………..296
9.6 Summary………297
References………………298
Chapter 10 Extracorporeal Devices………………………………311
10.1 Introduction…..311
10.2 Extracorporeal Membrane Oxygenation…………………………..311
10.2.1 Tubing……313
10.2.2 Pump…….313
10.2.3 Oxygenator………………………….314
10.3 The Kidney……316
10.3.1 The Artificial Kidney and Associated Role of Textiles……………………………317
10.4 The Pancreas…318
10.4.1 The Artificial Pancreas and Associated Role of Textiles……………………………319
10.5 Other Devices for the Support of Homeostasis………………….319
10.6 Testing of Extracorporeal Devices……..320
References………………320
Chapter 11 Intelligent (SMART) Medical and Healthcare Textiles………………..323
Simon King and Holly Morris
11.1 Introduction…..323
11.2 Smart Textiles…….323
References………………331
Chapter 12 Case Studies……………335
12.1 Case Study One: PPE and Planning for Emergencies…………335
12.1.1 2020 Vision: Epidemics and Shortages of PPE………335
12.1.1.1 Early Warnings………335
12.1.1.2 Single Use vs Reusable…………………………336
12.1.1.3 Quantity Issues………336
12.1.1.4 Quality Issues………..337
12.1.1.5 Supply Issues…………337
12.1.1.6 Supply-Chain Management Issues………….337
12.1.1.7 Decontamination and Reuse Issues………..338
12.1.2 2020 Hindsight: Prepare for the Next Healthcare Crisis………………….338
12.1.3 Beyond 2020: Planning…………340
References………………341
12.2 Case Study Two: Aortoduodenal Fistula after Endovascular Aneurysm Repair…………343
12.2.1 Discussion…………………………..346
References………………346
12.3 Case Study Three: Nasal Haemostasis……………………………..346
12.4 Case Study Four: Cataract…………………347
12.5 Case Study Five: Risk Analysis Table…349
Chapter 13 Medical Textiles: The State of the Art………….351
References………………355
Index……………357