Veterinary Anesthetic and Monitoring Equipment

List of Contributors xvii

Preface xxi

1 Medical Gas Cylinders and Pipeline Systems 1 Carl Bradbrook

1.1 Medical Gas Cylinders 1

1.2 Liquid Oxygen Tanks 8

1.3 Oxygen Concentrators 9

1.4 Medical Gas Pipeline Systems 9

References 15

2 Oxygen Concentrators 17 Allan Williamson

2.1 Introduction 17

2.2 Function 17

2.3 Product Gas 17

2.4 Clinical Use 18

2.5 Advantages 20

2.6 Disadvantages 20

2.7 Hazards 20

2.8 Summary 21

References 21

3 Small Animal Anesthetic Machines and Equipment 23 Craig Mosley and Amanda Shelby

3.1 Introduction 23

3.2 Safety and Design 23

3.3 The Basic Veterinary Anesthetic Machine 23

3.4 Breathing Systems 33

3.5 Waste Gas Scavenge Systems 33

3.6 Routine Anesthesia Machine Checkout Procedures 33

References 34

4 Large Animal Anesthesia Machines and Equipment 35 Amanda Shelby

4.1 History of the Large Animal Anesthesia Machine 35

4.2 Purpose 35

4.3 Standards 35

4.4 Similarity to Small Animal Machines 35

4.5 Components of the Anesthesia Machine 36

4.6 Large Animal Anesthesia Workstations 41

4.7 Common Commercially Available Machines 41

4.8 General Cautions 51

4.9 Miscellaneous Equipment for Large Animal Anesthesia 51

References 53

5 Anesthetic Vaporizers 55 Sharon Fornes, Kristen G. Cooley, and Rebecca A. Johnson

5.1 Introduction 55

5.2 Vaporizer Physics 55

5.3 Vaporizer Classification 56

5.4 Other Factors Affecting Vaporizers 62

5.5 Maintenance and Repair 64

5.6 Current Vaporizer Standards 65

5.7 The Modern Vaporizer 65

5.8 Specific Vaporizers 66

5.9 Summary 71

References 71

6 Anesthetic Ventilators 73 Katrina Lafferty

6.1 Introduction 73

6.2 Ventilator Function in the Breathing Circuit 73

6.3 Tidal Volume Delivery 73

6.4 Driving Gas 74

6.5 Bellows Construction 75

6.6 Pressure Limiting Controls 76

6.7 Gas Pressure Alarm 77

6.8 Exhaust Valve 77

6.9 Spill Valve 77

6.10 Ventilator Hose Connection or Ventilator Hose Switch 77

6.11 Ventilation Modes 78

6.12 Cleaning and Sterilization 79

6.13 Pressure Checking 79

6.14 General Concerns and Troubleshooting 80

6.15 Pediatric Ventilation 81

6.16 Basic Ventilator-Patient Set-up 82

6.17 Small Animal Mechanical Ventilators 82

6.18 Large Animal Mechanical Ventilators 85

6.19 Conclusion 89

References 89

7 Humidification and Positive Pressure Equipment 91 Stephanie Keating and Stuart Clark-Price

7.1 Humidification 91

7.2 Positive Pressure Equipment 96

References 98

8 Waste Anesthetic Gas Collection and Consequences 101 Heidi Reuss-Lamky

8.1 Introduction 101

8.2 Occupational WAG Exposure 101

8.3 Physical Properties and Elimination 102

8.4 Pharmacodynamics 102

8.5 History of Governmental Regulations and Trace (Waste) Gas Exposure 104

8.6 WAG Exposure Level Recommendations 104

8.7 Reducing Environmental WAG Exposure 104

8.8 The Anesthetist's Responsibility 107

8.9 Monitoring WAG Exposure 112

8.10 Summary 112

References 113

9 Hazards of the Anesthetic Delivery System and Operating Room Fires 115 Odette O

9.1 Hazards of the Anesthetic Delivery System 115

9.2 Operating Room Fires 123

References 125

10 Components of the Breathing System 127 Craig Mosley and Amanda Shelby

10.1 Breathing Systems 127

10.2 Summary 139

References 139

11 Mapleson Breathing Systems 141 Tatiana Ferreira

11.1 Introduction 141

11.2 Fresh Gas Flows (FGFs) 141

11.3 Advantages and Disadvantages 141

11.4 Choice of System 143

11.5 Specific System Types 143

11.6 Combined Systems 150

11.7 Respiratory Gas Monitoring 150

11.8 Potential Hazards 151

References 152

12 The Circle System 155 Geoffrey Truchetti and Trish Anne Farry

12.1 Introduction 155

12.2 Components 155

12.3 Component Arrangement 162

12.4 Gas Flow 164

12.5 Resistance and Work of Breathing in the Circle System 166

12.6 Dead Space 166

12.7 Heat and Moisture 167

12.8 Maintenance 167

12.9 Advantages/Disadvantages 168

References 168

13 Laryngoscopes 171 Erin Wendt-Hornickle

13.1 History 171

13.2 Laryngoscope Use 171

13.3 Description 171

13.4 Fiber Optic Endoscopes 174

13.5 Veterinary-Specific Laryngoscopes 175

13.6 Summary 175

References 176

14 Supraglottic Airway Devices and Tracheal Tubes and Stylets 177 Jennifer Sager

14.1 Introduction 177

14.2 Laryngeal Mask Airway (LMA) 177

14.3 Veterinary-gel (v-gel®) Airway Device 178

14.4 Endotracheal Tubes 179

14.5 Large Animal Endotracheal Tubes 184

14.6 Reinforced Tubes 185

14.7 Laser Safe Tubes 185

14.8 Single Lung Intubation 186

14.9 Stylets 187

14.10 Cuff Pressure Manometers 188

14.11 Summary 190

References 190

15 Oxygen Delivery Systems 193 Jonathan Bach

15.1 Introduction 193

15.2 Oxygen Supplementation Techniques 193

15.3 Hyperbaric Oxygen 197

References 197

16 Gas Monitoring 199 Louise O'Dwyer

16.1 Introduction 199

16.2 Capnometry/Capnography 199

16.3 Oxygen Measurement 207

16.4 Nitrous Oxide and Inhalation Agent Analyzers 208

16.5 Blood Gas Analysis: Partial Pressures of Oxygen and CO2 210

16.6 Conclusion 210

References 210

17 Airway Volumes, Flows and Pressures 213 Andrew Claude and Alanna Johnson

17.1 Introduction 213

17.2 Definitions 213

17.3 Volume and Flow Measurement Devices 214

17.4 The Ventilatory (Respiratory) Cycle 218

17.5 Airway Pressure Monitoring 219

17.6 Spirometry Loops 219

References 222

18 Pulse Oximetry 223 Odette O

18.1 Introduction 223

18.2 History 223

18.3 Importance of Pulse Oximetry 223

18.4 Function 224

18.5 Pulse Oximeter Probes 224

18.6 Uses 225

18.7 Oxyhemoglobin Dissociation Curves in Different Species 225

18.8 Patient Factors 226

18.9 Abnormal Hemoglobin 227

18.10 Sources of Error 227

18.11 Perfusion Index (PI) and Plethysmograph Variability Index (PVI) 228

18.12 Other Pulse Oximeter Models 229

18.13 Low Saturation Alarms 231

18.14 Pulse Oximetry Use in the Recovery Period 231

18.15 Summary 231

References 232

19 Cardiovascular Monitoring 235 Anderson Favaro da Cunha and Rebecca A. Johnson

19.1 Introduction 235

19.2 Definitions 235

19.3 Measurement Techniques 235

19.4 Patient Point of View 244

19.5 Central Venous Pressure (CVP) 245

19.6 Cardiac Output Monitoring 246

19.7 Conclusion 248

References 248

20 Electrocardiography 253 Tracey Lawrence

20.1 Overview 253

20.2 The ECG Machine 253

20.3 Lead Systems 254

20.4 Mean Electrical Axis (MEA) 257

20.5 ECG Cycle 258

20.6 Electrode Placement 260

20.7 ECG Filters 263

20.8 Evaluating the ECG 264

20.9 Equipment Maintenance 268

20.10 Summary 268

References 269

21 Neuromuscular Transmission Monitoring 271 Molly Allen and Rebecca A. Johnson

21.1 Introduction 271

21.2 Neuromuscular Transmission 271

21.3 Peripheral Nerve Stimulation 271

21.4 Monitoring Techniques 275

21.5 Other Equipment 279

References 280

22 Temperature Regulation and Monitoring 285 Caroline Baldo and Darci Palmer

22.1 Introduction 285

22.2 Heat and Thermodynamics 285

22.3 Thermoregulation 285

22.4 Types of Heat Loss 286

22.5 Heat Loss During Anesthesia 287

22.6 Effects of Hypothermia and Hyperthermia 288

22.7 Re-Warming 289

22.8 Temperature Monitoring Devices 290

22.9 Sites of Temperature Monitoring 291

22.10 Warming Devices 293

22.11 Active Warming Devices 293

22.12 Other Techniques to Minimize Heat Loss 298

22.13 High-Risk Heating Methods 299

References 300

23 Fluid Regulation and Monitoring 303 Julie Walker

23.1 Overview of Fluid Physiology 303

23.2 Assessment of Fluid Balance 304

23.3 Advanced Fluid Balance Monitoring Techniques 307

23.4 Fluid Therapy 311

23.5 Equipment for Fluid Therapy 312

23.6 Summary 319

References 319

24 Anesthetic Records 323 Thomas Riebold

24.1 Introduction 323

24.2 Maintaining Anesthetic Records 323

24.3 Monitoring Recommendations 323

24.4 Paper Anesthetic Records 324

24.5 Electronic Anesthetic Records 324

24.6 Transitioning from Paper to Electronic Medical Records 327

24.7 Specific Types of Anesthetic Monitoring Software 328

24.8 Patient Management and Digital Records 330

24.9 Automated Dispensing Systems and Record Keeping 333

References 333

25 Equipment for the Magnetic Resonance Imaging System 335 Kris Kruse-Elliott

25.1 Basic Principles of Magnetic Resonance Imaging 335

25.2 Regulations 337

25.3 MRI Hazard Classification 337

25.4 Types of Metal 338

25.5 Gauss Lines and Safety Zones 338

25.6 Specific Hazards 339

25.7 Compatible MRI Equipment 340

25.8 Anesthetic Machines 340

25.9 Vaporizers 341

25.10 Ventilators 342

25.11 Laryngoscopes 342

25.12 Endotracheal Tubes and Airway Devices 342

25.13 Monitors 342

25.14 Miscellaneous Items 345

25.15 Summary 346

References 346

26 Equipment for Environmental Extremes and Field Techniques 349 David Brunson and Kristen G. Cooley

26.1 Environmental Extremes 349

26.2 Temperature 349

26.3 Atmospheric Pressure 351

26.4 Drug Delivery Systems 352

26.5 Monitoring Equipment 356

26.6 Field Techniques 358

26.7 Anesthesia for Situations with Limited Means 358

26.8 Stress 362

26.9 Summary 363

References 363

27 Equipment Checkout and Maintenance 365 Molly Allen and Lesley Smith

27.1 Introduction 365

27.2 Daily Checks 365

27.3 Other Equipment 373

27.4 End of Case 373

27.5 Preventative Maintenance 374

References 374

28 Equipment Cleaning and Sterilization 377 Cristina de Miguel Garcia and Kristen G. Cooley

28.1 Introduction 377

28.2 The Decontamination Process 378

28.3 Recommendations for Cleaning and Disinfecting Specific Items 384

References 388

29 Unique Species Considerations: Dogs and Cats 391 Turi Aarnes

29.1 Introduction 391

29.2 Intubation 391

29.3 Breathing System 392

29.4 Monitoring 392

29.3 Recovery 393

29.6 Anesthetic Risk 393

References 394

30 Unique Species Considerations: Ruminants and Swine 395 Denise Radkey, Lindsey Snyder, and Rebecca A. Johnson

Part I: Ruminants 395

30.1 Introduction 395

30.2 Handling and Restraint 395

30.3 IV Catheterization 396

30.4 Induction Equipment 397

30.5 Tracheal Insufflation and Demand Valves 403

30.6 Padding and Positioning 404

30.7 Monitoring Equipment 406

30.8 Commercial Anesthetic Machines 408

30.9 Anesthetic Circuit 408

30.10 Anesthetic Recovery 409

30.11 Summary 410

Part II: Swine 410

30.12 Introduction 410

30.13 Handling and Restraint 410

30.14 Intravenous Catheter Placement 411

30.15 Induction Equipment 412

30.16 Monitoring Equipment 414

30.17 Anesthetic Circuit 415

30.18 Anesthetic Recovery 416

30.19 Summary 416

References 416

31 Unique Species Considerations: Equine 419 Carolyn Kerr

31.1 Introduction 419

31.2 Sedation and Pre-Anesthetic Period Considerations 419

31.3 General Anesthesia 426

31.4 Recovery Period 437

31.5 Medical Records 437

References 438

32 Unique Species Considerations: Avian 441 Carrie Schroeder

32.1 Introduction 441

32.2 Anesthetic Considerations 443

32.3 Venous Access 445

32.4 Anesthetic Monitors 446

32.5 Anesthetic Circuits 447

32.6 Maintenance of Body Temperature 448

32.7 Anesthetic Recovery 448

References 449

33 Unique Species Considerations: Rabbits 451 Katrina Lafferty

33.1 Introduction 451

33.2 Intubation 451

33.3 Breathing Circuits 454

33.4 Monitors 454

33.5 Thermal Support 458

33.6 Summary 458

References 458

34 Unique Species Considerations: Rodents 461 Mario Arenillas Baquero and Rebecca A. Johnson

34.1 Introduction 461

34.2 Anesthetic Machines 461

34.3 Anesthetic Induction Chambers 462

34.4 Masks 464

34.5 Endotracheal Intubation and Intubation Devices 466

34.6 Ventilators 469

34.7 Monitoring Equipment 469

34.8 Warming Devices 473

34.9 Summary 474

References 474

35 Unique Species Considerations: Fish and Amphibians 477 Kurt Sladky

35.1 Introduction 477

35.2 Fish and Amphibian Anesthesia: Induction and Maintenance 477

35.3 Anesthetic Monitoring 483

References 486

36 Unique Species Considerations: Reptiles 489 Christoph Mans

36.1 Introduction 489

36.2 Anesthetic Induction 489

36.3 Airway Intubation 489

36.4 Anesthetic Monitoring 491

36.5 Summary 495

References 495

37 Unique Species Considerations: Non-Human Primates 497 Stephen Cital

37.1 General Anatomy 497

37.2 Taxonomy 497

37.3 Immobilizing Equipment 497

37.4 Anesthetic Machines 497

37.5 Monitors 498

37.6 Summary 501

References 502

Index 503