Table of Contents
PREFACE I
TABLE OF CONTENTS V
CHAPTER 1 OVERVIEW OF GAS MAN® AND ITS USES 1
INTRODUCTION 1
THE GAS MAN APPROACH 3
USES FOR GAS MAN 4
OTHER USERS OF GAS MAN 6
SUMMARY 7
CHAPTER 2 GETTING STARTED WITH GAS MAN® 8
INTRODUCTION 8
YOUR SOFTWARE LICENSE 8
The Single User License 8
The Site License 8
Copying & Distributing the Manual & Software 9
INSTALLING GAS MAN ON WINDOWS™ OR MACINTOSH COMPUTERS 9
Hardware Requirements 9
Installing the Software under a Single User or Site License 9
THE GAS MAN CONTROL, PICTURE, AND GRAPH 10
Setting Parameters 13
THE GAS MAN MENUS & TOOLBAR 14
MAIN MENU 14
THE TOOLBAR 18
WORKING WITH MULTIPLE VIEWS 19
RUNNING A GAS MAN SIMULATION 20
Exercise 2-1: Running a Simple Simulation 20
Exercise 2-2: Replaying and Revising a Simulation 22
USING BOOKMARKS 22
SUMMARY 23
CHAPTER 3 A ONE COMPARTMENT MODEL 24
Exercise 3-1: Wash-in of a Single Compartment 25
Exercise 3-2: = V/F 31
Exercise 3-3: The Shape of the Exponential Curve 33
SUMMARY 34
CHAPTER 4 TWO SEQUENTIAL COMPARTMENTS 35
Exercise 4-1: The Step Response of a Perfectly Mixed Circuit 36
Exercise 4-2: The Alveolar Step Response 37
Exercise 4-3: Wash-in of Two Compartments 39
Exercise 4-4: Using Overpressure 41
SUMMARY 42
CHAPTER 5 THE ALVEOLAR TENSION CURVE 43
Exercise 5-1: The Open Circuit Alveolar Tension Curve 44
Exercise 5-2: The Initial Rise in the Alveolar Tension Curve 45
Exercise 5-3: Lower Ventilation Slows Initial Rise in Alveolar Tension 47
Exercise 5-4: Uptake Produces a Knee and Plateau in Alveolar Tension 48
Exercise 5-5: Increasing Alveolar Ventilation Raises the Knee and Plateau 49
Exercise 5-6: Increasing Cardiac Output Lowers the Knee and Plateau 52
Exercise 5-7a: Ratio of VA to Effective CO Determines Plateau Height 53
Exercise 5-7b: Plateau Increases with VA 55
Exercise 5-7c: Plateau Increases inversely with CO 56
Exercise 5-8: Anesthetic in Venous Blood causes Gently-Rising Tail 58
SUMMARY 61
CHAPTER 6 PLATEAU HEIGHT & BLOOD GAS SOLUBILITY 62
Exercise 6-1: Alveolar Tension Curves Have the Same General Shape 63
Exercise 6-2: High λB/G Drugs Have Low Plateau and A/I or E/I 67
Exercise 6-3: Determining the Initial Overpressure Value 68
Exercise 6-4: Choosing the Solubility-adjusted Overpressure 70
SUMMARY 72
CHAPTER 7 OVERPRESSURE & OPTIMUM ANESTHESIA 73
Exercise 7-1: Maintaining 1 MAC Using Overpressure 74
Exercise 7-2: Optimum Anesthesia Uses Overpressure 77
Exercise 7-3: Optimum Clinical Anesthesia Using Overpressure 81
SUMMARY 85
CHAPTER 8 THE HIGH INSPIRED CONCENTRATION EFFECT 86
Exercise 8-1: The Concentration Effect 87
Exercise 8-2: Concentration Effect Varies with Inspired Concentration 88
Exercise 8-3: At 100%, CO Has No Effect on ALV 89
Exercise 8-4: Concentration Effect depends on Uptake Effect 92
SUMMARY 94
CHAPTER 9 LOW FRESH GAS FLOW ANESTHESIA 95
Exercise 9-1: Reducing Fresh Gas Flow 96
Exercise 9-2: Circuit Flush Is Faster 98
Exercise 9-3: In a Perfect World… 101
SUMMARY 102
CHAPTER 10 CLOSED-CIRCUIT ANESTHESIA 103
Exercise 10-1: Simulating Liquid Injection 104
Exercise 10-2: Liquid Injection Can Produce Optimum Anesthesia 106
Exercise 10-3: Classic Closed-circuit Approach 109
SUMMARY 112
CHAPTER 11 THE SECOND GAS EFFECT 113
Exercise 11-1: at Low Concentration, the Second Gas Effect is Slight 114
Exercise 11-2: at High Concentration, the Second Gas Effect is Dramatic 116
Exercise 11-3: Concentration Effect Using 70% Nitrous Oxide 119
SUMMARY 120
CHAPTER 12 PATIENT WAKE UP 121
Exercise 12-1: Wake Up Is the Inverse of Induction 121
Exercise 12-2: Lower Solubility Means Lowers Alveolar Wake-up Tension 123
SUMMARY 126
CHAPTER 13 PATIENT SIZE 127
Exercise 13-1: Kinetics is Faster in Smaller Patients 128
Exercise 13-2: Kinetics is Faster in Smaller Animals 130
SUMMARY 131
CHAPTER 14 ANALYZING COST 132
Exercise 14-1: Determining Cost to Achieve 1 MAC 133
Exercise 14-2: Cost to Achieve 1 MAC is Lower with Lower FGF 135
Exercise 14-3: Low Flow Techniques with New Agents 138
SUMMARY 141
CHAPTER 15 HIGH FLOW DURING INDUCTION 142
Exercise 15-1: Simulate Anesthesia Induction with FGF 6 LPM 142
Exercise 15-2: Simulate Anesthesia Induction with FGF 2 LPM 144
Exercise 15-3: Induction at 6 L/min is much more rapid than at 2 L/min 145
SUMMARY 146
CHAPTER 16 BOLUS CONTROLLED ANESTHETIC DEPTH 147
THEORY 147
SUMMARY 150
CHAPTER 17 VITAL CAPACITY (DEEP BREATH) INDUCTION 151
Exercise 17-1: Circuit Prime 152
Exercise 17-2: VCI Brings Expired to 2 MAC Immediately, VRG to 1.5 MAC Easily 153
Exercise 17-3: Turning Vaporizer Off Delivers Negative Bolus 154
Exercise 17-4: Achieving 2 MAC in the brain after Vital Capacity Induction 156
SUMMARY 158
CHAPTER 18 VIMA 159
Exercise 18-1: Maintenance of 1 MAC anesthesia until the end of surgery 160
Summary 161
CHAPTER 19 DON'T TURN FGF AND DEL DOWN AS SOON AS END-TIDAL ANESTHETIC CONCENTRATION REACHES THE DESIRED BRAIN ANESTHETIC LEVEL 162
Exercise 19-1: Turning FGF and DEL Down Too Early 162
Exercise 19-2: Maintaining FGF and DEL after ALV Reaches 1 MAC 164
SUMMARY 165
APPENDIX A 166
EVOLUTION OF THE UNDERSTANDING, MODELING & SIMULATION OF ANESTHESIA UPTAKE & DISTRIBUTION 166
APPENDIX B 167
THE GAS MAN APPROACH 167
Model Parameters 168
FURTHER CONSIDERATIONS ON THE USE OF GAS MAN® 169
ORGAN VOLUMES 169
ORGAN BLOOD FLOWS 169
BREATHING CIRCUIT 169
SHUNTS AND DEAD SPACE 170
INTER-TISSUE DIFFUSION 170
SUMMARY 170
APPENDIX C 171
GAS MAN SYSTEM DEFAULTS 171
APPENDIX D 173
GAS MAN VERSIONS & FUNCTIONS 173
APPENDIX E 176
Custom and Customized Anesthetics 176
Program, View, Simulation, Anesthetic, Color and Patient Defaults 178
Bookmarks 183
Saving, Opening, and Sharing Simulations 183
Replaying Simulations 186
Tabs, Windows and Panels (The Model, View, Controller Pattern) 187
Multiple Agent Simulations 189
Circuit flush 192
Scrolling 192
Scaling 193
Using the Overlay Feature 193
Vaporization, injection and uptake 194
The Ideal Circuit 194
Printing and Previewing 195
Exporting to PDF, HTML and XML 195
Capture and Copy 196
BIBLIOGRAPHY 197
