SECTION ITECHNICAL ASPECTS OFMECHANICAL VENTILATION, 1

Chapter 1Classification of Mechanical Ventilators, 1RobertL. Chatbum and Richard D. Branson

Basic Concepts, 2Input Power, 2

Electric, 3Pneumatic, 3

Control Scheme, 3Control Variables, 10Phase Variables, 12Conditional Variables,22Modes of Ventilation, 24Control Subsystems,31Output Waveforms, 35

Ventilator Alarm Systems, 42Input Power Alarms, 43Control Circuit Alarms, 43Output Alarms, 43

Chapter 2

Modes of Ventilator Operation, 49RichardD. Branson

Pressure Control Versus V olume

Control, 50

Pressure Target Versus Volume Target, 50Modes, 51

Continuous Mandatory Ventilation, 51Assist-Control Ventilation, 52Assisted Mechanical Ventilation, 55

Intermittent Mandatory Ventilation, 58Synchronized Intermittent Mandatory

Ventilation, 59

Pressure Support Ventilation, 60Continuous Positive Airway Pressure, 64Airway Pressure Release Ventilation, 66Pressure Control Inverse Ratio

Ventilation, 68

Mandatory Minute Ventilation, 69Combining Modes, 71Dual Control Modes, 71

Dual Control Within a Breath, 71Dual Control Breath-to-Breath-

Pressure-Limited, Flow-CycledVentilation, 73

Dual Control Breath-to-Breath-

Pressure-Limited, Time-CycledVentilation, 73

Automode,74

Adaptive Support Ventilation, 76Adaptive Tidal V olume Support, 78Automatic Tube Compensation, 79Proportional Assist Ventilation, 80SMARTCAREPS,82

Chapter 3The Patient-Ventilator Interface:

Ventilator Circuit, Airway Care, andSuctioning, 89Richard D. Branson

The Ventilator Circuit, 90Ventilation, 90Exhalation Valves, 91

Care of the Artificial Airway, 92Tube Placement, 92

Securing the Tube, 96Special Endotracheal Tubes, 97

Silver-Coated or Silver-ImpregnatedEndotracheal Tubes, 97

Subglottic Suction Endotracheal Tubes, 97Oral Care, 98

Management of the Endotracheal TubeCuff, 98

Monitoring Cuff Pressure, 99Suctioning, 100

Bronchial Suctioning, 101Use of Saline Instillation, 102

Complications of Suctioning, 102Patient-Ventilator System Check, 103

xiü

xiv CONTENTS

Chapter 4

Humidification and Aerosol Therapy, 111Richard D. Branson

Physical Properties, 112Physiologic PrincipIes, 114High-Flow Humidifiers, 115

Types of High-Flow Humidifiers, 116Passive Humidifier, 116Characteristics of Artificial Noses, 119

Moisture Output, 119Resistance, 119

Dead Space, 120Additives, 120Cost, 120Choosing the Right Passive Humidifier, 121

Use of Humidification Devices DuringMechanical Ventilation, 121

Active Hygroscopic Heat and MoistureExchangers, 123

Heat and Moisture Exchanger Booster, 124Aerosol Therapy During Mechanical

Ventilation, 124Physical Properties, 124Types of Aerosol Generators, 125Choosing an Aerosol Delivery System, 128Aerosol Delivery During Mechanical

Ventilation, 128

Monitoring Bronchodilator Efficacy, 130Recommendations for Aerosol Therapy in

Mechanically Ventilated Patients, 132Aerosolized Pharmacologic Agents, 132

Bronchodilators, 132

Anticholinergics, 135Anti-Inflammatory Agents, 136Aerosolized Antibiotics, 137

Chapter 5Ventilator Monitors and Displays, 146Neíl R. MacIntyre

Pressure and Flow Sensors, 147Pressure Sensors, 147Flow and Volume Sensors, 148

Output from Pressure/Flow IV olumeSensors, 149

Monitoring Maneuvers, 149Gas Analyzers and Gas Exchange

Monitors, 151Display Screens, 151Future Sensors and Monitors, 151

Ventilator Alarm Systems, 153Levels ofEvents and Alann Requirements, 153Alarm Cost Effectiveness, 155

SECTION 11

PHYSIOLOGY, 159

Chapter 6Respiratory System Mechanics, 159Neíl R. MacIntyre

Measurements, 159

Lung Inflation and Respiratory SystemMechanics: Equation of Motion, 162

Compliance (Elastance), 162Resistance, 164

Mechanical Loads, 165

Interaction of Respiratory System Mechanicswith Ventilator Settings, 167

Mechanical Determinants of Delivered

Ventilation, 167

Chapter 7Alveolar-Capi/lary Gas Transport, 171Neil R. MacIntyre

Steady-State Alveolar-Capillary PressureGradients, 171

Ventilation-Perfusion Matching, 173Positive Pressure Ventilation Effects on

Ventilation-Perfusion Matching, 174Inspiratory and Expiratory Positive

Pressure, 174

Inspiratory Flow Pattern and Inspiratory-Expiratory Time Relationship, 177

Intrathoracic Pressures and Perfusion, 178

Alveolar-Capillary Gas Transport inthe Context of Overall OxygenDelivery, 178

Chapter 8Patient-Ventilator Interactions, 182Lawrence R. Tom and Catheríne S. H. Sassoon

Determinants of SpontaneousVentilation, 183

Respiratory Control System, 183Equation of Motion, 184

Patient- V entilator Interactions, 185Patient-Related Factors, 185Ventilator-Related Factors, 186

The Future, 193

Chapter 9Cardiopulmonary Interactions, 198David N. Hager and Henry E. Pessler

Mechanical Forces During Ventilation, 199Venous Return, 199Ventricular Interdependence, 199Pulmonary VascularResistance, 200

CONTENTS xv

Pulmonary Vascular Capacitance, 200Ventricular Afterload, 200Stress on Abdominal Vessels, 200

Clinical Applications: Transient Effects, 200Valsalva Maneuver, 200

Respiratory Changes in Pulse Pressure, 201Clinical Applications: Steady-State

Effects, 201PEEP, 201

Weaning, 203

Chapter 10Ventilator-Induced Lung Injury, 206

Renee D. Stapleton and Kenneth P. Steinbert

Alveolar Rupture and Extra-AlveolarAir, 207

Stretch-Induced Lung Injury, 208Experimental and Mechanistic Evidence for

VIL!, 208

Clinical Studies Providing Evidencefor VIL!, 211

Summary, 212

SECTION 111

AD..JUNCTIVE THERAPY, 217

Chapter 11Nutrition,217

Richard D. Branson and jay A. johannigman

Malnutrition in the MechanicallyVentilated Patient, 218

Effect of Underfeeding, 218Effect of Overfeeding, 219Nutritional Assessment, 220

Nutritional Requirements, 221Performance of Indirect Calorimetry, 222Design of the Nutrition Support

Regimen, 225Monitoring Response and Patient

Tolerance, 229Conclusions, 230

Chapter 12Sedation, Analgesia, and NeuromuscularBlockade, 235BryanA. Pisk and Lisa K. Moores

Pain, 237Rationale for Pain Management, 237Recognition of Pain, 237Management of Pain, 238

Delirium, 240Recognition of Delirium, 240Treatment of Delirium, 240

Sedation, 241

Rationale for Sedation Management, 241Titration and End Points, 241Drugs Used for Sedation, 242Approach to Management, 243

Neuromuscular Blockade, 245

Drugs Used for NeuromuscularBlockade, 245

Monitoring Use of NMBAs, 247Summary, 248

Chapter 13

Patient Positioning, 252joseph A. Govert

Effects of Posture and Position on HealthyPatients, 253

Lung Volumes, 253Regional Pleural Pressures, 253Regional Lung Inflation, 254Pulmonary Mechanics, 255Distribution of Ventilation, 256Distribution of Perfusion, 256Ventilation-Perfusion (V/Q)

Relationships, 256Effects of Posture and Position

on Patients with RespiratoryDisease, 256

Neuromuscular Disease, 256Obstructive Airway Disease, 257Unilateral Lung Injury, 258Acute Respiratory Distress Syndrome, 258

Chapter 14Ventilator-Associated Pneumonia, 266Mohammed Hijazi and Mariam AI-Ansari

Incidence and Risk Factors, 266Morbidity, Mortality, and Cost, 267Pathogenesis, 268

Colonization, 269

Respiratory Therapy Equipment, 269Host Defenses, 270

Microbiology, 270Diagnosis, 272

Clinical Features and Chest X-Ray, 272Qualitative Culture Techniques, 273Quantitative Culture Techniques, 273

Therapy, 274Empiric Therapy, 274Pharinacologic Consideration, 275De-Escalation and Specific Therapy, 276Duration of Therapy, 276Response to Therapy, 277

Prevention, 277

xvi CONTENTS

SECTION IV

CLlNICAL APPLlCATIONS, 287

Chapter 15

Management of Parenchymal LungInjury, 287

Neil R. MacIntyre

Pathophysiology of Parenchymal LungInjury, 288

Goals of Ventilatory Support, 288Mechanical Ventilation Strategies, 289

Modes Selection, 289

Frequency- Tidal Volume Settings, 290Positive End-Expiratory Pressure and lnspired

Oxygen Concentration, 291Novel Approaches to Lung Protection in

Parenchymal Lung Injury, 292Airway Pressure Release Ventilation,

293

High-Frequency Ventilation, 293Other Considerations in Managing

Parenchymal Lung Injury, 293Outcome of Parenchymal Lung Injury, 293

Chapter 16

Management of Obstructive AirwayDisease, 297

Neil R. MacIntyre

Pathophysiology of Obstructive AirwayDiseases, 297

Goals of Ventilatory Support, 298Mechanical Ventilation Strategies, 298

Mode Selection, 298

Tidal Volume/Frequency /InspiratoryTime, 300

Positive End-Expiratory Pressure/lnspiredOxygen Concentration, 301

Other Considerations in VentilatoryManagement, 302

Outcomes of Respiratory Failure inObstructed Airway Disease, 303

Chapter 17

Unique Patient Populations, 306John H. Shemer and Lisa K. Moores

Traumatic Brain Injury, 307Pathophysiology and Unique Features, 307Management, 307

Neuromuscular Disease, 309Pathophysiology and Unique Features, 309Management, 309

Lung Transplantation, 310Donor Care, 310

Perioperative Care of TransplantRecipients, 311

Buro Injuries, 313Pathophysiology and Unique Features, 313Assessment, 313

Management, 313Perioperative Respiratory Failure, 313

Pathophysiology and Unique Features, 313Management, 313

Conclusions, 314

Chapter 18

Discontinuing Mechanical Ventilation, 317Neíl R. MacIntyre

Considering Ventilator Discontinuation, 318Assessing the Potential for

Discontinuation, 318Next Steps for Patients With Successful

Spontaneous Breathing Trial, 319Managing the Not-Yet-Ready-to-Be

Discontinued Patient, 320The Impact of Newer Feedback

Controllers on Discontinuation, 321Approaches for the Difficult-to- W ean

Patient, 322

Chapter 19Prolonged Mechanical Ventilation, 325Christopher E. Cox and Shannon S. Carson

Prolonged Mechanical Ventilation, 326Epidemiology of PMV, 326

Economics of PMV, 326PMV Patients, 327

Ventilator-Dependent Patients, 327Predicting the Need for PMV, 328

Reducing the Likelihood of PMV, 328Timing for Tracheostomy Placement, 329

Placing a Tracheostomy, 331Outcome of PMV Patients, 331

Disposition, 331Weaning Success, 331Survival, 331

Quality of Life and Functional Status, 331Cost-Effectiveness, 332

Most Effective Way to Wean PMVPatients, 332

Predicting Weaning Success, 333Interventions to Improve PMV

Outcomes, 333

Post-Acute Care Facilities and RespiratoryCare Units in PMV Care, 335

Palliative Care in the PMV Population, 335Summary,336

CONTENTS xvii

Chapter 20Mechanical Ventilation DuringTransport and CardiopulmonaryResuscitation, 339Richard D. Branson and Jay A. Johannigman

Ventilation During CardiopulmonaryResuscitation, 340

Standards for Ventilation and Devices, 340Lung Compliance After Cardiac Arrest, 340

Techniques of EmergencyVentilation, 341

Expired Air Resuscitation, 341Cricoid Pressure, 342Disease Transmission, 342Barrier Devices, 343Mouth-to-Mask, 344

Bag-Valve Devices, 346Description, 346Bag-Valve Device Performance, 347Ventilation Efficacy, 347Delivered Oxygen Concentration, 348Nonrebreathing Valve Performance, 348

Oxygen-Powered Breathing Devices, 349Description, 349Assessment, 350Ventilator-to-Mask Ventilation, 350

Impedence Threshold Device, 352

Transport of the Mechanically VentilatedPatient, 352

Rationale for Transport, 352Preparation, 352Equipment, 353Characteristics of a Ventilator for lntrahospital

Transport, 354Physiologic Effects and Risks of

Transport, 357

Chapter 21Noninvasive MechanicalVentilation,366Nicholas S. Hill

Rationale for the Use of Noninvasive

Ventilation, 367Indications for Noninvasive Ventilation:

Acute Applications, 367Best Established lndications, 367

Indications Supported by WeakerEvidence, 369

Other Obstructive Diseases, 369Extubation Failure, 369

Postoperative Respiratory Failure/lnsufficiency, 370

Do Not Intubate Status, 370

Other Acute Applications of NoninvasiveVentilation, 370

Selection Guidelines for Noninvasive

Ventilation in Acute RespiratoryFailure, 370

Determinants of Success/Failure, 370Selection Process, 371

Long- Term Applications of NoninvasiveVentilation, 372

Restrictive Thoracic Disease, 372

Chronic Obstructive Pulmonary Disease, 372Obesity Hypoventilation, 373Selection Guidelines, 373

Contraindication to Long- TermNoninvasive Ventilation, 373

Techniques and Equipment forNoninvasive Ventilation, 374

N oninvasive Positive- Pressure

Ventilation, 374Interfaces, 375Ventilators for Positive-Pressure Noninvasive

Ventilation, 378Application of Noninvasive Positive-

Pressure Ventilation, 381Initiation, 381General Considerations, 382

Adaptation and Monitoring, 383Long- Term Applications, 383Common Problems and Possible

Remedies, 384

Summary and Conclusions, 386

Chapter 22Modifications on ConventionalVentilation Techniques,392

John D. Davies

Airway Pressure Release Ventilation, 393Description and Rationale, 393Clinical Data, 394Recommendations, 394

Independent Lung Ventilation, 394Description and Rationale, 394Clinical Data, 397Recommendations, 397

Proportional Assist Ventilation, 397Description and Rationale, 397Clinical Data, 398Recommendations, 400

Tracheal Gas Insufilation, 400

Description and Rationale, 400Clinical Data, 401Recommendations, 401

xviii CONTENTS

Modifications for Nuclear MagneticScanners and HyperbaricCharnbers, 402

MRI-Compatible Equipment, 402Hyperbaric Chamber-Compatible

Equipment, 402

Chapter 23

High-Frequency Ventilatian, 407

Michael A. Gentile and Neil R. MacIntyre

Devices, 408Jets, 408Oscillators, 410

Mechanisrn of Gas Transport, 411Applications, 412Cornplications, 414Surnrnary, 414

Chapter 24Extracarpareal Techniques far

Cardiapulmanary Suppart, 418Michael A. Gentile and Ira M. Cheifetz

History of Extracorporeal Life Support,418

Patient Selection and Criteria for

Extracorporeal Life Support, 419Types of Extracorporeal Life Support, 421

Venoarterial Extracorporeal Life Support, 421Venovenous Extracorporeal Life Support, 422

Cornplications Associated WithExtracorporeal Life Support, 423

Patient Managernent DuringExtracorporeal Life Support, 423

Ventilator and Respiratory Care, 423

Anticoagulation, 424Sedation and Analgesia, 424Nutrition, 424

Current Status of ExtracorporealLife Support and Outcorne inPediatrics, 424

Extracorporeal Life Support Technologyfor Adult Respiratory Failure, 424

Surnrnary, 426

Chapter 25Heliax and Inhaled Nitric Oxide, 429Dean R. Hess

Heliox, 429

Physics and Physiology, 429Clinical Applications, 431Oelivery Systems for Heliox, 435

Inhaled Nitric Oxide, 437

Biology of Nitric Oxide, 437Selective Pulmonary Vasodilation, 438Clinical Applications, 439Toxicity and Complications of Inhaled Nitric

Oxide, 439

Oelivery Systems for lnhaled NitricOxide, 440

Appendix 1Mechanical Ventilatian Case Studies, 451Neil R. MacIntyre

Appendix 2Assessment Questian Answers, 467

Glossary, 473