This new edition presents an evidence-based review of extracorporeal membrane oxygenation (ECMO) for adults, with a particular focus on veno-venous (VV) ECMO. Due to the dramatic impact of COVID-19, the number of institutions offering ECMO, thus the number of clinicians performing ECMO (or referring their patients for ECMO), has exploded in a truly unprecedented way. While the pandemic may fade, programs built in response will survive by extending the application of ECMO to previously overlooked populations.
This fully updated second edition refines its focus to VV ECMO, which has seen the most dramatic increase and relevance. This allows expert authors to go further in depth regarding VV ECMO and provide readers with better guidance from the physiology of VV ECMO to weaning and decannulation. Several areas have been expanded, including anti-thrombotic approaches; how to set the mechanical ventilator and judge the complex interactions between patient, ventilator, and ECMO circuit; assessing the systemic circulation during VV ECMO (especially right ventricular function and intravascular volume); and recognizing membrane lung dysfunction. Finally, new chapters addressing how the VV-capable clinician should think about VA ECMO and how to incorporate ethical principles in patient selection and withdrawal of ECMO have been added.
This is an ideal guide for intensive care and respiratory medicine specialists, fellows training in critical care, ECMO specialist staff, perfusionists, nurses, and respiratory therapists.
Author(s): Gregory A. Schmidt
Series: Respiratory Medicine
Edition: 2
Publisher: Humana
Year: 2022
Language: English
Pages: 313
City: New York
Preface to the 2nd Edition
Contents
Contributors
Chapter 1: Physiology of Extracorporeal Life Support (ECLS)
Introduction
Cellular Metabolism
Glycolysis and Aerobic and Anaerobic Metabolism
Carbon Dioxide Production and the Respiratory Quotient
Metabolism in the Stressed State
Erythrocyte Metabolism
Biophysics of Membrane Gas Exchange
Membrane Oxygenator Construction
Diffusion of Gas Molecules into a Liquid Phase
Concentration of Gases in Solutions
The Solubility of Respiratory Gases in Solution
Biophysics of Membrane Oxygenation
The Driving Force for Diffusive Transport of Gases
Membrane Exposure Time
Relative Flow Direction
Effect of Turbulence and Haematocrit on Local Concentration Gradients
Resistances to Diffusive Transport
Area of the Gas Exchange Membrane
Ultrafiltration of Plasma Water Over the Oxygenator Membrane [16]
Membrane Oxygen Flux Matches Demand
Oxygen Transport
Oxygen Carriage
Modulation of Haemoglobins Affinity for Oxygen
The Oxygen-Haemoglobin Dissociation Curve
Mixing Blood of Differing Oxygen Partial Pressures
Venovenous ECMO and Oxygen Transport
Arterial Saturations Are Dependent on the Fraction of Cardiac Output Captured
Mixed-Venous Saturations Are Determined by VO2 and Cardiac Output
The Effect of Oxygen-Carrying Capacity
Modelling VV-ECMO
Further Consideration of Recirculation
The Importance of Mixed-Venous Saturation
Venous Oxyhaemoglobin Saturation
Carbon Dioxide Physiology
Carbon Dioxide Transport in Physical Solution
Reactions of Carbon Dioxide in Solution
Effect of the Hydrogen Ion Concentration
Carbonic Anhydrase
The Arteriovenous-CO2 Difference and Carbamino Carriage
Determinates of Carbon Dioxide Partial Pressure
Extracorporeal Carbon Dioxide Removal (ECCO2R)
Blood Flow Requirements of ECCO2R
Recirculation with Smaller Access Catheters
Oxygenation in ECCO2-R: Integration with Pulmonary Oxygenation
Ventilation Strategies with ECCO2-R
Passive Oxygenation and Low Tidal Volume Strategies
ECCO2-R and Alveolar Oxygen Concentrations
Biophysics of the Extracorporeal Blood Path
Types of Blood Pump
Positive Displacement Pumps
Velocity Pumps
Centrifugal Constrained Vortex Pumps
Axial Flow Pumps
Monitoring Pump Output
Physical Properties of Blood Relevant to Flow
Viscoelasticity
Flow of Ideal Fluids in Solid Conduits
Resistance to Flow
Resistance to Laminar Flow
Turbulent Flow
Reynolds Number
Optimising Blood Flow for Gas Transfer
The Oxygenator as a Resistor
Conservation of Energy Across the ECMO Circuit
Occlusion of the Flow Path
Flow Regurgitation
Cavitation
Interaction of Velocity Pumps with the Systemic Circulation
Adequacy of Cardiac Output
Right Ventricular (RV) Function and Pulmonary Haemodynamics
Thrombus Formation and Anticoagulation
Reparative Properties of the Lung
Conclusions
References
Chapter 2: Circuits, Membranes, and Pumps
Introduction
Circuit Anatomy
Overall Circuit Considerations
Circuit Priming
Orientation to the Circuit
Function of the Circuit Components
Cannulas and Tubing
Centrifugal Pumps
Membrane Oxygenators
Additional Limitations of Membrane Oxygenators
Renal Replacement Therapy
Circuit Surface Coatings
Heat Exchanger and Heater-Cooler
Conclusions
References
Chapter 3: Modes of ECMO
Chapter 3 Modes
Nomenclature
Veno-venous ECMO (VV-ECMO)
The VV Circuit
Physiological Implications of VV ECMO
Advantages of VV ECMO
Veno-arterial ECMO
The VA Circuit
Physiological Implications of VA ECMO
Advantages of VA ECMO
Hybrid ECMO Configurations
VVA-ECMO
Extracorporeal CO2 Removal Modes
VV ECCO2R
AV ECCO2R
CVVRRT
References
Chapter 4: Vascular Access
Introduction
Cannulas for Extracorporeal Support
Single-Lumen Design
Dual-Lumen Design
Determinants of Cannula Blood Flow
Patient Preparation
Determination of Vessel Size
Infection Control
Insertion Technique
Percutaneous
Semi-Open
Open Surgical
Cannulation Configuration
Venoarterial (VA) Configuration
Venovenous (VV) Configuration
Venopulmonary (VP) Configuration
Venovenoarterial (VVA) Configuration
Low-Flow Venovenous Configuration
Arteriovenous (AV) Configuration
Transthoracic (Central) Cannulation
Decannulation
Complications of Cannulation
Vascular Injury
Inadequate Flow
Limb Ischemia
Insertion Site Bleeding
Recirculation
Infectious Complications
References
Chapter 5: Hypoxemic Respiratory Failure: Evidence, Indications, and Exclusions
Evidence
Indications
Exclusions
Conclusion
References
Chapter 6: Ventilator Management During ECLS
Introduction
Pathophysiology of Gas Exchange During ECLS
Oxygenation
Carbon Dioxide
The Acute ARDS Phase: Controlled Mechanical Ventilation
Walking the Tightrope Between Lung Recruitment and Lung Rest
Rescue Treatments for Persistent Hypoxemia During ECLS
Prone Positioning
Inhaled Pulmonary Vasodilators
High-Frequency Oscillatory Ventilation (HFOV)
Management of Pneumothoraces
Assisted Ventilation During ECLS
Avoiding Intubation by ECMO: Is It Possible?
Monitoring Respiratory Effort in Spontaneously Breathing Patients on ECLS
Disconnection from ECLS
Partial Extracorporeal CO2 Removal (PECOR) and Ventilator Management
Conclusions
References
Chapter 7: Managing the Systemic Circulation: Volume Status and RV Function
Volume Status
Monitoring
Management
Right Ventricular Function
Monitoring
Management
Conclusion
References
Chapter 8: Antithrombotic Therapy for ECMO
Introduction
Hemostatic Alterations During ECMO
Hematologic Consequences with ECMO
Inflammatory Consequences with ECMO
Anticoagulation
Role of Hemostatic Adjuncts
Monitoring of Anticoagulation
Specific Situations
Conclusion
References
Chapter 9: Membrane Dysfunction
Introduction
Mechanisms of Membrane Lung Dysfunction
Membrane Lung Monitoring
Hematologic Profile
Circuit Pressure Monitoring
ML Gas Transfer
ML Shunt Fraction
ML Dysfunction
Hematologic Abnormalities
Obstruction to Blood Flow
Inadequate Oxygen Uptake
Inadequate Carbon Dioxide Clearance
Exchanging the ML
References
Chapter 10: ECCO2R in Obstructive Diseases: Evidence, Indications, and Exclusions
Introduction
Evidence
Indications
Exacerbation of Chronic Obstructive Pulmonary Disease (COPD)
Acute Severe Asthma
Exclusions
References
Chapter 11: ECMO as a Bridge to Lung Transplantation
Introduction
Historical Aspects
Modes of Support
Interventional Lung Assist
Veno-venous ECMO
Venoarterial ECMO
Complex Forms of Support
ECLS as a Bridge to Transplantation: General Considerations
Pulmonary Failure
Pulmonary Hypertension and Right Ventricular Failure
Patient Transport While on ECLS
Preventing Mechanical Ventilation with ECLS
Other Indications for ECLS in Lung Transplantation
Intraoperative VA-ECMO
Postoperative ELCS
ECLS for Organ Preservation
Conclusions
References
Chapter 12: Daily Management of Patients on VV ECMO
The Daily Survey
Gas Exchange
Ancillary Therapies
Antithrombotic Therapy
Renal Replacement Therapy
Prone Position and Mobilization
Necessity of Lines and Tubes
Assessing Other Systems
Hemodynamics
Neurological Function
Circuit Evaluation and Safety
Goals of Therapy
References
Chapter 13: Crises During ECLS
Introduction
Circuit Crises
Emergency Management During Circuit Clamping
Circuit Air
Thrombosis
Oxygenator Failure
Pump Failure
Tubing Rupture/Disconnect/Cannula Fracture
Heat Exchanger
Inadvertent Decannulation
Patient Crises
Bleeding and Transfusions
Hemolysis
Refractory Hypoxemia
Shock
Limb Ischemia
Conclusion
References
Chapter 14: Mobilization During ECLS
Technological Advances
The Health Costs of Immobility
Early Mobilization Promotes Recovery
Mobilization During ECLS
Barriers to Mobilization During ECLS
Mobilization: Team and Methods
Conclusion
References
Chapter 15: ECMO Weaning and Decannulation
Introduction
Weaning from VV ECMO
Signs of Readiness
ECMO Weaning and Liberation
Ventilator Management
Oxygenator Sweep Gas Flow Management
Separate Deoxy and Carboxy Challenge
Simultaneous Deoxy and Carboxy Challenge
ECMO Flow Management
Sedation Management
Hemodynamic Management
Anticoagulation Management
Decannulation
Following Decannulation
Extubation Prior to Decannulation
Weaning from VA ECMO
Termination of ECLS in Those Who Do Not Recover
References
Chapter 16: Venoarterial ECMO in Respiratory Failure
Introduction
Fundamentals of VA ECMO
Anatomy
Equipment
Monitoring
Adequacy of Oxygenation via the ECMO Circuit
Adequacy of Overall Gas Exchange (ECMO and Native Circulation)
Adequacy of Upper Body Oxygenation
Distal Limb Ischemia
Weaning
Clinical Indications for VA ECMO for Respiratory Failure
Vasoplegic Shock
Respiratory Failure with Cardiogenic Shock
Patients with Inadequate Oxygenation Despite Maximal VV ECMO Support
Conclusion
References
Chapter 17: Ethical Challenges in Extracorporeal Membrane Oxygenation
Introduction
Initiating ECMO
Continuing ECMO
Terminating ECMO
Ethics Consultation
Health Disparities
Scarce Resource Allocation
Integrating Ethics into Education
References
Index
