Most Patients Enrolled in Pulmonary Rehabilitation Have COPD
Exercise Capacity in Patients with Chronic Respiratory Disease (Such as COPD) is Impaired and Frequently Limited by Dyspnea
Factors Contributing to Exertional Dyspnea During Exercise in COPD
Defective Gas Exchange
Dynamic Hyperinflation
Increased Respiratory Load
Peripheral Muscle Dysfunction
Factors Contributing to Exercise Limitation in COPD
Ventilatory Limitation
In COPD, Ventilatory Requirements are Higher than Expected Due to the Presence of Increased Work of Breathing, Increased Dead Space Ventilation, Impaired Gas Exchange, Increased Ventilatory Demand Due to Deconditioning and Peripheral Muscle Dysfunction
Expiratory Airflow Obstruction with Dynamic Hyperinflation Limit Maximal Ventilation During Exercise: this leads to further increase in the work of breathing, increased respiratory muscle load, and increased mechanical constraint on the respiratory muscles
Gas Exchange Limitation
Hypoxia Directly Increases Pulmonary Ventilation Via Peripheral Chemoreceptors and Indirectly Via the Development of Lactic Acidosis
Supplemental Oxygen During Exercise Decreases Pulmonary Artery Pressure, Decreases Carotid Body Inhibition, Decreases Lactic Acidosis: this decreases the respiratory rate, with resulting decreased dynamic hyperinflation
Cardiac Limitation
Hypoxic Pulmonary Vasoconstriction, Hypoxic Pulmonary Vascular Remodeling and/or Injury, and Polycythemia-Induced Increase in Pulmonary Vascular Resistance Lead to Increased Right Ventricular Afterload
Air Trapping Elevates Right Atrial Pressure: elevated right atrial pressure may compromise cardiac function during exercise
Limitation Due to Lower Limb Muscle Dysfunction: commonly present in patients with chronic lung disease
Limitation Due to Respiratory Muscle Dysfunction
Although the Diaphragm in COPD Adapts to Chronic Overload and Has a Greater Resistance to Fatigue, Patients Often Have Static and Dynamic Hyperinflation (Putting Their Respiratory Muscles at a Mechanical Disadvantage): therefore, both functional inspiratory muscle strength and inspiratory muscle endurance are impaired in COPD (and respiratory muscle weakness is often present)
Exercise Training is the Best Available Means of Improving Muscle Function in COPD
Even Patients with Severe Lung Disease Can Often Sustain the Necessary Training Intensity and Duration for Skeletal Muscle Adaptation to Occur
Improvements in Skeletal Muscle Function After Exercise Training Result in Gains in Exercise Capacity Despite the Absence of Changes in Intrinsic Lung Function
Improved Oxidative Capacity and Efficiency of Skeletal Muscles Leads to Decreased Ventilatory Requirements for a Given Submaximal Work Rate: this may result in decreased dynamic hyperinflation (with a decrease in the degree of exertional dyspnea)
Exercise Training May Also Increase Motivation for Exercise Outside of the Rehabilitation Setting, Decrease Modd Disturbance, Decrease Symptom Burden, and Improve Cardiovascular Function
Clinical Efficacy-General
Pulmonary Rehabilitation Decreases Dyspnea, Decreases Health Care Utilization, Improves Quality of Life, and Increases Exercise Capacity in COPD
Patients with Lesser Degrees of Airflow Obstruction Derive Improvements from Pulmonary Rehabilitation than Patients with More Severe Airflow Obstruction
Pulmonary Rehabilitation Initiated Shortly After a Hospitalization for a COPD Exacerbation is Clinically Effective, Safe, and Associated with a Decreased Risk of Subsequent Hospital Admission
Pulmonary Rehabilitation Initiated During Acute or Critical Illness Decreases the Extent of Functional Decline and Hastens Recovery
Anxiety and Depression are Prevalent in Patients Referred to Pulmonary Rehabilitation, May Affect Outcomes, and Can be Ameliorated by Pulmonary Rehabilitation
Clinical Efficacy-Site of Pulmonary Rehabilitation
Meta-Analysis of Efficacy of Pulmonary Rehabilitation in Different Settings (J Clin Nurs, 2007) [MEDLINE]
Efficacy of Pulmonary Rehabilitation is Not Influenced by FEV1, Duration and Frequency of the Rehab, Whether Program was Lower Extremity Only Training vs Combined Upper and Lower Extremity Training, or Exercise Intensity
Efficacy of Pulmonary Rehabilitation is Not Influenced by Hopsital-Based vs Community-Based Program
Randomized Trial of Home-Based vs Outpatient-Based Pulmonary Rehabilitation in COPD (Ann Intern Med, 2008) [MEDLINE]
Home Pulmonary Rehabilitation is Equivalent to Outpatient-Based Pulmonary Rehabilitation: both produced similar improvements in dyspnea at 1 year
Most Adverse Events Were Related to COPD Exacerbations: no serious events were related to the study intervention
Clinical Efficacy-Prevention of Hospitalization for COPD Exacerbation
Systematic Review and Meta-Analysis of Pulmonary Rehab in the Prevention of Hospitalization for COPD Exacerbation (Chest, 2016) [MEDLINE]; n = 18 studies
Pulmonary Rehab Did Not Decrease the Rate of Hospitalization for COPD Exacerbation: likely due to the heterogeneous nature of patients included in observational studies and the varying standard of pulmonary rehab programs
Recommendation (American College of Chest Physicians/Canadian Thoracic Society Guidelines on the Prevention of COPD Exacerbations, 2015) (Chest, 2015) [MEDLINE]
In Moderate-Very Severe COPD with a Recent Exacerbation (Within 4 wks), Pulmonary Rehabilitation is Recommended to Decrease the COPD Exacerbation Rate (Grade 1C Recommendation)
In Moderate-Very Severe COPD with an Exacerbation >4 wks Ago, Pulmonary Rehabilitation is Not Recommended to Decrease the COPD Exacerbation Rate (Grade 2B Recommendation)
Cystic Fibrosis (CF) (see Cystic Fibrosis, [[Cystic Fibrosis]])
Usually Recommended to Assess for Exercise-Associated Hypoxemia, Arrhythmias, Musculoskeletal Problems, and Myocardial Ischemia Prior to the Start of Pulmonary Rehabilitation
Site of Pulmonary Rehabilitation
Hospital-Based
Outpatient-Based
Home-Based
References
Meta-analysis of the effects of respiratory rehabilitation programmes on exercise capacity in accordance with programme characteristics. J Clin Nurs. 2007 Jan;16(1):3-15 [MEDLINE]
Effects of home-based pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: a randomized trial. Ann Intern Med. 2008 Dec 16;149(12):869-78 [MEDLINE]
Optimizing pulmonary rehabilitation in chronic obstructive pulmonary disease–practical issues: a Canadian Thoracic Society Clinical Practice Guideline. Can Respir J. 2010 Jul-Aug;17(4):159-68 [MEDLINE]
An official American Thoracic Society/European Respiratory Society statement: key concepts and advances in pulmonary rehabilitation. Am J Respir Crit Care Med. 2013 Oct 15;188(8):e13-64. doi: 10.1164/rccm.201309-1634ST [MEDLINE]
Effects of inpatient pulmonary rehabilitation in patients with interstitial lung disease. Eur Respir J 2013; 42:444–453 [MEDLINE]
Prevention of acute exacerbations of COPD: American College of Chest Physicians and Canadian Thoracic Society Guideline. Chest. 2015 Apr;147(4):894-942. doi: 10.1378/chest.14-1676 [MEDLINE]
Pulmonary Rehabilitation as a Mechanism to Reduce Hospitalizations for Acute Exacerbations of COPD: A Systematic Review and Meta-Analysis. Chest. 2016 Oct;150(4):837-859. doi: 10.1016/j.chest.2016.05.038. Epub 2016 Aug 3 [MEDLINE]
