Chapter 12: Chronic Pulmonary Dysfunction

Pulmonary rehabilitation is a multidisciplinary comprehensive program of care for patients with chronic respiratory disease that is designed to reduce symptoms, optimize physical functioning and social participation, and reduce health care costs.¹ A diversity of health professionals is essential to meet the medical, physical, social, and psychological needs of the patient with pulmonary disease. The team may include a nurse, physician, physical therapist, occupational therapist, nutritionist, pharmacist, respiratory care practitioner, exercise physiologist, psychologist, and, most important, the patient and the patient's family and caregivers.

Years ago, patients with chronic pulmonary disease were given a standard prescription for rest and avoidance of exercise.² The stress imposed by exercise was considered deleterious to people with pulmonary disorders. A pivotal study by Pierce et al³ provided the impetus to change direction in the treatment of pulmonary dysfunction. Exercise training effects of decreased heart rate (HR), respiratory rate, minute ventilation, oxygen consumption, and carbon dioxide production at submaximal exercise levels were documented in their subjects with chronic obstructive pulmonary disease (COPD). Increased maximal aerobic capacity was also documented.³ Reconditioning of patients with pulmonary disease was found to be possible.

COPD, asthma, and cystic fibrosis are the most common chronic obstructive lung diseases for which pulmonary rehabilitation is rendered. Patients with a restrictive lung disease, such as idiopathic pulmonary fibrosis, have also demonstrated improvement in functional abilities following pulmonary rehabilitation.⁴ It is clear that pulmonary rehabilitation is of value for all patients in whom respiratory symptoms have resulted in a decreased functional capacity or a decreased quality of life.¹

In this chapter, the most common chronic pulmonary diseases that present to pulmonary rehabilitation programs will be discussed, as well as the physical therapy examination and treatment of patients with chronic pulmonary disease. A brief review of ventilation and respiration is warranted for a better understanding of the disease pathologies and for understanding the rationale of the physical therapy procedures.

Air is inspired through the nose or mouth, through all of the conducting airways until it reaches the distal respiratory unit, which contains the respiratory bronchiole, alveolar ducts, alveolar sacs, and alveoli (Fig. 12.1). The movement of air through the conducting airways is termed ventilation. At full inspiration, the lungs contain their maximum amount of air. This volume of air is called total lung capacity (TLC), which can be divided into four separate volumes of air: (1) tidal volume, (2) inspiratory reserve volume, (3) expiratory reserve volume, and (4) residual volume. Combinations of two or more of these lung volumes are termed capacities. Figure 12.2 illustrates the relationship of lung volumes and capacities.

The amount of air inspired or expired during normal resting ventilation is termed tidal volume (TV or V_t). As this tidal volume of air enters the respiratory system, it travels through the conducting airways to reach the respiratory units. Tidal volume is about 500 mL/breath for a young, healthy, white male. The amount of inspired air that actually reaches the distal respiratory unit and takes part in gas exchange is about 350 mL of that 500 mL total of the tidal breath. The remaining 150 mL of the inhaled tidal breath remains in the conducting airways and does not take part in gas exchange. When only a tidal breath occupies the lungs, there is "room" for additional air that can be further inhaled. This inspiratory volume in excess of that used in tidal breathing is the inspiratory reserve volume (IRV). Aptly named, it is the volume of air that can be inspired when needed, but is usually kept in reserve. There is a quantity of air that can potentially be exhaled beyond the end of a tidal exhalation. Although it is usually kept in reserve, the volume of air that can be exhaled in excess of tidal breathing is called the expiratory reserve volume (ERV). The lungs are never completely emptied of air even after maximally exhaling the expiratory reserve volume. The volume of air remaining within the lungs when ERV has been exhaled is called the residual volume (RV).

The sum of two or more volumes is referred to as a capacity. Tidal volume plus the inspiratory reserve volume is known as the inspiratory capacity (IC). This refers to the volume of air that can be inspired beginning from a tidal exhalation. The combination of residual volume and expiratory reserve volume is the functional residual capacity (FRC). Functional residual capacity is the volume of air that remains in the lungs at the end of a tidal exhalation. The sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume is called the vital capacity (VC). It is all of the possible volume of air within the lungs that is under volitional control. The common method of measuring VC is to achieve maximal inspiration, then forcibly exhale as hard and fast as possible into a measuring device until ERV has been exhausted. Because this is a forced expiratory maneuver, it is termed the forced vital capacity (FVC). As stated earlier, all volumes together equal total lung capacity:

Flow rates measure the volume of air moved in a period of time. Expiratory flow rates, therefore, are measurements of exhaled gas volume divided by the amount of time required for the volume to be exhaled. Flow rates reflect the ease with which the lungs can be ventilated, the state of the airways, and the elasticity of the lung parenchyma (tissue). An important airflow measurement is the volume of air that can be forcefully exhaled during the first second of a forced vital capacity maneuver. This is called the forced expiratory volume in 1 second (FEV₁). This flow rate is thought to reflect the status of the airways of the lungs. In healthy individuals, FEV₁ is 70% or more of the total FVC (FEV₁/FVC > 70%).⁵ Peak expiratory flow rate (PEF) is the greatest flow rate generated during a maximal forced expiratory maneuver. Individuals with lung disease often measure PEF on a daily basis with a handheld peak flow meter to track their pulmonary status. Daily peak flow rates are compared to the patient's own "best" test value.⁶ A drop in a patient's peak flow rate indicates airway narrowing and may indicate the need for a physician visit and/or change in medication regimen.

Inspiratory mechanics can be helpful in understanding a patient's pulmonary disease. Maximum inspiratory pressure (PI_max) reflects the greatest static inspiratory effort that can be generated from residual volume. It is measured as a pressure in millimeters of mercury or cubic centimeters of water and reflects the strength of the muscles of inspiration. Maximal sustained inspiratory pressure (SIP_max) is a test of inspiratory muscle endurance. The patient is initially challenged with −6 cm H₂O pressure resistance. Gradually the resistance is increased −2 cm H₂O every 2 minutes until the patient can no longer achieve adequate ventilatory flow levels.⁷ The maximal pressure is defined as the highest level that the patient could tolerate during the testing procedure.

Lung volumes, capacities, flow rates, and mechanics depend on the size and configuration of the thorax. Therefore, height, gender, and race influence static and dynamic lung measurements. Any alteration in the properties of the lungs or chest wall due to the aging process or a disease process will also change the lung volumes, capacities, flow rates, and/or mechanics.

Respiration is a term used to describe the gas exchange within the body. This should not be confused with ventilation, which describes only the movement of air. External respiration is the exchange of gas that occurs at the alveolar capillary membrane between atmospheric air and the pulmonary capillaries. Internal respiration takes place at the tissue capillary level between the tissues and the surrounding capillaries. The following discussion traces the course of gas exchange, specifically that of oxygen and carbon dioxide, during both external and internal respiration (Fig. 12.3).

For external respiration to take place, there must first be an inhalation of air from the environment, through the conducting airways, and into the respiratory bronchioles and alveoli. Oxygen diffuses through the walls of the respiratory unit, through the interstitial space, and through the pulmonary capillary wall. Most of the oxygen (98.5%) then travels through the blood plasma into red blood cells where it occupies one of the gas-carrying sites of hemoglobin. A small portion of dissolved oxygen (1.5%) is carried in the plasma.

The now oxygenated blood in the pulmonary capillaries travels to the left side of the heart via the pulmonary veins. From there it is pumped into the aorta, and then through a network of connecting arteries, arterioles, and capillaries, until its destination, the tissue, is reached. Internal respiration begins when the arterial blood reaches the tissue level. Oxygen diffuses from the gas-carrying sites of hemoglobin, out of the red blood cell, out of the capillary, through the cell membranes, and into the mitochondria of the working cells.

Carbon dioxide (CO₂), which is produced at the tissue level as a by-product of metabolism, diffuses out of the working cells into the capillaries. Carbon dioxide is transported in the blood through the venous system into the right side of the heart. Once the carbon dioxide– ladened blood makes its way through the right atrium, the right ventricle, the pulmonary artery, and the pulmonary capillaries, it diffuses out through the capillary membrane, through the interstitial space, and into the alveoli, where it is finally exhaled into the atmosphere.

When the cycle of external and internal respiration has occurred, oxygen has been extracted from the environment and provided to the body tissues. Meanwhile, carbon dioxide has been removed from the body tissues and released into the external environment. Of course, this system is dependent on an intact cardiovascular system to pump the blood through the lungs and through the heart, deliver it to the working cells, and then return it back to the lungs, all in a timely fashion.

Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is the most common chronic pulmonary disorder. It is the fourth-leading cause of morbidity and mortality in the United States.⁵

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) is an ongoing collaborative work of the National Heart, Lung, and Blood Institute (NHLBI) and the World Health Organization (WHO). Initially begun in 2001, GOLD set out to increase worldwide awareness of COPD, to advocate for its prevention as well as to decrease morbidity and mortality from the disease. According to GOLD, COPD is defined as a preventable and treatable disease. The pulmonary component of COPD is characterized by airflow limitation that is not fully reversible. The airflow limitation is usually progressive and associated with an abnormal inflammatory response of the lung to noxious particles or gases. Additional significant extra pulmonary effects, such as a decrease in body mass index (BMI) and exercise tolerance, contribute to the severity of COPD in individual patients.⁵ Classification of disease severity is based on both clinical symptoms and measurements of airflow limitation. Table 12.1 shows the GOLD COPD classification of disease severity based on a patient's altered FEV₁ and presenting symptoms.

Risk Factors

Risk factors for the development of COPD include both environmental factors and host factors. Cigarette smoking is the major environmental causal agent in the development of COPD.⁵ Smoking history is quantified in units of pack/years, the number of packs per day times the number of years smoked. Other environmental factors that contribute to the development of COPD include occupational exposures (e.g., organic and inorganic dusts), indoor pollutants (e.g., secondhand smoke), and outdoor pollutants (e.g., urban pollution).⁵

Host factors that would make a person more susceptible to the development of COPD include hyperreactivity of the airways, overall lung growth (the amount of lung tissue developed during childhood, which is dependent on the person's nutritional status, health status, height, exposure to pollutants, and so forth), and genetics. One genetic cause of COPD is an alpha-1 antitrypsin deficiency.⁸ It is perplexing that not all smokers go on to develop clinically significant COPD. The COPDGene^® Study is investigating the potential for a genetic influence that would help explain the development of COPD in only a portion of smokers while others, who may exhibit similar airway inflammation from cigarette smoke, do not develop the disease.⁹ At this point, it would appear that the development of COPD results from a combination of both host and environmental factors.

Pathophysiology

COPD is a combination of chronic airway inflammation and remodeling (reorganization of tissue during healing) that results in airway narrowing, parenchymal destruction, and pulmonary vascular thickening. Chronic inflammation, characterized by an increase in neutrophils, macrophages, and T lymphocytes, damages the endothelial lining of the airways. Airway inflammation is made worse by an imbalance of proteases/antiproteases and oxidants/antioxidants in patients with COPD.⁵ Airway damage results in airway repair, leading to airway remodeling. These airway changes appear to be most pronounced in the smaller peripheral airways (bronchioles).⁵ The glands and goblet cells within the bronchial walls hypertrophy producing excessive secretions, which either partially or completely obstruct the airways. Decreases in ciliary function and alterations in physiochemical characteristics of bronchial secretions impair airway clearance and contribute to airway obstruction. Damaged and inflamed mucosa shows an increased sensitivity of irritant receptors within the bronchial walls, which in turn cause bronchial hyperreactivity.

During normal inspiration, the lungs and the airways are pulled open, increasing the diameter of the airway lumen. During normal exhalation, as the thorax returns to its resting position, the airways decrease in size. In COPD, during inspiration, the airways are pulled open wide by thoracic expansion, allowing air to enter. During exhalation, the airways, already narrowed by inflammation, remodeling, and excessive secretions, are prematurely closed, trapping air in the distal airways and airspaces. This air trapping causes hyperinflation, which is defined as an abnormal increase in the amount of air within the lung tissue at the end of a tidal exhalation (increased FRC).

The most common parenchymal changes found in COPD are dilation and destruction of the airspaces, which is thought to be due to an imbalance of proteases and antiproteases in the lung.⁵ This change results in loss of the normal elastic recoil properties of the lung tissue. The pulmonary vasculature is also altered early in the development of COPD. Endothelial changes result in thickening of the vessel walls. In advanced stages of the disease, there is destruction of the pulmonary capillary bed.⁵

Ventilation in the alveoli and perfusion in the capillary membrane are no longer matched. This results in hypoxemia, a condition in which a decreased amount of oxygen is carried by the arterial blood to the tissues. As the disease progresses and more areas of the lungs become involved, hypoxemia will worsen and hypercapnea, a condition in which there is an increased amount of carbon dioxide within the arterial blood, will develop. Increased pulmonary vascular resistance secondary to capillary wall damage and reflex vasoconstriction in the presence of hypoxemia results in right ventricular hypertrophy, termed cor pulmonale. Polycythemia, an increase in the amount of circulating red blood cells, is another complication of advanced COPD.

Clinical Presentation

Patients with COPD will usually present with a history of cigarette smoking and symptoms of chronic cough, expectoration, and exertional dyspnea. The intensity of each symptom varies from patient to patient. Cough and expectoration appear slowly and insidiously. Dyspnea is first evidenced during exertion. As the disease progresses, symptoms worsen. Dyspnea occurs at progressively lower activity levels. Severely involved patients may feel dyspneic even at rest. On physical examination, the thorax appears enlarged owing to loss of lung elastic recoil and hyperinflation. The anterior-posterior diameter of the chest increases and a dorsal kyphosis results. These anatomical changes give the patient a barrel-chest appearance (Fig. 12.4).

As the resting position of the thorax is now held in a more inspiratory mode, the available range of thoracic motion is limited, that is, decreased thoracic excursion. There are morphologic changes to the ventilatory muscles due to a greater demand, both in frequency and in power needed for this altered thorax. The muscles of ventilation hypertrophy as a result. Figure 12.5 shows many of the accessory muscles of ventilation that may be recruited for breathing. In severe disease, these muscles are recruited even at rest to aid in the work of breathing. The length–tension relationship of muscles of ventilation is altered as the thorax increases in size with chronic hyperinflation. There are changes in the alignment of fibers, especially the fibers of the diaphragm, with hyperinflation. The diaphragm becomes flatter, or less domed. In severe disease, the diaphragm fiber alignment may become more horizontal than vertical, resulting in an inward motion of the lower ribs during a diaphragm muscle contraction of inhalation (Fig. 12.6).

Breath sounds and heart sounds may be distant and difficult to hear. Partially obstructed bronchi and bronchioles may result in an expiratory wheeze, a musical, whistling sound. Crackles, an intermittent bubbling or popping sound, may also be present from secretions in the airways. Hypertrophy of accessory muscles of ventilation, pursed-lip breathing, cyanosis, and digital clubbing may all be present in the advanced stages of COPD. (See Examination in section titled Physical Therapy Management for clarification of terms.)

Significant and progressive airway limitation is reflected in altered pulmonary function tests. Lung volumes and capacities, especially RV and FRC, are increased from the normal value due to air trapping. Figure 12.7 shows the changes in lung volumes and capacities that occur in obstructive pulmonary disease.

Expiratory flow rates, especially FEV₁, are decreased. The ratio of FEV₁ to FVC is also decreased (less than 70%).⁵ These changes in pulmonary function do not show a major reversibility in response to pharmacological agents.

Arterial blood gas analyses may reflect hypoxemia (decreased oxygen in the arterial blood) in the early stages of COPD. Hypercapnea (increased carbon dioxide in the arterial blood) appears as the disease progresses. With disease progression, chest radiographs show several characteristic findings. These include depressed and flattened hemidiaphragms; alteration in pulmonary vascular markings; hyperinflation of the thorax, evidenced by an increased anterior-posterior diameter of the chest; and an increase in the size of the retrosternal airspace, hyperlucency reflecting a decreased tissue density, elongation of the heart, and right ventricular hypertrophy.

The inflammatory reaction in the airways of patients with COPD can also affect other organ systems.¹⁰ COPD is, therefore, not only a pulmonary disorder, but also has extrapulmonary (i.e., systemic) effects, including changes to skeletal muscle mass and function, cardiovascular disease, osteoporosis, and depression.¹¹

Course and Prognosis

The clinical course of COPD has an insidious onset with a disease progression that can progress over many years. Early identification of those individuals at risk for the development of COPD has been elusive. Although smoking is the most prevalent risk factor for the development of disease, not all smokers develop clinically significant lung disease. Therefore, a smoking history in and of itself is not predictive for the development of COPD. Prognostic indicators for mortality include advanced age, need for supplemental oxygen, exercise capacity, and disease distribution within the thorax.¹² The BODE index has been developed as a prognostic indicator for mortality risk in patients COPD. The index uses four domains to calculate mortality risk: body mass index (B), pulmonary obstruction (O), dyspnea (D), and exercise capacity (E).^13,14 This index can be found in Table 12.2. The higher the score on the BODE, the greater the mortality risk. Leading causes of death in patients with COPD are respiratory failure, lung cancer, and cardiovascular disease.¹⁵

Asthma

Asthma is a common chronic pulmonary disease, affecting 300 million people worldwide.¹⁶ The disease is characterized by chronic airway inflammation associated with airway hyperresponsiveness (hyperreactivity) resulting in bronchospasm. Wheezing, breathlessness, and coughing with sputum production that is at least partially reversible in nature are characteristic symptoms of asthma. Asthma exacerbations may improve spontaneously or with medical intervention and are interspersed with symptom-free intervals.

Diagnosis

The diagnosis of asthma is clinically based on a history of episodic wheezing, shortness of breath (SOB), tightness in the chest, and/or coughing, which may be worse at night in the absence of any other obvious cause. The FEV₁ during exacerbations will be less than 80% of the predicted value. With the use of a rescue drug (used to quickly relieve acute symptoms, e.g., inhaled short-acting beta-2 agonist), an improvement of at least 12% (or 200 mL) in FEV₁ indicates reversibility of the airway limitation consistent with a diagnosis of asthma.^16,17 An improvement of PEF of 60 L/min (or greater than 20%) following the use of a beta-2 agonist would also suggest the diagnosis of asthma.¹⁶

Etiology

The etiology of asthma is not completely understood. Historically, two types of asthma have been described. Allergic (or extrinsic) asthma has an immunologic (immunoglobulin E [IgE]–mediated) response to certain environmental triggers (dust mites, pollen, mold, animal dander). The resulting eosinophilic inflammatory response (an increased number of eosinophils found in the airway mucosa) produces the common symptoms and pathophysiological findings of asthma. Atopy, or allergic sensitivity, is the strongest factor for the development of allergic asthma. Nonallergic (or intrinsic) asthma is a less common form of asthma. There are no clinical findings of atopy in nonallergic asthma; however, an inflammatory response does result from exposure to an irritant such as smoke, fumes, infections, or cold air. Literature in asthma has begun to consider that the two types of asthma are not all that different: one has a known and widespread allergic response (extrinsic) whereas the other has a more local inflammatory response (intrinsic).¹⁸ The Global Initiative for Asthma (GINA) does not differentiate allergic from nonallergic asthma in its guide to management and prevention.¹⁶ Viral infections have been suggested to play a role in both the development and exacerbation of asthma.¹⁹ Symptoms of asthma may begin at any age.

Pathophysiology

The major physiological manifestation of asthma is narrowing of the airways in response to a trigger. The airway narrowing occurs as a result of eosinophilic inflammation of the bronchial mucosa, bronchospasm, and increased bronchial secretions. The narrowed airways increase the resistance to airflow and cause air trapping, leading to hyperinflation. These narrowed airways provide an abnormal distribution of ventilation to the alveoli. Even during periods of remission, some degree of airway inflammation is present (Fig. 12.8).

Clinical Presentation

The clinical symptoms of asthma during an exacerbation may include cough, dyspnea on exertion or at rest, and wheezing. The chest is usually held in an expanded position, indicating that hyperinflation of the lungs has occurred. Accessory muscles of ventilation may be used for breathing, even at rest. Intercostal, supraclavicular, and substernal retractions (visible inward motion of the soft tissue) may be present on inspiration. While expiratory wheezing is characteristic of asthma, crackles may also be present. With severe airway obstruction, breath sounds may be markedly decreased owing to poor air movement and wheezing may be present not only during exhalation, but may also become present on inspiration.

Chest radiographs taken during an asthmatic exacerbation usually demonstrate hyperinflation, as evidenced by an increase in the anterior-posterior diameter of the chest and hyperlucency of the lung fields. Less commonly, chest radiographs may reveal areas of infiltrate or atelectasis from the bronchial obstruction. Chest radiographs may be read as normal between asthmatic exacerbations.

The most consistent change during an exacerbation of asthma is decreased expiratory flow rates, both PEF and FEV₁. RV and FRC are increased because of air trapping at the expense of VC and IRV, which are reduced. The reversibility of these pulmonary function test abnormalities is characteristic of asthma. During remission, the patient with asthma may have normal or near-normal pulmonary function tests.

The most common arterial blood gas finding during an asthmatic exacerbation is mild to moderate hypoxemia. Usually some degree of hypocapnea is present secondary to an increased minute ventilation. With severe attacks, hypoxemia will be more pronounced and hypercapnea may occur, indicating that the patient is likely experiencing fatigue and respiratory failure may follow.

Clinical Course

By the time adulthood is reached, many children with asthma no longer have symptoms of the disease.^19,20,21 When the onset of asthma symptoms begins later in life, the clinical course is usually more progressive, showing changes in pulmonary function tests even during periods of remission. Airway remodeling in response to the chronic airway inflammation is thought to be responsible for the progressive nature of the disease.

Cystic Fibrosis

Cystic fibrosis (CF) is a chronic disease that affects the excretory glands of the body. Secretions made by these glands are thicker, more viscous than usual, and can affect a number of systems of the body: pulmonary, pancreatic, hepatic, sinus, and reproductive. Dysfunction of the pulmonary system is the most common cause of morbidity and mortality in patients with CF. Thickened pulmonary secretions narrow or obstruct airways leading to hyperinflation, infection, and tissue destruction. Other presentations may occur due to the effect of this disease on other organ systems such as failure to thrive, diabetes, sinusitis, biliary disorders, and infertility.

Etiology

CF is a genetic disease transmitted by an autosomal recessive trait (Fig. 12.9). The incidence of disease in children is approximately 1 in 3,700 live births in the United States.²² Caucasians make up the majority of all cases of CF in the United States. CF is less common in the Hispanic population (white and black) and is rare in the African American and native American populations.²² The CF gene (cystic fibrosis transmembrane conductance regulator [CFTR]) has been identified on the long arm of chromosome 7. The CFTR functions to transport electrolytes and water in and out of the epithelial cells of many organs in the body, including lungs, pancreas, and digestive and reproductive tracts. Defective transport of sodium, potassium, and water leaves the mucus made by excretory glands thickened and difficult to move, and can often obstruct the lumen of its excretory gland. Over 1,400 mutations of this gene have been described thus far.²³

Pathophysiology

The chronic pulmonary component of CF is related to the abnormally viscous mucus secreted in the tracheobronchial tree. The altered secretions, resulting in airway obstruction and hyperinflation, impair the function of the mucociliary transport system. Exaggerated and sustained neutrophilic airway inflammation in response to infection is also a feature of this disease.²⁴ Partial or complete obstruction of the airways reduces ventilation to the alveolar units. Ventilation and perfusion within the lungs are not matched. Fibrotic changes are ultimately found in the lung parenchyma.

Diagnosis

The diagnosis of CF may be suspected in patients who present with a positive family history of the disease, in patients with recurrent respiratory infections from Staphylococcus aureus and/or Pseudomonas aeruginosa, or with a diagnosis of malnutrition and/or failure to thrive. A chloride concentration of greater than or equal to 60 mEq/L found in the sweat of children is a positive test for the diagnosis of CF. Genotyping for the most common CFTR mutations can also be done, but is usually reserved for patients with borderline sweat chloride test results.

Clinical Presentation

The clinical presentation of CF can be related to any number of involved systems. Failure to thrive due to gastrointestinal dysfunction, diabetes due to pancreatic dysfunction, or frequent respiratory infections and chronic cough from pulmonary dysfunction are all possible presentations of the disease. The severity of the disease, while quite variable, has been linked to the classification of the CFTR mutation.²⁵

With pulmonary involvement, a patient presents with thick bronchial secretions that may be difficult to clear. With advancing disease, the chest wall will become barreled with an increased anterior-posterior (AP) diameter and an increased dorsal kyphosis due to loss of elastic recoil of the underlying lungs and hyperinflation. There is a resultant decrease in thoracic excursion. Breath sounds may be decreased with adventitious sounds of crackles and wheezes. Hypertrophy of accessory muscles of ventilation, pursed-lip breathing, cyanosis, and digital clubbing may all be present.

Pulmonary function studies show obstructive impairments including decreased FEV₁, decreased PEF, decreased FVC, increased RV, and increased FRC. The abnormal ventilation–perfusion relationship within the lungs results in hypoxemia and hypercapnea, as shown by arterial blood gas analysis. As the disease progresses, destruction of the alveolar capillary network causes pulmonary hypertension and cor pulmonale. In advanced disease, chest radiographs show diffuse hyperinflation, increased lung marking, and atelectasis.

Course and Prognosis

Seventy percent of new cases of CF are diagnosed when the child is less than 1 year of age, likely due to mandatory infant testing for CF within the United States. Life expectancy continues to increase owing to advances in early diagnosis and improved medical management. Although some patients unfortunately die in early childhood, 45% of all patients diagnosed with CF are currently older than 18 years of age.²³ The predicted mean survival age of patients with CF was 37.4 years in 2008, a remarkable improvement from a mean survival age of 16 years in 1970.²² Respiratory failure is the most frequent cause of death in patients with CF. Therefore, treatment of the pulmonary dysfunction including removal of the abnormally thick secretions and prompt treatment of pulmonary infections is key to the management of CF. Gastrointestinal dysfunction from CF can be aided by proper diet, vitamin supplements, and replacement of pancreatic enzymes. Habitual exercise has been linked to higher aerobic capacity, increased quality of life, and improved survival.²⁶ Nutritional status is also a powerful predictor of prognosis.²⁷

Restrictive Lung Disease

Restrictive lung diseases are a group of diseases with differing etiologies that result in difficulty expanding the lungs and a reduction in lung volumes. This restriction can arise from (1) diseases of the alveolar parenchyma and/or the pleura; (2) changes in the chest wall; or (3) an alteration in the neuromuscular apparatus of the thorax. For the purpose of this discussion, those diseases most likely to be encountered in a rehabilitation setting—restrictive diseases of the lung parenchyma and pleura—will be presented.

Etiology

This group of disorders has a variety of causes. Numerous agents, such as radiation therapy, inorganic dust, inhalation of noxious gases, oxygen toxicity, and asbestos exposure, can cause damage to the pulmonary parenchyma and pleura and result in restrictive pulmonary disease. The most common restrictive lung disease is idiopathic pulmonary fibrosis (IPF). The etiology of IPF is not known; however, there is an immunological reaction in some cases.

Pathophysiology

The particular changes occurring within the lung parenchyma and pleura depend on the etiological factors of restrictive disease. Parenchymal changes often begin with chronic inflammation and a thickening of the alveoli and interstitium. As the disease progresses, distal airspaces become fibrosed, making them more resistant to expansion (i.e., less distensible). Consequently, lung volumes are reduced. A reduced pulmonary vascular bed eventually leads to hypoxemia and cor pulmonale. Asbestosis (asbestos-induced pulmonary fibrosis) is a type of restrictive lung disease that shows both parenchymal and pleural fibrosis.

Clinical Presentation

Dyspnea with activity and a nonproductive cough are the classic symptoms of parenchymal restrictive lung diseases. Signs of restrictive lung disease include rapid, shallow breathing; limited chest expansion; inspiratory crackles, especially over the lower lung fields; digital clubbing; and cyanosis.²⁸

The plain chest radiograph reveals fine interstitial markings in a reticular, or netlike, pattern. Reduction in overall lung volume and radiographic evidence of pleural involvement, when present, can also be seen on plain chest radiographs, although their diagnostic and prognostic abilities are limited. High-resolution computed tomography (HRCT) is a radiologic test for the diagnosis of IPF that typically shows basilar subpleural changes in a reticular pattern along with traction bronchiectasis (misshapen airways due to a pulling by fibrotic tissue on the airway wall) and honeycombing.^28,29

Pulmonary function tests reveal a reduction in VC, FRC, RV, and TLC. Expiratory flow rates may be somewhat normal. The ratio between FVC and FEV₁ may be normal or even increased. Figure 12.10 shows the changes in lung volumes and capacities that occur in restrictive pulmonary parenchymal disease.

Arterial blood gas studies show varying degrees of hypoxemia and hypocapnea. Exercise may significantly lower oxygenation, even for patients with normal oxygenation at rest.

Course and Prognosis

Restrictive pulmonary disease may have a slow onset but is chronic and relentlessly progressive. Survival depends on the type of restrictive disease, the etiological factor, and the treatment. For patients with IPF mean time from onset of symptoms to death is approximately 80 months. From onset of diagnosis to death is about 35 months.³⁰ Predictors of mortality include age, gender, smoking history, amount of dyspnea, pulmonary function tests, level of oxygenation, and distance walked on a 6-minute walk test.^29,30

Medical management of chronic pulmonary disease includes smoking cessation, pharmacological agents, and the use of supplemental oxygen. The following discussion provides an overview of these medical interventions.

Smoking Cessation

Smoking is the major causal agent in the development of COPD, as well as a contributing cause to many other disease processes. Smoking cessation is the most important intervention for improving the outcomes of patients with COPD.³¹ The addictive properties of smoking and the withdrawal symptoms of smoking cessation make it difficult for smokers to quit. A majority of smokers who try to quit do so on their own. Unfortunately, 94% of those individuals are not successful on their first attempt.³² Smokers report an average of six to nine attempts at smoking cessation before they are successful.³² Using a structured smoking cessation program can increase the success of a person attempting to quit smoking.

There are two general types of smoking cessation programs: behavioral therapy and pharmacological therapy. Behavioral therapy includes education on the benefits of being a nonsmoker, counseling, and support through the arduous process of withdrawing from smoking. Acupuncture and hypnosis are considered part of a behavioral therapy approach because the purpose is to change smoking behavior. Pharmacological therapy includes the use of nicotine replacement therapy and non-nicotine replacement medications such as bupropion (Zyban) and varenicline (Chantix) to assist in the cessation of smoking. Nicotine replacement therapy, using nicotine gum, lozenges, patches, sprays, or inhalers, decreases the withdrawal symptoms linked to nicotine, such as craving for tobacco products, anger, irritability, anxiety, depression, and concentration problems.³³ Bupropion and varenicline counter the withdrawal symptoms of smoking cessation and increase the likelihood of quitting without the use of systemic nicotine.

Smoking cessation without any support has a success rate of approximately 6%. A 2008 meta-analysis regarding smoking cessation found that the use of behavioral therapy had a 14.6% success rate; pharmacological therapy alone had a 21.7% success rate, and a combination of both behavioral and pharmacological therapy had a 27.6% success rate.³⁴ Recommendations for smoking cessation need to be tailored to the individual patient, because access to counseling may be difficult to obtain and adverse reactions to some medications may be encountered. The regional offices of the American Lung Association and the American Cancer Society are good resources for local smoking cessation programs.

Pharmacological Management

Pharmacological agents provide relief from the symptoms of chronic lung disease and improvement in the health and functional status of individuals with lung disease. Each pulmonary diagnosis and the severity of that disease will require a tailored plan of care. It is not unusual for patients to be on a combination of drugs for the management of their pulmonary disease. These drugs can affect exercise performance, HR, and blood pressure (BP), both at rest and with exercise. This discussion will provide information on both maintenance drugs and rescue drugs used in the care of patients with pulmonary disease. Table 12.3 provides foundational information on the pharmacological management of lung disease. Table 12.4 presents the recommended treatments according to the severity of COPD as described by the GOLD standards.⁵ Table 12.5 includes recommendations from GINA for pharmacological control of asthma symptoms.¹⁶

Maintenance Drugs

Maintenance drugs are used to reduce or minimize pulmonary symptoms throughout the day. These drugs are taken on a regular schedule to keep respiratory symptoms at bay. Steroids, anticholinergics, long-acting beta-2 agonists, cromolyn sodium, and leukotriene antagonists are commonly prescribed maintenance drugs for patients with chronic pulmonary disease. Theophylline, though an effective drug for the treatment of chronic pulmonary diseases, is less frequently prescribed because safer medications are available. Routes of administration of maintenance drugs are usually inhalation or ingestion. When inhalation is effective, it is the advisable route of administration because it limits systemic side effects of the drug.

Inhaled or systemic anti-inflammatories, such as steroids, are the mainstay of medical management of the chronic inflammation of asthma.³⁵ Inhaled anticholinergics are commonly prescribed for patients with COPD. The action of an anticholinergic is to block the smooth muscle constriction brought on by the parasympathetic nervous system, thus encouraging bronchodilation. Inhaled long-acting beta-2 agonists are used to mimic the sympathetic nervous system encouraging bronchodilation in patients with bronchoconstriction as a chronic symptom of their pulmonary disease. Inhaled cromolyn sodium is used to prevent the inflammatory response within the respiratory system by stabilizing the mast cell within the alveolar units. Used before an exposure of a known trigger for bronchoconstriction, cromolyn sodium can prevent airway narrowing before it can begin. It is therefore helpful in patients with predictable bronchoconstriction, such as exercise-induced bronchospasm. Leukotriene antagonists are systemic drugs that reduce airway inflammation and relax airway smooth muscle. Again, all of these maintenance drugs are used for the long-term management of chronic lung disease. Among the determinants for use and dosage of maintenance drugs are the severity of disease, the patient's symptoms, and response to the medication.

Rescue Drugs

Rescue drugs are used for immediate relief of breakthrough symptoms of bronchoconstriction (symptoms that "break through" and become apparent despite careful management). Inhaled short-acting beta-2 agonists are used for this purpose. Patients are advised to use their prescribed inhaled short-acting beta-2 agonist on an as-needed basis, rather than on a regular schedule. If a patient reports an increased frequency in the use of a rescue drug, it is indicative of a flaw in the maintenance drug regimen or a change in the patient's pulmonary status. Short-acting beta-2 agonists can be used before the onset of activity to decrease pulmonary symptoms in cases where exercise is the trigger for bronchospasm.³⁶

Although the mechanism of action of each bronchodilator is different, there may be an increase in resting HR and BP with their use. Employing the heart rate reserve method (Karvonen's formula) when prescribing exercise intensity acknowledges the elevated resting HR and an appropriate target HR can be calculated. (See Physical Therapy Management section, Exercise Prescription, for further information.) Other common side effects of bronchodilators include nervousness, tremor, anxiety, and nausea. The side effects of systemic steroids, including osteoporosis, myopathies, and muscle wasting, may require modifications to an exercise program.

Antibiotics

Pulmonary infections are frequent in patients with chronic pulmonary diseases. They can be devastating to the patient and cause major setbacks in pulmonary rehabilitation efforts. The early signs of an infection are often noted by changes in the patient's baseline status (i.e., a change in exercise ability, peak flow rates, dyspnea, color or amount of sputum, or an increase in the use of rescue inhalers). Antibiotics are used to interfere with the growth and/or proliferation of bacteria. The action of these drugs is either bacteriostatic or bactericidal. There are many categories of antibiotics (e.g., penicillins, cephalosporins, tetracyclines) that are effective on different infecting organisms. It is important to identify the infecting organism in order to prescribe the appropriate antibiotic. Prophylactic use of antibiotics has not been demonstrated to prevent infections, and the Alliance for the Prudent Use of Antibiotics (APUA) encourages the use of antibiotics for only diagnosed bacterial infections to reduce antibiotic-resistant strains of bacteria.³⁷

Supplemental Oxygen

The use of supplemental oxygen has been shown to prolong the survival of patients with COPD whose resting arterial partial pressure of oxygen (P_aO₂) is lower than 60 mm Hg.^38,39 An absolute indication for use of long-term oxygen therapy is a P_aO₂ of 55 mm Hg or less, which correlates with an S_aO₂ of 88% or less.⁴⁰ If a patient is limited in the ability to exercise due to dyspnea, supplemental oxygen may be warranted.^38,41 The amount of oxygen used should be titrated individually to maintain an S_aO₂ of at least 90%, if possible.⁴² Various supplemental oxygen delivery methods are available; continuous flow, pulsed flow, and reservoir are among the most common.

Surgical Management

There are few surgical options for the patient with pulmonary disease. Lung volume reduction surgery (LVRS) is a surgical technique that removes nonfunctional, overdistended lung tissue, in order to restore more normal biomechanics to the thorax. LVRS may be indicated in patients with heterogeneous areas of relatively nonfunctional emphysema alongside of functional lung tissue. The surgical procedure removes approximately 20% to 35% of the most diseased lung tissue, relieving the more normal lung tissue of its burden. This surgical procedure reduces RV and FRC (i.e., decreases hyperinflation), allowing for a more normal resting position of the diaphragm, an increased diaphragmatic excursion, and a more normal chest wall motion.⁵ Research has shown postoperative results of increased exercise capacity, lung function, quality of life, and gas exchange in patients with moderate upper lobe lung disease.^5,43 Patients with severe lung disease distributed to other areas of the lung do not appear to benefit equally from this intervention. Rather, they show only slight improvement in functional abilities and quality of life scores with a high mortality rate.^{5,43,44,45,46} Many centers that perform LVRS advocate a preoperative pulmonary rehabilitation program. Participants in these preoperative programs demonstrated shorter hospital stays and fewer days on mechanical ventilation.⁴⁷

Lung transplantation for end-stage pulmonary disease has an overall survival rate of 83% at 1 year and approximately 54% at 5 years.⁴⁸ The goals of lung transplantation are to restore normal lung function, restore normal exercise capacity, and prolong life.⁴⁹ People awaiting a lung transplant include patients with COPD, CF, idiopathic pulmonary fibrosis, and pulmonary hypertension. The number of patients awaiting lung transplantation continues to grow, far exceeding the number of organs available for transplantation, making transplantation a reality for only a small number of individuals.⁴⁸

Chronic pulmonary disease and its associated dysfunction have a slow yet progressive course. The person with pulmonary dysfunction often avoids activities that result in the uncomfortable sensation of dyspnea. A slow but steady decrease in these patients' functional activities follows, resulting in progressive aerobic deconditioning. It is not uncommon for someone with pulmonary disease to have lost many functional abilities before ever seeking medical help. The intended outcome of pulmonary rehabilitation is to interrupt this downward spiraling of physical ability, improve exercise performance, decrease the symptom of dyspnea, and improve quality of life.^50,51,52

Goals and Outcomes

The Guide for Physical Therapist Practice provides a general framework for physical therapy intervention for patients with impaired ventilation, respiration, and aerobic capacity and endurance associated with ventilatory pump dysfunction (Practice Pattern 6F).⁵³ The development of specific anticipated goals and expected outcomes for the individual patient with pulmonary dysfunction can be based on the general goals presented in Box 12.1.

Examination

The examination of a patient's pulmonary status has several purposes: (1) to evaluate the appropriateness of the patient's participation in a pulmonary rehabilitation program; (2) to determine the therapeutic interventions most appropriate for the participant's plan of care (POC); (3) to monitor the participant's physiological response to exercise; and (4) to appropriately progress the participant's POC over time.

Patient History

A patient interview should begin with the chief complaint and the patient's perception of why pulmonary rehabilitation is being sought. Commonly, the chief complaint is often SOB and/or loss of function. A medical history contains pertinent pulmonary symptoms specific to that patient: cough, sputum production, wheezing, and SOB. Occupational, social, medication, and family histories should also be obtained and documented.

Tests and Measures

Vital Signs

HR, BP, oxygen saturation (S_aO₂), respiratory rate, temperature, and presence of pain (usually associated with SOB) should be examined and documented (see Chapter 2, Examination of Vital Signs). An individual's height should be measured, because there is a direct relationship between height and lung volumes. Weight should be measured on a standard scale and each subsequent measurement should be performed on the same scale.

Observation, Inspection, and Palpation

By observing the neck and shoulders of a patient with pulmonary disease, the use of accessory muscles of ventilation can be observed (see Fig. 12.5). A normal configuration of the thorax reveals a ratio of AP to lateral diameter of 2:1. Destruction of the lung parenchyma results in an increase in the AP diameter and a reduction of this ratio (up to 1:1) (see Fig. 12.4). During inhalation and exhalation, both sides of the thorax should move symmetrically; asymmetries should be noted and documented.

Cyanosis is a bluish discoloration of the skin that can be observed periorally, periorbitally, and in nail beds; it indicates acute tissue hypoxia. An indicator of more chronic tissue hypoxia is digital clubbing of the fingers and toes. In digital clubbing, there is an increase in the angle created by the distal phalanx and the point where the nail exits from the digit. The tip of the distal phalanx becomes bulbous (Fig. 12.11).

Auscultation of the Lungs

Auscultation involves listening over the chest wall as air enters and exits the lungs. To perform auscultation of the lungs, a stethoscope is placed firmly on the patient's thorax anteriorly, laterally, and posteriorly (Fig. 12.12). The patient is asked to inspire fully through an open mouth, then to exhale quietly. Inhalation and the beginning of exhalation normally produce a soft rustling sound. The end of exhalation is normally silent. This characteristic of a normal breath sound is termed vesicular. When a louder, more hollow, and echoing sound occupies a larger portion of the ventilatory cycle, the breath sounds are referred to as bronchial. When the breath sounds are very quiet and barely audible, they are termed decreased. These three terms—vesicular, bronchial, and decreased—allow the listener to describe the intensity of the breath sound.⁵⁴

In addition to the description of the intensity of the breath sound, there may be additional sounds and vibrations heard during auscultation. These are called adventitious breath sounds. These sounds are superimposed on the already-described intensity of the breath sound. According to the American College of Chest Physicians and the American Thoracic Society, there are two types of adventitious sounds: crackles and wheezes.⁵⁵ Crackles, historically termed rales and rhonchi, sound like the rustling of cellophane and have a multitude of potential causes (tissue fibrosis, secretions in the airways, and so forth) while wheezes have been described as high-pitched, coarse, whistling sounds. A decrease in the size of the lumen of the airway will create a wheezing sound, much as stretching the neck of an inflated balloon narrows the passageway through which air must escape and produces a whistling sound.

Measurement of Dyspnea and Quality of Life

Quantifying dyspnea at the beginning and the end of a rehabilitation program and during periods of exacerbation can be accomplished using the Baseline Dyspnea Index (BDI) (Table 12.6).^56,57 Quality-of-life (QOL) measures specific to chronic pulmonary dysfunction such as the Chronic Respiratory Questionnaire or the St. George's Respiratory Questionnaire may be helpful in determining the patient's baseline health-related quality of life. The Chronic Respiratory Questionnaire has a subscore for rating dyspnea and the St. George's Respiratory Questionnaire has a subscore for symptoms. Both of these QOL measure as well as the BDI may be helpful in demonstrating improvement made with physical therapy intervention.^58,59

Measurement of Function

Examining a patient's functional abilities at baseline using the 6-Minute Walk Test (6-MWT) or the 10-Meter Shuttle Walk Test (10-MSWT) should be used as an outcome measure to document physical improvements following physical therapy intervention.

Measurement of Strength

Patients with pulmonary disease may show peripheral and ventilatory muscle weakness due to deconditioning, malnutrition, steroid use, and systemic effects of the disease process.^10,11,60 Muscle weakness can contribute to exercise limitations and an inability to perform activities of daily living (ADL). Therefore, measurement of muscle strength (e.g., manual muscle tests) and inspiratory pressures (e.g., PI_max) should be performed to determine the need for strength training during rehabilitation.

Laboratory Tests

Various laboratory studies may be performed to examine patients with pulmonary disease. These include radiology, pulmonary function tests (PFTs) including flow rates, exercise tolerance tests (ETTs), functional performance measures, arterial blood gas (ABG) analysis, S_aO₂ measurements, and electrocardiograms (ECGs).

Exercise Testing in Patients with Pulmonary Disease

A determination of functional capacity is part of the examination of a patient with pulmonary disease. An ETT can provide the objective information to (1) document a patient's symptomatology and physical impairment; (2) prescribe safe exercise; (3) document changes in oxygenation during exercise and determine the need for supplemental oxygen; and (4) identify any changes in pulmonary function during exercise performance. If the ETT is repeated following physical therapy intervention, it can provide important outcome data.

A number of testing methods are available to determine the maximal oxygen consumption and functional abilities of patients with pulmonary disease. An ETT protocol, usually utilizing a treadmill or cycle ergometer, gradually increases exercise intensity to stress the patient with pulmonary dysfunction to the point of limitation. Vital signs are monitored throughout the test. The ECG, continuously displayed during exercise, records the exercise HR and electrical activity of the cardiac conduction system. BP measurements recorded at 1- to 3-minute intervals during exercise and during recovery from the test provide information on the hemodynamic status of the patient. ABGs measured during exercise provide the best method for determining arterial oxygenation and the adequacy of alveolar ventilation, though the invasive nature of this test limits its use. Arterial S_aO₂ monitoring provides less information, but the noninvasive nature of the test makes its use more widespread. Oxygen consumption, VO₂, is a helpful measure that can be collected during an ETT, but requires equipment not always found in an exercise testing laboratory. A number of ETT protocols are outlined in Table 12.7.^{61,62,63,64,65,66} (Refer to the section on exercise testing in Chapter 13, Heart Disease, for more information on exercise protocols.) The symptom-limited ETT requires the patient to continue the exercise protocol until symptoms dictate cessation of exercise. Criteria for stopping a pulmonary exercise test are presented in Box 12.2.

The 10-MSWT is a functional performance measure that uses a recorded audio signal to dictate incrementally increasing walking speeds on a level 10-meter course. Two destination points are placed 10 meters apart. The person is asked to reach each destination point by the time the increasingly frequent audio signal sounds. The results of the 10-MSWT have a positive correlation with VO_{2 max} (maximal oxygen consumption).^67,68

The 6-MWT is also a functional performance measure that asks a patient to walk as far as possible in 6 minutes. The patient is allowed to stop and rest during the administration of the test as total distance walked is the recorded result of the test. The 6-MWT has been shown to be a good predictor of functional abilities.^69,70 Both the 10-MSWT and the 6-MWT are easy to administer, and the ready availability of the required equipment makes them useful outcome measurements to demonstrate changes in a patient's abilities following physical therapy intervention.

Exercise test data provide information that can be used to determine disability, predict mortality, assess the ability to perform ADL, quantify health-related quality of life, determine the need for oxygen therapy, demonstrate the effectiveness of medication changes, and prescribe exercise.^{13,68,69,70,71,72} PFTs performed before and after an exercise test document the effects of exercise on lung function. A reduction of greater than or equal to 10% in FEV₁ is an indication that exercise provoked airway hyperresponsiveness.⁷³ Finally, a prescription for exercise that will safely promote improved cardiopulmonary fitness can be developed based on the ETT.

Exercise Prescription

Exercise prescription incorporates four variables that together allow the therapist to develop a patient-specific exercise formula designed to produce an increase in functional capacity. These variables are mode, intensity, duration, and frequency.

Mode

Any type of sustained aerobic exercise can be used for pulmonary rehabilitation. Lower extremity (LE) activities, including walking, jogging, and cycling, are often used to improve exercise tolerance because these modes of exercise more easily translate into functional abilities. Upper extremity (UE) aerobic exercise (e.g., arm ergometry, free weights) can also be included. The combination of UE and LE training in a rehabilitation program results in improved functional status compared to either exercise alone.⁷⁴ Many programs utilize a circuit approach (combining a variety of resistive and aerobic exercises) to train different muscle groups and maintain the participant's interest.

Intensity

Three parameters can be used to prescribe exercise intensity: oxygen consumption, HR, and rating of perceived exertion (RPE) or rating of perceived dyspnea (RPD). Below is a discussion of each means of prescribing exercise intensity.

Exercise Intensity as a Percent of VO_2max

An ETT may report functional capacity in terms of maximal VO₂. Exercise intensity can be prescribed using a moderate intensity, 40% to 60% of the maximum VO₂ achieved on an ETT, or moderate to vigorous intensity, greater than 60% of the maximum VO₂ achieved on an ETT.⁷⁵ Patients with mild to moderate pulmonary disease may be able to exercise for a period of time at these intensities in order to produce a training effect. However, patients with severe pulmonary disease may not tolerate long periods of activity at high intensities (greater than 60% of their maximum). Lowering the exercise intensity may not be the answer for patients with severe pulmonary disease as using a lower exercise intensity has resulted in a lesser to no training effect.^76,77 Rather, exercise will be tolerated and a training effect achieved when short bursts of activity using a high percentage of a participant's peak workload are interspersed with low-intensity exercise or rest periods.^{75,76,77,78,79,80,81,82,83,84} Current research on interval training versus continuous exercise training is presented in Box 12.3 Evidence Summary. There is a dose relationship between exercise intensity and training outcomes, meaning the higher the exercise intensity, the greater the training.⁵⁰

Exercise Intensity as a Percent of Heart Rate Reserve

While using a percentage of VO₂ may be the most accurate method of prescribing exercise from a graded exercise test, it does not give the clinician a means to monitor exercise intensity during actual performance of the exercise. There is a relationship between increasing workloads, increasing VO₂, and increasing HR, making exercising HR a practical choice for measuring and monitoring exercise intensity.⁸⁵ The target heart rate range (THRR) defines a wide, safe, and effective range of exercise intensity that can be performed during the treatment session. The target heart rate (THR) for a specific patient defines a more narrow HR (within the prescribed THRR) that will be most appropriate to ensure aerobic training and patient adherence.

A common method to determine a patient's THRR and the THR is using the heart rate reserve (HRR) method or Karvonen's formula.⁷⁵ The HRR is the difference between the resting HR (HR_rest) in the seated position and the maximal HR (HR_max) achieved on an ETT. To calculate the THRR, percentages (40% and 85%) of the HRR are added to the resting HR. Karvonen's formula for determining the upper and lower limits of the THRR is:

For example, a person achieves a maximal HR of 165 beats per minute (beats/min) on an ETT. The person's resting HR was 85 beats/min. The HRR is calculated to be 165 (85 = 80 beats/min; 40% of 80 beats/min (32) + resting HR (85) = 117 beats/min; 85% of 80 beats/min (68) + resting HR (85) = 153 beats/min. Thus, for this person, a THRR of 117 to 153 beats/min has been calculated from the exercise test data.

Determination of the appropriate THR is based on a complete patient's history as well as data from all tests and measurements. Patients with mild to moderate pulmonary disease may not have a pulmonary limitation to their ability to perform exercise; therefore, a maximal cardiovascular exercise test is likely to have been performed. If the patient has no other concomitant diseases, has no musculoskeletal or neurological constraints, and is committed to exercise, the higher end of the THRR could be used. For example, if the THRR was determined to be 117 to 153, the THR for this person could be at the high end or 141 to 153. If, on the other hand, the patient had other co-morbidities, such as Musculoskeletal, neurological, or renal issues, and has no exercise experience, then the middle (129 to 141) or even lower (117 to 129) end of the THRR might be used.

Patients with severe pulmonary impairment will likely approach their ventilatory maximum before their cardiovascular maximum is reached; that is, their peak exercise HR may be lower than their cardiovascular HR maximum owing to pulmonary constraints. For these patients, exercise intensities that approach their maximum ventilatory symptoms can be used. This may translate into the upper end of the THRR as calculated by Karvonen's formula or even higher.^61,79 According to the Guidelines for Pulmonary Rehabilitation from the American College of Chest Physicians (ACCP) and the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR), an exercise intensity that uses a high percentage of the patient's peak exercise capacity is well tolerated and physiological training effects have been documented.⁷⁹ However, they caution that lower intensity exercise may be associated with better adherence.⁷⁹ It should be emphasized that exercise intensity, when prescribed by HR, should have an upper and a lower HR limit, not a single number.

Exercise Intensity by Rating of Perceived Exertion or Rating of Perceived Dyspnea

With severe pulmonary disease, dyspnea is often reported as the limiting factor in the patient's ability to perform exercise. Using HR to prescribe exercise, as described in the previous section, does not always directly address the cause of physical limitation in patients with low ventilatory reserve. Borg's RPE is often used as a means of prescribing exercise intensity for patients with cardiovascular and pulmonary diseases.^75,86 Using the RPE scale allows the patient to self-regulate exercise intensity based on his or her perception of exertion (Table 12.8). RPE has been correlated with VO₂, making it a useful means of prescribing and monitoring exercise intensity. Perceived exertion ratings of 3, 4, and 5 were correlated with 60%, 72%, and 78% of VO_2max, respectively.⁸⁰ A variation of the RPE scale uses rating of perceived dyspnea (RPD) as a gauge for exercise intensity^87,88 (Table 12.9). Perceived dyspnea ratings between 3 (moderate SOB) and 6 (between severe and very severe SOB) define the range within which patients with pulmonary dysfunction generally exercise. A rating of up to 3 corresponds approximately to 50% of VO_2max. A rating of about 6 (between 4 and 8) corresponds to approximately 80% of VO_2max⁸⁹ (see also Chapter 13, Heart Disease, for additional information).

Clinicians often prefer to prescribe exercise by utilizing a combination of parameters (e.g., THR and RPE and RPD).

Duration

Exercising within prescribed exercise intensity for at least 20 to 30 minutes is recommended.⁷⁵ The duration of the training session varies according to patient tolerance, with some participants not being able to maintain continuous exercise for 20 to 30 minutes. Frequent rest periods can be interspersed with exercise to accomplish a total of 20 to 30 minutes of discontinuous exercise.

Frequency

The frequency of exercise refers to the number of sessions performed on a weekly basis during the exercise-training period. The frequency of exercise is often dependent on the intensity that can be achieved and the duration that can be maintained. If 20 to 30 minutes of continuous aerobic exercise can be accomplished within the THR, then three to five evenly spaced workouts per week are recommended. More frequent exercise sessions are recommended for patients with lower functional abilities. One to two daily sessions are advisable for patients with very low functional work capacities.

Pulmonary Rehabilitation

Aerobic Training

The aerobic exercise training portion of a pulmonary rehabilitation session includes the following components: check-in, warm-up, aerobic exercise, and cool-down. The check-in period is a time to obtain baseline data, including resting HR, respiratory rate, BP, oxygen saturation, auscultation of the lungs, and weight. It is also the time to discuss medication schedules, any problems the patient may have encountered since last visit, and any changes that need to be addressed by a member of the pulmonary rehabilitation team, such as a change in flow rates, cough, or sputum production. If the patient were found to have a significant decrease in FEV₁ on the ETT, a maintenance drug would typically be prescribed to reduce or minimize pulmonary symptoms. PFTs with a handheld device may be performed pre and post exercise to assess the impact of the maintenance medication. The potential need for use of a beta-2 adrenergic inhaler before exercise should be determined. If a patient is found to have a significant decrease in oxygenation with exercise, supplemental oxygen should be readied before initiation of physical activity.

The warm-up component is a time to slowly increase the HR and BP to ready the cardiovascular system for aerobic exercise. For those patients with mild to moderate lung disease who had a cardiovascular end point to their exercise test, the warm-up is usually accomplished by performing the same mode of exercise that will be used in the aerobic portion of the program but at a lower intensity, with an emphasis on controlled breathing. For example, cycling with no resistance could be used as a warm-up activity for a biking program. The warm-up for patients performing continuous exercise lasts between 5 and 10 minutes. For patients with severe lung disease who are prescribed short bursts of high-intensity exercise, there is little opportunity for a warm-up. In these situations, the program should be designed so that each exercise bout of the circuit gradually builds on the previous exercise to ramp up activity.

The aerobic portion of the exercise session consists of a mode or modes of aerobic activity at the appropriate intensity to maintain the THR of the exercise prescription for the advised duration. This portion of the program lasts for at least 20 minutes of either continuous or discontinuous activity. Participant monitoring can be accomplished using RPE and RPD scales, and measures of HR, respiratory rate, and S_aO₂ (oximetry).

The aerobic training period should be followed immediately by a cool-down period consisting of a slow decline in exercise intensity as the patient nears completion of the circuit. This may consist of 5 to 10 minutes of low-level aerobic activities that slowly return the cardiovascular system to near pre-exercise levels or ramping down of the intensity of short bouts of exercise. Again, there is an emphasis on controlled breathing.

Finally, stretching exercises are performed to maintain joint and muscle integrity and to help prevent injury. Stretching exercises should be performed during exhalation to prevent a Valsalva maneuver, which would worsen a participant's pulmonary capabilities. Patients often use accessory muscles of ventilation during the exercise program; therefore, the muscles of the neck and UEs should be incorporated into the stretching program.

General Strength Training

Extremity Training

While cardiopulmonary endurance training through aerobic exercise is the mainstay of pulmonary rehabilitation, generalized strength training has been found to counter the systemic effects of COPD that result in peripheral and ventilatory muscle weakness. Strength of both UEs and LEs has been shown to increase with appropriate training. Strength training can use similar modes of exercise as the endurance training with a change to higher resistance and lower repetitions (i.e., increase the grade of treadmill, increase resistance on stationary cycle or arm ergometer), or weight training of the targeted muscle groups can be prescribed. Participants should be encouraged to refrain from using the Valsalva maneuver during training because this may impair ventilatory exchange and affect exercise performance.

Ventilatory muscle training

Patients with COPD may have weak inspiratory muscles that translate into breathlessness and exercise limitations.⁷⁹ Ventilatory muscle training devices provide resistance to the inspiratory phase, the expiratory phase, or both phases of ventilation in order to increase the strength and endurance of the muscles of ventilation. Figure 12.13 shows one type of ventilatory muscle training device (Philips Healthcare, Andover, MA). Many research studies have demonstrated the ability to increase ventilatory muscle strength and endurance using these loading devices, especially in the presence of known respiratory muscle weakness.^{90,91,92,93,94} Ventilatory muscle trainers have also been studied for their ability to alter the perception of dyspnea. A number of researchers have demonstrated a decrease in the severity of dyspnea with ventilatory muscle training during the performance of ADL and during exercise.^92,95,97,98 Current research on the benefits of ventilatory muscle training can be found in Box 12.4 Evidence Summary.

Whether training the muscles of ventilation alone translates directly into a clinically significant functional improvement is still not clear. Statistically significant changes in 6-MWT and 10-MSWT data have been demonstrated with ventilatory muscle training.^92,93,95,98 However, these changes do not always translate into a clinically significant improvement. For example, a change of greater than 54 meters needs to be realized on a 6-MWT in order to be clinically significant.⁶⁹ Although Hill et al⁹⁸ found a statistically significant increase in distance on the 6-MWT in those patients in the ventilatory muscle treatment group, the increase was less than 54 meters, meaning that the increase may not be of clinical value. Following a meta-analysis, Lotters et al⁹⁰ indicate that the ability to affect functional improvement by the use of ventilatory muscle training is yet to be determined. In patients with severe pulmonary disease and documented ventilatory muscle weakness, training improved their ventilatory muscle strength and endurance and decreased dyspnea.^79,94 However, in patients with mild to moderate pulmonary disease, training did not significantly improve ventilatory muscle function. The use of a specific ventilatory muscle training device should be made individually, based on the type of disease, the severity of disease, the presence of inspiratory muscle weakness, and the motivation of the participant.⁷⁹

Exercise Progression

A patient's age, functional ability, symptoms, and severity of disease should be considered before any change in the exercise prescription. Exercise progression is appropriate when the individual perceives the exercise session to be easier (lower RPE or target dyspnea) or when the same exercise workload is performed with a lower HR, that is, as the individual physiologically adapts to exercise.

Exercise progression should first be directed toward increasing the number of continuous minutes of exercise and decreasing the amount of time spent in low-intensity exercise or rest periods. When 20 minutes of continuous activity can be accomplished, an increase in exercise duration or intensity can be proposed. Frequency should be adjusted as necessary, based on duration and intensity.

Program Duration

Improved exercise tolerance can occur in multiple settings: an inpatient rehabilitation hospital program, an outpatient pulmonary rehabilitation program, or a home-based program.¹ Because of the limited length of stay for many inpatient rehabilitation hospital admissions, most increases in functional capacity occur in an outpatient or home pulmonary rehabilitation program. Generally, conditioning exercises are conducted up to three times per week over a course of 6 to 12 weeks.⁷⁹ At the end of the rehabilitation program, QOL measurements and dyspnea measurements should be readministered to assess the benefits of pulmonary rehabilitation for each participant. A follow-up 6-MWT or a 10-MSWT should be repeated at the end of the program to assess the change in aerobic conditioning of each participant. Exercise abilities gained in a pulmonary rehabilitation program have been found to gradually decline over 12 to 18 months following completion of the program. Pulmonary rehabilitation programs that last longer than 12 weeks have shown greater sustained benefits than shorter programs.⁷⁹

An unfortunate reality is that patients with pulmonary dysfunction often have decreased exercise ability following an exacerbation of their disease. It is currently not clear that repeated bouts of pulmonary rehabilitation are beneficial to patients with pulmonary disease.⁹⁹ Continued support in the form of self-help groups and community exercise groups is essential to maintaining the new level of physical activity obtained with pulmonary rehabilitation.¹

Home Exercise Programs

A home exercise program (HEP) begins while the participant is enrolled in a pulmonary rehabilitation program. When deemed appropriate (based on exercise response and laboratory data), the participant can be assigned home exercise activities. The patient uses an exercise log to record parameters such as exercise HRs, RPEs, exercise workloads, and any questions that may arise about the HEP (Fig. 12.14). At regular intervals, the therapist analyzes the data and adjusts the HEP as necessary. Progression to an independent HEP is an important rehabilitation goal to promote a participant's lifelong commitment to exercise.

Multispecialty Team

Although aerobic exercise training is integral to pulmonary rehabilitation, patients require additional services and information to optimize their exercise capability and to improve quality of life. The following sections address other elements of a pulmonary rehabilitation program: patient education, secretion removal techniques, and activity pacing. Smoking cessation should also be considered as a component of pulmonary rehabilitation. (See the section on smoking cessation in the medical management section of this chapter.)

Patient Education

The concept of self-management is promoted in the individual and group educational sessions of a pulmonary rehabilitation program.⁷⁹ Participants are given individual, one-on-one time to identify their own needs and address issues that are particular to themselves. Benefits from group discussions include support from peers regarding the patient's feelings or needs, learning from others' experiences and questions, and the socialization only a group can provide. Key components of a patient's education program are presented in Box 12.5.

Education makes it possible for patients to assume the responsibility for their own wellness. A patient will carry out the required activities to produce the desired outcome only if the patient knows what to do, knows how to do it, and also wants to do it. This theory of self-efficacy for the patient with pulmonary disease begins with a daily routine that includes self-assessment, adherence to a medication schedule, performance of airway clearance techniques, ADL with pacing, and an appropriate HEP.

Self-assessment is used to recognize the first sign of an exacerbation of the disease: increased dyspnea, decreased exercise tolerance; change in pulmonary flow rates, sputum color or consistency; pedal edema; or any other significant change from baseline. An exacerbation protocol is individually devised that includes a set of standard instructions consistent with the participant's disease and abilities. These instructions may include the use of airway clearance techniques, pacing techniques, or a change in the exercise prescription, as well as contact with the primary care physician for a review of symptoms and pharmacological management.

Managing lung disease can be taught through educational programs that address the needs of individuals with pulmonary disorders. Compared to general education alone, education as part of an individualized comprehensive pulmonary rehabilitation program produced significantly improved exercise abilities, decreased dyspnea, and greater self-efficacy.¹⁰⁰ Once the patient has progressed through pulmonary rehabilitation, access to new information and continued support is possible through community support groups (e.g., the Better Breathing Club, sponsored by the American Lung Association).

Secretion Removal Techniques

Secretion retention can interfere with ventilation and the diffusion of oxygen and carbon dioxide in some patients with pulmonary disease. Patients with secretion retention may improve their exercise performance if proper secretion removal techniques have been performed before the physical activity. The preferred practice pattern from the Guide to Physical Therapist Practice for these individuals would be 6C-1: Impaired ventilation, respiration, and aerobic capacity associated with airway clearance dysfunction.⁵³ An individualized program of secretion removal techniques directed to the areas of involvement can optimize ventilation and therefore gas exchange capabilities. Secretion removal techniques include dependent programs that rely on a caregiver (postural drainage, percussion, and shaking) or independent programs, such as the active cycle of breathing technique (ACBT); positive expiratory pressure (PEP), such as the TheraPEP® PEP Therapy System (Smiths Medical, Dublin, OH); airway oscillation devices, such as the Flutter® (Cardinal Health, Dublin, OH) or the Acapella® (Smiths Medical, Dublin, OH); or high-frequency chest compression (HFCC) devices such as The Vest® System (Hill-Rom, St. Paul, MN).

Manual Secretion Removal Techniques

Postural Drainage

Positioning a patient so that the bronchus of the involved lung segment is perpendicular to the ground is the basis for postural drainage. Using gravity, these positions assist the mucociliary transport system in removing excessive secretions from the tracheobronchial tree. Standard postural drainage positions are presented in Fig. 12.15. Although these postural drainage positions are optimal for gravity drainage of specific lung segments, such positioning may not be realistic for some patients. Modification of these standard positions may prevent any untoward effects yet still enhance secretion removal. Box 12.6 lists precautions that should be considered before instituting postural drainage with patients with signs and symptoms of increased daily pulmonary secretions. These are not absolute contraindications, but relative precautions. The list is not meant to be inclusive; however, it does provide a range of considerations that should be addressed before instituting postural drainage.

Percussion

Percussion is a force rhythmically applied with the therapist's cupped hands to the patient's chest wall. The percussion technique is applied to a specific area on the thorax that corresponds to an underlying involved lung segment. The technique is typically administered for 3 to 5 minutes over each involved lung segment. Percussion is thought to release the pulmonary secretions from the wall of the airways and into the lumen of the airway. By coupling percussion with the appropriate postural drainage position for a specific lung segment, the probability of secretion removal is enhanced. Because percussion is a force directed to the thorax, there are conditions that would necessitate caution with this technique, such as a fractured rib, a flail chest, osteoporosis, elevated coagulation studies, or a decreased platelet count. These examples are by no means inclusive, but they provide some patient presentations that might require modification (a gentler force applied to the thorax) or elimination of the percussion technique.

Shaking

Following a deep inhalation, a bouncing maneuver is applied with the therapist's open hands to the rib cage throughout the expiratory phase of breathing. This shaking is applied to a specific area on the thorax that corresponds to the underlying involved lung segment. Five to seven deep breaths with shaking on exhalation are appropriate to hasten the removal of secretions via the mucociliary transport system. Shaking is commonly used following percussion in the appropriate postural drainage position. Because this technique consists of a force applied to the thorax, the same circulatory and musculoskeletal considerations are needed as in the application of percussion.

Airway Clearance

Once the secretions have been mobilized with postural drainage, percussion, and shaking, the task of removing the secretions from the airways is undertaken using an airway clearance technique. Coughing is the most common and easiest means of clearing the airway. However, it should be noted that high intrathoracic pressures, such as those generated during coughing, could force the closing of small airways in some patients with obstructive pulmonary diseases. By trapping air behind the closed airway, the forced expulsion of air during a cough becomes ineffective in clearing secretions. Huffing is an alternative method of airway clearance that is useful for patients with obstructive pulmonary disease. A huff uses many of the same steps of coughing, without creating the high intrathoracic pressures. The patient is asked to take a deep breath and then rapidly contract the abdominal muscles while forcefully saying "HA HA HA." This allows a forced expiration through a stabilized open airway and makes secretion removal more effective.¹⁰¹

Active Cycle of Breathing Techniques

ACBT is an independent breathing exercise program the patient can perform to clear secretions from the airways that includes (1) a breathing control phase; (2) thoracic expansion exercises; and (3) a forced expiratory technique. ACBT begins with a few minutes of the breathing control phase, defined as relaxed, diaphragmatic, tidal volume breathing. Three to four thoracic expansion exercises, defined as deep inhalations with a 3-second hold followed by a passive exhalation, are performed next. A return to the breathing control phase follows. Depending on the patient's needs, this breathing control phase can last for seconds to minutes. If the patient feels that there are secretions ready to be moved upward, then the forced expiratory technique completes the cycle. If secretions are not ready to be moved, the patient returns to thoracic expansion exercises followed by another period of breathing control for rest and for the patient to assess the status of secretions is their airways. The forced expiratory technique, defined as one or two huffs from tidal volume down to low lung volumes, is used to move secretions higher into the larger airways. The forced expiratory technique is followed by a rest period of breathing control. Using ACBT, secretions are "milked" from smaller to larger airways. Once the secretions have moved into the larger airways, huffs from mid or high lung volumes remove the secretions from the airways. This independent technique has been demonstrated to be as effective as postural drainage, percussion, and shaking.¹⁰² Figure 12.16 emphasizes that the patient begins at breathing control and always returns to breathing control for rest and the patient's own assessment of his or her status before moving to either thoracic expansion with breath hold or the forced expiratory technique.

Oral Airway Oscillation Devices

Airway oscillation devices, such as the Flutter® or the Acapella® (Fig. 12.17), alter the exhaled airflow throughout the airways. The patient inhales a normal size breath. During active exhalation through the device, the exhaled air causes an intermittent backward air pressure that jars the airways. The usual procedure is to exhale 10 or so breaths through the device, followed by two large exhaled volumes through the device and finally a huff or cough to clear mobilized secretions. This routine is repeated until secretions are cleared from the lungs. An airway oscillation device has been shown to help in the removal of secretions from airways.^103,104

Positive Expiratory Pressure

PEP devices include a valve to regulate expiratory resistance (Fig. 12.18). Inhalation of a normal size breath through the mask or mouthpiece is unresisted. Active exhalation is against a positive expiratory pressure, measuring 10 to 20 cm H₂O. A treatment session lasts approximately 10 to 20 minutes with frequent pauses to remove the mask so that the patient can huff to clear secretions. The session is completed when all secretions have been cleared from the airways. PEP has been shown to be as effective as postural drainage, percussion, and shaking.^105,106

High-Frequency Chest Compression Devices

HFCC devices use an inflatable vest with air channels that is worn over the patient's thorax (Fig. 12.19). The vest is attached to an air compressor that rapidly delivers small air volumes in and out of the vest. The inflation of the vest causes compression to the chest wall and the deflation allows the chest wall to recoil back to its resting position. The patient assumes a comfortable seated position for treatments lasting between 20 and 30 minutes. Secretions may be huffed clear any time throughout the treatment. High-frequency chest wall compression has been shown to be as effective as other secretion removal techniques.¹⁰⁷

Breathing Exercises

Pursed-lip breathing involves an unresisted inspiration followed by an active oral exhalation through a narrowed (or pursed) mouth opening. When pursed-lip breathing is used by patients with COPD, it may delay or prevent airway collapse, allowing for better gas exchange.^108,109 Most patients demonstrate this strategy during periods of dyspnea and rarely need to be taught the technique.

Although diaphragmatic breathing has been taught to patients with chronic pulmonary dysfunction for years, there is little evidence to support its use to improve pulmonary mechanics.¹⁰⁹ Some patients require the use of accessory muscles with exercise, with exacerbation of their disease, or with periods of dyspnea. Strengthening accessory muscles of ventilation may be a more effective treatment program than encouraging the use of an ineffective diaphragm with little ability to generate muscle force and/or limited muscle excursion. In patients with very flat diaphragms, focusing on diaphragmatic breathing may even be detrimental.

Activity Pacing

Activity pacing refers to the performance of any activity within the limits or boundaries of that patient's breathing capacity. For example, an activity that usually causes dyspnea needs to be broken down into component parts such that each component can be performed at a rate that does not exceed breathing abilities. By breaking activities down into component parts and interspersing rest periods between each component, the total activity can be completed without dyspnea or undo fatigue. For example, patients often find that climbing stairs causes a great deal of dyspnea and discomfort. Rather than climbing the entire flight of stairs (usually done too fast and with a breath hold), the patient might be instructed as follows: "Take a deep breath. Now, on exhalation, walk up one (or two or three) stair(s). Now recover. Take in another good breath and walk up the next one (or two or three) stair(s) and recover. Repeat this technique until the flight of stairs is completed." The patient is able to reach the top of the stairs without becoming dyspneic and without undue fatigue. Pacing can and should be part of every activity that would otherwise cause dyspnea. Pacing should be used when performing ADL, ambulation, stair climbing, and other daily tasks. Pacing is not a technique to be used during the aerobic portion of a pulmonary rehabilitation program. During exercise, some shortness of breath is expected to occur.

Pulmonary rehabilitation programs are a well-established treatment for patients with chronic pulmonary disease. Components of these programs typically include exercise training, strength training, education, secretion removal instruction, and psychosocial support. Outcomes of pulmonary rehabilitation may include increased aerobic capacity, increased skeletal muscle strength, reduced dyspnea both during exercise and ADL, and an increase in the perception of health-related quality of life. Gains made in pulmonary rehabilitation programs can make the difference between a lifestyle of dependence and one of independence. Physical therapists have the important role of evaluating patients, determining their potential, and, through exercise prescription and exercise programs, ensuring that rehabilitation goals and outcomes are realized.

Questions for Review

1. How does the clinical presentation of obstructive lung disease differ from the clinical presentation of restrictive lung disease?

2. Explain how altered airway structure leads to airflow limitation.

3. (a) What would be the expected breath sounds of a patient with COPD (describe intensity and adventitious sounds)? (b) What would be the expected breath sounds of a patient with asthma during an exacerbation (describe intensity and adventitious sounds)?

4. Identify the tests and measures required to determine the extent of pulmonary disease.

5. What are the pulmonary end points to a symptom-limited graded exercise test?

6. How does exercise prescription differ for a patient with mild pulmonary disease as compared to the patient with severe pulmonary disease?

7. (a) How do you know when to progress a patient's exercise program? (b) What is the nature of that progression? (c) Do you need a new ETT to progress a patient's exercise workload?

8. How would you respond to a patient's comment that it would take longer to climb stairs with pacing than without?

9. Design a secretion removal treatment plan for a patient with CF that can be carried out independently before coming to pulmonary rehabilitation.

10. What evidence is presented in the current literature regarding the benefits of pulmonary rehabilitation?

A 67-year-old white female was admitted to the hospital with a diagnosis of acute bacterial pneumonia. She was treated with mechanical ventilation for 5 days, steroids, antibiotics, and bronchodilators. After the acute care hospital stay of 7 days, the patient was transferred to an inpatient rehabilitation facility for 7 days. She is now referred to outpatient pulmonary rehabilitation.

PAST MEDICAL HISTORY

COPD, pneumonia four times over the past 2 years, s/p lumpectomy of right breast 8 years ago, smoking history of 45 pack/years; quit on day of admission to hospital for acute bacterial pneumonia.

MEDICATIONS

2 L/min of pulsed oxygen, Atrovent (maintenance, anticholinergic) 4 puffs qid, albuterol (rescue, beta-2 adrenergic) 2 puffs PRN, prednisone (maintenance, anti-inflammatory) 5 mg/day.

OCCUPATION

Secretary, works 32 hours/week. Presently on medical leave.

SOCIAL AND ENVIRONMENTAL

Lives with husband in own home. Three steps to enter home, 12 stairs within the home.

OBJECTIVE FINDINGS

Interview

Mental status: awake, alert, talks in three- to four-word sentences. Adequate historian. Chief complaint: shortness of breath limiting function. Patient is able to walk 150 ft before needing to rest to catch her breath. No complaints of increased secretions. Baseline dyspnea index: functional impairment, grade 1; magnitude of task, grade 1; magnitude of effort, grade 1 (see Table 12.6). Patient reports an RPE of 6 (the Borg 0–10 Scale) with one flight of stairs. Patient is dependent in shopping, house cleaning, and laundry. St. George's Respiratory Questionnaire was administered with a score of 54. Patient's desired functional outcome is to be oxygen free and able to care for grandchildren without shortness of breath.

Vital Signs

HR 72, BP 96/74, S_aO₂ at rest 86% on room air, 98% on 2 L/min pulsed O₂ on 1 pulse/breath, respiratory rate 32, temperature 98.5°F.

Observation, Inspection, Palpation

Thin, frail-looking female wearing nasal cannula; kyphosis noted. Patient uses posture of forward sitting with arms supported on chair arms to enhance ventilatory accessory muscle use. Increased AP diameter of thorax, accessory muscle use at rest; labored, symmetrical breathing pattern with pursed-lip breathing. No venous distention, no edema, no cyanosis, minimal clubbing evident.

Auscultation

Decreased breath sounds throughout both lung fields, especially at bases. End expiratory wheezes at left lateral base.

Strength

Bilateral LE manual muscle testing: hip flexion 3+/5, knee extension 3+/5, plantarflexion 3+/5, dorsiflexion, 4/5. Bilateral shoulder elevation, abduction, elbow flexion, wrist flexion and extension, 3+/5. Patient unable to lie prone or supine for further testing secondary to orthopnea. Alternative positions were used to assess the strength of other muscles: all other muscle groups able to move against gravity and able to accept moderate resistance. Maximal inspiratory effort (PI_max) 52 mm Hg; SIP_max 26 mm Hg.

Exercise Test Data

Patient performed a 7-minute, staged (3 min/stage) treadmill exercise test using a modified protocol. Treadmill speed was held constant at 2 mph, grade increased from 0% (stage 1) to 2% (stage 2) to 3% (stage 3). ECG was within normal limits. HR_rest was 84 beats/min, HR_peak 121 beats/min. On 2 L pulsed O₂, S_aO₂ resting 98%, 93% at max exercise, 90% during the first minute of cool-down, returned to baseline within 4 minutes of recovery. Rate of perceived exertion at peak exercise was 7 (1–10 scale). Rate of perceived dyspnea at peak exercise was a 9. Exercise was terminated due to patient complaint of shortness of breath. Single-breath TV measurement just before ending test was .99 liters with a respiratory rate of 36 breaths/min. There was no change in pulmonary function tests after exercise. 6-Minute Walk Test: 200 m on 2 liters pulsed O_2.

Laboratory Test Data (after bronchodilator)

1. In what stage of GOLD does this patient present?

2. Did the pulmonary system or cardiovascular system stop her exercise test?

3. Identify this patient's impairments, functional limitations, and disability restrictions. Identify general anticipated treatment goals and expected outcomes for a 3-month (12-week) pulmonary rehabilitation program. Identify outcome measures that will be used to assess the effectiveness of a pulmonary rehabilitation program.

4. Formulate a physical therapy plan of care for week 1. Patient will be seen 3 times/week for this first week of therapy. Briefly describe exercise progression for the first month of the program.