Successfully rehabilitating patients with lung disease involves a multidisciplinary team of health care professionals providing all aspects of care.
In the age of managed health care plans, short hospital stays, and expensive medications, the need to understand the place and utility of pulmonary rehabilitation is magnified. The ability to keep people gainfully employed and healthy should be the goal of all health care providers and should certainly be a high priority for insurers/payors as well. Since the prevalence of smoking-related lung disease and of a variety of forms of reversible obstructive lung disease continues to increase, so does the importance of this modality of coordinated therapy.
In 1974, the American Thoracic Society published the following definition of pulmonary rehabilitation: Pulmonary rehabilitation may be defined as an art of medical practice wherein an individually tailored, multidisciplinary program is formulated, which through accurate diagnosis, therapy, emotional support, and education stabilizes or reverses both the physio- and psycho-pathology of pulmonary diseases and attempts to return the patient to the highest possible functional capacity allowed by his pulmonary handicap and overall life situation.1
In this definition, it is clear that a rehabilitation program has to be carried out by a multidisciplinary team of health care professionals. The main aim of this team is to improve the disease state of chronic airway obstruction (CAO) patients so they may become independent to the greatest extent possible. Although most rehabilitation programs are designed for patients with mainly obstructive airways disease, patients with other forms of lung disease can likewise participate and benefit.2
Natural Course of CAO
Symptomatic CAO accounts for the great majority of lung disease in this and most other developing countries. Its prevalence is rising and is related, at least in part, to our aging population, to the continued high incidence of new smokers in the population base, and to the large number of new chemical/industrial compounds and by-products introduced yearly into our environment. Because of this pollution, occupational asthma is now almost a subspecialty interest within the specialty of pulmonary medicine. Our discussion will be focused on the rehabilitation of CAO because most of the large-scale studies and thus the data available come from this population of patients.
Much has been documented about the natural decline in lung function that occurs both normally and in those with some form of CAO. Since the normal, healthy human lung has such great reserve, the yearly loss of 20 to 30 mL never impairs function to the extent of causing physical impairment, even into old age. However, patients who have established CAO, with FEV1 readings of <60% of predicted lost lung function at an accelerated rate, decreasing by 40 to 100 mL per year, with values up to 200 mL per year have been reported by some.3 One can extrapolate life expectancy from these data with a fair degree of certainty, yet there are modalities involved in the care of these patients that may both slow the progression of this process and, at the same time, improve the quality of life to a significant degree. A formalized, multidisciplinary pulmonary rehabilitation program, generally conducted in an outpatient, user-friendly setting, attempts to meet these goals.
Program Goals and Efficacy Data
One of the misunderstandings concerning pulmonary rehabilitation is that it in some way measurably improves lung function or it is of no value. Nothing is further from the truth. Although a certain percentage of patients will show improvement in FEV1, MVV, and some in FVC, these changes usually occur because of a greater understanding of how to properly use inhaled medication, increased compliance with medications after a formal instructional program, or the use of anti-inflammatory agents recommended by many rehabilitation programs.
One great benefit for this patient group as a whole, however, is simply reducing the rate of pulmonary function decline.
The Dutch experience2 has best shown the contrast between former smokers and continued smokers in regard to decline in lung function. Note that at 10 years of follow-up, 50% of patients with established CAO who continue to smoke have succumbed, whereas only 20% of those who stopped have died. These findings indicate the critical nature of having an aggressive smoking cessation clinic as part of any effective rehabilitative effort.
Reduction of Airway Hyperresponsiveness
In the group of patients who have a significant initial degree of reversibility, the long-term prognosis seems better with the regular, scheduled use of inhaled bronchoactive agents. Subsets respond best to beta agonists, while other subsets have been found to respond more dramatically to anticholinergic agents that more directly affect large airway flow rates.4-6 Antiinflammatory use in the form of oral and/or inhaled steroids has well-established utility in pure asthmatic subjects, but studies have now established utility in some, but not all, patients with chronic bronchitis and mixed bronchitis/emphysema.7,8 A trial of 6 to 8 weeks of oral steroids and of 6 to 8 months of inhaled steroids with pre- and post-study comparisons can identify those who will respond to these agents. Oral cortico-steroids are, however, best limited to early use during periods of exacerbation of the underlying lung disease. Salmeterol has the unique dual property of long-term bronchodilation and being an antiinflammatory. In some patients with CAO who also suffer from anxiety, hypertension, angina, and/or arrhythmias, this agent may be well tolerated whereas use of plain beta agonists is actually contraindicated. With both smoking cessation and antiinflammatory medications, cough and expectoration decline, as does the frequency of purulent, infective exacerbations of bronchitis. Naturally, this positively impacts the patients overall health status, his or her exercise tolerance, frequency of need for health care intervention, and sense of well-being.
Exercise Tolerance/Energy Conservation
Of all the consistent benefits shown in the majority of reports concerning efficacy of pulmonary rehab, improvement in exercise tolerance is perhaps the greatest. Results of the 6- and 12-minute walk tests are improved in more than 80% of rehabilitation patients who have been preselected to exclude those with established signs and symptoms of cor pulmonale and/or right heart overload on an electrocardiogram. Educational classes teaching patients to control panic breathing and to replace it with pursed lip breathing, coupled with expiratory resistive exercises, should run in conjunction with a five- or six-stage aerobic exercise program. In the Baptist Health System of Alabama rehabilitation programs, we include: the treadmill, arm crank, exercycle, rowing machine, steps, and track. During exercise, patients are monitored by telemetry with periodic transcutaneous oximetry checks. The addition of oxygen for anyone who has shown a tendency toward desaturation on prerehab testing ensures an adequate substrate for the conditioning effect. A metabolic stress test with exercise gas exchange data is done to document abnormalities that affect safety, such as hypertensive blood pressure rises, ischemic electrocardiographic changes, induction of arrhythmias, signs of right heart strain or production of respiratory (fall in Pao2 and saturation below 65 mm Hg and 90%, respectively) or ventilatory (rise in pCO2 to >50 mm Hg) failure. If skeletal muscle becomes oxygen-starved with light exercise, with early production of lactic acid, the conditioning effect of exercise will be negated. Therefore, the determination of exercise-related desaturation prior to entry into the program is, in our view, mandatory.9 The addition of nasal oxygen and the telemetric monitoring of pulse rate and rhythm bring both safety and efficacy to the rehabilitation process. Teaching energy conservation is important in these patients with more advanced disease who, despite an 8- to 12-week rehabilitation effort, remain quite limited in their daily activity performance.
Daily and Rescue Use of Medications
As any rehabilitation nurse or respiratory therapist will affirm, a surprising percent of patients with long-standing CAO do not properly use metered dose inhalers, wasting or else overusing costly and potentially toxic medication. Many do not know what they should do to avoid a potential visit to the emergency department or to attenuate an early problem by the systematic use of a rescue program that may, depending on the patient and the individual situation, call for such measures as:
notifying a care partner of difficulty breathing;
hourly liquid consumption;
hourly use of a metered dose of a short-acting beta agonist for three to four treatments;
doubling of an inhaled steroid and/or institution of a burst and taper of a predetermined 5- to 7-day course of oral steroids; and
self-administration of a broad-spectrum antibiotic for even low-grade fever, increased cough, dyspnea at rest, and change in the amount or content/character of sputum. Careful instruction in the above in an applied fashion reduces the frequency of serious exacerbations, shortens illness, and conserves important resources. Many patients attest to the confidence they have gained in learning such important procedures.
Pulmonary rehabilitation takes effort and a great deal of organization, but the benefit to patients who suffer daily from chronic obstructive lung disease, with its attendant depression, loss of self-esteem and independence, use of resources, and the fear of suffocation, make it well worth our efforts. Lung function is improved in some, but the lessening of symptoms in most patients, the slowing of pulmonary function deterioration, the improvement in use of various medications, the improvement in exercise tolerance, independence, and mental outlook, and reduction in overall health care costs make this a vital form of therapy.
Frank D. Sutton, MD, is the director of pulmonary rehabilitation at Baptist Health Systems of Alabama, Birmingham.
1. American Thoracic Society. Pulmonary rehabilitation. Am Rev Respir Dis. 1981;124:663-666.
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