Respiratory rehabilitation in chronic bronchopulmonary diseases

 

 

1Department of Health Care Faculty of Public Health, Health Care and Tourism, National Sports Academy "Vassil Levski" - Sofia, Bulgaria

2Department of Physiotherapy and Rehabilitation, Faculty of Public Health, Health Care and Tourism, National Sports Academy "Vassil Levski" - Sofia, Bulgaria

 

Abstract: Pulmonary rehabilitation is a complex program for patients mostly with chronic respiratory disorders. But it is also suitable for patients of different age after surgical interventions, cardiovascular, central and peripheral neurological diseases, etc. Respiratory physiotherapy is integrated into the overall treatment approach and is individually targeted to reduce the severity of respiratory complaints, optimize functional status, prevent complications from other organs and systems, reduce economic costs and the need for health care, and to maintain patients in a stable condition. It is a well-established and effective therapeutic strategy to reduce shortness of breath, improve exercise tolerance, and increase quality of life in combination with medical treatment.

Keywords: pulmonary rehabilitation, physiotherapy.

 

Pulmonary rehabilitation (PR) is a scientifically based, multidisciplinary, comprehensive program for patients, primarily with chronic pulmonary diseases (CPD). It is suitable for patients of different ages with respiratory disorders following surgical interventions, central and peripheral neurological diseases, cardiovascular and other diseases. Pulmonary rehabilitation is integrated into the overall approach to patient treatment and is individually directed toward reducing the severity of respiratory complaints, optimizing functional status, preventing complications involving other organs and systems, reducing economic costs and the need for healthcare services, and maintaining patients in a stable condition. PR is an established and effective therapeutic strategy for reducing dyspnea, improving physical tolerance, and enhancing quality of life in combination with medication therapy. Its long-term therapeutic goals include the maximum possible functional recovery of the patient and achieving greater independence in daily life. The maintenance of achieved results is aimed at reducing the need for healthcare services and the number of hospitalizations.

 

Pulmonary rehabilitation can be applied in clinical, outpatient, sanatorium, and home settings. Medical rehabilitation, as part of the general rehabilitation program for patients with CPD, includes not only kinesitherapy but also preformed physical factors, balneotherapy, and climatotherapy. Rehabilitation programs for patients with chronic pulmonary diseases are well established in practice to support standard therapy (medications, inhalations, oxygen therapy, surgical interventions, etc.) with a view to controlling, alleviating, and reducing subjective complaints and optimizing the functional capacity of patients to prevent their disability (ATS/ERS, 2006).

The primary goal of pulmonary rehabilitation is the maximum possible functional recovery of the patient in order to achieve greater independence in daily life. This goal is achieved by increasing patients’ physical activity, familiarizing them with the specific characteristics of their disease, treatment methods, and options for managing emergency conditions. A large number of rehabilitation strategies have been developed for treating patients with CPD. Rehabilitation programs usually include the following components: functional assessment of the patient, physical exercises, training in various breathing techniques and methods, educational lectures, discussions, films, printed materials, etc., rational dietary regimen, and psychosocial support. Pulmonary rehabilitation is suitable for all patients in stable clinical condition who have respiratory complaints. Although it can be applied both in the hospital and outpatient stages, almost all studies are conducted with outpatient patients.

 

The main objectives of Pulmonary Rehabilitation (PR) are the reduction of symptoms, improvement of quality of life, increase of motor activity in daily life, and enhancement of psycho-emotional tone. In patients with chronic lung diseases (CLD), a vicious cycle is present, as the feeling of shortness of breath, characteristic for a large portion of patients, leads to a reduction in overall physical activity. Hypokinesia is the cause of worsened physical condition, which deepens dyspnea and limits social contacts, leading to depressive states and further reducing the desire for physical effort.

The requirements, goals, and objectives of comprehensive PR are included in the statement of the American Thoracic Society and the European Respiratory Society (Nici L, 2006). A significant number of randomized clinical and multicenter studies exist, which prove the significant and long-term effect of applying PR and various methods and forms of kinesitherapy. The authors unanimously agree that no further evidence is needed that PR, in combination with bronchodilator therapy, provides significantly better results in patients with CLD than the use of standard medication therapy alone.

The main goal of future research should be: the type, duration, and content of PR, and especially the methodology of the kinesitherapy procedures conducted (Petkov Iv., 2008; Wijkstra P, 1995).

According to the studies of Troosters T et al. (2005), the results from PR increase peak work load by 18%, peak oxygen consumption by 11%, and endurance time by 87% compared to the baseline level. The distance covered in the six-minute walk test increases by 49 meters. Casaburi R et al. (2005) consider that PR has at least a proven additive effect in bronchodilator therapy with a long-acting anticholinergic medication.

Although further research is needed regarding the exact criteria for selecting suitable patients for inclusion in kinesitherapy (KT) programs, it is accepted that physical exercises positively affect patients with CLD in all stages of the disease, and the long-term effect of one KT course is undoubtedly proven (Griffiths T, 2000).

 

 

Comprehensive pulmonary rehabilitation includes four main components, namely: assessment of the patient’s condition, conduction of kinesitherapy procedures, education, and psychosocial support (GOLD, 2023).

1. Kinesitherapy(KT)

Physical tolerance is determined through ergometry or treadmill testing, while simultaneously taking into account a number of physiological indicators such as: maximum oxygen consumption, maximum heart rate, and maximum amount of work performed. Suitable for this purpose are the six-minute walk test (6 MWT) and the shuttle test (ISWT) (Singh S, 1992). The frequency of KT procedures varies among different authors – from daily sessions to once a week. The duration of a single KT session is between 10 – 45 minutes. The intensity ranges from 50% of peak oxygen consumption (low to moderate intensity) to the maximum possible, tolerated(high intensity)(Mahler D, 1998).

The optimal duration of a KT intervention is still a matter of discussion and debate, but fewer than 28 procedures have no significant effect on the condition of patients with COPD (Troosters T, 2005). Most often, a KT course is within 4 to 10 weeks (Lacasse Y, 2006).

To conduct an effective comprehensive KT program, at least 6 weeks are needed. Longer therapeutic courses have a better and more lasting effect (Green R, 2001). So far, no program has been developed that permanently maintains the achieved results (Ries A, 2007).

Many physicians advise patients to walk for at least 20 minutes daily if they are unable to participate in KT programs.

Other approaches are also being experimented with to improve the results of endurance training, such as pursed-lip breathing, the use of oxygen (Emtner M, 2003), or heliox (a mixture of helium and oxygen) during the performance of physical exercises (Palange P, 2004).

The inclusion of physical exercises for the upper limbs or strength exercises in addition to aerobic training leads to improved muscle strength, but does not change physical tolerance and quality of life (Young P, 1999).

The specific effect of the use of nutritional supplements, anabolic preparations, and neuromuscular stimulation is not well clarified (Lotters F, 2002).

Improvements after the application of kinesitherapy:

1. Kinesitherapy improves physical capacity, reduces dyspnea, improves quality of life, reduces the number of hospitalizations and hospital stay, improves mood, and reduces anxiety (Dimitrova, A., 2008).

2. The effect is maintained even after discontinuation of kinesitherapy sessions (ATS/ERS, 2006).

3. Training of the respiratory musculature is appropriate, especially in combination with general strengthening physical exercises (Petkov, I., 2009).

Kinesitherapy is successfully applied in patients in clinical stage, outpatient settings, and at home. Usually, the kinesitherapy procedures are group-based, between 6 and 8 people.

With regard to functional status, positive changes are established in patients from all stages of COPD, with various accompanying diseases. It is considered that patients with dyspnea rated 5 on the dyspnea scale (MRC) would respond with more difficulty to kinesitherapy (Wedzicha J, 1998).

The selection of highly motivated patients is decisive when conducting outpatient kinesitherapy procedures. Including current smokers in kinesitherapy programs may be appropriate in view of smoking cessation. However, smokers are more likely to drop out of kinesitherapy sessions compared to non-smokers (Young P, 1999).

 

 

 

1. Detailed anamnesis and physical examination.

2. Spirometry with and without bronchodilators.

3. Assessment of physical capacity.

4. Assessment of quality of life and the impact of dyspnea on it.

5. Examination of muscle strength of the inspiratory and expiratory respiratory musculature and of the m. quadriceps femoris.

 

2. Recommendations regarding the dietary regimen of patients with COPD 

 

A problem for patients with COPD is both overweight and underweight. Recommendations for an appropriate dietary regimen are based on several small randomized clinical trials (Nici L, 2006). About one quarter of patients in stages two, three, and four have a reduced body mass index and decreased fat tissue. The reduction of the body mass index is an independent risk factor for mortality in COPD. Patients who have difficulty breathing while eating are advised to eat more frequently and in small portions. Patients who increase the energy intake of the body also improve the strength of the respiratory musculature (Efthimiou J, 1988).

 

3. Education of patients with COPD

Most PR programs include elements of education, but the effect of their independent use without the application of kinesitherapy remains unclear. Main components in the education of patients and their relatives include encouragement and support for smoking cessation, information about the disease and ways of treatment, proper use of inhalers, strategies for managing shortness of breath, early recognition and treatment of exacerbations at home.

 

4. Very important is also the psychosocial support that patients and their relatives receive in order to cope with the disease (CTS, 2007).

Some basic physiological mechanisms of the effect of physical exercises on pulmonary function have been established. Thoracic and diaphragmatic breathing, rhythmic exercises for distal muscle groups, and isometric exercises in a circulatory mode lead to gradual adaptation of the cardiovascular and respiratory systems, as they reduce peripheral vascular resistance and improve peripheral and coronary circulation. Targeted breathing exercises (diaphragmatic breathing, vocal gymnastics, exhalation through pursed lips) assist respiratory re-education in patients with respiratory diseases. It is necessary for the application of therapeutic exercises to be from a suitable starting position in patients with COPD, in order to improve both static and dynamic respiratory indicators. It is known that their use in clinical and outpatient settings improves gas exchange, the function of respiratory muscles, pulmonary ventilation, motor capabilities, and the quality of life of patients. Breathing strategies include various techniques for relieving and improving breathing (Guncheva M., Iv. Petkov, 1982; Gosselink R., 2003). Accuracy and precision are required in the application of targeted breathing exercises in patients with pulmonary diseases.

Training in the correct execution of diaphragmatic breathing and its improvement is carried out through the unlocking of the diaphragm, which leads to a reduction in energy expenditure during breathing, supports pulmonary ventilation, and improves gas exchange. It helps to expel the residual air from the lungs during exhalation and improves the elasticity of the lung parenchyma. It also leads to a reduction in the respiratory rate and minute ventilation, as well as an increase in tidal volume. This effect is associated with the relief of dyspnea and the unloading of the accessory respiratory muscles during the breathing act by the active involvement of the diaphragm (Guncheva M., Iv. Petkov, 1990). The result of its application is better efficiency and economy of breathing, as it reduces the movement of the upper part of the chest (Troosters T, 2005).

By using exercises with exhalation through semi-open lips, bronchial spasm is prevented, respiratory rate and hypercapnia are reduced, and minute ventilation is increased. It has been found that in some patients this way of breathing occurs spontaneously. It also facilitates the involvement of the abdominal muscles and the upward lifting of the diaphragm. In this way, pulmonary gas exchange is improved with increased oxygen saturation of the blood. It also positively affects the disruption of pathological breathing patterns by increasing tidal volume, reducing respiratory rate, dyspnea, and static pulmonary hyperinflation, as objectively measured by optoelectronic plethysmography in patients with severe COPD (Marinov Bl., 2011). Several authors have proven that exhalation through slightly open lips is more effective in patients with COPD compared to spontaneous breathing. They justify the advisability of its application with its effect on prolonging expiration, reducing bronchospasm, respiratory rate, dyspnea, and partial pressure of carbon dioxide in the blood, as well as increasing tidal volume and partial pressure of oxygen in the blood at rest (Bianchi R, 2004). A relaxing massage of the shortened intercostal muscles is necessary to normalize muscle imbalance and muscle tone of the main inspiratory musculature, which also ensures their greater initial length.

Various exercises including trunk bends and tilts are used to improve the mobility of the spine and costovertebral joints and to reduce the rigidity of the chest. In this way, pulmonary function is also improved (Petkov I., 2008). 

Physical exercises increase the body’s oxygen demand, which is met by deepening and quickening of breathing and increased pulmonary perfusion. In healthy people, the reserves of the lungs that do not participate in breathing at rest are recruited. The tidal volume increases due to deeper inhalation. The elasticity of the lungs increases, which increases the speed of expiratory flow.

In patients with COPD, these adaptive mechanisms are impaired. Exhalation is prolonged and requires more time than in healthy individuals. The combination of loss of pulmonary elasticity, bronchial obstruction, and collapse of terminal bronchi complicates exhalation, and at rest, air becomes trapped in the lungs (static pulmonary hyperinflation). Breathing rate increases during physical activity, the time for exhalation decreases further, and the amount of trapped air increases – dynamic pulmonary hyperinflation. Pulmonary hyperinflation is objectively measured by spirometry through a decrease in inspiratory capacity, an increase in residual volume, and an increase in functional residual capacity after normal exhalation.

Kinesitherapy is a key factor for conducting a successful rehabilitation program. The challenge is to develop a kinesitherapy method that stimulates the cardiorespiratory system and skeletal muscles towards physiological changes that compensate for complications in COPD. A limiting factor for physical exertion in patients is the inability to adequately deliver oxygen to peripheral muscles due to ineffective gas exchange in the lungs. This is restricted by impaired pulmonary mechanics due to dynamic hyperinflation of the lungs and limited airflow. Conditions are created for the development of pulmonary hypertension during physical exertion (Barbera J, 2003).

Another limiting factor is impaired skeletal muscle function in a large proportion of patients. Every kinesitherapy (KT) program must be strictly individualized and adapted according to the condition of the cardiorespiratory system and the musculoskeletal apparatus. Skeletal muscle dysfunction is discussed in numerous review articles. Muscle hypotrophy and muscle weakness are negative prognostic factors. They require appropriate measures to overcome them, which are achieved through KT and represent an important prerequisite for the effect of pulmonary rehabilitation (PR). Skeletal muscle dysfunction is characterized by decreased muscle strength and endurance, increased fatigability, reduced oxidative enzyme capacity in muscle cells, a lowered threshold for lactate formation, a relative increase in the number of glycolytic type I muscle fibers, as well as increased ventilatory demands during physical exercise (Allaire J, 2004).

The specific causes of the observed muscle dysfunction are well elucidated. One is the sedentary lifestyle of the patients. The use of corticosteroids also leads to increased muscle weakness (Decramer M, 2008). Systemic chronic inflammation, oxidative stress, loss of body weight, and especially loss of fat-free mass are directly associated with skeletal muscle dysfunction in COPD (Troosters T, 2005).

Authors recommend the use of interval training, which reduces dynamic hyperinflation of the lungs during kinesitherapy procedures, especially in patients with severe COPD. The inclusion of resistance exercises for small muscle groups is advisable, as it reduces the ventilatory requirements of the body and peripheral vascular resistance. The best effect is achieved by combining them with endurance physical exercises. This improves the distance covered in the six-minute walk test (6MWT), quality of life, and reduces dyspnea (Casaburi R, 2004).

The reasons for the deteriorated quality of life are impaired function of the respiratory system and the overall functional state of other organs and systems. Systemic disorders manifest with muscle weakness, general fatigue, and changes in muscle metabolism, while impaired ventilation is associated with changes in breathing. Limited physical activity contributes significantly to the deteriorated quality of life in COPD. Hypokinesia is due to the increasing sensation of shortness of breath during physical effort initially with heavier, and later with lighter exertions. Dyspnea causes patients to rest and avoid movement, and thus hypokinesia deepens and leads to loss of muscle mass and reduction of body weight. In the terminal stage, patients are unable to self-care. In 2006, Lacasse Y et al. conducted an in-depth analysis of 31 randomized controlled studies and concluded that rehabilitation of patients with COPD is an important component of the overall treatment strategy for the disease. They report statistically and clinically significant improvements in quality of life regarding the sensation of shortness of breath, fatigue, emotional state, and disease control. In a meta-analysis by Cambach W et al. (1999), 18 articles were included which indicate significant improvements after pulmonary rehabilitation regarding physical capacity, endurance, walking, and all aspects of the specialized quality of life scale for COPD (Chronic Respiratory Disease Questionnaire – CRDQ), such as dyspnea, fatigue, emotions, and skills. The increased maximal physical capacity and distance walked within a given time are maintained above baseline values up to 9 months after completion of the rehabilitation procedures. The control, reduction, or elimination of dyspnea is also a result of applying pulmonary rehabilitation in patients with COPD (ACCP/AACVPR Pulmonary Rehabilitation Guidelines Panel, 2007).

The problems in carrying out activities for health promotion, disease prevention, and health protection are mainly related to the dominance of the therapeutic approach in the implementation of health policy and the insufficient application of the principles for the development of modern public health (Ivanova T., 2007; Popova S., 2004). Morbidity in COPD progressively increases with advancing age. The delay in its diagnosis is due to the unnoticed onset of the disease, the prolonged preclinical period, and the lack of serious complaints from patients. Usually, the diagnosis is made at a more advanced stage of the disease, when the patients’ age is also higher. Along with respiratory problems, negative changes occur in other organs and systems of the body. Based on this generalized age-related psychophysical decline, chronic respiratory failure develops and deepens.

Therefore, treatment, rehabilitation, and prevention of complications of COPD are closely related to reducing the adverse effects of the occurring age-related changes and improving the adaptation of the body under the influence of targeted physical activity (Petkov I., 1998).

According to the requirements of the World Physiotherapy organization (WPT) for ethical rules, standards, and competencies for the work of kinesiotherapists and the published guidelines for obtaining informed patient consent, it is advisable to prepare and sign voluntary informed consent for conducting kinesiotherapeutic procedures in patients with chronic pulmonary diseases (Ethical Code, 2005).

Pulmonary rehabilitation aims to solve main tasks related to improving the subjective condition regardless of the severity of the disease. It achieves control and reduction of respiratory symptoms – shortness of breath, cough, and expectoration. Respiratory rehabilitation focuses on improving functional capacity and endurance and increases tolerance to increasing physical exertion (Bulgarian Society of Pulmonary Diseases, 2012; Dimitrova A., 2013; GOLD, 2023).

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