Introduction

Pulmonary rehabilitation is ‘an evidence-based, multidisciplinary and comprehensive intervention for patients with chronic respiratory diseases who are symptomatic and often have decreased daily life activities’.1 Pulmonary rehabilitation has been used for decades, but its acceptance has only recently become widespread. In part, this is due to the experience with lung volume reduction surgery (LVRS) for chronic obstructive pulmonary disease (COPD). In the National Emphysema Treatment Trial (NETT), pulmonary rehabilitation was a component of standard therapy for patients undergoing surgery. In a review of the experience of NETT patients in pulmonary rehabilitation, in addition to demonstrating the efficacy of LVRS in a subset of patients with severe emphysema, it showed that widespread use of pulmonary rehabilitation resulted in substantial benefit for patients with COPD.2 This was the first study to demonstrate the efficacy of pulmonary rehabilitation across a large number of sites. Based on this, pulmonary rehabilitation has become standard of care both before and after LVRS. In addition, patients must participate in pulmonary rehabilitation both before and after lung transplantation.

Pulmonary rehabilitation has been slow to gain acceptance. It has never been shown to improve survival in patients with COPD. In addition, no consistent improvement in lung function has been demonstrated and oxygenation does not improve with pulmonary rehabilitation. Unfortunately, in the past, many practitioners interpreted these results as indicating that pulmonary rehabilitation was not beneficial. This was a result of a misconception about the goals of pulmonary rehabilitation. Patients with chronic lung disease suffer from chronic dyspnea, which leads to a reduction in daily activities and increased social isolation. This can contribute to the development of mood disturbances, which are very common in patients with COPD. When these outcomes are studied, the benefits of pulmonary rehabilitation become clear. Multiple studies of pulmonary rehabilitation have demonstrated significant improvements in exercise tolerance, endurance, symptoms of dyspnea, psychosocial well-being and quality of life, all of which are meaningful endpoints for patients suffering from this chronic disease. Awareness of pulmonary rehabilitation varies by region and even from practitioner to practitioner in a given area. In the USA, the Centers for Medicare and Medicaid Services recently granted a procedure code and national coverage determination for pulmonary rehabilitation. This has also raised awareness of pulmonary rehabilitation, partly as a business opportunity, but has also validated the hard work of many professionals who have advocated the benefits of this treatment modality.

Organization

There are no specific guidelines for the organization or structure of a pulmonary rehabilitation programme. A multidisciplinary approach is required with involvement from nursing, physical therapy, occupational therapy and respiratory therapy. Psychologists or social workers may also be employed, in addition to nutritionists and recreational therapists. A physician serves as the medical director. The medical director’s role includes performing the initial screening, writing the exercise prescription and monitoring the patients’ progress through the programme. The director is also available for emergency situations. The director acts as an educator to the staff and patients and may also be a research coordinator. One member of the team serves as the programme director and is responsible for the day-to-day management of the programme, recruitment and marketing.

The location of the programme varies. Although it is most often based in the outpatient setting as either a hospital-based or free-standing facility, it can also be performed in an inpatient setting or even at the patient’s home. A typical programme lasts for 8–12 weeks with 2 h sessions performed two to three times per week. Components of a pulmonary rehabilitation programme include exercise, education and psychosocial support.

Patient Selection

In general, patients with symptomatic chronic lung disease are likely to benefit from pulmonary rehabilitation. It was initially developed for patients with COPD over 30 years ago and much of the literature on the effects of pulmonary rehabilitation is based on its effect in this patient population. Recently, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classified COPD into four stages, depending on the magnitude of reduction in the forced expiratory volume in 1 s (FEV1).3 Patients with GOLD class II–IV [FEV1 <80% of predicted with a forced vital capacity (FVC) to FEV1 ratio of less than 70%] are eligible to participate in pulmonary rehabilitation.

The prevalence of COPD increases steadily with age. It is difficult to get an accurate estimate of COPD prevalence in the elderly because the FEV1/FVC ratio declines with age. As a result, some elderly normal patients may be classified as having COPD by the GOLD criteria. The National Center for Health Statistics in the USA estimated the incidence of COPD in elderly adults at just less than 10%.4 Rates in other countries may vary and many other factors may contribute to prevalence rates. For example, in China, prevalence rates increase significantly with age with 2.3% of those aged 40–49 years meeting the spirometric definition of COPD, whereas in those over 70 years of age the prevalence was 20.4%.5 Urban versus rural location, body mass index, level of education and amount of ventilation in a person’s kitchen also affected prevalence rates.

Not surprisingly, elderly patients with COPD comprise the majority of patients participating in most pulmonary rehabilitation programmes. In recent years, there has been increased interest in extending pulmonary rehabilitation to patients with other respiratory conditions. These patients also suffer from deconditioning, dyspnea, impaired health status and quality of life. Pulmonary rehabilitation has been used in patients with restrictive and interstitial lung diseases, bronchiectasis, asthma, chest wall disorders and pulmonary hypertension.6–9

Historically, pulmonary hypertension has been considered a contraindication to pulmonary hypertension. With exercise, especially static, resistive exercise, there is a significant increase in right and left ventricular overload. In patients with pulmonary hypertension, due to fixed pulmonary vascular constriction, this may lead to a dramatic rise in pulmonary arterial pressure without a rise in cardiac output, which may lead to circulatory failure. Recent experience has not supported this notion. Many patients with pulmonary hypertension related to other chronic pulmonary conditions (World Health Organization group III) exercise in pulmonary rehabilitation without complication. Furthermore, with the advent of numerous advanced therapies for pulmonary arterial hypertension (World Health Organization group I), it seems that these patients may exercise safely at submaximal exercise levels.

Owing to the increased utilization and literature now supporting the use of pulmonary rehabilitation for other chronic respiratory conditions, the latest version of the American College of Chest Physicians and American Association of Cardiovascular and Pulmonary Rehabilitation (ACCP/AACVPR) practice guidelines for pulmonary rehabilitation state that ‘pulmonary rehabilitation is appropriate for any stable patient with a chronic lung disease who is disabled by respiratory symptoms’.10