Pulmonary Rehabilitation in Patients Undergoing Lung-Volume ...

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CARDIOPULMONARY REHABILITATION AND CANCER REHABILITATION: FOCUSED REVIEW

Pulmonary Rehabilitation in Patients Undergoing Lung-Volume Reduction Surgery Matthew N. Bartels, MD, MPH, Heakyung Kim, MD, Jonathan H. Whiteson, MD, Augusta S. Alba, MD ABSTRACT. Bartels MN, Kim H, Whiteson JH, Alba AS. Pulmonary rehabilitation in patients undergoing lung-volume reduction surgery. Arch Phys Med Rehabil 2006;87(3 Suppl 1):S84-8. Chronic obstructive pulmonary disease (COPD) is the most common form of primary pulmonary disability. Few effective treatment options exist for it, but recently, lung-volume reduction surgery (LVRS) has been shown to be effective in selected patients with emphysema. Pulmonary rehabilitation is an integral part of the preparation for and recovery from the procedure and has significant benefit in helping to improve the quality of life and conditioning of patients with COPD who undergo LVRS. Overall Article Objectives: (a) To describe the role of pulmonary rehabilitation in LVRS, (b) to understand the components of a comprehensive pulmonary rehabilitation program, and (c) to describe the effects of a pulmonary rehabilitation program. Key Words: Lung-volume reduction; Pulmonary disease, chronic obstructive; Quality of life; Rehabilitation. © 2006 by the American Academy of Physical Medicine and Rehabilitation MPHYSEMA HAS BEEN DESCRIBED in autopsy studies since the eighteenth century. The recognition of a E defect in deflation of the lungs was recognized early, and since then, the basic physiology of emphysema, including severe hyperinflation, airway obstruction, high residual volume, and poor lung elastic recoil have been described. Medical regimens, including bronchodilators and corticosteroids, have limited effect, especially in people with pure emphysema without reactive airway disease. Attempted surgical approaches to emphysema began in the early 20th century, but it was only in the later half of the century that the underlying pathophysiology of emphysema was understood well enough to allow better approaches. Only recently have the improvements in perioperative and intensive care management allowed surgery to be successful in this very ill group of patients.1 The goal of lung-volume reduction surgery (LVRS) is to improve the mechanics of ventilation by reducing residual volume, decreasing ventilation-perfusion mismatch, and improving lung elastic recoil. In appropriately selected patients

From the Rehabilitation Medicine Department, Columbia University, College of Physicians and Surgeons, New York, NY (Bartels); Pediatric Rehabilitation Medicine, The Children’s Hospital of Philadelphia, University of Pennsylvania Health System, Philadelphia, PA (Kim); and Rusk Institute of Rehabilitation Medicine, New York University School of Medicine, New York, NY (Whiteson, Alba). Supported in part by the Vidda Foundation. No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated. Reprint requests to Matthew N. Bartels, MD, MPH, Rehab Med Dept, 630 W 168th St, Unit #38, New York, NY 10032, e-mail: [email protected]. 0003-9993/06/8703S-10547$32.00/0 doi:10.1016/j.apmr.2005.12.013

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(eg, with apical disease, low-exercise capacity on cardiopulmonary exercise test, pure emphysema without bronchiectasis) the surgery can be done through either a median sternotomy or a video-assisted thoracoscopic approach. The operation removes the most involved lung parenchyma in the apices of the lungs, improving lung dynamics. As shown in the National Emphysema Treatment Trial (NETT),2 LVRS significantly improves both survival and quality of life (QOL). Both the NETT and the Global Initiative on Obstructive Lung Disease (GOLD) workshop3 identified rehabilitation as an essential part of the management of all forms of chronic obstructive lung disease (COPD). Rehabilitation for LVRS and COPD are similar, with pre-LVRS rehabilitation focusing on the specific surgical issues. PULMONARY REHABILITATION FOR SEVERE COPD COPD is the fourth highest cause of death in the United States, with the estimated national prevalence between 14 and 20 million people.4 It ranks second only to cardiac diseases in payments from Social Security disability. Most COPD is caused by cigarette smoking; 15% of all smokers will develop COPD.5 LVRS is an appropriate approach to treat this condition in selected patients, and pulmonary rehabilitation is an important part of treating this special population of patients. In COPD patients who are LVRS candidates, the NETT established pulmonary rehabilitation as essential.2,6,7 Rehabilitation’s focus is to maximize function, alleviate COPD’s physiologic effects, and decrease the psychosocial effects. Early mobilization programs to treat COPD are now accepted practice. The current definition of pulmonary rehabilitation was established at the consensus committee of the National Institutes of Health in 1994. The committee stated that “Pulmonary rehabilitation is a multidisciplinary continuum of services directed to persons with pulmonary disease and their families, usually by an interdisciplinary team of specialists, with the goal of achieving and maintaining the individual’s maximum level of independence and functioning in the community.”8(p826) Unfortunately, research in pulmonary rehabilitation is limited by the lack of clearly consistent data across trials and the lack of well-controlled longitudinal studies. However, the clinical consensus is that pulmonary rehabilitation is efficacious when comprehensive treatment is provided. In 1997, the American College of Chest Physicians (ACCP) and the American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR) released a joint ACCP/AACVPR statement of evidence-based guidelines supporting pulmonary rehabilitation,9 and the GOLD workshop has endorsed rehabilitation for COPD.3 BENEFITS OF PULMONARY REHABILITATION The main pulmonary rehabilitation goals for patients before LVRS are to increase function, improve QOL, and decrease dyspnea. Rehabilitation prepares patients both physically and psychologically for the challenging and difficult recovery after LVRS.

PULMONARY REHABILITATION FOR LVRS, Bartels

Exercise capacity is usually assessed with a 6- or 12-minute walk test or a symptom-limited exercise test with the determina˙ O2max). The walk test is tion of maximum oxygen consumption (V a submaximal exercise test, measuring the greatest sustained, comfortable effort in distance that the individual can perform. The walk test must be performed meticulously, because small changes in technique can alter results. Because the test measures efficiency of exercise, benefits from training will be observed by an increase in walking distance, with decreased dyspnea. The ˙ O2max test) evalsymptom-limited maximum exercise test (V uates the person’s maximum exercise capacity. There is a small ˙ O2max testing, and it risk of complications or death during V requires specialized training and equipment to perform. Still, for patients who are at high risk, for subjects in research trials, ˙ O2max results can be or for people scheduled for LVRS, V invaluable. One of the clearest benefits of pulmonary rehabilitation is decreased dyspnea. Multiple studies have shown a decrease in subjective dyspnea during activities of daily living (ADLs) and during exercise testing.10-12 With ongoing maintenance exercise, the benefit of decreased dyspnea can be sustained. Dyspnea may decrease because of 3 factors: (1) improved exercise performance with improved efficiency, (2) decreased ventilation with given activities, and (3) desensitization, with less subjective dyspnea for a given amount of ventilation.13,14 Although dyspnea measurement is qualitative, it is a clinical symptom that should be closely followed. Dyspnea scales are routinely used to quantify rehabilitation outcomes. QOL is a valuable measure in current medical research and improves after pulmonary rehabilitation in most studies of COPD.15-19 Commonly used scales for dyspnea and QOL are summarized in table 1. COMPONENTS OF AN LVRS PROGRAM Smoking Cessation Cigarette smoking is as addictive as alcohol or opiates,20 which explains people’s tendency to continue to smoke even in the face of pulmonary disease. Direct confrontation and persistence concerning abstinence are critical components in the management of LVRS patients. The cooperation of the referring physician is essential, because his/her counseling and warnings are important predictors of program compliance.21,22 Generally, people who start a pulmonary rehabilitation program should either have stopped smoking or have committed to cessation. The rehabilitation program then acts to support the initiation and continuation of smoking cessation, integrate smoking cessation with the rehabilitation program, and educate patients and families about maintaining a smoke-free environment.23 Education Education is essential to the pulmonary rehabilitation program, with the goals of medication compliance, appropriate oxygen use, lifestyle improvements, and increased physical capacities. The benefits of education include a decrease in hospitalizations and amelioration of exacerbations.24,25 Education alone is not as effective as education combined with an exercise rehabilitation program26,27 and must include both the patient and the family. Key educational components include attention to the following 7 issues. Energy conservation. The basic principle is that all activities must be as efficient as possible to preserve energy. A helpful analogy for COPD patients is to compare their energy

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state to a machine with limited battery storage. They have insufficient energy to achieve all tasks at full speed and must carefully consider how they will use the “charge” that is available to them. Through being more “energy smart,” they perform more than they thought possible. Coupled with exercise efficiency, energy conservation provides many of the benefits seen after pulmonary rehabilitation.28 Medications. Many patients do not fully understand the medications they are taking, often using their inhaled medications improperly.29 Education includes discussion of common medications with a review of mechanisms of action and side effects. Drug interactions are reviewed, with attention to overthe-counter medications (eg, the interaction of pseudoephedrine and albuterol). Technique instruction in the use of inhaled medications is often best done on an individual basis, whereas group education sessions can be used for the overall didactic portions of the program. Oxygen therapy. Oxygen therapy education is allied to medication education. Correctly used, oxygen can improve mortality in end-stage lung disease.30,31 Survival is improved by preventing pulmonary hypertension and polycythemia. Demonstration of oxygen equipment and safety education is performed in individual settings and reinforced in group didactic sessions to ensure a complete understanding. Oxygen titration during exercise and activity must be determined on an individual basis. Subjects should keep their hemoglobin-oxygen saturation well above 85% or maintain an arterial oxygen level of at least 60mmHg, because this is on the shoulder of the steep portion of the hemoglobin-oxygen saturation curve. Nutritional counseling. Either a nutritionist or another team member can perform counseling,32,33 ranging from group education to intensive individual intervention. Focus is on meeting the unique needs of the presurgical patient with COPD who has an increased basal metabolic demand34 with lower lean body mass causing lower functional capacity35,36 and decreased survival.37 A higher fat and protein diet is appropriate in COPD because the metabolism of these nutrients yields a lower carbon dioxide load per unit of energy. Disease-specific education. Disease-specific didactic education can be provided with a series of handouts that can be placed into a loose-leaf binder and updated during the pulmonary rehabilitation program.9,38 Stress management. Although stress management alone does not significantly alter the course or prognosis of COPD, it can improve a patient’s function, possibly by allowing better coping with the disease.39,40 Pulmonary toilet. Secretion management techniques, including aspects of chest physical therapy, should be taught preoperatively. These include percussion, postural drainage, suctioning, and insufflation and exsufflation as appropriate.41,42 Respiratory muscle strengthening and endurance training may be indicated on an individual basis.43 Issues Specific to LVRS Patients There are 4 phases of rehabilitation for people undergoing LVRS: preoperative, perioperative, postoperative, and maintenance. Each phase has specific goals, and previous training can be reinforced in subsequent phases.44 Preoperative rehabilitation. Ideally, presurgical patients should complete a comprehensive outpatient rehabilitation program. A comprehensive set of printed guidelines and a specific program schedule are important, with a 3-times-a-week program providing sufficient interaction. The team should include physical therapists, respiratory therapists, or nurses, directed by a rehabilitation medical director. Close contact must be mainArch Phys Med Rehabil Vol 87, Suppl 1, March 2006

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PULMONARY REHABILITATION FOR LVRS, Bartels Table 1: Dyspnea and QOL Instruments Instrument

Observation

Validity

Specifics

High for dyspnea Correlates with pulmonary function High for dyspnea Correlates with pulmonary function Valid for dyspnea Correlates with Chronic Respiratory Disease Questionnaire Fair repeatability

Classic scale: 6 –20 Modified Borg scale: 0 –10 Vertical analog scale: 100cm length Correlates with Borg scale Interview administered Focus is dyspneic activity Measures 3 components: (1) Functional impairment (2) Magnitude of effort (3) Magnitude of task Interview-based 20-item test Evaluates 5 usual activities Measures 4 dimensions: (1) Dyspnea (2) Fatigue (3) Emotional function (4) Mastery of breathing Self-administered questionnaire with 53 questions Measures 3 areas: (1) Symptoms (2) Activity (3) Impact on ADLs Self-administered questionnaire Evaluates 79 activities Has 6 categories of activities: (1) Self-care (2) Mobility (3) Eating (4) Home management (5) Social (6) Recreational 6-point scale 21 areas of ADLs Has 3 questions: (1) Shortness of breath (2) Fear of harm from overexertion (3) Fear of shortness of breath 30-min self-administered Covers many areas of function: (1) Social (2) ADLs (3) Mobility (4) Vocational (5) Communication (6) Cognition (7) Hygiene (8) Emotional status 15-min interviewer administered Covers multiple areas: (1) Mobility (2) Social (3) Symptoms (4) Physical activity 10-min self-administered Covers functions: (1) Role functioning (2) Pain (3) Health (4) Vitality (5) Social (6) Mental health

Borg scale of perceived breathlessness Visual analog scale

Direct

Baseline and transitional Dyspnea Index

Indirect

Chronic Respiratory Disease Questionnaire

Indirect

Good clinical validity for dyspnea Individualized dyspnea scale makes comparisons difficult

St. George’s Respiratory Questionnaire

Indirect

Good for QOL Fair for dyspnea Good reliability Good clinical correlation

Pulmonary Functional Status and Dyspnea Questionnaire

Indirect

Good for QOL Fair for dyspnea Good reliability Good clinical correlation

University of California, San Diego Shortness of Breath Questionnaire

Indirect

Newer instrument Fair repeatability

Sickness Impact Profile

General

Good validity Multiple domains Not disease specific

Quality of Well-Being

General


Medical Outcomes Study 36-Item Short-Form Health Survey

General


Direct



tained with the primary physician to ensure the referring physician’s support and coordination of medical management. Support groups allow patients to continue the lifelong program of pulmonary health management and enable team members to present special lectures on areas of interest. Social events can help minimize the isolation of patients. Pre-LVRS groups focus on familiarizing patients with the procedure and preparing them for the perioperative period. Topics include secretion mobilization, familiarization with postoperative mobilization, and introduction to the perioperative physical therapy staff. The preoperative rehabilitation program design has 3 main features: (1) patient screening, (2) exercise testing, and (3) an individualized presurgery exercise prescription. During patient screening, candidates for LVRS are identified on a team basis with regularly held conferences with the surgical and medical staff. All LVRS candidates must undergo pulmonary rehabilitation with an emphasis on education. The exercise testing consists of a symptom-limited maximal cardiopulmonary exercise test with expired gas analysis. It is performed on all subjects before they begin exercise training to tailor a presurgical exercise program that is performed at 60% of each person’s maximum exercise capacity. The peak wattage achieved on this test also determines each person’s surgical risk classification.2 The preoperative exercise prescription has 4 parts: (1) diagnosis of COPD, the plan for LVRS, and any other pertinent diagnoses; (2) a prescription specific to each patient, detailing a rehabilitation program that includes the educational, psychosocial, and nutritional needs of the patient. The exercise portion must specify both upper- and lowerextremity exercises, including strengthening and conditioning exercises, oxygen needs, intensity, duration, and program goals. It also should specify educational components that teach about LVRS to allay each patient’s anxieties and to adequately prepare him/her for the operation and individual psychosocial interventions to address depression and anxiety; (3) an exercise frequency and duration note thrice weekly, which is recommended for 6 to 8 weeks for a total of 18 to 24 sessions; and (4) precautions, in which heart rate and blood pressure parameters, oxygen limits, and safety parameters must be specified. Perioperative rehabilitation program. The perioperative program involves rapid mobilization. The goal is to be out of bed to a chair the first day, with ambulation started as soon as possible, and to be independent in all basic ADLs and household ambulation by discharge. The mobilization program should have 2 sessions a day, 7 days a week to maximize recovery. Close oxygen saturation monitoring is essential with telemetric monitoring as needed. Ideally, the interval from surgery to discharge is 5 to 7 days. About a third of patients require an inpatient acute rehabilitation stay because of complications or severe debility. Chest physical therapy and pulmonary toilet should be aggressive, but the time devoted to pulmonary toilet should not detract from the time spent on patient mobilization. Postoperative rehabilitation program. Although most patients go home right after surgery, some patients may require inpatient rehabilitation or prolonged ventilator weaning before returning home because of postoperative complications. Regardless, all patients resume their preoperative outpatient program rapidly after discharge. Home-based rehabilitation should be a brief transition to the outpatient program. The require-

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ments of the outpatient program are essentially the same as those for the preoperative phase. The exercise program is done once or twice a week. Maintenance. After completion of postoperative rehabilitation, ongoing support from family, the primary care physician, and other support groups is essential to create an environment that encourages exercise compliance. Support groups are useful, allowing current patients to meet graduates of the program. Compliance is increased when patients have access to wellness centers. These centers allow former patients to come and exercise in the rehabilitation setting for a nominal fee with a lower level of supervision.45 CONCLUSIONS Pulmonary rehabilitation for COPD aims to maximize patients’ QOL and functional ability. For patients undergoing LVRS, rehabilitation plays an important role in both the presurgical preparation and postoperative recovery. The combination of pulmonary rehabilitation and LVRS provides the greatest benefit for selected patients with severe emphysema, well above the effects of either intervention alone.46 Research is needed to define the exact contributions of pulmonary rehabilitation in other forms of lung disease and for other pulmonary surgical interventions. Preoperative and postoperative rehabilitation is required for LVRS surgery because of the benefits it bestows. Maximal pulmonary rehabilitation before surgery prepares the patient for the procedure, improves conditioning, and decreases complications. Aggressive perioperative rehabilitation prevents complications. Postoperative rehabilitation allows the maximum benefit to be realized from LVRS. References 1. DeRose JJ, Steinglass KM. The history of surgery for emphysema. In: Argenziano M, Ginsburg ME, editors. Lung volume reduction surgery. Totowa: Humana Pr; 2002. p 127-37. 2. Fishman A, Martinez F, Naunheim K, et al. A randomized trial comparing lung-volume-reduction surgery with medical therapy for severe emphysema. New Engl J Med 2003;348:2059-73. 3. Pauwels RA, Buist AS, Calverley PM, Jenkins CR, Hurd SS, GOLD Scientific Committee. Global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease. NHLBI/WHO Global Initiative for Chronic Obstructive Lung Disease (GOLD) Workshop summary. Am J Respir Crit Care Med 2001;163:1256-76. 4. Celli BR, Snider GL, Heffner J, et al. Standards for the diagnosis and care of patients with COPD. Am J Respir Crit Care Med 1995;152(Suppl 5):S78-121. 5. Petty TL. The worldwide epidemiology of chronic obstructive pulmonary disease. Curr Opin Pulm Med 1996;2:84-9. 6. National Emphysema Treatment Trial Research Group. Rationale and design of the National Emphysema Treatment Trial: a prospective randomized trial of lung volume reduction surgery. Chest 1999;116:1750-61. 7. National Emphysema Treatment Trial Research Group. Rationale and design of the National Emphysema Treatment Trial: a prospective randomized trial of lung volume reduction surgery. J Cardiopulm Rehabil 2000;20:24-36. 8. Fishman AP. Pulmonary rehabilitation research. Am J Respir Crit Care Med 1994;149(3 Pt 1):825-33. 9. Working Group of the South African Pulmonology Society. Guidelines for the management of chronic obstructive pulmonary disease. South Afr Med J 1998;88:999-1002, 1004, 1006-10. 10. Reardon J, Awad E, Normandin E, Vale F, Clark B, ZuWallack RL. The effect of comprehensive outpatient pulmonary rehabilitation on dyspnea. Chest 1994;105:1046-52. Arch Phys Med Rehabil Vol 87, Suppl 1, March 2006

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