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At least 469 records · Page 26Linked to original sources

PubMed2005

Factors determining self-efficacy in chronic obstructive pulmonary disease.

OBJECTIVE: We investigated the factors determining self-efficacy in patients with chronic obstructive pulmonary disease (COPD). METHODS: Thirty male patients with COPD and 30 healthy controls participated in the study. Pulmonary function tests, 6-minute walk test (6MWT), modified Borg scale, modified Medical Research Council (MRC) dyspnea scale, Hospital Anxiety and Depression Scale (HADS), Activities of Daily Living Questionnaire (ADL-Q), and COPD Self-Efficacy Scale (CSES) were used for the evaluation. The study was performed between September 2003 and May 2004 at the Department of Chest Medicine, School of Physical Therapy and Rehabilitation, Hacettepe University, Ankara, Turkey. RESULTS: The COPD patients expressed higher depression and dyspnea level and impaired activities of daily living than healthy controls (p<0.05). Duration of disease and the ADL-Q score was significantly correlated with all subscales of CSES (p<0.05). Borg score and anxiety score were significantly related with negative affect, weather/environment, and behavioral risk factors subscales of CSES (p<0.05). Lung function was significantly related with physical exertion and behavioral risk factors, and 6MWT distance was significantly correlated with weather/environment and behavioral risk factors subscales (p<0.05). The MRC score was correlated with weather/environment score (p<0.05). The ADL-Q score and disease duration accounted for 76% of the variance in self-efficacy (p<0.05) CONCLUSION: Level of impaired activities of daily living due to respiratory limitation and the number of years since diagnosis are independent variables that predict self-efficacy, or level of confidence in engaging specific behaviors that lead to specific desired outcomes in COPD.

Activities of Daily Living↗

PubMedDate not supplied

Questioning the use of heart rate and dyspnea in the prescription of exercise in subjects with chronic obstructive pulmonary disease.

PURPOSE: This study examined the heart rate and dyspnea responses during constant submaximal lower limb endurance exercise in subjects with chronic obstructive pulmonary disease (COPD) to determine the appropriateness of using target heart rate or dyspnea for the prescription of endurance exercise intensity. METHODS: The study participants were 15 men, ages 55 to 75 years, with stable moderate to severe COPD (forced expiratory volume in 1 second, 38.7 +/- 15.6% pred). All the participants completed the incremental shuttle walking test (ISWT) to estimate peak oxygen consumption (VO(2peak)), followed by the endurance shuttle walking test (ESWT) at an intensity equivalent to 60% VO(2peak). Heart rate and dyspnea were monitored before, immediately after, and at 1-minute intervals during each test. RESULTS: The study was completed by 11 subjects. Heart rate and dyspnea increased significantly between 4.5 and 20 minutes during the ESWT (P <.01) despite walking at a constant submaximal workload. Heart rate and dyspnea attained at the end of the ESWT exceeded levels observed during the ISWT at the equivalent workload (P <.05). Four subjects were unable to walk for at least 10 minutes on the ESWT because of severe dyspnea and were withdrawn. CONCLUSIONS: Setting heart rate and dyspnea targets for endurance training at an intensity equivalent to 60% VO(2peak) may be inappropriate for subjects with moderate to severe COPD because heart rate and dyspnea increase independently of workload at this intensity.

Aged↗

PubMed2004

[Correlation between evolution of the cognitive function and mortality after hospital discharge in elderly patients with advanced heart failure].

OBJECTIVE: To assess the relation between the evolution of cognitive performance and the prognosis of elderly patients after compensation of advanced heart failure. METHODS: Thirty-one patients older than 64 (68 +/- 7) years and admitted with New York Heart Association class IV heart failure and ejection fraction = 0.45 (0.38 +/- 0.06) were consecutively selected. They underwent cognitive tests (digit span, digit symbol, letter cancellation, trail making A and B) and the 6-minute walking test 4 days before (T1) and 6 weeks after (T2) hospital discharge, and their performances were compared using the t test. The prognostic value of the scores of the cognitive tests was analyzed with logistic regression, and the value of greatest accuracy of the tests was associated with the prognosis determined by the ROC curve. RESULTS: After 24.7 months, 17 (55%) patients had died. The performances in the 6-minute walking test and most cognitive tests improved between T1 and T2. The digit span score of the survivors ranged from 3.9 to 5.2 (P=0.003) and remained unaltered among those who died (4.1 to 3.9; P=0.496). An improvement < 0.75 points in the score was associated with mortality (relative risk of 8.1; P=0.011). CONCLUSION: In the elderly, after compensation of advanced heart failure, the lack of evolutionary improvement in cognitive performance was associated with a worse prognosis.

Aged↗

PubMed1999

The effects of high-intensity and low-intensity cycle ergometry in older adults with knee osteoarthritis.

BACKGROUND: People with osteoarthritis (OA) of the knee experience pain and deconditioning that lead to disability. This study challenged the clinical belief that repetitive lower extremity exercise is not indicated in persons with knee OA. The effects of high-intensity and low-intensity stationary cycling on functional status, gait, overall and acute pain, and aerobic capacity were examined. METHODS: Thirty-nine adults (71+/-6.9 years old) with complaints of knee pain and diagnosis of OA were randomized to either a high-intensity (70% heart rate reserve [HRR]) or low-intensity (40% HRR) exercise group for 10 weeks of stationary cycling. Participants cycled for 25 minutes, 3 times per week. Before and after the exercise intervention they completed the Arthritis Impact Measurement Scale 2 for overall pain assessment, underwent timed chair rise, 6-minute walk test, gait, and graded exercise treadmill tests. Acute pain was reported daily with a visual analog scale and the Western Ontario and McMaster Universities Osteoarthritis Index scale. RESULTS: Analysis of variance revealed that participants in both groups significantly improved in the timed chair rise, in the 6-minute walk test, in the range of walking speeds, in the amount of overall pain relief, and in aerobic capacity. No differences between groups were found. Daily pain reports suggested that cycling did not increase acute pain in either group. CONCLUSIONS: Cycling may be considered as an alternative exercise modality for patients with knee OA. Low-intensity cycling was as effective as high-intensity cycling in improving function and gait, decreasing pain, and increasing aerobic capacity.

Activities of Daily Living↗

PubMed2003

Bosentan treatment in patients with primary pulmonary hypertension receiving nonparenteral prostanoids.

Primary pulmonary hypertension (PPH) is a life-threatening disease. Nonparenteral prostanoids, i.e. aerosolised iloprost or oral beraprost sodium show beneficial therapeutic effects but are not sufficiently active in all patients with this devastating disease. The purpose of the present study was to determine whether the endothelin-receptor antagonist bosentan is safe and effective in patients with PPH already receiving nonparenteral prostanoids. The effect of bosentan as add-on medication was studied in 20 patients with PPH, who received either inhaled iloprost (n=9) or oral beraprost (n=11) for a median period of 16+/-13 months, by means of the 6-min walk test and cardiopulmonary exercise testing. After 3 months of administration of bosentan in addition to prostanoids, the walking distance in the 6-min walk test increased by 58+/-43 m. Cardiopulmonary exercise testing revealed an increase in maximal oxygen consumption from 11.0+/-2.3 to 13.8+/-3.6 mL x kg(-1) x min(-1) accompanied by significant improvements in anaerobic threshold, oxygen pulse and minute ventilation/carbon dioxide production slope. Peak systolic blood pressure increased from 120+/-17 to 139+/-21 mmHg. Combination treatment was well tolerated by all patients. It is concluded that the addition of the endothelin-receptor antagonist bosentan to inhaled iloprost or oral beraprost therapy appears to be safe for patients with primary pulmonary hypertension, resulting in a marked increase in exercise capacity. Therefore, rigorous studies should address whether combination treatment is more effective than either therapeutic intervention alone.

Administration, Inhalation↗

PubMedDate not supplied

[Sildenafil in the management of idiopathic pulmonary arterial hypertension in children and adolescents].

OBJECTIVE: This study aims to provide data on the use of oral sildenafil in patients in New York Heart Association functional class III or IV with severe idiopathic pulmonary arterial hypertension unresponsive to conventional therapy. METHOD: In this series, six patients with idiopathic pulmonary arterial hypertension were prospectively treated with 2 to 8 mg of oral sildenafil in four to six doses a day. All patients were submitted to physical examination, electrocardiogram and echocardiogram, chest computed tomography, ventilation and pulmonary perfusion scintigraphy, coagulation studies, and tests for collagen vascular disease, acquired immune deficiency syndrome and schistosomiasis in order to rule out secondary causes of pulmonary arterial hypertension. All patients underwent cardiac catheterization for vasoreactivity tests using nitric oxide, O2 at 100% and oral nifedipine, and a 6 minute walking test was performed in those patients who were considered able to exercise. RESULTS: All patients achieved a good therapeutic response, with improvement by at least one functional class, and presented an increase in systemic arterial oxygen saturation. Five patients showed a decrease in the pulmonary systolic pressure to systemic systolic pressure ratio and improvement in the six-minute walking test. No major side effects were observed at 4 to 36 months of follow-up. One patient had sudden death after sildenafil had been withdrawn by mistake. CONCLUSIONS: These data suggest that sildenafil may be useful in the management of idiopathic pulmonary arterial hypertension. Patients should be advised against the withdrawal of sildenafil without medical supervision.

Administration, Oral↗

PubMed1998

Timing and priorities for cystic fibrosis patients candidates to lung transplantation.

Bilateral lung transplantation is actually considered a valuable option for patients with endstage lung disease related to cystic fibrosis. Timing is crucial to transplant successfully as many patients as possible and it is mainly based on the progressive worsening of pulmonary function tests and quality of life. We reviewed the charts of all patients accepted for lung transplantation at our institution, in order to assess the role of several functional and demographic parameters; we compared the group of patients able to successfully wait for transplantation (Group A) with patients dying on the waiting list (Group B). Twenty-eight patients were accepted: 15 were successfully transplanted (2 at other institutions) (mean waiting time: 117 days), 7 died waiting (mean waiting time: 108 days) and 6 are still on the list. We recorded FEV-1, FVC, PaO2, PaCO2, supplemental O2 requirement, 6-minute walking test, right ventricular ejection fraction (RVEF) and cardio-pulmonary hemodynamics measured at right heart catheterization; we recorded also age at time of diagnosis and at time of evaluation, sex, weight and Schwachman score. These parameters were compared between Group A and B. Age at time of evaluation, sex, weight and Schwachman score did not present any difference between the two groups, as well as pulmonary function tests, PaO2, 6-minute walk test and RVEF. A statistically significant difference was found in terms of PaCO2 (43.9 +/- 9.3 in Group A vs 69.1 +/- 32.4 in Group B, heart rate at rest (102 +/- 21 vs 131 +/- 12) mean pulmonary artery pressure (20.6 +/- 2.9 vs 36 +/- 15.7), pulmonary vascular resistances (350 +/- 96 vs 460 +/- 119.4), cardiac index (3.2 +/- 0.6 vs 5.4 +/- 0.9). On the base of our initial experience we conclude that a careful evaluation of CF candidates for lung transplantation is recommended. A deterioration of pulmonary function tests and quality of life are useful parameters to accept patients in the waiting list; however priority should be attributed also on the base of cardio-pulmonary hemodynamics. A larger series of patients is required to draw definitive conclusions.

Adult↗

PubMed2005

Short term and long term detraining: is there any difference between young-old and old people?

OBJECTIVES: To assess the effects of short (six weeks) and long (52 weeks) term detraining on functional fitness in elderly people, and to determine whether these effects differ according to age in elderly people. METHODS: Elderly subjects, aged 60-86 years, completed a nine week multicomponent exercise training programme. They performed the senior fitness test after six and 52 weeks, and the responses of 12 young-old subjects (YO, aged 60-73 years) and nine older subjects (O, aged 74-86 years) were compared. RESULTS: Functional fitness improved during the exercise training period. Short term detraining caused a loss of this improvement in functional performance. Performance on the chair stand test for both YO and O groups and on the up and go and six minute walk tests for the YO group remained significantly higher than before training after six weeks of detraining (p<0.013). Performance in all tests reverted to the pre-training values or lower after 52 weeks of detraining in both groups. In the O group, performances in the six minute walk test and arm curl test were lower than before training (p<0.013). The components of functional fitness most affected by detraining were agility with short term detraining, and aerobic endurance and upper extremity strength with long term detraining. CONCLUSION: Changes in functional capacity after short and long term detraining are affected by age in elderly adults.

Activities of Daily Living↗

PubMed2004

Stepping over obstacles to improve walking in individuals with poststroke hemiplegia.

For this study, we evaluated two training interventions for improving gait parameters in individuals with poststroke hemiplegia using a training methodology that required them to step over objects. Gait velocity, step length, ability to step over obstacles, and walking endurance were compared before and after 2 weeks of training and 2 weeks after cessation of training. Twenty subjects with poststroke hemiplegia completed six intervention sessions in which they were asked to step over either virtual objects while walking on a motorized treadmill or real foam objects on a 10 m walkway. With the virtual object training, if either foot collided with the virtual object, a tone sounded and a vibrotactile stimulus was applied to the colliding foot. All subjects tolerated the training sessions well, and no incidences of falling or undue cardiovascular responses occurred. The virtual obstacle training generated greater improvements in gait velocity compared with real training (20.5% vs. 12.2% improvement) during the fast walk test (p < 0.01). Improvements in gait velocity for both training methods were similar in the self-selected walk test (33.3% vs. 34.7% improvement). Overall, subjects showed clinically meaningful changes in gait velocity, stride length, walking endurance, and obstacle clearance capacity as a result of either training method. These changes persisted for 2 weeks posttraining. The inclusion of enhanced safety and visual augmentation may be responsible for the effectiveness of the virtual object intervention. These results demonstrate preliminary evidence for clinical effectiveness of obstacle training for improving gait velocity poststroke. In addition, these results provide evidence for enhanced clinical performance with virtual obstacle training.

Adult↗

PubMed2001

A new device for the measurement of disease severity in patients with intermittent claudication.

OBJECTIVES: To assess a new method of determining functional impairment in patients with intermittent claudication, the Double Physiological Walking Test (DPWT) using the PADHOC (Peripheral Arterial Disease Holter Control) device, against a standard treadmill test. DESIGN: Patients with intermittent claudication presenting to the department were considered for both the DPWT and a standard treadmill test. METHODS: initial claudicating distance, maximal walking distance and speed of walking were determined for both parts of the DPWT. Initial claudicating distance and maximal walking distance were determined from the treadmill test. Comparisons were made between the treadmill test and the DPWT. RESULTS: The treadmill test was unable to be performed in 22% of patients due to defined contraindications. There were strong correlations in both walking distances and disease severity when comparing the DPWT and the treadmill test. Patients in whom the treadmill test was contraindicated had significantly shorter walking distances on the DPWT than those who were able to complete a treadmill walking test. CONCLUSIONS: The DPWT correlates strongly with walking distances obtained from a standard treadmill test. However, the PADHOC can be used in a number of differing locations and settings as well as in patients in whom a treadmill test is contraindicated. It therefore has a role to play in the initial assessment of patients presenting with intermittent claudication.

Aged↗

PubMed2005

Cognitive functions in severe congestive heart failure before and after an exercise training program.

BACKGROUND: Congestive heart failure is associated with cognitive impairment, particularly of attentional skills. We assessed, in a hypothesis-generating study, the effect of an exercise training program on cognitive functions among patients with severe congestive heart failure. METHODS: Patients with severe congestive heart failure (n=20; New York Heart Association functional class III; left ventricular ejection fraction < or =35%) were evaluated before and following a standardized and supervised exercise training program (x2/week for 18 weeks; exercise group), while 5 additional patients did not undergo an exercise training program (control group). A battery of cognitive tests was used to assess cognitive functions. Physical performance was assessed by the 6-min walk test and the modified Bruce exercise test, cardiac index and systemic vascular resistance using thoracic electrical bioimpedance, and cerebral vasomotor reactivity to hypercapnia by means of the breath-holding index using transcranial Doppler. RESULTS: Time of completion of the trail making A (105+/-116 to 75+/-52; p=0.02) and B (169+/-100 to 119+/-65; p=0.002) tests, and of the Stroop part A (40+/-13 to 37+/-13; p=0.04) was shorter in patients completing the exercise training program, but not in control patients, while the other neuropsychological measures remained unchanged in both groups. Cerebral vasomotor reactivity to hypercapnia remained diminished (breath-holding index 0.64+/-0.27 vs. 0.68+/-0.37) despite significant improvements in exercise capacity (6-min walk test 308+/-87 to 423+/-91 m, p<0.001; modified Bruce exercise test 5.6+/-3.8 to 9.8+/-3.4 min, p<0.001). CONCLUSIONS: Patients with severe congestive heart failure undergoing an exercise training program improve in some measures of cognitive functions that are limited to general attention and psychomotor speed. Based on these preliminary findings, further evaluations are designed within the framework of a larger controlled clinical trial.

Adult↗

PubMed2005

Aerobic and functional capacities in a selected active population of European octogenarians.

Master athletes are often considered to represent the ideal rate of decline of aerobic function; however, most of the studies interested in active elderly people are often limited to people younger than 75. We aimed to determine the physiological adaptations and aerobic fitness in a selected European population of active octogenarians during maximal and submaximal exercise tests. Aerobic capacity was measured during maximal incremental tests on treadmill (TR) and cycle-ergometer (CE) and functional capacity during a 6-minute walk test (6-MWT) in 17 subjects aged 81.2 +/- 0.8 years. Pulmonary gas exchange and heart rate (HR) were continuously measured during the different exercise tests. Maximal oxygen consumption (V.O (2max)) on TR and CE was significantly higher than predicted values (TR: 28.7 +/- 1.2 vs. 17 +/- 0.5 ml . kg (-1) . min (-1); CE: 23 +/- 1.2 vs. 16 +/- 0.6 ml . kg (-1) . min (-1) for measured and predicted values respectively). V.O (2max) and HR (max), as well as V.O (2) and HR at the ventilatory threshold (V.O (2)T (V.E) and HR T (V.E)) were significantly higher on TR than on CE (HR (max): 144 +/- 4 vs. 138 +/- 4 bpm; V.O (2)T (V.E): 22.5 +/- 0.8 vs. 17.7 +/- 0.9 ml . kg (-1) . min (-1) for TR and CE respectively). V.O (2)T (V.E) and HR T (V.E) on TR were equivalent to V.O (2) and HR measured during the 6-MWT. HR T (V.E) on TR and mean HR during the 6-MWT were strongly correlated (R = 0.82, p < 0.01). Maintenance of regular physical activity provides high aerobic fitness, in octogenarians, as was shown by the higher values of our subjects in comparison to predicted values. Moreover, the close relation between the intensity developed at T (V.E) on TR and 6-MWT could support the idea that a walk test is a submaximal test performed at high intensity that could provide a basis for exercise prescription in an individualized manner in active elderly people.

Adaptation, Physiological↗

PubMed2006

Study on the usefulness of precise and simple dynamic balance tests for the evaluation of recovery from intravenous sedation with midazolam and propofol.

BACKGROUND AND OBJECTIVE: Dynamic balance involving movement of the centre of gravity is important for the evaluation of street fitness after sedation. The purpose of this study was to compare the recovery of dynamic balance after intravenous sedation with propofol or midazolam, and to investigate the usefulness of simple dynamic balance tests in evaluating the recovery. METHODS: Fourteen young male volunteers underwent intravenous sedation with propofol and midazolam for 1 h each at an interval of more than 1 week. Computerized dynamic posturography using a multi-axial tilting platform, the 10-m maximum-speed walking test and the timed 'up & go' test (subjects stand up from a chair, walk 5 m and back with maximum speed and sit down again) were performed before and after sedation. The increase in each variable of the tests described above represents a reduction of function. RESULTS: The score of the computerized dynamic posturography was significantly lower in propofol sedation than that in midazolam sedation until 40 min after the end of sedation (P = 0.006). The scores of maximum-speed walking test and timed 'up & go' test were significantly lower in propofol sedation than those in midazolam sedation till 60 min after the end of sedation, respectively (P = 0.035 and 0.042). The timed 'up & go' and maximum-speed walking tests were well and significantly correlated with computerized dynamic posturography in midazolam sedation (timed 'up & go' test vs. computerized dynamic posturography: r = 0.66, P < 0.01; and maximum-speed walking test vs. computerized dynamic posturography: r = 0.53, P < 0.01). CONCLUSION: The timed 'up & go' and maximum-speed walking tests are useful simple dynamic balance tests well correlated with precise computerized dynamic posturography for the evaluation of the recovery of dynamic balance from midazolam sedation in younger adults.

Adult↗

PubMed1998

"Value" of improved treadmill exercise capacity: lessons from a study of rate responsive pacing.

OBJECTIVES: To compare the value of a series of cardiovascular measurements in patients with symptomatic disease receiving an effective treatment (rate responsive pacing). PATIENTS: 12 pacemaker dependent patients with VVIR units. INTERVENTIONS: Single blind crossover between VVI and VVIR. OUTCOME MEASURES: Exercise capacity was assessed by treadmill tests (modified Bruce protocol and a fixed workload protocol) with respiratory gas analysis. Self paced corridor walk tests were also undertaken. Quality of life (QOL) was assessed by questionnaire. Daily activity was measured in the patients' homes using shoe and belt pedometers. RESULTS: Treadmill tests and QOL questionnaires correctly identified the clinical benefit associated with VVIR. The modified Bruce protocol was superior to the fixed workload protocol as it was better tailored to the fairly well preserved exercise capacity of the patients. Symptom scores, but not walking times, were improved with VVIR during corridor walk tests. VVIR did not improve daily activity measured using either the belt or shoe pedometers. CONCLUSIONS: VVIR pacing improved some but not all measures of exercise capacity. This finding illustrates the difficulty of selecting an instrument to measure symptomatic improvement in clinical research; and raises the question, what is the best way of measuring exercise capacity?

Activities of Daily Living↗

PubMed1975

Maximal oxygen uptake during treadmill walking and running at various speeds.

Three groups of male subjects, average fitness (AF, N = 12), high fitness (HF, N = 7) and highly fit competitive race walkers (CRW, N = 3) performed maximal treadmill tests walking at 3.5 and 4.5 mph and running at 4.5, 5.5, 7.0, and 8.5 mph. In addition, the HF group performed a running test at 10.0 mph and the CRW group performed a walking test at 5.5 mph. All maximal oxygen uptake (VO2 max) tests with the exception of the 3.5 mph walking test (modified Balke test) were discontinuous in nature. VO2 max obtained from walking tests was similar regardless of speed within each group. Walking VO2 max was significantly lower than running VO2 max which was found to be similar over a speed range of 4.5 to 8.5 mph in the AF group. Running at 4.5 mph (HF group) and 4.5 and 5.5 mph (CRW group) resulted in lower VO2 max levels than running at speeds greater than or equal to 7.0 mph. Associated physiological variables (heart rate, ventilation, and respiratory exchange ratio) did not demonstrate a discernable pattern with reference to mode of locomotion (walking versus running) or speed. It was concluded that VO2 max elicited during walking is independent of speed and less than VO2 max obtained during running. Running VO2 max was interrelated with speed of running and state of training.

Adult↗

PubMedDate not supplied

Enhancing theoretical fidelity: an e-mail-based walking program demonstration.

PURPOSE: To examine the extent to which theoretical fidelity, or precision in replicating theory-based recommendations, influenced the effectiveness of two walking programs based on social cognitive theory (SCT). DESIGN: Two-group randomized controlled trial. SETTING: College town in Virginia. SUBJECTS: Sixty-one sedentary adult women. INTERVENTION: Two 12-week e-mail-based walking programs were compared. The high fidelity program was designed to more precisely follow SCT recommendations for operationalizing mastery procedures than the low fidelity program, which was designed to simulate how mastery procedures were operationalized in most existing SCT-based physical activity programs. Treatment contact and walking prescription were controlled across groups. MEASURES: The 1-mile walk test of physical fitness and SCT measures were completed at baseline and posttest. Self-reported walking quantity was assessed at baseline, posttest, and 1-year follow-up. Walking logs were completed during the program. Process evaluation measures were completed at posttest. RESULTS: Fifty women completed the study. The high fidelity group improved more than twice as much as the low fidelity group on 1-mile walk test time (86 vs. 32 seconds, p < .05), goal setting (p < .05), and positive outcome expectations (p < .05) and reported greater program satisfaction (p < .01). CONCLUSION: Theoretical fidelity could advance the quality of physical activity interventions, which have often shown small effects.

Adult↗

PubMedDate not supplied

Analysis of the metabolic and ventilatory response to self-paced 12-minute treadmill walking in patients with severe chronic obstructive pulmonary disease.

BACKGROUND: The 12-minute walking test is frequently used to measure exercise capacity in patients with severe chronic obstructive pulmonary disease. However, the physiological response to this test has been the subject of limited investigation. METHODS: In this study, the metabolic and ventilatory consequences of a self-paced 12-minute treadmill walking test (WT) were measured in 17 patients with severe chronic obstructive pulmonary disease (FEV1: 40 +/- 9%) and evaluated using the physiological response to symptom-limited cycle ergometry (CE). During exercise testing, heart rate, transcutaneous oxygen saturation, and lactate concentration were measured, and oxygen consumption, carbon dioxide production, tidal volume, and breathing frequency were recorded breath by breath. RESULTS: After 4 minutes walking, the peak oxygen consumption (VO2) was already 99 +/- 11% of last-minute walking VO2. Walking speed was chosen within 2 minutes and remained stable throughout the test. The WT and CE showed similar (end-) test results for all measurements, except for a higher carbon dioxide production, venous lactate concentration, and respiratory quotient after CE. However, lactate concentration was also significantly increased after WT. Severe and prolonged desaturation was shown during walking in most patients. CONCLUSIONS: The physiological stress evoked during the WT is close to the stress developed at an incremental symptom-limited test and the relatively high metabolic and ventilatory stress is sustained from at least 4 to 12 minutes during the WT. This study has shown that anaerobic metabolism not only occurs during incremental cycle ergometry, but also during the WT.

Blood Gas Analysis↗

PubMed2002

[A case of chronic obstructive pulmonary disease (COPD) followed by pulmonary rehabilition].

We report a 75-year-old woman with chronic obstructive pulmonary disease (COPD) suffering from cough, sputum, high-grade fever and dyspnea on effort. Her chest radiograph revealed an infiltrative shadow in the right lower lung field and her laboratory data showed marked inflammatory changes. Her arterial blood gas analysis showed marked hypoxemia and hypercapnia. After her laboratory data and general condition improved, we performed pulmonary rehabilitation for the patient for about 6 weeks. The program consisted of pursed lip breathing, diaphragmatic breathing, muscle stretch gymnastics, and walking. The 6-minute walking test distance increased from 170 m to 280 m. The minimum SpO2 during the 6-minute walking test increased from 88% to 91%. (O2 3 L/m) After discharge, she continued to receive home care from a visiting nurse specialized in respiratory medicine and 24 hour-monitoring of O2-compliance at home. She has not experienced acute exacerbation or re-hospitalization for 1 year. We conclude that home care service is effective to maintain stable conditions such as state of breathing, SpO2, vital signs, and activities of daily living for elderly COPD outpatients.

Aged↗