Transcript Pulmonary Rehabilitation

Pulmonary Rehabilitation
March 9, 2006
Howard M. Mintz, M.D.
ATS Guidelines: PR 1999
What and Why
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Reduce symptoms
Increase physical and social activities
Improve quality of life
Decrease disability
Questionable increase in survival
Economic savings
Exclusion Criteria for PR
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Advanced arthritis
Cognitive deficits
Recent MI
Severe pulmonary hypertension
Poor motivation
*Current smokers
ATS Guidelines: PR 1999
• Secondary co morbidities are the reason
that PR works
• *PR really changes items other than
respiratory function
• See table
Changes in PFT’s with PR
• Innumerable studies have demonstrated that typically
measured parameters of pulmonary function such as the
FEV1, FVC, FEV1/FVC do not change with pulmonary
rehabilitation
• Are we looking at the wrong parameters?
• “Arm Exercise and Hyperinflation in Patients with
COPD.” Gigliotti, et.al. Chest 2005: 128:1225-1232.
Instead of looking at static lung volumes, they examined
the response to exercise and changes in exercise
induced inspiratory capacity as a measure of
hyperinflation. Inspiratory capacity diminishes with upper
extremity and lower extremity exercise and PR
decreases the dynamic hyperinflation.
Assessment for PR
• Individualized programs are best suited for success
• PE, history, medication review, spirometry to assess
degree of obstructive disease
• Educational assessment to better understand that
patients knowledge of their disease process
• *Determination of baseline exercise capacity, what’s
necessary, check for desaturation, consider cardiac
comorbidity, respiratory muscle strength, nutritional
status, cognitive functional assessment
Site for PR
Exercise Training in PR
• High intensity training is more effective in producing training effect
• Most PR programs stress endurance training instead of high
intensity training, typical pattern would be 20-30 minutes two to five
times weekly
• Research would suggest intensity of training should be at 60% of
maximal oxygen consumption.
• Seldom do patients undergo a formal exercise stress test prior to PR
and instead a target HR is guide
• HR is poorly substitute since HR in severe lung disease is highly
variable because of the medications, comorbid conditions, and
underlying lung impairment.
• Symptom guided exercise program is a reasonable alternative
Does Pulmonary Rehabilitation
Work?
Exercise Training
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Lower extremity exercise
Upper extremity exercise
Continuous or intermittent
Weight training
Inspiratory and expiratory muscle training
Task specific training
What Does the Data Reveal?
#1
• “Controlled Trial of Supervised Exercise Training
in Chronic Bronchitis”, Sinclair, et. al. Br Med J
1980, Feb 23;280 (6213):519-521). 33 subjects
with severe chronic bronchitis. Exercise
consisted of 12 minute walk and stair climbing
with once weekly supervision. Exercise group
attained a 24% increase in maximum exercise
capacity after 8-12 months. No improvement in
the control group. No changes in respiratory
muscle strength nor PFT’s.
What Does the Data Reveal?
#2
• “Randomized Controlled Trial of Respiratory
rehabilitation,” Goldstein, Lancet 1994 Nov 19;
344(8934):1394-1397). Prospective randomized
controlled trial of 89 patients (45 females and 44 males),
mean age 66, stable COPD. Rehabilitation vs.
conventional community care. 24 week program, 8 as
inpatient and 16 as outpatient with supervision. Outcome
measurements were exercise tolerance and quality of
life. 6 minute walk, submaximal cycle time, perception of
dyspnea all improved in the rehabilitation group in
comparison to conventional treatment.
What Does the Data Reveal?
#3
• “Quality of Life in Patients with COPD Improves After
Rehabilitation at Home.” Wijkstra,et al. Eur Respiratory J
1994 Feb;7(2):269-273. Severe COPD patients with
FEV1 of 1.3 +/- 0.4 liters and FEV1/FVC 37% +/-7.9%.
43 patients with 28 receiving home rehabilitation for 12
weeks, and 15 usual care. Significant improvement in
dyspnea, emotional well being, and mastery of tasks. No
improvement in PFT’s and the improvement in quality of
life was independent of the improvement in exercise
tolerance.
What Does the Data Reveal?
#4a
• “Rehabilitation for Patients with COPD: Meta Analysis of
Randomized Controlled Trials.” Salman, J. Gen Internal
Medicine 2003 Mar;18(3):213-221. Studies were
included in patients were symptomatic, FEV1<70%,
FEV1/FVC <70%, at least 4 weeks duration. Outcome
measurements included exercise capacity or SOB.
• 69 trials, only 20 included in final analysis
• 20 of the trails showed improved walking distance
compared to control group
• 12 trials showed improvement in less shortness of breath
• Respiratory muscle training only did not show a
significant improvement in dyspnea nor walking distance
What Does the Data Reveal?
#4b
• Trials that included at least lower extremity exercises
showed improvement in dyspnea and walking distance.
• Those patients with the most severe disease only
improved with programs lasting six months or longer
• Those patients with mild to moderate disease improved
with both short rehabilitation and long rehabilitation
programs
• Mild upper extremity weight training has been shown to
give added benefit in addition to walking with decreased
minute ventilation and increased ergometer distance
(16%)
Skeletal Muscles and Enzyme
Changes with PR #1
• “Exercise Training Fails to Increase Skeletal Muscle
Enzymes in Patients with COPD.” Belman Am. Rev Resp
Disease 1981 Mar;123(3):256-261. Six week training
period. 7 patients did upper extremity exercises, and 7
patients did lower extremity exercise. Pre-exercise
biopsies were taken and post-exercise training biopsies
of the trained limbs. Enzymes citrate synthase, 3-beta
hydroxyacyl coenzyme A dehyrogenase, and pyruvate
kinase. The patients demonstrated a training effect, but
no changes in enzymes were detected. Hypothesized
that patients with COPD were unable to train at enough
intensity. Distinctly different than normal subjects.
Skeletal Muscles and Enzyme
Changes with PR #2a
• “Skeletal Muscle Adaptation to Endurance Training in
Patients with COPD.” Maltais. Am. J. Resp Crit Care
Med 1996 Aug;154(2pt1):442-7. Patients with severe
COPD, FEV1 36% +/- 11%. 30 minutes of calibrated
exercise on a ergocyle for 12 weeks. Pretraining aerobic
capacity was severely reduced but increased by 14%
with training. Training effect manifest by decrease in VE
for the same level of workload and a decrease in lactic
acid production. Muscle biopsies were obtained pre and
post training of the vastus lateralis.
• Two oxidative enzymes, citrate synthase (CS) and 3hydroxyacyl-CoA dehydrogenase (HADH) were
measured, pre and post.
Skeletal Muscles and Enzyme
Changes with PR #2b
• Three glycolytic enzymes were measured: lactate
dehyrogenase, hexokinase, and phosphofructokinase
were measured.
• The two oxidative enzyme levels increased, while the
glycolytic enzymes remained the same in pre and post
training muscle biopsies
• The increase in the oxidative enzyme levels was
associated with a decrease in lactate production at the
same level of exercise.
• Training even in patients with moderate to severe COPD
can improve skeletal muscle oxidative capacity.
Skeletal Muscles and Enzyme
Changes with PR #3
• “Reductions in Exercise Lactic Acidosis and Ventilation as a Result
of Exercise Training in Patients with Obstructive Lung Disease.”
Casaburi. Am Rev Respir Dis 1991 Jan;143(1):9-18.
• Question was does the intensity of the exercise determine the
benefit.
• Moderate COPD. Training at two levels of intensity, about 70 W x 45
minutes and 30 W at a proportionally longer period of time.
• After training, those in high intensity were able to increase level of
work without increase in lactate and less VE with 73% increase in
endurance.
• Low intensity group was able to increase endurance by only 9%.
• The absence of development of lactic acidosis is not required by a
training effect.
Predictors of Improvement with PR
• “Predictors of Improvement in the 12 Minute Walking Distance
Following a Six Week Outpatient Pulmonary Rehabilitation
Program.” Zuwallack. Chest 1991 Apr;99 (4):805-808
• 50 ambulatory outpatients exposed to six weeks of PR
• 12 MD increased by 27.7% +/- 32.5%
• 12 MD distance increased by 462 feet +/-427 feet.
• No significant relationship between age, sex, ABG’s, oxygen
requirements, and PFT’s
• Patient’s with highest ventilator reserve (1- [VEmax/MVV] x 100) had
the most improvement in 12 MD
• The smaller the initial 12 MD and the greater the initial FEV1, the
better the rehab potential
• Poor initial 12 MD is not a predictor of poor PR potential
• Studies showed the most improvement in those patients receiving
the most intense exercise prescriptions
Upper Extremity Exercise #1
• “Upper Extremity Exercise Training in COPD.” Ries.
Chest 1988 Apr; 93(4):688-692
• Patients with COPD have more difficulty with upper
extremity exercise
• Mechanism for increase in dyspnea includes fixation of
the rib cage and abdominal wall with upper extremity
exercises resulting in a physiologic stiffening of the rib
cage.
• Most PR programs emphasize lower extremity training
• 45 patients divided into three groups: gravity-resistance
training (GR), modified proprioceptive neuromuscular
facilitation upper extremity training (PNF), and no
specific upper extremity training
Upper Extremity Exercise #2
• 28 patients completed the study. GR and PNF showed
improved performance of task specific exercises.
• Breathlessness and perceived fatigue diminished.
• No change in ventilatory muscle strength or simulated
activities of ADL.
• In order to help patients with COPD improve ADL skills of
upper extremities, the prescription must be specific.
Upper Extremity Exercise
• “Supported Arm Exercises vs Unsupported Arm Exercises in the
Rehabilitation of Patients with Severe Chronic Airflow Obstruction.”
Martinez. Chest 1993 May; 103(5):1397-402.
• Patients were divided into those with unsupported arm training
(USA) and supported arm training (SAT). USA patients basically
lifted light weights. SAT used a hand ergometer.
• All patients were enrolled in comprehensive PR including lower
extremity, inspiratory muscle training, teaching, and psychological
support.
• Groups were equally matched from disease severity and exercise
capacity.
• 12 MW, respiratory muscle function, bicycle ergometer power output
similar in the two groups at the end of the training period.
• USA patients had a decrease in VO2 and the metabolic costs. USA
is much more akin to ADL skills and thus should be incorporated into
PR
Upper Extremity Exercise &
Dynamic Hyperinflation #1
• “Arm Exercise and Hyperinflation in Patients with
COPD.” Gigliotti, et.al. Chest 2005: 128:1225-1232.
• 12 patients with moderate to severe COPD, mean FEV1
1.59 liters +/- 0.58 liters and FEV1/FVC 46% +/- 12%.
• No changes in the static PFT’s nor ABG’s per and post
PR
• Hypothesis was that PR increased exercise tolerance
and decreased dyspnea because of changes in dynamic
hyperinflation.
• Dynamic hyperinflation is the phenomenon in which
exercise causes increases in the FRC & decreases in
the IC
Upper Extremity Exercise &
Dynamic Hyperinflation #2
• Consequences of dynamic hyperinflation include
a reduction in airway closure minimizing
expiratory flow resistance (maladaptive
response), increase in muscle fatigue by
changing the length tension relationship
• 12 patients underwent incremental (5W/min),
symptom limited arm exercises with hand
ergometer.
• Significant education and training period that
included lower extremity exercises and typical
components of PR
Upper Extremity Exercise &
Dynamic Hyperinflation #3
• 6 week outpatient PR.
• Expired gas analysis was performed along with
other routine measurements
• During the last 30 seconds of exercise, the
patients performed two inspiratory capacity
manuevers for measurement of end-expiratory
lung volume. TLC does not change during
exercise in patients with COPD, thus IC reliably
estimates changes in EELV.
• Patients rated dyspnea with Borg scale 0-10
Upper Extremity Exercise &
Dynamic Hyperinflation #4
• Hand ergometer training consisted of work load of 80%
of maximal level to symptom limited with 80% set by pre
PR testing.
• Study showed significant increases in minute ventilation,
oxygen consumption, CO2 production, HR, exercise
dyspnea with upper extremity exercise.
• Increase in work rate demonstrated with p<0.001.
• IC decreased by 0.93 +/- liters with upper extremity
exercise in the control period
• Following PR, IC decreased by 0.59 liters +/- 0.27 liters
(p<0.0001)
Upper Extremity Exercise &
Dynamic Hyperinflation #5
• The RR interval increased with PR, and thus there was
more expiratory time, associated with less dynamic
hyperinflation (p<0.03)
• Dyspnea as assessed by the Borg scale diminished
(p<0.02) follow PR
• HR decreased following PR
• Oxygen consumption and CO2 production did not
change with PR
• Minute ventilation decreased with PR, (p<0.01)
• Arm or leg cycling in COPD results in dynamic
hyperinflation and is a predictor of exercise tolerance
Inspiratory Muscle Training in PR
• The inspiratory muscles can be strengthened with
inspiratory muscle training
• The data on effectiveness of inspiratory muscle training
is mixed
• Inspiratory muscle training seems to decrease dyspnea
• Inspiratory muscle training has not been uniformly shown
to increase exercise endurance.
Inspiratory Muscle Training in
COPD #1
• “The Effects of 1 Year of Specific Inspiratory Muscle Training in
Patients with COPD.” Beckerman, et.al. Chest 2005; 128:31773182.
• Inspiratory muscle dysfunction likely result of geometric changes in
diaphragm, chest wall, systemic factors, and possible changes in
muscles.
• Hypothesis was that one year of SIMT would improve dyspnea,
exercise tolerance, quality of life, reduce hospital costs and
admissions
• 42 patients with mean FEV1 of 1.21 liters +/- 0.4 liters and FEV1 %
predicted of 42% +/- 2.6%
• Testing with spirometry, 6 MW, Borg scale for dyspnea
• Health-Related Quality of Life with St. George’s Resp Questionaire
Inspiratory Muscle Training in
COPD #2
• Training of 2 sessions of 15 minutes six times weekly for 12 months
with POWERbreathe, inspiratory muscle trainer. 1st month direct
supervision at center, then home training for 11 months with weekly
calls or visits. Attendance was 63% +/-7% in training group and 59%
+/- in the control.
• After 3 months of training, PImax increased in the trained group with
smaller incremental improvement over the next 9 months. P<0.005
• After 3 months of training, 6MW in trained group with smaller
incremental improvement over the next 9 months. P<0.005
• POD declined slowly and did not reach a statistically significant level
of p<0.05 until 9 months of training
• SGRQ improved after 6 months in trained group and was
maintained over 12 months
• No significant differences in hospitalizations between the trained and
control group, but average days for each hospitalization was lower in
trained group, p<0.05.
Inspiratory muscle strength as assessed by the PImax before and after the
training period in the study group and in the control group
Beckerman, M. et al. Chest 2005;128:3177-3182
The mean {+/-} SEM perception of dyspnea (Borg score) during breathing against
load in all COPD patients before and after the training period
Beckerman, M. et al. Chest 2005;128:3177-3182
The mean {+/-} SEM distance walked in 6 min before and after the training period
in the study group and in the control group
Beckerman, M. et al. Chest 2005;128:3177-3182
Changes in health-related quality-of-life scores determined by the SGRQ before
and after the training period in the study group and in the control group
Beckerman, M. et al. Chest 2005;128:3177-3182
Hospital admissions, days spent in the hospital, and the use of primary-care
consultations during the training period in the study group and in the control
group
Beckerman, M. et al. Chest 2005;128:3177-3182
Expiratory Muscle Training in
COPD #1
• “Specific Expiratory Muscle Training in COPD.” Chest 2003;
124:468-473. Weiner, et.al.
• Expiratory muscles impaired in COPD
• Contraction of expiratory muscles increases intrathoracic pressures,
decreases lung volumes, and increase expiratory flow rates.
• Expiratory muscle training has been shown to decrease dyspnea in
children with neuromuscular disease and improve cough in adults
with MS.
• Study was designed to answer three questions: 1. Does SEMT
increase exercise tolerance; 2. Does SEMT training decrease
dyspnea, 3. Can one demonstrate a training SEMT increase
Expiratory Muscle Training in
COPD #2
• Randomized study of 26 patient with mean FEV1 of 1.32
liters +/- 0.4 liters with FEV1 of 37% of predicted +/2.4%.
• Exercise sessions of 30 minutes six times weekly
• Expiratory muscle endurance as measured by PemPeak
increased by 33%, p<0.001
• 6MW increased in the treated group b 19%, p<0.05
• No significant change in perception of dyspnea with
expiratory muscle training
• Literature does not substantiate a significant individual
benefit for this modality
Breathing Retraining, Education,
Other Modalities
• Shallow, rapid breathing may be deleterious to ventilation and gas
exchange. Pursed lipped breathing and other techniques may help.
• Yoga training has been shown to improve exercise tolerance in
comparison to breathing exercise, only 11 patients in both groups
• Patients instructed in diaphragmatic breathing training actual had
more dyspnea and increase in work of breathing (7 patients)
• Educations goal is to improve compliance, no studies convincingly
show improvements
• Psychological support cannot be shown to have any specific benefit
although depression is about 2.5 times more prevalent in patients
with COPD. Group therapy has not been demonstrated to have
benefit.
• Energy conservation techniques, planning, prioritization, and
assistive devices.
• Discussion of end of life issues.
• Nutrition
Nutrition and COPD
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Weight loss to level of <90% of
IBW occurs in 25% to 43% with
about 14% of patients having
weight loss in excess of 50% of
premorbid weight
Weight loss with loss of lean body
mass is associated with skeletal
muscle dysfunction that
contributes to dyspnea, decreased
mobility, and increase risk of falls.
Significant weight loss typically
begins about 3.5 years prior to
death
Unintentional weight loss and
mortality
30%
30%
weight loss mortality in
3 years
50%
50%
weight loss mortality in
5 years
Nutrition and COPD
• At an FEV1 of <35% of predicted, those patient with >IBW have a
50% higher exercise capacity than patients with <90% of ideal body
weight
• Body weight is correlated with exercise capacity with p<0.0001.
• Reversal of weight loss has been associated with improved
outcomes such as increased survival and improvements in 12 MWD,
hand grip, PEmax, and PImax.
• Difficulty to restore body weight
• Patients with low body weight have more gas trapping, lower DLCO,
and lower exercise capacity when matched for patients with similar
pulmonary functions but normal weight
Nutrition, COPD, and Anabolic
Steroids #1
• “Reversal of COPD-Associated Weight Loss Using the
Anabolic Agent Oxandrolone.” Yeh, et. al. Chest 2002
122:421-428.
• Oxandrolone oral anabolic steroid shown to be useful in
patients with chronic infections, burns, severe trauma,
extensive surgery, offset catabolism associated with
corticosteroids.
• Oxandrolone has a high anabolic activity and low
androgenic activity (Testosteron 1:1 ratio & oxandrolone
3:1 to 13:1.
• Safety demonstrated in over 30 years of us.
Nutrition, COPD, and Anabolic
Steroids #1
• Community study, 25 sites in USA, 10 mgm of oxandrolone for 4
months, males and females
• History of involuntary weight loss and IBW <90% with COPD and
FEV1<50% of predicted
• No specific exercise program or nutritional support offered
• 128 patient entered study but only 55 analyzed for 4 months
• IBW 79% +/- 9.2% of predicted
• Mean FEV1 34% +/- 15.83%
• At 2 months, 72/82 patients had gained mean of 6.0 lbs +/-4.36 lbs
• At month 4, 46/55 patients had gained 6.0 lbs +/- 5.83 lbs (p<0.0)
• Males and females had equal response and body cell mass
increased substantially while body fat did not
Nutrition, COPD, and Anabolic
Steroids #2
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No changes in spirometry
No changes in 6 MW
No changes in VAS for dyspnea
Subgroup did demonstrate an increase in 6 MW and
performance status, but it is unclear why these patients
were separated
Meta-Analysis for Nutritional
Support in COPD
• “Nutritional Support for Individuals with COPD.” Ferreira,
et al. Chest 2000; 117:672
• RCT reviewed and 272 abstracts with 9 felt adequate for
data extraction with 272 subjects (144 study and 133
control)
• At least 2 weeks of nutritional support (any caloric
supplementation)
• Did this impact FEV1 or 6 MW? NO!!
Anabolic Steroids and PR in COPD
#1
• “A Role for Anabolic Steroids in the Rehabilitation of
Patients With COPD?” Creutzberg, et al. Chest
2003;124:1733-1742
• Low levels of testosterone are seen in COPD patients
especially those receiving glucocorticosteroids
• Glucocorticosteroids contribute to respiratory and
peripheral muscle weakness seen in COPD independent
of muscle wasting
• Anabolic steroids might work through effects on
erythropoietin
• Does the anabolic steroids nandrolone 50 mgm IM q 2
weeks benefit patients undergoing 8 weeks of PR?
Anabolic Steroids and PR in COPD
#2
• Measured were body composition, muscle function,
exercise capacity, erythropoietic values, and laboratory
values
• Subgroup analysis looked at patients receiving oral
glucocorticoids
• PR rehabilitation improved the following variables in both
the patients receiving Nandrolone and those receiving
placebo, but the addition of the Nandrolone did not
confirm an additive benefit: Maximum inspiratory muscle
strength, maximum isometric hand grip, maximum
isometric leg strength, work load, maximum oxygen
consumption, SGRQ scores
Greater improvements in maximal (Max) inspiratory muscle strength (top) and
peak workload (bottom) after 8 weeks of treatment with ND vs placebo combined
with a standardized pulmonary rehabilitation program in patients receiving oral
glucocorticosteroids
Creutzberg, E. C. et al. Chest 2003;124:1733-1742
Assessing Effectiveness of PR
• Dyspnea indices
• Quality of life indices
• Measurement of exercise capacity, 6 MW,
12 MW, 10 m Intermittent Shuttle test,
incremental cycle ergometer
Exercise Testing in PR #1
• Pulmonary rehabilitation is not free, and you need to
document effectiveness. What is simple, reproducible,
and cost effective?
• Incremental exercise on bicycle ergometer or treadmill to
85% of maximal predicted heart rate (HR, RR, BP, ECG,
SaO2, (+/- exhaled gas analysis). Reproducible and
sensitive to changes associated with PR.
• Submaximal testing on bicycle ergometer or treadmill
used to assess endurance. More effort dependent,
captures response to PR.
Exercise Testing in PR #2
• 6 minute walking test and 12 minute walking test can be conducted
anywhere
• 6 MW and 12 MW are less reproducible. Walk as far as you can, at
your own pace for 6 or 12 minutes. Simple. Well tolerated,
consistent with ADL.
• 6 MW and 12 MW correlate with peak exercise tolerance of graded
(incremental exercise) tests. Learning effect.
• 10 meter Shuttle Walking Test. Walks up and down 10 meter
(Shuttle) with increasing speed by external beeping. Incremental test
thus measure exercise capacity and not so much endurance. Self
pacing is eliminated. Correlation is r = 0.88 in comparison to
maximal oxygen consumption during incremental testing.
• Very responsive to changes associated with PR.
Comparison of 6 MW, 10m IST, &
CET #1
• “Physiologic Responses to Incremental and Self-Paced Exercise in
COPD. Turner, et al ”Chest 2004; 126:766-773
• Comparison of HR, SaO2, and dyspnea with these three exercise
modalities
• Hypothesis was that there would be no differences in peak HR or
dyspnea scores in patients with moderate to severe COPD
• 20 stable subjects, 18 with FEV1 <40% of predicted, FEV1/FVC
33.7% +/- 10.7%. 19 were ex smokers and 1 current smoker. 12/20
previously had PR.
• Each subject underwent the 3 exercise forms within a two week
period in a randomly selected order. 10m IST and 6 MW both have a
learning curve
Comparison of 6 MW, 10m IST, &
CET #2
• CET pedaling at 60-75 revolutions per minute against 20
W workload with increase of 8 W every minute until
subject unable to keep rpm pace or voluntarily stopped.
• 6MW on 45 m course, indoors, level surface.
• 10 m IST with initial walking speed of 0.5m/sec and
increase in speed every minute by 0.17m/sec. Verbal
cues to increase walking speed and triple beeps. Failure
to maintain speed, terminated period or voluntary
• HR before and every minute of exercise, SaO2 before
and end of exercise, Borg scale before and every minute
of exercise.
• 6MW subjects can stop for fatigue or dyspnea
Comparison of 6 MW, 10m IST, &
CET #3
• 6 MW HR increased more rapidly and in alinear fashion
• 10m IST and CET heart rate increased slower and linear
fashion
• Peak heart rate and dyspnea scores did not differ with
the three forms of exercise
• SaO2 was lower with 6 MW and 10m IST than with the
CET (p<0.001)
• 9/20 subjects has SaO2’s <85% with 6 MW or 10m IST,
but was >85% at termination in all patients with CET
• Strong correlation between distances walked with 6 MW
and 10m ICS with r=0.91.
Pooled data from 20 subjects of the changes in HR during the 6MWT, ISWT, and
incremental CET
Turner, S. E. et al. Chest 2004;126:766-773
Pooled data from 20 subjects of the changes in dyspnea during a 6MWT, ISWT,
and incremental CET
Turner, S. E. et al. Chest 2004;126:766-773
Comparison of 6 MW, 10m IST, & CET #4
• Distance walked with 6 MW and 10m IST correlated with peak
workload during CET with r=0.83; p<0.001 and r=0.79; p<0.001
respectively
• Significant correlation between peak oxygen consumption on CET
and distance walked on 6 MW and 10m IST with r=0.73, p<0.001,
and r=0.73, p<0.001 respectively.
• Walking is more suitable for detection of exercise induced
desaturation
• Peak HR and dyspnea scores similar between three tests
suggesting validity of using simplier exercise tests to assess results
of PR in patients with moderate to severe COPD
Measuring Dyspnea
• Most debilitating symptom in COPD
• Measured with Borg scale or visual analog scale
(VAS)
• Borg scale uses descriptions such as no
breathlessness to maximal breathlessness.
• VAS is 100 mm in length, one end no
breathlessness and other maximal
breathlessness
Dyspnea Assessment
• Functional status can be measured with
many different questionnaires to assess
changes
• Quality of life also assessed with
questionnaires.
• Usefulness of data is limited in assessing
benefits to individual patients, group
responses do improve with PR
Durability of Effectiveness of PR
• Normal trained individuals, cessation of training for about two weeks
causes loss of training effect
• Similar lack of durability for patients with COPD
• Study looking at long term effectiveness following 12 weeks of
pulmonary rehabilitation followed by visits monthly, weekly, and no
rehabilitation. Patients undergoing pulmonary rehabilitation had a
significant improvement in maximal cycle rate and 6 MW. 18 months
following completion of the PR, neither group receiving visits had a
sustained benefit, no difference between weekly and monthly follow
up. Adherence to home PR not assessed.
• Another study showed that at 12 months, despite monthly follow up
and encouragement for home therapy, substantial decline in benefit.
Adherence to home PR not assessed.
Enhancing Exercise Performance
in PR #1
• “Enhancement of Exercise Performance in COPD
Patients by Hyperoxia.” Snider. Chest 2002; 122:18301836.
• Medicare payment policy for oxygen therapy for
breathlessness was not considered reimbursable.
• What do the studies suggest about use of supplemental
oxygen in patients with severe COPD?
• Hyperoxia sufficient oxygen to result in an increase in
PaO2.
• 16 studies, only one randomized, controlled, studies date
back to 1956.
Enhancing Exercise Performance
in PR #2
• 1956 Cotes and Gilson studied 29 patients, all coal
miners with 18 with pneumoconiosis. 22/29 walking
distance on treadmill at least doubled with oxygen. The
improvement was minimal on 25%, and incremental
improvement on 30-50%, but no more up to 100%. VE
dropped by 26.5%
• 1970 Raimondi studied 8 pateints with severe COPD,
mean FEV1 0f 0.74 liters. 35% supplemental oxygen vs
RA, 35% improvement in exercise endurance.
• 1978 Bradley 26 men and women with mean FEV1 of
0.52 liters, exercised on treadmill with compressed air or
5 lpm of oxygen, 47% improvement in exercise
endurance.
Enhancing Exercise Performance
in PR #3
• 1982 Wookcock 10 patients with mean FEV1 of 0.71 liters.
Graduated exercise on treadmill with VAS. 25% increase in distance
walked on treadmill and 24% decline in dyspnea by VAS.
• 1992 Dean measured endurance testing on bicycle ergometer and
RVSP by Doppler echocardiography. RA or 40% FIO2. Duration of
exercise increased from 10.3 minutes to 14.2 minutes (p<0.005) and
RVSP at maximal exercise decreased from 71 to 64 mm Hg
(p<0.03). 12 patients studied with mean FEV of 0.89 liters.
• 1995 McDonald in only controlled, blinded study showed minimum
benefit, however, the patients had demand valve oxygen instead of
continuous and limited to 4 lpm
• Should supplemental oxygen be utilized? Should patients be tested
with and without oxygen therapy?
PR and survival