Relative Effects of Bronchial Drainage and Exercise for

Relative Effects of Bronchial Drainage and Exercise for
In-Hospital Care of Patients with Cystic Fibrosis
Bronchial hygiene therapy is a standard part of the treatment of patients with cysticfibrosis(CF). Coughing alone promotes sputum expectoration and is probably
the primary effective component of standard bronchial hygiene therapy. The purpose of this study was to determine whether substituting regular exercise, which
also promotes coughing for two of three daily bronchial hygiene treatments
would affect the expected improvements in pulmonary function and exercise
response in hospitalized patients with CF. Seventeen patients with CF hospitalized
( length of stay = 130 ± 2.6 days) for an acute exacerbation of their pulmonary disease participated in the study. The patients were randomly assigned to
either a group that participated in two cycle ergometer exercise sessions and one
bronchial hygiene treatment session per day (EX Group[n = 9]) or a group that
participated in three bronchial hygiene treatment sessions per day (PD Group
[n =8]). Pulmonary functions and responses to a progressive, incremental cycle
ergometer exercise test were measured on admission and before discharge. Bronchial hygiene therapy consisted of postural drainage, in six positions, with chest
percussion and vibration. Therapeutic exercise was of moderate intensity and was
individually adjusted based on the patient's heart rate and arterial oxygen saturation response to the admission exercise test. Coughing was encouraged during
and after all treatments. Pulmonary function and exercise response were significantly improved over the period of hospitalization in both groups; the improvements were the same in the two groups. These results indicate that, in some hospitalized patients with CF, exercise therapy may be substituted for at least part of the
standard protocol of bronchial hygiene therapy. [Cerny FJ: Relative effects of bronchial drainage and exercise for in-hospital care of patients with cysticfibrosis.Phys
Ther 69:633-639, 1989]
Frank J Cerny
Key Words: Cysticfibrosis;Pediatrics, evaluation; Percussion; Pulmonary, bronchial drainage.
Chest physical therapy, including
bronchial hygiene techniques consisting of postural drainage, chest percussion, vibration, forced expiration, and
coughing, has been a standard part of
the treatment for children with cystic
fibrosis (CF).1-3 The objectives of
bronchial hygiene therapy are to
F Cerny, PhD, is Assistant Professor, Department of Pediatrics, Division of Pulmonary Disease, Children's Hospital, 219 Bryant St, Buffalo, NY 14222, and Department of Physical Therapy and Exercise
Science, State University of New York at Buffalo, 411 Kimball Tower, Buffalo, NY 14214. Address
correspondence to Department of Physical Therapy and Exercise Science, State University of New
York at Buffalo, 411 Kimball Tower, Buffalo, NY 14214 (USA).
This study was supported in part by NIH Grants 5R01AM24066 and RR-05493 and by The Buffalo
Foundation.
This article was submitted October 12, 1988; was with the author for revision for five weeks, and
was accepted March 3, 1989.
Physical Therapy/Volume 69, Number 8/August 1989
mobilize pulmonary secretions and
promote sputum expectoration.
Increased short-term sputum expectoration and improved lung function
have been reported after bronchial
hygiene therapy4-11 The patientparent time and effort required for
two to four daily bronchial hygiene
sessions often result in noncompliance and have led to a search for
alternate means of producing the
same effects. Studies that have examined the effects of the individual components of bronchial hygiene therapy
suggest that coughing alone may be
633/11
Table. Physical Characteristics of Patients
PFSb
Weight (kg)
Age (yr)
Groupa
Admission
Height (cm)
s
Admission
Discharge
s
s
s
Discharge
s
s
EX (n = 9)
15.4
4.9
149.5
14.6
35.9
10.5
36.9
11.1
12.2
1.3
9.8
1.1
PD (n = 8)
15.9
4.9
151.6
14.2
38.4
14.4
39.4
14.6
14.9
0.9
12.3
1.0
a
EX Group participated in two cycle ergometer exercise sessions and one bronchial hygiene treatment session per day; PD Group participated in three
bronchial drainage treatment sessions per day, except for one patient who received four treatments per day.
b
PFS = pulmonary function score.26
the primary effective element in stimulating sputum expectoration.12-18
Mellins observed that in many
patients exercise induced coughing,
suggesting that exercise may be an
alternative therapeutic modality for
facilitating sputum expectoration in
selected patients with lung disease.19
In support of this suggestion, regular
physical activity has been shown to
result in improvements in lung function in patients with CF.20-24 It is
unknown how incorporation of exercise into the physical therapy program
of patients with CF hospitalized for an
acute exacerbation of their lung disease will affect the changes in lung
function and exercise capacity occurring during the inpatient time period.
This report describes the effects of
replacing two of three daily bronchial
hygiene sessions with vigorous exercise on lung function and exercise
adaptation in hospitalized patients
with CF.
Method
Subjects
Patients in the study were admitted to
the hospital for treatment of an acute
exacerbation of their pulmonary disease. Admission was based on symptoms of increased shortness of breath,
coughing, and sputum production and
decreased lung function. Subjects who
were able to perform pulmonary
function tests and who gave written
informed consent were randomly
assigned to either a group that participated in two cycle ergometer exercise
sessions and one bronchial hygiene
treatment session per day (EX Group
[n = 9]) or a group that participated
in three bronchial hygiene treatment
sessions per day (PD Group [n = 8]).
No attempt was made to match
patients for disease severity. Patient
characteristics are shown in the Table.
Discharge was based on improvement
in one or more of the following: pulmonary function test results, chest
radiograph, shortness of breath, and
elimination of fever.
Procedure
Pulmonary function tests. Patients
performed pulmonary function and
exercise tests on the morning after
admission and on the morning of discharge. The first pulmonary function
test was performed two hours after
the first bronchial hygiene treatment.
All patients had previously performed
both pulmonary function and exercise
tests on multiple occasions. Forced
vital capacity (FVC), expiratory reserve
volume (ERV), inspiratory capacity
(IC), forced expiratory volume in one
second (FEV1), and forced expiratory
flow between 25% and 75% of FVC
(FEF25%_75%) were measured by
spirometry; functional residual capacity (FRC) and airway resistance (Raw)
*Hewlett-Packard Co, Waltham Div, 175 Wyman St, Waltham, MA 02154-9030.
†
Quinton Instrument Co, 2121 Terry Ave, Seattle, WA 98121.
12/634
were measured by body plethysmography.25,26 Residual volume
(RV = FRC - ERV), total lung capacity
(TLC = FRC + IC), and specific airways conductance (SGAW = 1/Raw x
FRC-1) were calculated. Percentage of
arterial oxygen saturation (Sao2) was
estimated with an ear oximeter.*
Pulmonary functions, with the exception of Sao2, were expressed as a percentage of predicted value.2728 In
addition, a pulmonary function score
(PFS), based on the deviation from
the predicted values for six pulmonary functions tests (FVC, FEV1,
FEF25%_75%, RV, SGAW, and Sao2), was
calculated.29 Test results within two
standard deviations of the expected
value received a score of 0. Scores of
1,2, and 3 were assigned for values
greater than two, three, and four standard deviations from the normal
mean, respectively. A total PFS of 0 to
<3 was considered normal, and
scores of 3 to 7, 8 to 12, and 12 to 18
were indicative of mild, moderate,
and severe lung dysfunction, respectively. This score has been shown to
correlate well with other clinical
scores29 and is used as an indicator of
general lung function.
Exercise test The exercise test was
performed on a cycle ergometer.†
The initial load of 0.3 W/kg was
increased by 0.3 W/kg every 2 minutes. Exercise was stopped when the
subjects could no longer continue
despite encouragement or when Sao2
had decreased by >15% or to less
than 75% of the baseline level. Arterial oxygen saturation, electrocardio-
Physical Therapy/Volume 69, Number 8/August 1989
graphic activity, and heart rate (HR)
were monitored continuously. Sub­
jects breathed from a low-dead space
(50 mL), one-way valve to allow mea­
surement of exhaled minute ventila­
tion (VE) in a Tissot gasometer for the
last 30 seconds of each work load.
Treatment All patients were treated
similarly with intravenous antibiotics,
inhaled bronchodilators, pancreatic
enzymes, and water-soluble vitamins
A and E and multivitamin prepara­
tions. Physical therapy was given
between 8 and 9:30 AM, 3 and 4:30
PM, and 7 and 9 PM. The PD Group
received postural drainage with chest
percussion and vibration in six posi­
tions for 20 to 40 minutes three times
daily, with the exception of one
patient who received two afternoon
treatments for a total of four treat­
ments per day. The postural drainage
was preceded by inhaled β2-receptor
agonist bronchodilators. The EX
Group exercised during the first two
sessions and received postural drain­
age during the third session. Cough­
ing was encouraged during and after
all therapy sessions. Coughs were
counted for 15 minutes following
each therapy session.
Exercise therapy was performed on a
cycle ergometer. The ear oximeter
was worn at all times. Exercise inten­
sity was adjusted to attain a target HR
established as a percentage of the
heart rate reserve (HRR = peak exer­
cise HR - resting HR)30 so that target
HR = HRR x percentage desired +
resting HR Resting HR was measured
in the laboratory after the patient had
been sitting quietly for 10 minutes.
Work loads in the first two days were
set to elicit a HR of 25% to 40% of
the HRR. This was a level that could
be tolerated for 5 to 10 minutes and
would not result in arterial oxygen
desaturation (Sao 2 = >2%), except in
two patients who received supple­
mental oxygen at a level to maintain
Sao 2 above 90% on Days 1 and 2.
After 3 to 4 days, all subjects were
able to exercise at a work level that
elicited a HR of at least 40% of their
peak HRR. From Day 4 to discharge,
exercise time was increased to a tar­
get duration of 15 to 20 minutes. By
the end of the hospitalization, each
patient was able to work at an inten­
sity of between 45% and 65% of the
HRR.
To determine the immediate effects of
exercise or bronchial hygiene therapy
on pulmonary functions, spirometry
was performed each day immediately
before the morning treatment, 15
minutes after the morning treatment,
and every hour for 5 hours after the
morning treatment. Daily sputum vol­
ume expectorated was determined by
measuring and summing the amounts
of sputum accumulated during the
following time intervals: from the
time of awakening (7-8 AM) to the
beginning of treatment, during and
for one-half hour following treatment,
from 9:30 to 11:30 AM, from 11:30 AM
to 2:30 PM, from 2:30 to 8:30 PM, and
from 8:30 PM to wake-up. Sputum
volume, wet weight, and dry weight
(after 4 days of drying in an oven)
were recorded and expressed in units
per hour.
Data Analysis
Significance of within-group changes
in each measurement of pulmonary
function and exercise adaptation,
from admission to discharge, was
determined using paired Student's t
tests. In addition, to determine
whether the extent of these changes
was different between the groups, a
Delta value for each pulmonary func­
tion test and measure of exercise
adaptation was calculated (Delta value
= discharge value - admission value)
and averaged for each group.
Between-group comparisons of these
Delta values were made using the
unpaired Student's t test. Betweengroup statistical comparisons for the
pulmonary function changes over the
five hours following physical therapy
were made on Days 1 and 7 using an
analysis of variance for repeated
measures.31 Significance was accepted
at the .05 level.
Results
The mean duration of the hospitaliza­
tion was 13 days (s = 3) for the EX
Group and 13 days (s = 2.6) for the
Physical Therapy/Volume 69, Number 8/August 1989
PD Group. Results of the pulmonary
function tests on admission and at
discharge are shown in Figure 1.
There were no PFS differences
between the EX and PD Groups at
admission or discharge. Compared
with the EX Group, the admission
FEV1 and FEF25%_75% were signifi­
cantly lower in the PD Group
(p < .05). The PFS, FVC, and FEF1
improved significantly in both groups,
whereas FEF25%_75% improved only in
the PD Group. Within-group changes
in the other pulmonary function tests
were not statistically significant. There
were no significant differences in the
Delta values, indicating that the extent
of the changes in all tests was the
same for both groups.
Results of the exercise tests
performed on admission and at dis­
charge are shown in Figure 2. On
admission, no significant betweengroup differences were observed in
any of the exercise variables. Peak
load (p < .02) and peak HR (p < .05)
improved from admission to
discharge in both groups. To adjust
peak VE and peak HR values for
potential changes in the load at which
they were attained, the ratios for peak
VE to peak load and peak HR to peak
load were calculated and compared.
The peak HR-to-peak load ratio
improved (p < .05) only in the EX
Group. The between-group compari­
son of admission to discharge Delta
values revealed no significant
differences.
All postural drainage treatments were
completed as required for the study,
and 96% of the scheduled exercise
therapy sessions were completed.
Both treatments induced a productive
cough and an equal number of
coughs. An acute (15 minutes posttreatment), but not statistically signifi­
cant, improvement in pulmonary
functions, which lasted over the 5hour follow-up period, was noted
after 85% of the treatment sessions
(Fig. 3). These trends were the same
on Day 1, the first full day of treat­
ment, as on Day 7 of the treatment
protocol, with no significant differ­
ences between groups (Fig. 3). There
were no differences in 24-hour spu635/13
turn volume and dry weight; the
greatest volume was collected after
the morning treatment, with no differences between the PD and EX
Groups.
Discussion
Some form of bronchial hygiene has
been part of the treatment program
for patients with CF since 1959 when
Doyle suggested that it may enhance
mobilization and expectoration of
sputum.32 Exercise may have similar
pulmonary hygiene effects.19 In this
study, hospitalized patients who substituted exercise for two of three
bronchial hygiene treatments showed
improvements in lung function and
exercise adaptation comparable to
patients who received the usual three
daily bronchial hygiene treatments.
Comparisons of the PD and EX
Groups are valid only if clinical status
was similar at admission. Although
between-group differences in admission FEV1 and FEF25%_75% were
observed, clinical status, as indicated
by the PFS,29 was the same in both
groups. Nickerson et al have shown
that individual pulmonary function
tests in patients with CF are significantly more variable than in healthy
subjects such that the assessment of
pulmonary status on the basis of a
single test could be artifactual.33 For
this reason, a combination of measures, such as the PFS, can be a more
reliable indicator of clinical status.34
Also supporting the suggestion that
the groups in this study were similar
in status is the fact that published
reports of improvement in pulmonary
function35"37 and exercise adaptation37
during a hospitalization and in pulmonary function immediately following treatment5,6,8,11 were qualitatively
the same as those in this study for
either group.
It could be argued that the equivalent
changes in lung function in the EX
Group were due to the single evening
bronchial hygiene treatment. Desmond et al reported that a single
bronchial hygiene treatment given
after a three-week no-treatment
period resulted in significant
14/636
Fig. 1. Means and standard deviations of changes (in percentage ofpredicted
value) in lung function during hospitalization in patients with cysticfibrosis.The PD
Group (n = 8) received three bronchial drainage treatments per day, except for one
patient who received four treatments per day; the EX Group (n = 9) participated in two
cycle ergometry exercise sessions and one bronchial hygiene treatment session per day.
Delta shows change for each group over period of hospitalization. (FVC —forced vital
capacity; FEV1 = forced expiratory volume in one second; FEF25%_75% = forced expiratory flow between 25% and 75% of FVC; FRC = functional residual capacity.)
increases in FVC and rate of airflow
at 60% of TLC (Vmax 60 TLC), but not
FEF25%_75%.11 They also reported
that FVC and Vmax 60 TLC, but not
FEF25%_75%, after this single treatment
were "similar" to values measured
prior to cessation of treatment. It is
unclear from these results as to what
the effects of a single, daily treatment
might be. The sputum data from the
present study do not support the idea
that the single evening bronchial
hygiene session could account for the
similarity in the groups. Sputum volumes collected in this study were
greatest after the first treatment in the
morning, regardless of whether the
treatment was postural drainage or
exercise, and daily volumes were the
same for both groups. These data
would suggest that a single bronchial
hygiene treatment, although having
some positive effect on lung function,
would not account for the lack of differences between the groups.
Early studies suggested that lung function was improved after postural
drainage.4-6,9,13 More recent studies
showed no short-term changes in pulmonary function in patients with
chronic obstructive pulmonary disease (COPD)8 or CF.11 It is difficult to
compare these studies because a variety of pulmonary function tests were
used for evaluation, the severity of
disease was dissimilar between studies, and the patients were not homogeneous within studies. Desmond et al's
study emphasizes the effect that previous therapy history might have on the
effectiveness of the therapy session
being evaluated.11
Studies examining the effectiveness of
bronchial hygiene therapy have confirmed an enhanced sputum expectoration or rate of mucus clearance as a
result of treatment.4,10-18 Others have
reported that coughing was the primary effective component of bron-
Physical Therapy/Volume 69, Number 8/August 1989
chial hygiene therapy in patients with
CF15,17 and COPD.18 Because coughing
was common to both types of therapy
in this investigation, the similarity of
the five-hour posttreatment response
in pulmonary function would support
the suggestion that coughing is the
important element in bronchial
hygiene therapy, regardless of how it
is elicited.
Regular exercise has been shown to
result in improvements in lung function in nonhospitalized patients with
CP. 20-24 These improvements were
attributed to ventilatory muscle training but may also be explained, in
part, by exercise-induced coughing or
acceleration of ciliary mucus
clearing.38 This suggestion is in agreement with Oldenberg et al,18 who
showed that exercise was more effective than postural drainage but less
effective than directed coughing in
the removal of sputum. The EX
Group did not receive bronchodilator
therapy before the exercise therapy
session. It is unknown how pretreatment with bronchodilators affects the
effectiveness of subsequent standard
bronchial hygiene treatments, and
therefore this issue cannot be
addressed.
Although the EX Group in this study
did show greater improvement in
several exercise variables than the PD
Group, these changes were small. The
short time of training (less than 13
days) and the low level of exercise in
the first seven days after admission
were below those levels required to
elicit a significant conditioning
effect.30
Conclusion
Substitution of exercise treatments for
two of three daily bronchial hygiene
treatment sessions over a nearly twoweek hospitalization in this study produced similar benefits in lung function and exercise capacity, suggesting
that postural drainage and exercise
were equally effective in promoting
Fig. 2 . Means and standard deviations of changes in measures of exercise adaptation during hospitalization inpatients with cysticfibrosis.The PD Group (n = 8)
received three bronchial drainage treatments per day, except for one patient who
received four treatments per day; the EX Group (n = 9) participated in two cycle ergometer exercise sessions and one bronchial hygiene treatment session per day. Delta
shows change for each group over period of hospitalization. (VE = exhaled minute ventilation; HR = heart rate.)
pulmonary hygiene. This study made
no attempt to isolate the effects of
coughing alone on lung function or
exercise response over the period of
hospitalization. In view of the available evidence, it is suggested that
under all conditions where sputum
expectoration should be promoted,
coughing must be encouraged.
Because exercise can be carried out
only when patients feel reasonably
well, standard bronchial hygiene or
other methods of inducing coughing
may be required to promote sputum
expectoration under certain conditions. This study found no negative
effects of exercise therapy performed
by inpatients. A limited, individualized
exercise program offers an opportunity for patients with CF to improve
their functional exercise capacity and
lung function with no apparent nega-
‡
Cystic Fibrosis Foundation, 6931 Arlington Rd, Bethesda, MD 20814.
Physical Therapy/Volume 69, Number 8/August 1989
tive consequences. In selected inpatients, exercise should be considered
an adjunct to, or substitute for, traditional physical therapy. Guidelines for
exercise testing and exercise prescription for patients with CF are available
from either the Cystic Fibrosis
Foundation* or the author.
Acknowledgments
I acknowledge the support of Dr GJA
Cropp and the technical assistance of
Pat Dolan.
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Fig. 3 . Changes (in percentage of amount recorded on admission) in forced vital
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