A Comparative Study of 3 Portable Oxygen Concentrators During
a 6-Minute Walk Test in Patients With Chronic Lung Disease
Carole J LeBlanc RRT, Lyne G Lavallée PT, Judy A King PhD PT,
Rebecca E Taylor-Sussex, Andrew Woolnough MSc, and Douglas A McKim MD

BACKGROUND: The purpose of this study was to compare the ability of 3 portable oxygen
concentrators (POCs) to maintain SpO2 > 90% during exercise in patients with chronic lung disease.
METHODS: Twenty-one subjects with chronic lung disease (18 with COPD, 3 with pulmonary
fibrosis) and documented room air exertional SpO2 < 85% performed four 6-min walk tests: acontrol walk using the subject’s current oxygen system and prescribed exertional flow rate, and 1
walk with each of the 3 POCs (Eclipse 3, EverGo, and iGo) at their maximum pulse-dose setting.
RESULTS: SpO2 was significantly higher pre-walk and post-walk with the Eclipse 3, compared tothe other POCs (all P < .01). The subjects also walked farther and maintained a mean SpO2 > 90%with the Eclipse 3 (both P < .01), which delivers the largest oxygen bolus. The subjects indicatedthat they preferred the EverGo’s physical characteristics, but that the Eclipse 3 responded best to
their breathing. The iGo was rated less favorably than Eclipse 3 or EverGo. CONCLUSIONS: The
Eclipse 3 was best at meeting the subjects’ clinical needs. POC users should be appropriately tested
during all activities of daily living, to ensure adequate oxygenation. The healthcare provider should
provide information and help to direct the subject toward the most clinically appropriate oxygen
system, while being mindful of the patient’s preferences and lifestyle. (Clinicaltrials.gov
NCT01653730). Key words: COPD; oxygen; instrumentation; pulmonary fibrosis; exercise test; ambulatory care; walking. [Respir Care 2013;58(10):1598 –1605. © 2013 Daedalus Enterprises]

Introduction
Long-term oxygen therapy (LTOT) is indicated for patients with chronic lung disease, and is universally accepted for its effect on mortality in patients with COPD
and persistent hypoxemia.1,2 Supplemental oxygen improves exercise performance, enhances exercise training,
and reduces dyspnea.3,4

Ms LeBlanc, Ms Lavallée, and Dr McKim are affiliated with the Ottawa
Hospital Rehabilitation Centre; Ms Lavallée, Dr King and Dr McKim
are affiliated with the University of Ottawa; and Ms Taylor-Sussex andMr Woolnough are affiliated with the Ottawa Hospital Research Institute,
Ottawa, Ontario, Canada.
The portable oxygen concentrators were donated by the manufacturers
for this study. The manufacturers had no role in the design or conduct of
the study. This research was partly supported by a grant from the Institutefor Rehabilitation Research and Development, the Ottawa Hospital
Rehabilitation Centre, Ottawa, Ontario, which had no role in the study
design, data collection or analysis, or preparation of the manuscript. The
authors have disclosed no other conflicts of interest.

1598

Patients with chronic lung disease using LTOT benefit
from an active lifestyle, and portable oxygen systems areof particular interest to this patient population. The challenge for clinicians is in selecting the most appropriate
portable oxygen system and meeting the patients’ current
and future clinical and physical needs.5-13 The 6th LTOT
consensus conference recommended that physicians, patients, and home-medical-equipment providers effectively
collaborate to ensure LTOT users have access to the mostMs LeBlanc presented a version of this study at the Canadian Respiratory
Care Conference, held April 28–30, 2011, in Niagara Falls, Ontario,
Canada. Ms Lavallée presented a version of this study at the Canadian
Physiotherapy Association Congress, held May 23–27, 2012, in Saskatoon, Saskatchewan, Canada.
Correspondence: Carole J LeBlanc RRT CRE, Ottawa Hospital Rehabilitation Centre, 1201-505 Smyth Road, Ottawa, Ontario K1H 8M2,
Canada. E-mail: cleblanc@ottawahospital.on.ca.
DOI: 10.4187/respcare.02275

RESPIRATORY CARE • OCTOBER 2013 VOL 58 NO 10

A COMPARATIVE STUDY OF 3 PORTABLE OXYGEN CONCENTRATORS
appropriate technologies for their clinical and lifestyleneeds.14
Portable oxygen concentrators (POCs), whose only dailyrequirement for maintenance is access to electricity to recharge the batteries, present an attractive option when compared to compressed gas and liquid oxygen systems. However, studies have shown that POCs do not always maintainadequate oxygenation during exercise,5,7,13 and bench studies have shown decreases in FIO2 in POCs as breathing
frequency increases.9,12 These studies give reason for concern, since evidence suggests that maintaining SpO2 ⱖ 90%
offers a survival advantage.15
A small number of studies have examined how variations in the technical specifications between POCs affectclinical outcomes in exercising patients. Subramaniam
et al10 compared 3 POCs during a 10 min treadmill test andfound no statistical differences in SpO2 or walking distance.
However, a second group did find a difference between 3
POCs during a treadmill test, concluding that higher oxygen delivery capacity was associated with improved exercise outcomes and oxygenation.5,13

QUICK LOOK
Current knowledge
Supplemental oxygen during exercise reduces dyspnea
and improves exercise performance in patients withhypoxemia due to chronic lung disease. Portable oxygen concentrators promote mobility, but their ability toreverse exercise-related hypoxemia is suspect.
What this paper contributes to our knowledge
The portable oxygen concentrator with the largest oxygen pulse-dose volume was best at meeting subjects’clinical needs. Home oxygen patients should be tested
during all activities of daily living, including exercise,to ensure adequate oxygenation. Patients should be directed toward the most clinically appropriate portable
oxygen system, but also consider patient preferences
and lifestyle.

6-Min Walk Test

SEE THE RELATED EDITORIAL ON PAGE 1711

In an attempt to reconcile the disparity in these results
and to determine if POCs are capable of meeting patients’
oxygen needs during exercise (SpO2 ⱖ 90%), we chose toevaluate 3 POCs using a standardized 6-min walk test
(6MWT) in patients with chronic lung disease with severe
exertional oxygen desaturation. We also measured patients’personal POC preferences.
Methods
This study was approved by the Ottawa Hospital Research Ethics Board (2009845-01H). All subjects gave written informed consent before their screening assessment.
Study Design and Setting
A within-subject, repeated-measures design was used
to compare 3 POCs during an exercise test. The subjects
attended 2 sessions at the Respiratory Services, CANVent
Program of the Ottawa Hospital Rehabilitation Centre.
During the initial screening session, clinical characteristics were measured to determine the patient’s eligibility
for the study. Eligible patients then returned for a second
session, where they completed 4 6MWTs: 1 with theirusual portable oxygen source, and 1 with each of the 3
POCs.

RESPIRATORY CARE • OCTOBER 2013 VOL 58 NO 10

The 6MWT is a reproducible, self paced, walk test,
reflective of activities of daily living.16 A physiotherapist
and a respiratory therapist conducted all of the walks using
the American Thoracic Society 6MWT standards andscript.17
Subjects
Oxygen dependent patients with an existing diagnosis
of COPD or pulmonary fibrosis who had completed thepulmonary rehabilitation program at the Ottawa Hospital
Rehabilitation Centre between January 30, 2008, andMarch 31, 2011, were invited to participate in the study.
While the pathophysiology of pulmonary fibrosis is different than COPD, and the ability of POCs to maintainoxygenation during exercise may differ, this patient population also benefits from and partakes in an active lifestyle. They therefore need access to and/or guidance on theappropriateness of portable oxygen systems. For these reasons patients with pulmonary fibrosis were included in the
study.
During the screening session, patients completed a
6MWT on room air to determine their eligibility for theremainder of the study. Patients who maintained SpO2 ⬎85% during the walk were excluded (Fig. 1).
Equipment
We selected the 3 POCs with the highest oxygen production capabilities (mL/min) that were available in our

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A COMPARATIVE STUDY OF 3 PORTABLE OXYGEN CONCENTRATORS
unit’s maximum pulse-dose setting. The Eclipse 3 was the
only device with adjustable rise time and triggering sensitivity features. For all the subjects the sensitivity was set
at “1” (most sensitive) and rise time set at “Fast.”
The order in which POCs were used was randomly assigned for each subject, using a sequence generator tominimize order effects. Subjects completed the walk using
their usual mode of ambulation (eg, walker with basket).
Each 6MWT was separated by a minimum 20-min rest
period to allow their SpO2 to return to baseline, during
which the subject used his or her own oxygen system atthe prescribed resting setting. Subjects were placed on theassigned POC 10 min prior to the next walk. The therapist
terminated a walk if the subject’s SpO2 reached ⱕ 85% for
any length of time. Subjects also had the option to terminate a walk at any time, based on their own judgment ofperceived exhaustion.
Outcome Measures
Fig. 1. Flow chart.

region: EverGo (Respironics, Murrysville, Pennsylvania),iGo (DeVilbiss Healthcare, Summerset, Pennsylvania), andEclipse 3 (Caire Medical, Ball Ground, Georgia). Technical specifications can be found in Table 1. We tested these
POCs’ ability to meet the subjects’ oxygenation needs.
Since POC pulse-dose settings are most frequently used bypatients on LTOT, to conserve battery power, each unit
was set at its maximum pulse-dose setting. For the control
walk the subjects used their personal portable oxygen device, on the setting prescribed for paced exercise (Table 2).
Screening Session
On the day of the screening assessment the subject’s
medical history was obtained and FEV1 and FVC were
measured (CPFS/D, Medical Graphics, St Paul, Minnesota). The subject then performed a qualifying room air
6MWT while SpO2 was monitored.

SpO2 was measured continuously during the walk, using
a forehead probe (OxiMax Max-Fast, Covidien, Mansfield, Massachusetts) with headband, and an oximeter (OxiMax N-600 or N600x, Covidien, Mansfield, Massachusetts). Heart rate was monitored during the walk to ensureprobe connectivity and to ensure subject safety, but is notreported. After each walk, oximetry data were downloaded
to a computer (Profox Oximetry Software, Profox Associates, Escondido, California). SpO2 and dyspnea (as measured by the 10-point Borg dyspnea scale)18 were manually recorded before the start (pre-walk) and at the end(post-walk). Total distance walked and time spent with
SpO2 ⱖ 90% was recorded. Post-walk the subjects completed a self-administered questionnaire designed by the
researchers to allow them to rate the POCs (Fig. 2).
Statistical Analysis

Qualifying subjects returned to the clinic within 3 weeks
for a second session. These subjects each performed 4
separate 6MWTs during this second session. Two walks
were completed in the morning, followed by a minimum
2-hour lunch break, and then 2 walks in the afternoon. The
first 6MWT was a control walk in which the subject used
his or her usual oxygen system set at the prescribed exertional oxygen flow (maximum 4 L/min). The subject thenperformed a 6MWT with each of the 3 POCs, set at the

Pre-walk and post-walk SpO2 saturations and Borg scores
were analyzed using repeated-measures analysis of variance with time point (pre-walk vs post-walk) and POC
type as within-subject repeated factors. Pairwise post hoccomparisons applying Bonferonni corrections for multiple
comparisons were done to further examine significant effects. A second repeated-measures analysis of variance
was completed for outcomes measured only once (walkdistance, time with SpO2 ⱖ 90%) with POC type as thewithin-subject repeated factor. Questionnaire data were
examined with descriptive analyses. All analyses were completed with statistics software (SPSS 18 or 19, SPSS, Chicago, Illinois).

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POC Testing Session

A COMPARATIVE STUDY OF 3 PORTABLE OXYGEN CONCENTRATORS
Table 1.

Technical Specifications of the Tested Portable Oxygen Concentrators

Maximum O2 delivery, mL/min
O2 pulse-dose bolus volume, mL
Purity of O2, %Pulse-dose setting
Trigger sensitivity, cm H2O
O2 delivery method
FDA clearance status
Noise level, dBa
Weight, kg
Dimensions, cm
Battery duration, hBattery recharge time, hiGo 306D S-AEclipse 3

EverGo3,000
14–84
91 ⫾ 3
1–6⫺0.05 to ⫺0.12
Continuous up to 3 L/min
Pulse-dose maximum setting 6
Approved up to 4,000 mL/min
40 at pulse-dose setting 3
8.6 with one battery
49.0 H ⫻ 31.2 W ⫻ 18.0 D
3.0 at pulse-dose setting 6(bolus 84 mL) andbreathing frequency
20 breaths/min
3/battery

3,000
16–19290 ⫾ 3
1–6⫺0.15 to ⫺0.45
Continuous up to 3 L/min
Pulse-dose maximum setting 6
Approved up to 4,000 mL/min⬍ 49
8.4 with one battery
49.0 H ⫻ 31.2 W ⫻ 18.0 D
3.5 at pulse-dose setting 6(bolus 96 mL) andbreathing frequency
12 breaths/min
2–3/battery

1,050
12–70
89 ⫾ 3
1–6⫺0.2
Pulse-dose maximum setting 6
Approved up to 2,450 mL/min⬍ 50
4.5 with two batteries
21.6 H ⫻ 15.25 W ⫻ 30.5 D
4.0 with pulse-dose of 6(bolus 70 mL) andbreathing frequency 20/min
2–3/batterydBa ⫽ decibels measured on the a-weighted scale

Table 2.

Oxygen Systems, Pulse-Dose Settings, and Oxygen Flows by Number of Subjects

Device Type

Compressed gas oxygen cylinder(E or D size)
Liquid oxygen
EverGoEclipse 3
InogenUsed
Pulse-Dose
Oxygenno. subjects

Pulse-Dose
Setting(or Range)

Used
Continuous
Flow Oxygen
no. subjects

Continuous
Flow Setting(or Range)
L/min

4

1–5

1

3

1
3
1
1

1.5
2–2.5
4
4

9
0
1
0

1–4
0
2
0

Results

6-Min Walk Test Results

Of the 35 patients who completed the rehabilitation program and were oxygen dependent, 24 agreed to participate, 2 of whom failed to meet the SpO2 criteria during thescreening room air 6MWT, and another was excluded due
to poor SpO2 tracking, leaving 21 subjects in the analyses(12 females). The subjects had a mean ⫾ SD age of
66.57 ⫾ 8.36 y (range 53– 82 y). Eighteen subjects werediagnosed with COPD, and 3 with pulmonary fibrosis.
The mean percent-of-predicted FEV1 was 32.22 ⫾ 11.67%
in the subjects with COPD, and 61.0 ⫾ 7.94% in thesubjects with pulmonary fibrosis. The mean FEV1/FVC
was 42.22 ⫾ 16.35% in the subjects with COPD, and85.67 ⫾ 4.04% in the subjects with pulmonary fibrosis.
Fifteen subjects used a wheeled walker to carry thePOCs, and 6 used the manufacturer provided POC wheeling device.

The 6MWT results and reasons for walk termination arepresented in Table 3. Eighty-six percent of the subjects
walked for the full 6 min using the Eclipse 3, as compared
to 52% using either the iGo or the EverGo. One walk wasterminated by the subject, during an EverGo trial; all otherterminations were initiated by the therapist, due to oxygen
desaturation.
There was a significant interaction between POC
type and the pre-walk versus post-walk SpO2 measurements(P ⫽ .006). Post hoc tests showed that SpO2 was higher
pre-walk (P ⬍ .001) and was highest with the Eclipse 3(P ⬍ .001 for all comparisons of Eclipse 3 to iGo and
EverGo). The Eclipse 3 had higher mean SpO2 both prewalk and post-walk, and the SpO2 decrease between prewalk and post-walk was the smallest with Eclipse 3(Fig. 3).
The during-walk SpO2 of the 3 subjects with pulmonary
fibrosis were within the distribution of all the subjects.

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Subject Demographics and Baseline Characteristics

A COMPARATIVE STUDY OF 3 PORTABLE OXYGEN CONCENTRATORS
time with SpO2 ⱖ 90% (control P ⬍ .001, EverGo P ⬍ .001,
iGo P ⫽ .001). The Eclipse 3 was the only POC to maintain a mean SpO2 ⱖ 90% for the duration of the walk.
Questionnaire Responses
The subjects consistently gave neutral (3) or disagree(1 or 2) questionnaire responses for the iGo. The subjects
rated the EverGo most favorably for the questions about
the device’s physical characteristics (86% of subjects rated
EverGo 4 or 5 for each statement), whereas the Eclipse 3
received the most favorable response regarding the device’s ability to respond to breathing (95% of subjects
gave a rating of 4 or 5). The EverGo and the Eclipse 3
received comparable responses to the remaining statements, with ratings of 4 or 5 in 81% and 76% of thesubjects for “easy to use while walking,” 50% and 48% for“felt comfortable with device,” and 52% and 43% for“would consider for future use” (Table 4).
Discussion

With the Eclipse 3, 2 of the 3 subjects with pulmonary
fibrosis maintained SpO2 ⱖ 90% for the duration of
the walk, and the 3rd subject maintained SpO2 ⬎ 85%. The
subjects with pulmonary fibrosis did not maintain
SpO2 ⬎ 85%, nor did 7 of the 18 subjects with COPD, with
the iGo or EverGo.
While the mean Borg score was significantly higher
post-walk than pre-walk (P ⬍ .001), there was no significant Borg score difference between the POCs (P ⫽ .20).
There was a significant difference between the POCs
for time spent with SpO2 ⱖ 90% (P ⬍ .001) and total
distance walked (P ⫽ .001). Post hoc analyses indicatedthat the subjects walked farther with the Eclipse 3 (control
P ⫽ .01, EverGo P ⫽ .009, iGo P ⫽ .008) and spent more

This study compared the ability of 3 POCs to maintainadequate oxygenation during a 6MWT in a well definedgroup of subjects with chronic lung disease. Despite using
the maximum pulse-dose setting for each device, theEclipse 3 was the only POC to maintain a mean SpO2 ⱖ
90% for the duration of the 6MWT, and showed significantly better performance on all outcome measures. The
difference in walk distance between the Eclipse 3 and theother 2 POCs was also clinically important.19 Furthermore,
the subjects rated the Eclipse 3 as the best to respond totheir own spontaneous breathing patterns during exercise.
Although the Eclipse 3 and the iGo have the same highoxygen production capability (3,000 mL/min), they did
not demonstrate equivalent performance. This is in contrast with the results found by McCoy et al,5,13 who concluded that having a POC with a greater oxygen production capacity improved SpO2 and exercise outcomes.
Instead, we found that post-walk SpO2 and walk distancewere more similar between the EverGo and the iGo thanthe Eclipse 3, despite the fact that the EverGo has a published oxygen production capability about one third thatof the other 2 POCs (1,050 mL/min). Based on these POCs’technical specifications, we speculate that the most probable characteristic contributing to the performance differences was the O2 pulse-dose bolus volume. While thebolus volume ranges of the iGo and EverGo are similar,
the Eclipse 3 is much larger (see Table 1). In line withresults reported by Chatburn and Williams,9 we suggestthat the larger O2 pulse bolus volume of the Eclipse 3 wasan important contributing factor enabling it to better meetthe subjects’ oxygen needs during exercise.

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RESPIRATORY CARE • OCTOBER 2013 VOL 58 NO 10

Fig. 2. Self-administered questionnaire about portable oxygen
concentrators.

A COMPARATIVE STUDY OF 3 PORTABLE OXYGEN CONCENTRATORS
Table 3.

6-Min Walk Test Results, and Reasons for Walk Termination

SpO2, %Pre
Post
Borg dyspnea score
Pre
Post
Time with SpO2 ⱖ 90%, min:sDistance, mean ⫾ SD m
Completed walk, %Subject decided to stop walk, %Asked to stop by therapist, %Control

EverGoEclipse 3

iGo

96.14 ⫾ 2.48
86.67 ⫾ 3.60

95.90 ⫾ 2.98
87.24 ⫾ 3.96

98.62 ⫾ 1.69*
92.19 ⫾ 5.20*

96.19 ⫾ 2.80
86.86 ⫾ 4.49

0.21 ⫾ 0.49
3.14 ⫾ 1.73
2:39 ⫾ 1:43
262.62 ⫾ 107.54
62
038

0.26 ⫾ 0.49
3.55 ⫾ 2.02
2:38 ⫾ 2:05
237.43 ⫾ 116.04
52
543

0.24 ⫾ 0.49
3.14 ⫾ 1.82
5:16 ⫾ 1:33*
315.52 ⫾ 93.45*
86
014

0.24 ⫾ 0.52
3.50 ⫾ 1.58
3:11 ⫾ 2:16
227.62 ⫾ 118.81
52
0
48⫾ values are mean ⫾ SD.
* Significant (P ⬍ .01) difference, compared to all the other portable oxygen concentrator trials.

In spite of the Eclipse 3’s superior performance formeeting clinical needs, subjects rated the EverGo and the
Eclipse 3 similarly when asked if they would use the device in the future. Clearly, the physical characteristics ofthe EverGo, as the lightest and smallest POC, were important to subjects. Clinicians should educate patients thatthe goal of supplementary oxygen is to satisfy blood oxyhemoglobin needs and that this should be the first consideration in selecting a POC. The current study tested 3
specific POC models, and, although the technology willchange, the recommendations and principles for determining the best POC for patients will remain. It is important
to consider not only production capability but also bolus
volume when helping patients choose the right POC.
During the control 6MWT most of the subjects desaturated to unacceptable levels. It is clear that subjects’
usual paced walking prescription and oxygen device
were unable to meet the oxygen requirements of strenuous
exercise. During rehabilitation, patients are instructed in
how to pace themselves during exercise, in order to minimize oxygen desaturation. Clinicians should ensure thatpatients are aware of the limitations of their devices andhave appropriate oxygen prescriptions for all activity levels. This study should raise awareness of POC variability
and that clinicians should focus on clinical outcomes under conditions as close as possible to real life. Clinicians
and patients should test any potential new device to ensure it meets their clinical needs during activities of dailyliving. Patients’ preferences (ie, for lighter, smaller, ormore convenient devices) should only be considered once
potential devices have been demonstrated to meet theiroxygen needs.
Fig. 3. SpO2 before and after four 6-min walk tests: control (subject’s usual portable oxygen system), with the iGo POC, with the
Eclipse 3 POC, and with the EverGo POC. * Significant SpO2 difference between Eclipse 3 and EverGo or iGo.

RESPIRATORY CARE • OCTOBER 2013 VOL 58 NO 10

Limitations
We did not test whether these POCs met their advertised
product specifications. Our interpretation therefore assumes

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A COMPARATIVE STUDY OF 3 PORTABLE OXYGEN CONCENTRATORS
Table 4.

Summary of Questionnaire Data
Percent of Subjects Who Selected This Response
Question

Have you ever used this apparatus in the past?
The equipment was easy to use while walking.

The equipment responded well to my breathing while walking.

The weight of the equipment was acceptable.

The size of the equipment was acceptable.

I would consider this device for daily use.

I feel comfortable with this device.

Response*iGo

Eclipse 3

EverGo

Yes
No
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5

0
100
10
10
38
14
29
5
19
29
24
24
33
29
24
5
10
33
33
14
10
10
43
38
5
5
10
24
29
29
10
10

19
81
0
0
24
33
43
0
5
0
38
57
25
20
30
15
10
5
19
43
10
24
24
19
14
19
24
0
10
43
29
19

14
86
10
0
10
24
57
24
24
19
5
29
5
0
10
29
57
5
0
10
38
48
19
10
19
19
33
10
20
20
20
30

Response number range: 1 ⫽ strongly disagree, 5 ⫽ strongly agree.

that no product defects or anomalies were present.
Further, although subjects with COPD and pulmonary fibrosis were included in the sample, there was an insufficient number of subjects with pulmonary fibrosis to dogroup analyses. Despite this, visual inspection of the datasuggests that the subjects with pulmonary fibrosis had patterns of performance on the different POCs similar to thesubjects with COPD. Future studies should aim to recruit
more subjects with pulmonary fibrosis, to determine if
their needs are different from subjects with COPD. Additionally, due to methodological constraints we did not measure breathing frequency, which might have affected these
POCs’ ability to meet subjects’ oxygen needs. Future studies
should measure breathing frequency during ambulation.
Inhaled medication use was also not specifically mon-itored. Although none of the subjects was observed taking
rescue inhaled medication, the subjects were not always
visible to the therapists conducting the testing, in particular during lunch breaks and between walks. Nevertheless,since the measurements were made within subjects, andthe order in which the POCs were used was randomly
assigned, it is unlikely that there would be an effect of
bronchodilator use that would have affected any one POC
more than another.
Finally, it should be recalled that this study involves
selected subjects who desaturated to below 85% during aroom air walk test, so our results do not preclude thepossibility that any of the POC devices tested could provide adequate oxygenation for subjects who have lesser
degrees of desaturation.

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A COMPARATIVE STUDY OF 3 PORTABLE OXYGEN CONCENTRATORS
Conclusions
These findings suggest that subjects with chronic lungdisease exhibit considerable improvement in their ability
to maintain SpO2 when exercising with the Eclipse 3. We
have shown that bolus size can be an important factor in
determining the effectiveness of a POC, and healthcare
professionals should be mindful of patients’ current andfuture oxygen needs at all activity levels when guidingthem in the selection of their own POC.
ACKNOWLEDGMENTS
We thank the subjects who participated in this research; Paula Baxter RRT at the Ottawa Hospital Rehabilitation Centre, who assisted incoordinating the testing sessions; and Ronald Racette who assisted withthe grant and ethics proposals.
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