Portable Oxygen in Chronic Obstructive Lung Disease with Hypoxemia and Cor Pulmonale: A Controlled Double-Blind Crossover Study

doi:10.1378/chest.68.2.236

Chest

Volume 68, Issue 2, August 1975, Pages 236-241

https://doi.org/10.1378/chest.68.2.236 Get rights and content

SUMMARY

Nine patients with severe chronic obstructive lung disease with clinical and electrocardiographic evidence of cor pulmonale were selected. They had a mean resting PaO₂ of 53 mm Hg, which fell to 49 mm Hg on maximal exercise (P < 0.05). Each patient received five weeks of liquid oxygen therapy and five weeks of liquid air treatment in a portable gas apparatus (Linde walker) on a daily continuous basis. The results were evaluated with a paired t-test.

Portable liquid air breathing, compared to the control period before starting to use the portable gas apparatus, resulted in no changes in spirometric findings, gas diffusion, heart rate, exercise tolerance, distance walked per day (pedometer), ECG at rest and exercise, or arterial blood gas levels at rest and exercise. All patients stated that they “felt better” with than without the portable gas apparatus.

While receiving liquid oxygen, the group as a whole showed a significant fall in resting heart rate (P< 0.001). The PaO₂ during oxygen breathing increased to 84 mm Hg (P < 0.001). Within 4 to 24 hours after stopping the portable liquid oxygen, exercise studies were performed while breathing room air. There was an increase in PaO₂ at rest to 71 mm Hg (P < 0.001) and PaO₂ on maximal exertion to 65 mm Hg (P < 0.01).

All nine patients stated that they “felt better” with the portable gas apparatus than during the control period. Only three could clearly tell that they received something different during each five-week period. It was these patients who stated that the liquid air was “not as good.” They were the only patients to show an increase in distance walked per day by pedometer readings. The only distinguishing feature of this group was a greater fall in PaO₂ during exercise in the control period.

Portable liquid oxygen therapy is of more than placebo value in a highly selected group of patients with COPD, cor pulmonale, and hypoxemia at rest and exercise.

Section snippets

Selection

Nine men patients with COPD and an arterial oxygen tension (PaO₂) (sitting, breathing room air) of less than 60 mm Hg with clinical and electrocardiographic evidence for cor pulmonale were selected. These patients had all been treated in our respiratory ambulatory care unit for more than one year with physical rehabilitation, progressive exercise training, aerosol therapy, and bronchodilator therapy. They were all stable and showed no subjective change or change in exercise tolerance for three

RESULTS

The predictions for spirometric results and lung volumes are not shown, because the main purpose of the study was to see if there was a change from control to the two variables, rather than whether the tests were within the “normal range.”

Table 1 summarizes the findings in these patients. The group shows a severe airway obstructive disease (low FEV₁/FVC and high RV/TLC) with a reduced gas diffusion (Dsb) suggesting some decrease in alveolar capillary surface. There is moderate hypoxemia and

DISCUSSION

We have shown that continuous, portable liquid-oxygen therapy given during waking hours in a flow sufficient to correct hypoxemia is of greater than placebo value in a highly selected group of patients with COPD, cor pulmonale, and hypoxemia at rest and exercise. Whereas there was no change in any of the subjective or objective assessments while breathing portable liquid air, some definite changes occurred during and immediately after portable liquid-oxygen therapy. During the oxygen therapy,

ACKNOWLEDGMENTS

The authors would like to thank the Ontario Thoracic Society, Mr. Don Gratton of Union Carbide, and the technical staff of the Respiratory Unit, St. Joseph's Hospital, Toronto, particularly Bob Musselwhite and Wadieh Fakhry, for their superb technical assistance. The late Mr. R. G. Melrose was instrumental in setting up and controlling the technologic methods for the liquid air.

References (8)

TL Petty et al.
Clinical evaluation of prolonged ambulatory oxygen therapy in chronic airway obstruction
Am J Med
(1968)
JE Cotes et al.
Effect of oxygen on exercise ability in chronic respiratory insufficiency: Use of portable apparatus
Lancet
(1956)
AL Barach
Ambulatory oxygen therapy: Oxygen inhalation at home and out-of-doors
Dis Chest
(1959)
TA Neff et al.
Long term continuous oxygen therapy in chronic airway obstruction
Ann Intern Med
(1970)

There are more references available in the full text version of this article.

Cited by (47)

Oxygen Therapy and Noninvasive Ventilation in Chronic Obstructive Pulmonary Disease
2020, Clinics in Chest Medicine
Effect of ambulatory oxygen on exertional dyspnea in IPF patients without resting hypoxemia
2013, Respiratory Medicine
Citation Excerpt :
Furthermore, oxygen did not cause significant improvement in walk distance, leg fatigue, or heart rate in both tests. The effect of oxygen on dyspnea in COPD had been investigated in several studies [16–23]. Although oxygen improves exercise performance, its reported effects on dyspnea are conflicting.
The effects of ambulatory oxygen for idiopathic pulmonary fibrosis (IPF) patients without resting hypoxemia have not been elucidated. The purpose of this study was to assess the effect of ambulatory oxygen on dyspnea in IPF patients without resting hypoxemia but with desaturation on exertion.
This was a double-blind, placebo-controlled, randomized crossover trial of ambulatory oxygen versus ambulatory air. Patients with IPF who had a partial pressure of arterial oxygen (PaO₂) between 60 mm Hg and 80 mm Hg at rest, and desaturation of 88% or less in a room-air 6-min walk test were eligible. Patients underwent a standardized 6-min walk test and a 6-min free walk test under each ambulatory gas. Oxygen and air were provided at 4 L/min intranasally. Dyspnea was evaluated immediately, 1, and 2 min after the tests.
Twenty patients (16 men), with a mean age of 73.5 (SD 4.1) years, % predicted forced vital capacity (FVC) of 71.0 (13.3) %, % predicted diffusion capacity for carbon monoxide (DLco) of 57.0 (13.3) %, and PaO₂ of 72.5 (5.4) mm Hg were recruited. No significant differences in dyspnea were observed between ambulatory oxygen and air at each time point. However, some patients showed improvement in dyspnea with oxygen on an individual basis.
Since oxygen provides no additional benefit over air in terms of exertional dyspnea for IPF patients without resting hypoxemia, routine prescription of ambulatory oxygen is not recommended. However, assessment on an individual basis is necessary.
Trial registration. UMIN Clinical Trial Registry; No.:UMIN000005098; URL:http://www.umin.ac.jp/ctr/.
Patients with chronic obstructive pulmonary disease (COPD) who are not hypoxaemic at rest do not benefit from home oxygen
2011, Journal of Physiotherapy
Activity measurement
2006, Clinician's Handbook of Adult Behavioral Assessment
This chapter reveals that behavior is the final common pathway for the cumulative effects of heredity and environment including cognitive, affective, and behavioral processes. Activity level reflects all of these sources of variation and; therefore, varies due to a broad set of psychologically relevant factors. Actigraphy provides objective instrumented activity level measurements while participants behave in their natural environment. Actigraphy acts as the Swiss army knife of behavioral assessment, in that it has numerous uses of interest to both clinicians and investigators in psychology and medicine. No other behavioral assessment technology has so many diagnostic and outcome assessment applications. Modem actigraphs are simple to use and interface readily with personal computers. While the cost of actigraphs has decreased over the years, inexpensive pedometers are readily available for investigators and practitioners of more modest means. There is no longer any acceptable reason for depending entirely on ratings of activity level in research or clinical practice. The consequences of inaccurate assessment are much more immediate and certain in clinical practice than in research.
Refillable oxygen cylinders may be an alternative for ambulatory oxygen therapy in COPD
2002, Chest
Citation Excerpt :
As a source of ambulatory oxygen, O2-HFs may be an alternative to portable O2-Cs and liquid oxygen devices. Few clinical studies have compared the relative advantages of gaseous and liquid oxygen for portable use in patients with COPD.59 Comparing both devices in a prospective controlled study, Vergeret and Brambilla5 did not find any difference in total ambulatory oxygen use, and observed that compliance to long-term oxygen therapy was improved whatever the ambulatory system used.
To compare, in clinical conditions, the efficacy of refilled oxygen cylinders (O₂-HFs) in improving oxygenation and exercise capacity of patients with COPD during a 6-min walking test.
Prospective randomized study with a cross-over design.
A university teaching hospital.
Ten patients with COPD, in a stable state and previously treated with long-term domiciliary oxygen therapy. Baseline characteristics were as follows: age, 65 ± 7 years; Pao₂ on room air, 55.4 ± 6.3 mm Hg; Paco₂ on room air, 46.2 ± 7.4 mm Hg; FEV₁/vital capacity, 47 ± 7%; and FEV₁, 30 ± 7% of predicted value (mean ± SD).
All patients performed three successive 6-min walking tests, the first test in room air and the other tests in a randomized order with either a conventional oxygen cylinder (O₂-C) or an O₂-HF.
The fraction of inspired oxygen (Fio₂) delivered by O₂-HFs was significantly lower than the Fio₂ delivered by O₂-Cs (94.2 ± 2.6% vs 98.8 ± 4.9%, p = 0.02). Mean O₂-HF and O₂-C weights before the walking tests were similar (3,510 ± 251 g and 3,770 ± 142 g, respectively; p = 0.09). Mean transcutaneous oxygen saturation was similarly improved with both oxygen delivery systems. Mean distances with O₂-C (373.5 ± 81 m) and O₂-HF (375 ± 97 m) were not different but significantly improved, as compared with room air (334.5 ± 90 m; p = 0.03 and 0.02, respectively). Dyspnea sensations were similar for the three tests.
O₂-HFs are as efficient as O₂-Cs for performing short-term exercises. Because of a lower cost, pressurizing units may be worthwhile for improving ambulatory oxygen therapy and pulmonary rehabilitation programs.
A randomised trial of domiciliary, ambulatory oxygen in patients with COPD and dyspnoea but without resting hypoxaemia
2011, Thorax
Citation Excerpt :
Studies designed to examine its use have conflicting findings and are limited by small sample sizes.8–13 Lilker et al reported no change in dyspnoea, subjective assessment of activity or distance walked per day in nine patients with resting hypoxaemia randomised to air or oxygen in a 10 week crossover study,8 and Lacasse et al reported no impact on health-related quality of life (HRQoL) or exercise tolerance in a study comparing additional ambulatory air or oxygen in patients on long-term continuous oxygen therapy.9 Nonoyama et al reported no improvement in HRQoL after ambulatory oxygen compared with air in 27 patients with exertional desaturation over three pairs of 2 week treatments.10
Patients with chronic obstructive pulmonary disease (COPD) who are not severely hypoxaemic at rest may experience significant breathlessness on exertion, and ambulatory oxygen is often prescribed in this circumstance despite a lack of conclusive evidence for benefit. This study aimed to determine whether such patients benefit from domiciliary ambulatory oxygen and, if so, which factors may be associated with benefit.
This was a 12 week, parallel, double-blinded, randomised, placebo-controlled trial of cylinder air versus cylinder oxygen, provided at 6 l/min intranasally, for use during any activity provoking breathlessness. Patients underwent baseline measurements of arterial blood gases and lung function. Outcome measures assessed dyspnoea, health-related quality of life, mood disturbance, functional status and cylinder utilisation. Data were analysed on an intention-to-treat basis, p≤0.05.
143 subjects (44 female), mean±SD age 71.8±9.8 years, forced expiratory volume in 1 s (FEV₁) 1.16±0.51 lites, Pao₂ 9.5± 1.1 kPa (71.4±8.5 mm Hg) were randomised, including 50 patients with exertional desaturation to ≤88%. No significant differences in any outcome were found between groups receiving air or oxygen. Statistically significant but clinically small improvements in dyspnoea and depression were observed in the whole study group over the 12 weeks of the study.
In breathless patients with COPD who do not have severe resting hypoxaemia, domiciliary ambulatory oxygen confers no benefits in terms of dyspnoea, quality of life or function. Exertional desaturation is not predictive of outcome. Intranasal gas (either air or oxygen) may provide a placebo benefit.
ACTRN12605000457640.

View all citing articles on Scopus

Supported by the Ontario Thoracic Society and St. Joseph's Hospital (Toronto), Research Foundation.

Presented at the 39th Annual Meeting, American College of Chest Physicians, Toronto, Oct. 21-25, 1973.

View full text

Chest

Respiratory TherapyPortable Oxygen in Chronic Obstructive Lung Disease with Hypoxemia and Cor Pulmonale: A Controlled Double-Blind Crossover Study

SUMMARY

Section snippets

Selection

RESULTS

DISCUSSION

ACKNOWLEDGMENTS

Am J Med

Lancet

Dis Chest

Long term continuous oxygen therapy in chronic airway obstruction

Ann Intern Med

Respiratory Therapy
Portable Oxygen in Chronic Obstructive Lung Disease with Hypoxemia and Cor Pulmonale: A Controlled Double-Blind Crossover Study