Chest
Opinions/HypothesesEnhancement of Exercise Performance in COPD Patients by Hyperoxia: A Call for Research
Section snippets
Summary of Literature
In 1956, Cotes and Gilson4 reported that portable oxygen therapy, given in a blinded fashion, usefully increased exercise performance in most of 29 patients with severe respiratory insufficiency. Twenty-eight of the 29 patients in the study had been coal miners, 18 had pneumoconiosis, and all had chronic bronchitis and emphysema. In 22 of 29 patients, walking distance on a treadmill was at least doubled when they were breathing oxygen. Studies of maximally effective oxygen concentration
Clinical Trial of Hyperoxic Exercise
There has been only one double-blind, randomized, crossover trial assessing the effects of supplemental oxygen therapy during exercise on quality of life. McDonald and colleagues20 measured the effects of therapy with supplemental air and oxygen, at 4 L/min, on exercise performance during a step test and a 6-min walk test that were performed before and after two 6-week periods at home while breathing compressed air or oxygen during exercise. Spo2 and Borg dyspnea score were measured during
The Physiology of Hyperoxic Exercise in Chronic Airflow Obstruction
Airflow obstruction is the hallmark of COPD. Resting hyperinflation of the lungs, as indicated by increases in functional residual capacity and total lung capacity, is frequent in patients with severe COPD. Tidal breathing occurs over a less advantageous portion of the length-tension curve of the diaphragm. Work done by accessory muscles of respiration is increased.13 During exercise, the ventilatory muscles are unable to do the work necessary to adequately increase tidal volume. Tachypnea and
Suggested Action Plan
It is estimated that in the United States there are currently about 16 million persons with COPD. There were 107,000 deaths due to COPD in 1998, and, extrapolating from the 1998 data, in the current year there will be about 115,000 deaths due to COPD.26 Assuming that on the average, persons have severe COPD for 10 years before they die, it follows that of the 16 million persons with severe COPD currently alive in the United States, at least 1.2 million (7.5%) have severe disease. A conservative
The Research Questions
- 1.
What is the prevalence of COPD patients, who are not receiving LTOT and who have severe airflow limitation (ie, FEV1, < 1.0 L or 35% of predicted values) and mild hypoxemia (ie, resting Spo2, ≥ 90%)?
- 2.
What proportion of severely obstructed, mildly hypoxemic COPD patients will improve their exercise endurance in a brief test?
- 3.
Is improved performance during a brief hyperoxic exercise test translated into a meaningful increase in the activities of daily living?
It is apparent that, apart from a full
The Next Step
It is beyond the scope of this essay to spell out the precise procedures for answering these questions. However, I have some suggestions for consideration by experts in the rehabilitation of persons with COPD.
Hyperoxia Endurance Test
Since pulmonary function tests do not predict who will benefit from oxygen treatment, an exercise endurance hyperoxia test should be developed that will indicate which patients might benefit from supplemental oxygen therapy during exercise. Almost 10 years ago, Leach et al17 pointed out that training runs were needed for both an endurance walk and a 6-min walk, but that fewer runs were needed for the endurance walk. More importantly, these authors showed that the endurance walk was more
Hyperoxic Exercise Performance
If preliminary studies warrant, a randomized, clinical, interventional trial should be organized to determine whether exercise hyperoxia has a therapeutic role in the segment of the population of COPD patients with high-grade airflow obstruction but limited hypoxemia. The end points of the study should be enhanced exercise performance, decreased dyspnea during exercise, enhanced performance of activities of daily living, and increased well-being.
References (27)
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Effect of oxygen on exercise ability in chronic respiratory insufficiency: use of portable apparatus
Lancet
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Oxygen relieves breathlessness in “pink puffers.”
Lancet
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Mechanisms of oxygen effects on exercise in patients with chronic obstructive pulmonary disease
Chest
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Relationship between improvement in exercise performance with supplemental oxygen and hypoxic ventilatory drive in patients with chronic airflow obstruction
Chest
(1989) - et al.
Effect of hyperoxia on gas exchange and lactate kinetics following exercise onset in non-hypoxemic COPD patients
Chest
(2002) Continuous or nocturnal oxygen therapy in hypoxemic chronic obstructive lung disease
Ann Intern Med
(1980)Long-term domiciliary oxygen therapy in chronic hypoxic cor pulmonale complicating chronic bronchitis and emphysema
Lancet
(1981)Coverage issues manual, durable medical equipment, 60–4, home use of oxygen
- et al.
Effects of breathing oxygen upon cardiac output, heart rate, ventilation, systemic and pulmonary blood pressure in patients with chronic lung disease
Clin Sci
(1963) - et al.
Exercise tolerance breathing a low density gas mixture, 35 per cent oxygen and air in patients with chronic obstructive bronchitis
Clin Sci
(1970)
Response to exercise in patients with chronic airway obstruction: II. Effects of breathing 40 per cent oxygen
Am Rev Respir Dis
Oxygen-assisted. exercise in chronic obstructive lung disease: the effect on exercise capacity and arterial blood gas tensions
Am Rev Respir Dis
Effect of oxygen on breathing during exercise in patients with chronic obstructive lung disease
Eur J Respir Dis
Cited by (47)
The effect of heated humidified nasal high flow oxygen supply on exercise tolerance in patients with interstitial lung disease: A pilot study
2021, Respiratory MedicineCitation Excerpt :A minimal expiratory positive pressure between 1.5 and 5.3 cmH2O was assured using adapted nasal cannulas. FiO2 was fixed at 0.5 based on previous studies in COPD [30,31] and ILD [28] patients during exercise. Subjects exercised on a computer-controlled electronically-braked cycle ergometer (Medisoft ergometer, Leeds, United Kingdom).
Oxygen supplementation increases the total work and muscle damage markers but reduces the inflammatory response in COPD patients
2020, Respiratory Physiology and NeurobiologyCitation Excerpt :Consistent with this, an increase in total work during exercise with O2-Suppl compared to that without O2-Suppl was observed in 100 % of the patients in the present study. Previous studies have shown that O2-Suppl is more efficient in patients with EID (Oliveira et al., 2012; Snider, 2002), however, this improvement in physical function can also occur in patients without EID (Oliveira et al., 2012; Richardson et al., 1999; Spielmanns et al., 2015). O2-Suppl with 40 % FIO2 has been shown to promote an increase in peak load (Watts) of 7.4 % and 21.1 % in non-desaturated and desaturated patients with COPD, respectively (Oliveira et al., 2012).
Effective bronchoscopic lung volume reduction accelerates exercise oxygen uptake kinetics in emphysema
2016, ChestCitation Excerpt :Novel treatment strategies aimed to increase peripheral O2 delivery (eg, supplemental oxygen or oral antioxidants),48,49 and/or decrease O2 needs (eg, nitrate supplementation)50 may prove to be of additional benefit with training to prevent or delay the onset of limb muscle fatigue.
Exercise oxygen flow titration methods in COPD patients with respiratory failure
2012, Respiratory MedicineCitation Excerpt :High oxygen flows are able to reduce minute ventilation and the respiratory rate for a given workload, improve ventilatory muscle function during exercise by postponing the onset of respiratory muscle fatigue and improving the capacity of the diaphragm to sustain work, increase oxygen delivery and its utilization by muscles during exercise, decrease dyspnea and improve endurance by directly reducing chemoreceptor activity.3 Furthermore, it has been confirmed that hyperoxia reduces dynamic hyperinflation,29 which is the main limiting factor of daily physical activity in COPD patients.13 An attractive alternative to oxygen-flow titration procedures might consist of the integration of sensors in the portable oxygen devices that would measure oxyhemoglobin saturation in real time and adjust the oxygen flow until reaching over 90% saturation levels at every moment and for each activity.
A randomised trial of domiciliary, ambulatory oxygen in patients with COPD and dyspnoea but without resting hypoxaemia
2011, ThoraxCitation Excerpt :Hyperoxia is believed to reduce dyspnoea during exercise by reducing ventilatory demand and delaying the onset of dynamic hyperinflation. Previous studies suggest that this may occur in a dose-dependent fashion, up to a fraction of inspired oxygen of 0.5 or a flow of 6 l/min of 100% oxygen.4 We chose a flow rate of 6 l/min in order to maximise this effect and because the lower flow rates used in previous studies may have provided inadequate relief from exercise-induced desaturation.8–10