Chest
Clinical InvestigationsComparison of Six Oxygen Delivery Systems for COPD Patients at Rest and during Exercise
Section snippets
Methods
Ten individuals with COPD were entered into the study. Entry criteria included an FEV1/FVC ratio of less than 60 percent and a period of stability on chronic home oxygen after having met the NOTT criteria for home oxygen use.3 The protocol was explained to each subject and they signed an informed consent as approved by the Institutional Review Board.
All individuals who entered the study came to the pulmonary research laboratory in the morning. They were allowed to rest in a chair while
Results
The initial resting SaO2 was similar with each of the six oxygen delivery systems evaluated (Table 2). This supports each manufacturers claim that their recommended settings did approximate the same levels obtained using continuous O2 flow by nasal cannula at rest. Also, resting heart rates were similar in all groups (p>0.05).
During exercise, several of the parameters varied between the devices. Mean values of the average SaO2 recorded during exercise with each device can be seen in Table 3.
Discussion
The electronic devices evaluated in the study utilize two different strategies in reducing the amount of oxygen needed. One of these is to provide a “burst” of oxygen at the onset of inspiration. If the number of breaths increase, the number of “bursts” increase, as does the amount of oxygen delivered. Thus, if the respiratory rate goes from 15 to 30/min, the number of oxygen boluses would double, thus effectively increasing the oxygen delivery. Devices A and C fall into this category. Oxygen
References (19)
- et al.
Oxygen conservation and oxygen conserving devices in chronic lung disease—a review
Chest
(1987) - et al.
A new oxygen cannula system using intermittent-demand nasal flow
Chest
(1978) - et al.
A demand valve conserves oxygen in subjects with chronic obstructive pulmonary disease
Chest
(1984) - et al.
Low-concentration oxygen therapy via a demand oxygen delivery system
Chest
(1985) - et al.
Performance of a demand oxygen saver system during rest, exercise, and sleep in hypoxemic patients
Chest
(1988) - et al.
Demand oxygen delivery during exercise
Chest
(1987) - et al.
The role of long-term continuous oxygen administration in patients with chronic airway obstruction with hypoxemia
Ann Intern Med
(1967) Report of the Medical Research Council Working Party. Long term domiciliary oxygen therapy in chronic hypoxic cor pulmonale complicating chronic bronchitis and emphysema
Lancet
(1981)Continuous or nocturnal oxygen therapy in hypoxemic chronic obstructive lung disease: a clinical trial
Ann Intern Med
(1980)
Cited by (38)
Clinician Strategies to Improve the Care of Patients Using Supplemental Oxygen
2019, ChestCitation Excerpt :One ILD study found no differences between a POC set on PD at 6 compared with a portable compressed gas tank set at CF at 5 L/min.47 Others found that PD was not comparable with CF systems in patients with COPD,48,49 and that CF provided greater volumes of oxygen per breath compared with PD in a human airway model.50 Many patients with ILD have a rapid shallow breathing pattern with exertion that may not consistently trigger a PD system.
Comparison of supplemental oxygen delivery by continuous versus demand based flow systems in hypoxemic COPD patients – A randomized, single-blinded cross-over study
2019, Respiratory MedicineCitation Excerpt :Up to now there are only few studies that compared DODS and CF oxygen devices and results are heterogeneous. Two studies found that DODS devices are inferior to maintain oxygen saturation compared to CF devices in COPD patients during exercise [16,17] while other studies found no relevant differences concerning the oxygen saturation during exercise [14,18–22]. These studies used the 6- or 12-minute walk test, an incremental shuttle walk test or treadmill walking for exercise.
Oxygen-conserving devices: A forgotten resource
2007, Archivos de BronconeumologiaComparison of four demand oxygen delivery systems at rest and during exercise for chronic obstructive pulmonary disease
2004, Respiratory MedicineCitation Excerpt :Evaluations of DODS efficacy during exercise testing have yielded conflicting results. Most studies found that oxygenation was similar with DODS and CFO in COPD patients.4,6,11,13–16 Carter et al investigated DODS in patients with restrictive lung disease (pulmonary fibrosis) and found that efficacy was good during rest and exercise, despite severe hypoxemia, high respiratory rates, and high inspiration over expiration ratios.17
Variability in performance of timed walk tests in pulmonary rehabilitation programs
2000, ChestCitation Excerpt :Most investigations have focused on how use of these devices influenced oxygenation at rest and with exercise. Only one study12 was found that evaluated walk distances. Ten patients with COPD completed six 12-min walks while using continuous-flow oxygen and five different intermittent-flow devices.
Supported by a grant from DeVilbiss Corporation, Somerset, Pa.
Dr. Braun is a recipient of the Preventive Pulmonary Academic Award from the National Institutes of Health.