Currow, D.C., Agar, M., Smith, J., & Abernethy, A.P. (2009). Does palliative home oxygen improve dyspnoea? A consecutive cohort study. Palliative Medicine, 23(4), 309-316.

The objective of the study is to identify the benefit of home oxygen therapy on breathlessness within a palliative care program.

Data were collected (from face-to-face clinical encounters) from a consecutive cohort of 5,862 patients seen by a regional community palliative care program. Patients who were prescribed home oxygen concentrators by referral to palliative care for symptomatic breathlessness were the population of interest. Breathlessness was assessed before and one week after oxygen prescription and before and two weeks after oxygen prescription as a way to explore benefits of home oxygen on an extended time frame.

Four hundred and thirteen patients were included for analysis and were found to have data collection points during the week before and at least one week after home oxygen prescription, and 230 comprised available breathlessness scores during the week before and at least two weeks after home oxygen prescription. The average age was 69.69 years, with a median age of 72 years and a range of 0-108 years. The sample was comprised of 2,552 (43.4%) females and 3,310 (56.6%) males. Of the sample, 5,386 (91.9%) identified with cancer diagnoses. Of the 413 patients included for analysis, 384 (93.1%) identified cancer diagnoses as their “life-limiting illness.\" Patients were prescribed home oxygen concentrators after referral to palliative care for symptomatic breathlessness.

The study was conducted in an inpatient setting at Silver Chain Hospice Care Service (SPHCS), a regional community palliative care program covering all the metropolitan area of Perth, Western Australia.

Descriptive, retrospective

Symptom Assessment Scale (SAS)-0-10 scale, although the anchors for each end of the scale for dyspnea were not identified

No significant improvement in SAS was observed one week after oxygen prescriptions (mean = 5.1, SD = 2.6, median = 5, range = 0-10, P value = 0.28). Where data were available for 230 individuals on home oxygen therapy, mean SAS dyspnea score was 5.4 (SD = 2.5, median = 4, range = 0-10), and no significant improvement in breathlessness scores was noted two weeks after use of home oxygen (mean = 5.2, SD = 2.5, median = 5, range = 0-10, P = 0.35). Sub-group analysis based on primary underlying diagnosis associated with breathlessness for people prescribed home oxygen showed no remarkable difference among individual response rates.

No significant clinical improvement in breathlessness was observed among this palliative care population.

The study had no group without oxygen for comparison. Pulse oximetry and dyspnea rating were not consistently measured after application of oxygen therapy, allowing only for assumed or indeterminable benefits of oxygen therapy. Authors reported that the sample size as too small for the differences in the primary cause of breathlessness to be fully explored. Generalizability was broadly reflective of palliative care patients admitted on a referral basis in “resource-rich” community settings and may not reflect the experience of individuals not referred for symptom management support. The post-hoc analysis design presents limitations in data selected to report and the use of a uni-dimensional measure of breathlessness that may not reflect the complete experience or distress the symptom causes in some individuals.

More data and studies regarding the symptomatic benefits of home oxygen therapy and the relationship between hypoxemia, breathlessness, changes in functional status, and the way in which oxygen is prescribed are needed.