Introduction: Long-term oxygen therapy (LTOT) is the only treatment that improves prognosis in patients with chronic respiratory failure in the course of chronic obstructive pulmonary disease (COPD). This effect depends on the duration of oxygen use during the day and night. The aim of this study was to evaluate the daily use of oxygen concentrator and to analyze factors that promote patient compliance.
Material and methods: The study enrolled patients seen at the Long-Term Oxygen Therapy Center of the Department of Internal Medicine, Pneumology and Allergology, Medical University of Warsaw, Poland. Qualification for LTOT was in accordance with the guidelines of the Polish Respiratory Society and the European Respiratory Society (ERS). All patients were instructed to use oxygen therapy for at least 15 hours a day using a stationary oxygen concentrator. The duration of oxygen concentrator use was evaluated on the basis of the concentrator counter reading performed by visiting nurses. The visits were run on the monthly basis.
Results: The study group involved 30 subjects (77% of COPD patients). The mean age was 67 ± 9 years, mean FEV
1 was 46 ± 18% predicted, RV/TLC was 64 ± 16% and PaO
2 was 50 ± 6 mm Hg. The mean duration of the daily oxygen therapy for the entire study group was 12.5 ± 4.6 hours. Eleven (37%) patients complied with the treatment during the follow-up period with the mean duration of daily oxygen therapy 17.4 ± 2.6 hours. The mean oxygen therapy use in the non-compliant group of patients averaged 9.6 ± 2.7 hours. We found that highest percentage of patients (48%) used oxygen for an appropriate period of time in the # first month of the treatment. The second month the number decreased to about 30% and remained at this level until the end of the follow-up period. The analysis of the COPD patients showed that in case of the compliant subjects the values of total lung capacity (TLC) (100 ± 19% predicted v. 152 ± 36% predicted,
p = 0.001) and PaCO
2 (38 ± 6 mm Hg v. 47 ± 8 mm Hg,
p < 0.05) were significantly lower in comparison to the group of patients who used the oxygen therapy for less than 15 hours a day. Fourteen (47%) patients reported a considerable increase in electricity consumption and seven (23%) patients complained about the noise of the oxygen concentrator. The daily oxygen use of this group was significantly lower in comparison to the patients who were not annoyed with the sound of the concentrator (9.0 ± 3.7 h/24 h v. 13.5 ± 4.4 h/24 h,
p = 0.02).
Conclusions: Our study show that the patients’ compliance was the highest during the first month of the treatment only, and that the monthly home visit did not influence the patients’ self-discipline to use LTOT properly. The use of an alternative source of oxygen, such as liquid oxygen, which would not generate any noise or electricity consumption, may positively influence the patient’s compliance.
Full article