Continuous domiciliary oxygen therapy in Zaragoza: a cross-sectional home study

Abstract

To assess use of long-term domiciliary oxygen therapy (LDOT) in Saragossa by means of home interviews. We conducted a cross-sectional study of patients undergoing LDOT, interviewing 312 of the 614 patients who used O2 at home in January 1993 (103/100,000 h). Health care workers visited the patients at home and collected all available information related to indications, pattern of use of O2 and complementary tests done. The interviewer also took spirometric readings, SaO2 readings breathing room air and after 30 min breathing O2, and administered a quality of life questionnaire (only to patients with pneumopathies). All patients selected were assessed; 195 (62.5%) suffered from chronic obstructive pulmonary disease (COPD), 33 (10.6%) from asthma, 31 (9.9%) from other pneumopathies, and 53 (17%) from a variety of conditions that were not primarily bronchopulmonary. Thirty-six (11.5%) were active smokers. Only 101 of the 184 patients for whom arterial gasometric readings were available met the criteria for prescribing LDOT. SaO2 without O2 was > or = 92% in 89 (28.5%) patients and > or = 90% in 193 (61.8%). Only 96 (31%) patients reported using O2 more than 15 hours/day and there was a weak inverse relation (p = 0.04) between hours of use and FEV1 in the COPD group. Quality of life for patients with pneumophaties depended entirely on degree of lung function deterioration and was unrelated to use of O2. The rate of use of LDOT Saragossa is one of the highest in Spain. In an estimated 28.5-46% of cases, the indications are inappropriate, mainly due to infrequent use of arterial gas measurement and the prescription of LDOT for patients without COPD. This situation largely explains why patients hardly ever use LDOT on a daily basis.