Accu[O.sub.2] oximetry-driven oxygen-conserving device versus fixed-dose oxygen devices in stable COPD patients

• Published in: Respiratory care Vol. 56; no. 12; p. 1901
• Main Authors: Rice, Kathryn L, Schmidt, Matthew F, Buan, John S, Lebahn, Francene, Schwarzock, Ted K
• Format: Journal Article
• Language: English
• Published: Daedalus Enterprises, Inc 01.12.2011
• Subjects: Care and treatment; Diagnosis; Health aspects; Lung diseases, Obstructive; Methods; Oxygen equipment (Medical care); Oxygen therapy; United States
• ISSN: 0020-1324; 1943-3654
• DOI: 10.4187/respcare.01059

BACKGROUND: Because standard home oxygen ([O.sub.2]) systems deliver [O.sub.2] at fixed rates, these systems are not designed to ensure optimal oxygen delivery based on physiologic need. We tested the ability of the Accu[O.sub.2] (OptiSat Medical, Minneapolis, Minnesota), a portable, closed-loop, oximetry-driven, [O.sub.2]-conserving device to maintain [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] at ≥ 90%, compared to continuous- flow oxygen and a standard [O.sub.2]-conserving device (CR-50, Puritan-Bennett, Pleasanton, California). METHODS: We randomly assigned 28 patients who were on continuous home [O.sub.2] for COPD to use each of 3 [O.sub.2] delivery systems (continuous-flow [O.sub.2], CR-50, and Accu[O.sub.2]) for 8 hours a day, for 2 consecutive days, at home, at their current [O.sub.2] prescription. We recorded [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] and calculated the conservation ratio (duration of a given [O.sub.2] supply with an [O.sub.2]-conserving device compared to continuous-flow [O.sub.2]). RESULTS: Twenty-two patients completed all 3 study arms; 2 additional patients completed the Accu[O.sub.2] arm and the continuous-flow [O.sub.2] arm. The mean ± SD SpO was 92 ± 4% with continuous- flow [O.sub.2], 92 ± 4% with the CR-50, and 91 ± 2% with Accu[O.sub.2] (P = .006 for the Accu[O.sub.2] vs continuous-flow [O.sub.2], P = .03 for the Accu[O.sub.2] vs the CR-50). [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] variability was less with the Accu[O.sub.2] (P < .001 vs continuous-flow [O.sub.2] and vs the CR-50). The conservation ratios were 9.9 ± 7.3 for the Accu[O.sub.2] and 2.6 ± 1.0 for the CR-50 (P < .001). CONCLUSIONS: Compared to continuous-flow [O.sub.2] or the CR-50, the Accu[O.sub.2] maintained [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] closer to the target, and Accu[O.sub.2] had a higher conservation ratio than CR-50. Key words: COPD; long-term oxygen therapy; oxygen-conserving device; pulse oximetry. [Respir Care 2011;56(12):1901-1905]