A pilot study comparing 2 oxygen delivery methods for patients' comfort and administration of oxygen

Respir Care. 2014 Aug;59(8):1191-8. doi: 10.4187/respcare.02937. Epub 2013 Dec 24.


Background: The traditional oxygen delivery methods for oxygen therapy are continuous flow oxygen (CFO) and demand oxygen delivery (DOD); however, oxygen waste is considerable in CFO, while DOD is uncomfortable for patients. Synchronized DOD (SDOD), which was designed to overcome the drawbacks of both CFO and DOD, supplies oxygen according to the patient's breathing pattern and the desired oxygen saving. This study was conducted to examine the overall performance of SDOD in terms of oxygen saturation (SpO2 ), patients' comfort, and oxygen saving ratio (SR).

Methods: Study subjects were patients who required oxygen for COPD or pneumonia. Patients received oxygen through nasal prongs by CFO and SDOD for 30 min each. SpO2 was measured every 10 min by pulse oximetry, and subjects recorded their level of comfort after 30 min. The flow of discharged oxygen was recorded to calculate SR.

Results: Ten subjects (median age, 68 y; range, 56-86 y) were enrolled. The SpO2 of patients during SDOD (97 ± 2%) was similar to that during CFO (96 ± 3%) with no statistically significant difference (P = .53). Subjects reported SDOD to be more comfortable than CFO. The comfort score of subjects treated with SDOD was 7.05 ± 2.07 (0: very uncomfortable, 10: very comfortable); this was significantly higher (P = .02) than the comfort score (5.20 ± 1.83) of subjects treated with CFO. The SR values set by clinicians were very similar to calculated SR values.

Conclusions: SDOD appears to be more suitable for oxygen therapy than CFO when considering SpO2 , patients' comfort, and SR.

Keywords: SpO2; continuous flow oxygen; discomfort; oxygen therapy; saving ratio; synchronized demand oxygen delivery.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Female
  • Humans
  • Lung Diseases, Interstitial / therapy*
  • Male
  • Middle Aged
  • Oxygen / administration & dosage*
  • Oxygen Inhalation Therapy / instrumentation*
  • Patient Satisfaction
  • Pilot Projects
  • Pneumonia / therapy*
  • Pulmonary Disease, Chronic Obstructive / therapy*
  • Respiration


  • Oxygen