Related Experiment Video
Updated: Jan 19, 2026
Cerebral Blood Oxygenation Measurement Based on Oxygen-dependent Quenching of Phosphorescence
Published on: May 4, 2011
Oropharyngeal Oxygen Concentration Is Dependent on the Oxygen Mask System and Sampling Location
N David Yanez1, Alexander Y Fu2, Miriam M Treggiari3
1Division of Biostatistics, School of Public Health, Oregon Health and Science University, Portland, Oregon. yanezn@ohsu.edu.
Background:
Numerous oxygen delivery systems are used to treat hypoxemia. It is unknown if FIO at the lips predicts oropharyngeal FIO for various oxygen mask systems. We tested whether FIO measurements differed between the lips and oropharynx, and whether this difference depends on the mask system.
Methods:
Ten healthy volunteers had one sampling catheter positioned at the lips and another catheter in the oropharynx. FIO was sampled at each location while the subjects breathed normal tidal volumes with oxygen at 15 L/min via 4 delivery devices: a simple mask, a non-rebreather mask, a face mask with a diffuser that concentrates and directs O2 toward the mouth and nose (mask with diffuser), and a closed mask with a Jackson-Rees circuit. Data were analyzed by using a linear mixed model to account for subject crossover in the repeated measures design.
Results:
FIO levels differed significantly for the 4 delivery mask systems (P < .001) and by sampling catheter location (P < .001). Differences in mean FIO between the lips and the oropharynx were observed for the mask with diffuser (difference 0.30, 95% CI 0.25-0.36; P < .001), and non-rebreather mask (difference 0.09, 95% CI 0.04-0.15; P = .001). The mean FIO at the oropharynx was highest for the closed mask (0.97, 95% CI 0.92-1.00), followed by the non-rebreather mask (0.76, 95% CI 0.72-0.81), simple mask (0.62, 95% CI 0.58-0.67), and the mask with diffuser (0.51, 95% CI 0.46-0.56). At the lips, the mean FIO was highest for the closed mask (0.97, 95% CI 0.92-1.00), followed by the non-rebreather mask (0.86, 95% CI 0.81- 0.90), OxyMask (0.81, 95% CI 0.76-0.86), and simple mask (0.67, 95% CI 0.62-0.71).
Conclusions:
With high oxygen flows and normal tidal volume breathing, FIO measurements obtained at the oropharynx or at the lips depended on the device used, with the mask with diffuser showing the most significant discrepancies. FIO measures at the oropharynx and the lips were only consistent for the closed mask system. (ClinicalTrials.gov registration NCT02523586.).
Related Concept Videos
08:58Cerebral Blood Oxygenation Measurement Based on Oxygen-dependent Quenching of Phosphorescence
01:30Administering Oxygen by Mask
Administering oxygen by mask is a common nursing intervention that provides supplemental oxygen to patients with respiratory distress or chronic lung conditions. This procedure involves delivering oxygen at a specified rate through a face mask connected to an oxygen source.
Equipment
The equipment necessary for this procedure includes:
01:16Oxygen Delivering System II: Venturi Mask and Transtracheal Oxygen
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...
01:26Oxygen Delivering System I: Nasal Cannula and Face Mask
Nasal Cannula
A nasal cannula is a lightweight tube split at one end into two prongs and placed in the nostrils. It is typically used to deliver low to medium levels of oxygen.
Suggested flow rate: The suggested flow rate for a nasal cannula typically ranges between 1 and 6 L/min.
Oxygen percentage setting:...
10:24Evaluation of Intracellular Location of Reactive Oxygen Species in Solea Senegalensis Spermatozoa
13:17Manufacture of Concentrated, Lipid-based Oxygen Microbubble Emulsions by High Shear Homogenization and Serial Concentration