Researchers enrolled 20 health dogs of mixed sex and breed in a randomized crossover study to compare face-mask oxygen supplementation to flow-by oxygen supplementation. The latter proved more effective.
Source: Taylor & Francis Online/New Zealand Veterinary Journal, Volume 67, 2019. Link. “Oxygen supplementation delivered using a face mask was more effective at increasing PaO2 than flow-by oxygen supplementation. Flow-by oxygen supplementation at a distance of 2 cm from the nose may be a suitable alternative when the use of a face mask is not tolerated by the patient.