Objectives To describe the use, effectiveness and tolerance of high‐flow oxygen therapy in dyspnoeic dogs. Materials and Methods Prospectively, dogs in acute respiratory distress admitted to an intensive care unit between January and May 2018 that failed to respond to nasal oxygen therapy and medical stabilisation after 30 minutes were transitioned to high‐flow oxygen therapy. High‐flow oxygen therapy, delivered an inspired oxygen fraction of 100% using an air/oxygen blender, active humidifier, single warmed tube and specific nasal cannula. Respiratory rate, pulse oximetry (SpO2), heart rate and a tolerance score were assessed every 15 minutes from T0 (under nasal oxygen) to 1 hour (T60), and PaO2 and PaCO2 at T0 and T60. Complications were recorded for each dog. Results Eleven dogs were included. At T60, PaO2, flow rate and SpO2 were significantly greater than at T0 (171 ± 123 versus 73 ± 24 mmHg; P=0.015; 18 ±12 L/minute versus 3.2 ± 2.0 L/minute, P<0.01; 97.7 ±2.3% versus 91.6 ±7.2%, P=0.03, respectively). There was no significant difference in PaCO2, respiratory rate or heart rate between T0 and T60. Tolerance was excellent, and there were no complications. Clinical Significance High‐flow oxygen therapy improves markers of oxygenation in dyspnoeic dogs and is an effective means to deliver oxygen with comfort and minimal complications.

Objectives To prospectively describe the impact of gas flow rate and temperature on dog's tolerance of high‐flow nasal oxygen therapy during recovery from anaesthesia, hypothesizing that higher flow rates and temperatures will decrease tolerance. Materials and Methods Twelve non‐dyspnoeic client‐owned dogs recovering from general anaesthesia were included in this study. After extubation, a nasal cannula was positioned and high‐flow nasal oxygen therapy was initiated. Two flow rates (two or four time the theoretical minute ventilation: HF2 and HF4), each of them combined with two temperatures (31 and 37°C: T31 and T37), were randomly applied (four conditions per dog). For each condition, cardiovascular and respiratory parameters (heart rate, respiratory rate, systolic arterial blood pressure and pulse oximeter oxygen saturation), sedation score and tolerance score were recorded at initiation (T0) and after 10 minutes of accommodation (T10). Results Sedation scores were not significantly different between the four conditions. Cardiovascular and respiratory parameters were not significantly different between any condition at both T0 and T10. Tolerance scores were good and not significantly different between any flow rate or temperature (HF2‐T31: 4 (2‐4), HF4‐T31: 4 (2‐4), HF2‐T37: 4 (2‐4), HF4‐T37: 4 (1‐4)). Clinical Significance The gas flow rates and temperatures studied have no impact on tolerance during the recovery period of non‐dyspnoeic dogs, and high‐flow nasal cannula is well tolerated. Further studies are required to confirm these results in dyspnoeic dogs.