From the Guidelines
The AIRVO device, a high-flow nasal cannula system, typically requires setting three main parameters: flow rate, temperature, and oxygen percentage (FiO2), with initial settings for adults being a flow rate of 30-60 L/min, temperature of 37°C, and FiO2 based on the patient's oxygen needs (21-100%) 1.
Key Parameters for Setting Up Airvo
- Flow rate: The initial flow rate for adults should be between 30-60 L/min, commonly starting at 40 L/min, as suggested by recent guidelines on the use of high-flow nasal oxygen in hospitalized patients 1.
- Temperature: The temperature should be set at 37°C, which is body temperature, to ensure comfort and effectiveness of the therapy.
- Oxygen percentage (FiO2): This should be adjusted based on the patient's oxygen needs, ranging from 21% to 100%.
Adjusting Settings Based on Patient Response
These settings should be adjusted based on the patient's response, comfort, and oxygen saturation levels. The AIRVO system works by delivering heated, humidified air/oxygen at high flow rates, which helps wash out anatomical dead space, provides some positive pressure, reduces work of breathing, and delivers consistent FiO2 1. Regular assessment of the patient's respiratory status is essential to determine if the therapy is effective or if settings need adjustment.
Considerations for Pediatric Patients
For pediatric patients, lower flow rates are used, typically 1-2 L/kg/min up to a maximum of 25 L/min. The temperature can be reduced to 34°C if the patient finds 37°C uncomfortable. It's crucial to monitor the patient's comfort and response to the therapy closely and adjust the settings as necessary to ensure the best possible outcomes.
From the Research
Setting Parameters for Airvo
The setting parameters for Airvo, a high-flow nasal oxygen therapy device, can be understood through various studies that have evaluated its performance and compared it with other similar devices.
- The Airvo 2 device has been tested with different flow rates and temperatures to assess its humidification performance 2, 3.
- In one study, the dew point temperature was set at 31,34, and 37°C, and the flow was set from 20 L/min up to its maximum set limit at a gradient of 5 L/min or 10 L/min 2.
- Another study evaluated the Airvo 2 device at flow rates of 20,40, and 50 L/min, with the outlet-chamber temperature set at 37°C 3.
- The performance of the Airvo 2 device has also been characterized in combination with the Aerogen Solo vibrating mesh nebuliser for in-line aerosol therapy during high-flow nasal oxygen therapy, with gas flow rate and cannula size varied across the full operating range recommended by the manufacturer 4.
- A bench study assessed the hygrometric performances of different high-flow nasal cannula devices, including the Airvo 2, according to flow, ambient temperature, and other available settings 5.
Key Findings
- The actual dew point temperature of the delivered gas from the Airvo 2 device increased with the increase of set-flow under each set-DP, but decreased when the set-flow was greater than 60 L/min 2.
- The absolute humidity of the inspired gas delivered by the Airvo 2 device was found to be higher at 40 and 50 L/min of flow than at 20 L/min 3.
- The Airvo 2 device can provide the nominal humidity at 37°C, and may be more suitable for tracheotomy patients 2.
- Gas flow rate was found to be the primary parameter affecting aerosol delivery during high-flow nasal oxygen therapy with the Airvo 2 device 4.
- The hygrometric performance of the Airvo 2 device was found to be satisfactory with respect to breathing comfort, with a mean absolute humidity of 42.2 ± 3.1 mg H2O/L 5.