The CPAP mode of ventilation allows:

• to recruit collapsed alveoles
• to restore a satisfactory level of functional residual capacity
• to improve gas exchange at the level of the alveolocapillary membrane
• to decrease pulmonary resistance
• to decrease the work of breathing
• to redistribute the alveolar liquid to the interstitial space in case of acute pulmonary oedema

The Boussignac CPAP and its manometer connector is a device for connection to a face mask with its 22 mm male connector, the crenellated upper part remaining open to the air.
This device comprises 2 lateral ports:

• the upper port is preconnected to a an extension tube (length 200 cm) for connection to an air or oxygen source
• the bottom port (colourless translucent) allows:

. controlling pressure (use manometer code 527.01),
. an additional oxygen supply if the gas administered to the patient via the upper port is air,
. CO2 monitoring.

The CPAP Boussignac set includes:

• 1 CPAP Boussignac with  a 200 cm long green extension tube and with a 50 cm long extension tube to connect the Boussignac CPAP to a manometer.
• 1 face mask (available in 4 sizes) :

. one “adolescent” mask code 5562.303*
. one “adult-small size” mask code 5562.403*
. one “adult-medium size” mask code 5562.503*
. one “adult-large size” mask code 5562.603*

• 1 fixation harness code. 5559.01

How it works:
The gases administered to the patient (air, air-oxygen mixture or pure oxygen) pass through the extension tube and arrive in a circular chamber where the gases can only escape into the central zone passing through 4 micro-channels. At that moment, the injection speed of the gases is greatly increased. Deflector at the exit site of the micro-channels eject the gases arriving at high speed towards the opposite wall.
The collision of gas molecules between themselves generates a turbulence which creates a virtual valve and simultaneously the speed of gases is transformed in pressure. This pressure depends directly on the flowrate: if the flowrate (the amount of gas injected) is increased, the pressure will increase; if the flowrate is decreased, the pressure will decrease.

N.B. It is possible to connect the Boussignac CPAP to an endotracheal tube or to a tracheostomy tube using the adaptor code 555.01 together with an artificial nose such as Hygroflux code 501.01.

*Codes 5562.303/403/503/603: Vanilla scented mask.