This page begins with an explanation of CPAP, followed by mask-CPAP and Boussignac CPAP.
CPAP is continuous positive airway pressure. This means that while the patient breathes, a positive pressure is present during both inspiration and expiration. Support by CPAP can be either invasive (i.e. endotracheal tube, laryngeal mask or tracheal cannula) or non-invasive with various sorts of face masks.
How does CPAP work
By administering CPAP, the functional residual capacity of the lungs is increased as the airways distend as a result of the positive pressure. Thus, collapsed or poorly ventilated alveoli will open. CPAP also prevents alveoli that have been opened from collapsing again. CPAP improves the pO2 in the majority of patients.
Please view the following examples:
- Disturbed diffusion of oxygen as a result of alveolar fluid. The diffusion of oxygen is more sensitive to pulmonary edema than the diffusion of carbon dioxide.
- Alveoli are opened by CPAP. Fluid is distributed over a greater surface with improved diffusion as a result.
What is mask CPAP
Mask CPAP is the clinical application of continuous positive airway pressure with the use of a mask that (partially) covers the face. The mask contains a ring that can be insufflated so the leakage of air between the mask and the patient's face is minimized. The face mask is a closed system that can be used to apply positive airway pressure in a non-invasive way.
What is Boussignac mask-CPAP
The Boussignac mask-CPAP system is a disposable CPAP-system without moving parts. Positive pressure is generated by four tiny gas jets that emerge from four microchannels into a hollow tube. This tube with a length of 5 cm and a weight of only 10g generates more pressure (CPAP) if the gas-flow is higher. To generate a Boussignac CPAP at a pressure of 5 cm H2O, an oxygen flow of 15 L/min is applied. The system provides an FiO2 of at least 80%.
The Boussignac system is directly connected to the face mask, which comes in four different sizes, and is connected to an oxygen tube (or air/oxygen).