Patient interface and non-invasive positive pressure ventilating method

Abstract

A patient interface for use in delivering a flow of breathable gas to an airway of a patient includes a first seal adapted to contact the patient's face and seal a first space between the patient interface and the patient's face at a first positive pressure; and a second seal adapted to contact the patient's face and seal a second space between the patient interface and the patient's face at a second positive pressure. The first seal also seals the first space from the second space. A leak reducing element may be provided on a seal to reduce and/or diffuse leakage of gas. A vacuum line configured to create a negative pressure may be provided in the second space to remove any gas leaking from the first space to the second space. A seal may be connected to a conduit for delivering the flow of gas that is incorporated into a frame of the patient interface. The seal may be inflatable by the flow of breathable gas to pressurize the seal against the patient's face and include a vent that directs the flow of breathable gas to a space between the patient interface and the patient's face. A cuff may be provided over the seal in the nasal bridge region to direct any leakage of the gas flow from the seal in the nasal bridge region in a direction away from the patient's eyes.

What is claimed is: 
     
         1 . A patient interface for use in delivering a flow of breathable gas to an airway of a patient, the patient interface comprising:
 a first seal adapted to contact the patient's face and seal a first space between the patient interface and the patient's face at a first positive pressure; and   a second seal adapted to contact the patient's face and seal a second space between the patient interface and the patient's face at a second positive pressure, the second space surrounding the first space, wherein the first seal is configured to seal the first space from the second space and prevent or reduce leakage of gas to the second space and the second seal is configured to seal the second space from ambient and prevent or reduce leakage of gas to the ambient.   
     
     
         2 . A patient interface according to  claim 1 , wherein a maximum sealing pressure of the first seal is greater than or equal to a maximum sealing pressure of the second seal. 
     
     
         3 . A patient interface according to  claim 1 , wherein a maximum sealing pressure of the first seal is less than or equal to a maximum sealing pressure of the second seal. 
     
     
         4 . A patient interface according to  claim 1 , further comprising a vent in the first space. 
     
     
         5 . A patient interface according to  claim 1 , further comprising a vent in the second space. 
     
     
         6 . A patient interface according to  claim 1 , wherein the first seal is formed of a flexible material non-permeable to the breathable gas. 
     
     
         7 . A patient interface according to  claim 1 , wherein the second seal is formed of a flexible material non-permeable to the breathable gas. 
     
     
         8 . A patient interface according to  claim 1 , wherein the first seal is formed of porous material. 
     
     
         9 . A patient interface according to  claim 1 , wherein the first seal is made of more than one material. 
     
     
         10 . A patient interface according to  claim 9 , wherein at least one of materials comprises at least one porous section. 
     
     
         11 . A patient interface according to  claim 1 , further comprising a nozzle that circulates a leak flow of the breathable gas from the first space to the second space back to the first space. 
     
     
         12 . A CPAP apparatus comprising a patient interface according to  claim 1 . 
     
     
         13 . A BiPAP apparatus comprising a patient interface according to  claim 1 . 
     
     
         14 . A patient interface for use in delivering a flow of breathable gas to an airway of a patient, the patient interface comprising:
 a seal adapted to contact the patient's face and seal a space between the patient interface and the patient's face at a positive pressure; and   a leak reducing means provided on the seal for reducing leakage of gas from the space.   
     
     
         15 . A patient interface according to  claim 14 , wherein the seal is formed of a flexible material non-permeable to the breathable gas. 
     
     
         16 . A patient interface according to  claim 14 , wherein the leak reducing means comprises a porous layer on the seal and adapted to contact the patient's face. 
     
     
         17 . A patient interface according to  claim 16 , wherein the porous layer is provided outside of the space. 
     
     
         18 . A patient interface according to  claim 14 , wherein the seal is formed of a flexible material non-permeable to the breathable gas and a porous layer in parallel. 
     
     
         19 . A patient interface according to  claim 18 , wherein the porous layer is adapted to contact the patient's face. 
     
     
         20 . A patient interface according to  claim 14 , wherein the leak reducing means diffuses the leakage of the gas from the space.