Patient interface with a heat and moisture exchanger
A patient interface is disclosed. The patient interface has a plenum chamber and a seal forming structure arranged to form a seal with a region of the patient's face surrounding an entrance to the patient's airways. The patient interface further comprises a heat and moisture exchanger (HME) located within the plenum chamber. The HME comprises a flexible heat and moisture exchange material and a retaining structure formed from a pliable material provided around an outer perimeter of the heat and moisture exchange material. The retaining structure comprises at least one snap fit feature configured to engage, in use, at least one complementary snap fit feature provided to an interior of the plenum chamber; and/or the retaining structure is an interference fit with an interior surface of the plenum chamber. Also disclosed is an HME comprising a flexible heat and moisture exchange material and a retaining structure formed from a thermoplastic.
1 . A patient interface comprising:
a plenum chamber pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum chamber including a plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by a patient,
a seal-forming structure constructed and arranged to form a seal with a region of the patient's face surrounding an entrance to the patient's airways, said seal-forming structure having a hole therein such that the flow of air at said therapeutic pressure is delivered to at least an entrance to the patient's nares, the seal-forming structure constructed and arranged to maintain said therapeutic pressure in the plenum chamber throughout the patient's respiratory cycle in use;
a positioning and stabilising structure to provide a force to hold the seal-forming structure in a therapeutically effective position on the patient's head, and
a vent structure to allow a continuous flow of gases exhaled by the patient from an interior of the plenum chamber to ambient, said vent structure being sized and shaped to maintain the therapeutic pressure in the plenum chamber in use;
wherein the patient interface is configured to allow the patient to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient interface is configured to leave the patient's mouth uncovered; and
wherein patient interface comprises a flexible heat and moisture exchanger (HME) located within the plenum chamber, the HME comprising a flexible heat and moisture exchange material and a retaining structure formed from a pliable material provided around an outer perimeter of the heat and moisture exchange material,
wherein: the interior of the plenum chamber comprises at least one snap fit feature, and the retaining structure comprises at least one complementary snap fit feature comprising a rib, the at least one complementary snap fit feature being configured to engage, in use, the at least one snap fit feature located on the interior of the plenum chamber.
2 . The patient interface of claim 1 , wherein the heat and moisture exchange material comprises a foam.
3 . The patient interface of claim 1 , wherein the heat and moisture exchange material comprises a non-woven material.
4 . The patient interface of claim 1 , wherein the retaining structure is formed from a flexible thermoplastic.
5 . The patient interface of claim 4 , wherein the retaining structure is formed by overmoulding.
6 . The patient interface of claim 1 , wherein the plenum chamber is formed, at least in part, from a flexible material.
7 . The patient interface of claim 1 , wherein the heat and moisture exchange material has a patient facing side and a non patient facing side, and wherein the patient facing side of the heat and moisture exchange material is concave.
8 . The patient interface of claim 7 , wherein the retaining structure comprises a shaping member which extends across the patient facing side of the heat and moisture exchange material, wherein the shaping member is configured to impart the concave shape to the patient facing side of the heat and moisture exchange material.
9 . The patient interface of claim 1 , wherein the patient interface is configured to allow air to flow from the inlet port to the vent structure without passing through the HME.
10 . The patient interface of claim 1 , wherein the retaining structure comprises a snap fit feature which comprises a channel which extends at least partially around the outer perimeter of the retaining structure.
11 . The patient interface of claim 10 , wherein the channel extends around the entire outer perimeter of the retaining structure.
12 . The patient interface of claim 1 , wherein the rib extends at least partially around the outer perimeter of the retaining structure.
13 . The patient interface of claim 1 , wherein the HME is configured to provide at least 10 mg/L humidification.
14 . A patient interface comprising:
a plenum chamber pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum chamber including a plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by a patient,
a seal-forming structure constructed and arranged to form a seal with a region of the patient's face surrounding an entrance to the patient's airways, said seal-forming structure having a hole therein such that the flow of air at said therapeutic pressure is delivered to at least an entrance to the patient's nares, the seal-forming structure constructed and arranged to maintain said therapeutic pressure in the plenum chamber throughout the patient's respiratory cycle in use;
a positioning and stabilising structure to provide a force to hold the seal-forming structure in a therapeutically effective position on the patient's head, and
a vent structure to allow a continuous flow of gases exhaled by the patient from an interior of the plenum chamber to ambient, said vent structure being sized and shaped to maintain the therapeutic pressure in the plenum chamber in use;
wherein the patient interface is configured to allow the patient to breath from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient interface is configured to leave the patient's mouth uncovered; and
wherein patient interface comprises a flexible heat and moisture exchanger (HME) located within the plenum chamber, the HME comprising a flexible heat and moisture exchange material and a retaining structure formed from a pliable material provided around an outer perimeter of the heat and moisture exchange material,
wherein the interior of the plenum comprises a rib; wherein the channel is configured to engage the rib of the interior of the plenum chamber in a snap fit.
15 . The patient interface of claim 14 , wherein the patient interface is configured to allow air to flow from the inlet port to the vent structure without passing through the HME.