EP-4736919-A2 - PATIENT INTERFACE

EP4736919A2EP 4736919 A2EP4736919 A2EP 4736919A2EP-4736919-A2

Abstract

The disclosure relates to a patient interface for non-invasive ventilation. The patient interface is configured to seal about the mouth and nares of a patient and includes an outer wall defining an interior volume which includes a first chamber having one or more oral openings to communicate gas with the mouth and a second chamber having one or more nare openings to communicate gas with the nares. The patient interface further includes a dividing wall that separates the first chamber from the second chamber. The patient interface further includes one or more flow directors which enable gas to flow into the second chamber from the first chamber or into the first chamber from the second chamber. The one or more flow directors are configured to direct the gas flow through the one or more nare openings.

Inventors

GORDON, JAMES ALEXANDER
GRAHAM, Ryan Anthony
VAN SCHALKWYK, Andre
Zoellner, Sascha Kristopher
NIHOTTE, Joseph Jules
PERERA, Ashani Melisha
GAO, Vicky Dan
DUTHIE, NEIL GRAY
SHAHRI, Saachi
STRAUSS, Frederic Walter Williamson
WHARMBY, Christopher

Assignees

Fisher & Paykel Healthcare Limited

Dates

Publication Date: 20260506
Application Date: 20220112

Claims (15)

A non-invasive patient interface which is configured to seal about the mouth and nares of a patient, the patient interface including: an outer wall defining an interior volume of the patient interface, the outer wall having one or more oral openings which communicate gas with the mouth and one or more nare openings which communicate gas with the nares; a dividing wall that separates the interior volume into a first chamber having the one or more oral openings and a second chamber having the one or more nare openings; and wherein the dividing wall includes one flow director which enables gas to flow into the second chamber from the first chamber and the flow director is configured to cause one-way flushing of dead space in the nasal cavity by a stream of respiratory gas flowing in one nostril and out the other nostril and the flow director is off-set laterally from a mid-plane between lateral sides of the patient interface, having regard to an upright orientation of the patient interface, and is configured to deliver a flow of respiratory gas to one nare.
The patient interface defined in claim 1, wherein the one flow director is configured to deliver an accelerated flow of respiratory gas to create a flushing flow.
The patient interface defined in claim 1 or claim 2, wherein the one flow director has a first opening to the first chamber and a second opening to the second chamber, the first and second openings enable gas to flow into the second chamber from the first chamber and which one flow director is configured to direct the gas flow through the one or more nare openings.
The patient interface defined in claim 3, wherein the first opening of the one flow director is off-set laterally from a mid-plane between lateral sides of the patient interface, having regard to an upright orientation of the patient interface.
The patient interface defined in claim 3 or claim 4, wherein the second opening of the one flow director is spaced laterally from a mid-plane between lateral sides of the patient interface, having regard to an upright orientation of the patient interface, and is spaced from the one or more nare openings.
The patient interface defined in any one of the preceding claims, wherein the one flow director has a base which joins with the dividing wall and which defines the first opening from the first chamber, a body extending from the base, a rim remote from the base and which rim defines the second opening which opens into the second chamber and a gas flow channel extending from the first opening in the base to the second opening.
The patient interface defined in claim 6, wherein the rim is contoured so that at least a portion of the rim has a substantially consistent spacing from the one or more nare openings.
The patient interface defined in claim 6 or claim 7, wherein the body includes a lower body portion and an upper body portion and the upper body portion includes a wall thickness that is less than a wall thickness of the lower body portion.
The patient interface defined in any one of claims 6 to 8, wherein the body has a conical profile, tapering profile or a stepped profile in cross-section generally orthogonal to the dividing wall where the one flow director is located.
The patient interface defined in any one of the preceding claims, wherein the dividing wall includes a preferential deformation region which decouples one portion of the dividing wall from another portion of the dividing wall such that the two portions can move relative to each other.
The patient interface defined in any one of the preceding claims, wherein the patient interface has an inlet to the first chamber for respiratory gas and an exhaust vent that is configured to communicate respiratory gas from the second chamber to externally of the patient interface.
The patient interface defined in any one of the preceding claims, wherein the patient interface further includes a patient-engagement surface and the dividing wall includes one or more deformation resistant sections configured to reduce the extent to which the one flow director deform due to deformation forces applied to the patient-engagement surface.
The patient interface defined in claim 12, wherein the one or more of the deformation resistant sections comprise portions of the dividing wall that have a wall thickness that is greater than the wall thickness of other portions of the dividing wall.
The patient interface defined in claim 12 or claim 13, wherein the one or more deformation resistant sections are in the region of the dividing wall that includes the one flow director.
The patient interface defined in any one of the preceding claims, wherein the outer wall is provided by a cushion module including a resilient seal member and a housing and wherein the seal member and the housing together form the first and second chambers.

Description

TECHNICAL FIELD The present invention relates to a patient interface for delivering respiratory gas to a patient. In particular, the present invention relates to a non-invasive patient interface. BACKGROUND One current treatment for respiratory diseases, such as thoracic restrictive diseases, acute respiratory failure, advanced neuromuscular diseases, chronic obstructive pulmonary disease (COPD - which includes emphysema, refractory asthma and chronic bronchitis), is non-invasive ventilation (NIV). There is some evidence to suggest that NIV therapy may be useful for assisting respiration after intubation, including reducing the chances of re-intubation. The NIV treatment applies a positive airway pressure to the lungs throughout the inhalation and exhalation cycle so as to splint the airways open. This improves the flow of respiratory gas into and out of the lungs. However, one side effect of the positive pressure applied in current NIV treatments is that the therapy pressures applied can make patients uncomfortable and, therefore, less willing to undergo the treatment. A follow-on effect of the positive pressure is that it requires the patient interface to be secured firmly to the patient to avoid leakages and, thereby ensure that the pressure is maintained in the patient interface and the respiratory system. Such firm application of the interface can cause pressure sores, particularly for patients that are semi-conscious or unconscious and, therefore, are unable to provide feedback on any soreness caused by the pressure of the patient interface on their skin. The NIV treatment gives rise to two challenges, namely compliance (the extent to which patients are willing to submit to the treatment) and pressure sores. In addition to these challenges, a further challenge for patients with obstructive respiration diseases is flushing carbon dioxide out of anatomical dead space. Specifically, the end of the exhalation cycle is characterised by a reduction in pressure of the exhaled respiratory gas. This means that the carbon dioxide-loaded respiratory gas remains in the throat, nose and mouth of the patient and is pulled back into the lungs at the commencement of the inhalation cycle. Replacing the carbon dioxide-loaded respiratory gas in these regions with respiratory gas that includes higher levels of oxygen than the carbon dioxide-loaded respiratory gas therefore assists patients in achieving sufficient respiration. It is desirable to provide a patient interface that improves patient comfort and that reduces pressure sores. It is also desirable to provide a patient interface that assists with flushing anatomical dead space. SUMMARY OF THE DISCLOSURE The present invention will now be described by way of a set of embodiments. However, it will be appreciated that the invention may be defined by combining the features of two or more of the embodiments. According to a first aspect, there is provided a non-invasive patient interface which is configured to seal about the mouth and nares of a patient, the patient interface including: (a) an outer wall defining an interior volume which includes a first chamber having one or more oral openings to communicate gas with the mouth and a second chamber having one or more nare openings to communicate gas with the nares; and(b) a dividing wall that separates the first chamber from the second chamber; and(c) one or more flow directors which enable gas to flow into the second chamber from the first chamber and which flow directors are configured to direct the gas flow through the one or more nare openings. The one or more flow directors may extend from the dividing wall. The one or more flow directors may be located in a central region of the dividing wall such that each flow director is spaced from a perimeter of the dividing wall. The one or more flow directors may extend from the dividing wall in to the first chamber or into the second chamber or into both the first and the second chambers. The one or more flow directors may extend toward the one or more nare openings. The dividing wall may be joined with the outer wall to separate the first chamber from the second chamber. The dividing wall may join with the outer wall at a location spaced from the one or more nare openings. The dividing wall may join with the outer wall across the entire width of the The dividing wall may join with the outer wall between the at least one or more nare openings and the at least one or more oral openings. The dividing wall may join with the outer wall closer to the one or more oral openings than the one or more nare openings. The outer wall may include a wall portion between the at least one or more nare openings and the at least one or more oral openings and the join between the dividing wall and the wall portion may be located in a lower half of the wall portion. The width of the wall portion may be defined between the laterally outermost ends of the one or more nare openings. The one or more