LIQUID CHAMBER FOR A BREATHING ASSISTANCE APPARATUS

TECHNICAL FIELD

[OOOl] The present invention relates to a liquid chamber for a breathing assistance apparatus.

BACKGROUND ART

[0002] Breathing assistance apparatuses are used in various environments such as hospital, medical facility, residential care, or home environments to deliver a flow of gas to users or patients. The breathing assistance apparatuses come in various forms, such as a standalone humidifier apparatus, a continuous positive airway pressure (CPAP) apparatus, or a high flow apparatus.

[0003] A standalone humidifier apparatus can deliver heated and humidified gases for various medical procedures, including respiratory therapy, laparoscopy, and the like. These apparatuses can be configured to control temperature and/or humidity. The apparatuses can also include medical circuits comprising various components that can be used to transport heated and/or humidified gases to and from patients. For example, in some breathing circuits, gases inhaled by a patient are delivered from a heater-humidifier through an inspiratory tube or conduit. As another example, tubes can deliver humidified gas (commonly CO2) into the abdominal cavity in insufflation circuits. This can help prevent desiccation or 'drying out' of the patient's internal organs, and can decrease the amount of time needed for recovery from surgery. Heater wires may extend inside of at least a portion of the tubing forming the circuit to prevent or at least reduce the likelihood of the formation of significant condensation.

[0004] A standalone humidifier apparatus would typically include a heater base and a humidifier liquid chamber. The heater base can comprise a heater plate. The liquid chamber can be configured to hold a volume of a liquid, such as water. The heater plate can be configured to heat the volume of liquid held within the liquid chamber to produce vapour.

[0005] The liquid chamber is removable from the heater base to allow the liquid chamber to be more readily sterilized or disposed, or to re-fill the chamber with liquid. The body of the liquid chamber can be formed from a non-conductive

glass or plastics material but the liquid chamber can also include conductive components. For instance, the liquid chamber can include a highly heat-conductive base (for example, an aluminum base) contacting or associated with the heater plate on the heater base.

[0006] The heater base can also include electronic controls such as a master controller. In response to user-set humidity or temperature values input via a user interface and other inputs, the master controller determines when (or to what level) to energize the heater plate to heat the liquid within the liquid chamber.

[0007] The standalone humidifier apparatus can include a gases supply to deliver gases to the liquid chamber. In some configurations, the gases supply can comprise a ventilator, blower, or any other suitable source of pressurized gases suitable for breathing or use in medical procedures.

[0008] A standalone humidifier apparatus can be used with breathing therapies, positive pressure apparatus, noninvasive ventilation, surgical procedures including but not limited to laparoscopy, and the like. Desirably, the humidifier apparatus can be adapted to supply humidity or vapour to a supply of gases. The humidifier apparatus can be used with continuous, variable, or bi-level PAP systems or other form of respiratory therapy. In some configurations, the humidifier apparatus can be integrated into a system that delivers any such types of therapy.

[0009] An exemplary standalone humidifier apparatus is described in WO 2015/038013.

[0010] A CPAP apparatus is a gases supply and optionally gases humidification apparatus. The apparatus is operable to provide respiratory assistance to patients or users who require a supply of gas (humidified or otherwise) at positive pressure for the treatment of diseases such as Obstructive Sleep Apnea (OSA), snoring, or Chronic Obstructive Pulmonary Disease (COPD) and the like. A CPAP apparatus would typically include a humidifier liquid chamber, so as to form a combined assisted breathing unit and humidifier.

[0011] CPAP apparatuses, when used with a humidifier, typically have a structure where gases at a required pressure are delivered from an assisted breathing unit or blower unit to a liquid chamber downstream from the blower. As the gases pass through the liquid chamber, they become saturated with liquid

vapour (e.g. water vapour). A flexible tubular gases conduit delivers the gases to a user or patient downstream from the humidifier chamber.

[0012] An exemplary CPAP apparatus is described in WO 2011/056080.

[0013] A high flow apparatus may be used to deliver a high gas flow or high flow therapy to a patient to assist with breathing and/or treat breathing disorders including chronic obstructive pulmonary disease (COPD). A high flow apparatus includes a gases supply and typically includes a humidification apparatus.

[0014] The breathing assistance apparatuses typically have one or more accessories such as a breathing conduit and a patient interface such as a cannula or mask for delivering gases to a patient. The conduit enables gases to be delivered from the housing of the breathing assistance apparatus to the patient. For example, the apparatus may be placed on a floor or other support surface, and the patient may be in a bed. The breathing assistance apparatus may have a recess for receipt of a humidifier liquid chamber. The liquid chamber will receive liquid from, for example, a flexible liquid bag that delivers liquid to a humidifier liquid chamber via one or more tubes. Alternatively, the liquid chamber can be removed and refilled as required. The recess will contain a heater plate to heat the liquid chamber, to humidify gases passing through the liquid chamber. The humidified gases are then delivered to the patient.

SUMMARY

[0015] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a humidifier liquid chamber or a humidifier liquid chamber manifold is disclosed, the humidifier liquid chamber or humidifier liquid chamber manifold comprising:

first and second base unit connection ports for connecting to a breathing assistance apparatus base unit, the base unit connection ports defining respective axes;

wherein the base unit connection ports are substantially parallel to each other and are separated by a port separation distance between the axes;

wherein at least one of the base unit connection ports has a sealing depth defined by a portion of the port that is configured to overlap with a complementary chamber connection port of the base unit, wherein a ratio of the sealing depth to port separation distance is more than about 0.25.

[0016] In some configurations, the ratio of the sealing depth to port separation distance is more than about 0.25 and up to about 0.7.

[0017] In some configurations, the ratio of the sealing depth to port separation distance is between about 0.3 and about 0.7.

[0018] In some configurations, the ratio of the sealing depth to port separation distance is about 0.475.

[0019] In some configurations, the sealing depth is more than about 10 mm.

[0020] In some configurations, the sealing depth is more than about 10 mm and up to about 16 mm.

[0021] In some configurations, the sealing depth is more than about 12 mm.

[0022] In some configurations, the sealing depth is more than about 12 mm and up to about 16 mm.

[0023] In some configurations, the at least one of the base unit connection ports is configured to seal with at least two seals on the complementary chamber connection port.

[0024] In some configurations, the base unit connection ports each have an exterior face, and wherein the exterior faces are substantially planar and are substantially perpendicular to the axes.

[0025] In some configurations, the humidifier liquid chamber manifold comprises first and second manifold-to-chamber connection ports for connecting to a humidifier liquid chamber, wherein the first manifold-to-chamber connection port is in fluid communication with the first base unit connection port, and wherein the second manifold-to-chamber connection port is in fluid communication with the second base unit connection port.

[0026] In some configurations of the humidifier liquid chamber manifold, a first conduit extends between and fluidly connects the first manifold-to-chamber connection port and the first base unit connection port, and a second conduit extends between and fluidly connects the second manifold-to-chamber connection port and the second base unit connection port.

[0027] In some configurations of the humidifier liquid chamber manifold, the axes of the first and second base unit connection ports are configured to be in a substantially horizontal orientation when the humidifier liquid chamber manifold is in use.

[0028] In some configurations of the humidifier liquid chamber manifold, axes of the first and second manifold-to-chamber connection ports are configured to be in a substantially vertical orientation when the humidifier liquid chamber manifold is in use.

[0029] In some configurations of the humidifier liquid chamber manifold, the humidifier liquid chamber manifold comprises an auxiliary port that is in communication with an interior of the humidifier liquid chamber manifold.

[0030] In some configurations of the humidifier liquid chamber manifold, the humidifier liquid chamber manifold comprises a conduit clip to engage with a liquid conduit for delivering liquid to a humidifier liquid chamber.

[0031] In some configurations, the humidifier liquid chamber manifold is integrally formed as part of a humidifier liquid chamber.

[0032] In some configurations, the port separation distance is between about 35 mm and about 45 mm.

[0033] In some configurations, the port separation distance is between about 38 mm and about 42 mm.

[0034] In some configurations, the port separation distance is about 40 mm +/- 0.6mm.

[0035] In some configurations, the humidifier liquid chamber comprises flow tubes extending into the humidifier liquid chamber from the first and second base unit connection ports.

[0036] In some configurations of the humidifier liquid chamber, each flow tube comprises an opening at or adjacent an end of the flow tube that is distal from the respective base unit connection port, wherein the opening is configured to direct flow and is spaced from a wall of the humidifier liquid chamber.

[0037] In some configurations of the humidifier liquid chamber, the opening in each flow tube faces a roof of the humidifier liquid chamber.

[0038] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises a baffle in the interior of the humidifier liquid chamber and between the openings of the flow tubes.

[0039] In some configurations of the humidifier liquid chamber, the baffle extends downward from a roof of the humidifier liquid chamber and terminates above a maximum liquid fill level of the humidifier liquid chamber.

[0040] In some configurations of the humidifier liquid chamber, a distance between a bottom edge of the baffle and the maximum liquid fill level is between about 5 mm and about 15 mm.

[0041] In some configurations of the humidifier liquid chamber, the baffle extends downward from a roof of the humidifier liquid chamber and terminates at or below a maximum liquid fill level of the humidifier liquid chamber.

[0042] In some configurations of the humidifier liquid chamber, a roof of the humidifier liquid chamber is sloped so as to be substantially non-horizontal in use.

[0043] In some configurations of the humidifier liquid chamber, at least one of the roof, the baffle, and wall(s) of the humidifier liquid chamber are configured to direct gases exiting the opening of the flow tube associated with the first base unit connection port toward and over a surface of liquid in the humidifier liquid chamber.

[0044] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises substantially no deadspace in the humidifier liquid chamber in use.

[0045] In some configurations of the humidifier liquid chamber, each flow tube comprises a liquid drainage aperture at or adjacent an end of the flow tube that is distal from the respective base unit connection port.

[0046] In some configurations of the humidifier liquid chamber, each flow tube comprises a gas bleed aperture in an upper surface of the flow tube.

[0047] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises a step in the humidifier liquid chamber.

[0048] In some configurations of the humidifier liquid chamber, a base of the step is located at least partly below the first and second base unit connection ports.

[0049] In some configurations of the humidifier liquid chamber, the baffle extends from a rear of the humidifier liquid chamber to a substantially vertical face of the step.

[0050] In some configurations of the humidifier liquid chamber, the baffle extends from a rear of the humidifier liquid chamber towards a substantially vertical face of the step, and terminates proximal to a central axis of the humidifier liquid chamber.

[0051] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber has a substantially cylindrical shape.

[0052] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber tapers towards a centre of the humidifier liquid chamber from a base of the humidifier liquid chamber to a top of the humidifier liquid chamber.

[0053] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises a heat conductive base.

[0054] In some configurations of the humidifier liquid chamber, the base of the humidifier liquid chamber is removable from a body of the humidifier liquid chamber.

[0055] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises one or more base removal features to assist with removing the base of the humidifier liquid chamber from the body of the humidifier liquid chamber.

[0056] In some configurations of the humidifier liquid chamber, the one or more base removal features is/are located between a lower flange of the body of

the humidifier liquid chamber and an outwardly extending flange of the base of the humidifier liquid chamber.

[0057] In some configurations of the humidifier liquid chamber, the one or more base removal features comprises a slot.

[0058] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises a shoulder between the first and second base unit connection ports.

[0059] In some configurations of the humidifier liquid chamber, the shoulder extends beyond exterior faces of the first and second base unit connection ports.

[0060] In some configurations of the humidifier liquid chamber, one of the base unit connection ports is an inlet port and the other of the base unit connection ports is an outlet port.

[0061] Additionally, in accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a humidifier liquid chamber or a humidifier liquid chamber manifold is disclosed, the humidifier liquid chamber or humidifier liquid chamber manifold comprising:

first and second base unit connection ports for connecting to a breathing assistance apparatus base unit;

wherein the base unit connection ports are substantially parallel to each other;

wherein each of the base unit connection ports comprises at least two sealing portions configured to form at least two seals with a portion of the breathing assistance apparatus base unit when connected to the breathing assistance apparatus base unit.

[0062] In some configurations, the two sealing portions are separated by a distance of about 5 mm to about 7 mm.

[0063] In some configurations, the two sealing portions are separated by a distance of about 5.5 mm to about 6.5 mm.

[0064] In some configurations, each base unit connection port comprises an internal taper such that the base unit port narrows from a terminal end of the base unit port towards an opposite end of the base unit port.

[0065] In some configurations, an inner diameter of a first one of the sealing portions proximal to the terminal end of the base unit port is about 0 mm to about 0.6 mm greater than an inner diameter of a second one of the sealing portions distal the terminal end of the base unit port.

[0066] In some configurations, the inner diameter of the first one of the sealing portions is less than about 25.6 mm.

[0067] In some configurations, the inner diameter of the second one of the sealing portions is less than about 25.4 mm.

[0068] In some configurations of the humidifier liquid chamber, each base unit connection port comprises a central axis that is at least about 85 mm above a lower surface of a body of the humidifier liquid chamber.

[0069] In some configurations of the humidifier liquid chamber, the central axes of the base unit connection ports are at least about 88 mm above the lower surface of the body of the humidifier liquid chamber.

[0070] In some configurations of the humidifier liquid chamber, the lower surface is defined by an upper edge of a lower flange of the body of the humidifier liquid chamber.

[0071] In some configurations of the humidifier liquid chamber, the lower flange is configured to engage with one or more retaining features in a breathing assistance apparatus base unit to assist with retaining the humidifier liquid chamber in engagement with the breathing assistance apparatus base unit.

[0072] In some configurations of the humidifier liquid chamber or humidifier liquid chamber manifold, each base unit connection port is cylindrical.

[0073] In some configurations of the humidifier liquid chamber or humidifier liquid chamber manifold, each base unit connection port is configured to receive a complementary port of a breathing assistance apparatus base unit.

[0074] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises flow tubes extending into the humidifier liquid chamber from the first and second base unit connection ports.

[0075] In some configurations of the humidifier liquid chamber, the liquid chamber comprises a baffle in the interior of the humidifier liquid chamber and between openings of the flow tubes.

[0076] In some configurations of the humidifier liquid chamber, the baffle extends downward from a roof of the humidifier liquid chamber and terminates above a maximum liquid fill level of the humidifier liquid chamber.

[0077] In some configurations of the humidifier liquid chamber, the baffle extends downward from a roof of the humidifier liquid chamber and terminates at or below a maximum liquid fill level of the humidifier liquid chamber.

[0078] In some configurations of the humidifier liquid chamber, a roof of the humidifier liquid chamber is sloped so as to be substantially non-horizontal in use.

[0079] In some configurations of the humidifier liquid chamber, at least one of the roof, the baffle, and wall(s) of the humidifier liquid chamber are configured to direct gases exiting the opening of the flow tube associated with the first base unit connection port toward and over a surface of liquid in the humidifier liquid chamber.

[0080] In some configurations of the humidifier liquid chamber, the liquid chamber comprises a step in the humidifier liquid chamber.

[0081] In some configurations of the humidifier liquid chamber, a base of the step is located at least partly below the first and second base unit connection ports.

[0082] In some configurations of the humidifier liquid chamber, the baffle extends from a rear of the humidifier liquid chamber towards a substantially vertical face of the step, and terminates proximal to a central axis of the humidifier liquid chamber.

[0083] In some configurations of the humidifier liquid chamber, a distance between a forward edge of the baffle and the substantially vertical face of the step is at least about 20 mm.

[0084] In some configurations of the humidifier liquid chamber or humidifier liquid chamber manifold, the first and second base unit connection ports define respective axes, and the first and second base unit connection ports are separated by a port separation distance between the axes, and wherein the port separation distance is between about 35 mm and about 45 mm.

[0085] In some configurations of the humidifier liquid chamber or humidifier liquid chamber manifold, the port separation distance is between about 38 mm and about 42 mm.

[0086] In some configurations of the humidifier liquid chamber or humidifier liquid chamber manifold, the port separation distance is about 40 mm +/- 0.6mm

[0087] Additionally, in accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a humidifier liquid chamber is disclosed, the humidifier liquid chamber comprising:

an inlet port and an outlet port, the inlet port and the outlet port defining respective axes;

wherein the inlet port and the outlet port are substantially parallel to each other and are configured to be in a substantially horizontal orientation when the humidifier liquid chamber is in use, and wherein the inlet port and the outlet port are separated by a port separation distance between the axes;

wherein at least one of the inlet port and the outlet port has a sealing depth defined by a portion of the port that is configured to overlap with a complementary chamber connection port of a breathing assistance apparatus base unit, wherein a ratio of the sealing depth to port separation distance is more than about 0.25 and up to about 0.7.

[0088] In some configurations, the ratio of the sealing depth to port separation distance is between about 0.3 and about 0.7.

[0089] In some configurations, the ratio of the sealing depth to port separation distance is about 0.475.

[0090] In some configurations, the sealing depth is more than about 10 mm.

[0091] In some configurations, the sealing depth is more than about 10 mm and up to about 16 mm.

[0092] In some configurations, the sealing depth is more than about 12 mm.

[0093] In some configurations, the sealing depth is more than about 12 mm and up to about 16 mm.

[0094] In some configurations, the at least one of the inlet port and the outlet port is configured to seal with at least two seals on the complementary chamber connection port.

[0095] In some configurations, the port separation distance is between about 35 mm and about 45 mm.

[0096] In some configurations, the port separation distance is between about 38 mm and about 42 mm.

[0097] In some configurations, the port separation distance is about 40 mm +/- 0.6mm.

[0098] In some configurations, the humidifier liquid chamber comprises flow tubes extending into the humidifier liquid chamber from the inlet port and the outlet port.

[0099] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises each flow tube comprises an opening at or adjacent an end of the flow tube that is distal from the respective port, wherein the opening is configured to direct flow and is spaced from a wall of the humidifier liquid chamber.

[00100] In some configurations, the opening in each flow tube faces a roof of the humidifier liquid chamber.

[00101] In some configurations, the humidifier liquid chamber comprises a baffle in the interior of the humidifier liquid chamber and between the openings of the flow tubes.

[00102] In some configurations, the baffle extends downward from a roof of the humidifier liquid chamber and terminates above a maximum liquid fill level of the humidifier liquid chamber.

[00103] In some configurations, a distance between a bottom edge of the baffle and the maximum liquid fill level is between about 5 mm and about 15 mm.

[00104] In some configurations, the baffle extends downward from a roof of the humidifier liquid chamber and terminates at or below an intended maximum liquid fill level of the humidifier liquid chamber.

[00105] In some configurations, a roof of the humidifier liquid chamber is sloped so as to be substantially non-horizontal in use.

[00106] In some configurations, at least one of the roof, the baffle, and wall(s) of the humidifier liquid chamber are configured to direct gases exiting the opening of the flow tube associated with the inlet port toward and over a surface of liquid in the humidifier liquid chamber.

[00107] In some configurations, the humidifier liquid chamber comprises substantially no deadspace in the humidifier liquid chamber in use.

[00108] In some configurations, each flow tube comprises a liquid drainage aperture at or adjacent an end of the flow tube that is distal from the respective port of the humidifier liquid chamber.

[00109] In some configurations, each flow tube comprises an air bleed aperture in an upper surface of the flow tube.

[00110] In some configurations, the humidifier liquid chamber comprises a step in the humidifier liquid chamber.

[00111] In some configurations, a base of the step is located at least partly below the inlet port and the outlet port.

[00112] In some configurations, the baffle extends from a rear of the humidifier liquid chamber to a substantially vertical face of the step.

[00113] In some configurations, the baffle extends from a rear of the humidifier liquid chamber towards a substantially vertical face of the step, and terminates proximal to a central axis of the humidifier liquid chamber.

[00114] In some configurations, the humidifier liquid chamber has a substantially cylindrical shape.

[00115] In some configurations, the humidifier liquid chamber tapers towards a centre of the humidifier liquid chamber from a base of the humidifier liquid chamber to a top of the humidifier liquid chamber.

[00116] In some configurations, the humidifier liquid chamber comprises a heat conductive base.

[00117] In some configurations of the humidifier liquid chamber, the base of the humidifier liquid chamber is removable from a body of the humidifier liquid chamber.

[00118] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises one or more base removal features to assist with removing the base of the humidifier liquid chamber from the body of the humidifier liquid chamber.

[00119] In some configurations of the humidifier liquid chamber, the one or more base removal features is/are located between a lower flange of the body of the humidifier liquid chamber and an outwardly extending flange of the base of the humidifier liquid chamber.

[00120] In some configurations of the humidifier liquid chamber, the one or more base removal features comprises a slot.

[00121] In some configurations, the humidifier liquid chamber comprises a shoulder between the inlet port and the outlet port.

[00122] In some configurations, the shoulder extends beyond exterior faces of the inlet port and the outlet port.

[00123] Additionally, in accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a humidifier liquid chamber manifold is disclosed, the humidifier liquid chamber manifold comprising:

a base unit connection portion comprising:

first and second base unit connection ports for connecting to a breathing assistance apparatus base unit, the base unit connection ports defining respective axes;

wherein the base unit connection ports are substantially parallel to each other and are separated by a port separation distance between the axes;

wherein at least one of the base unit connection ports has a sealing depth defined by a portion of the port that is configured to overlap with a complementary connection port of the base unit, wherein the ratio of the sealing depth to the port separation distance is more than about 0.25; and a humidifier liquid chamber connection portion comprising:

first and second manifold-to-chamber connection ports for connecting to a humidifier liquid chamber, wherein the first manifold-to-chamber connection port is in fluid communication with the first base unit connection port, and wherein the second manifold-to-chamber connection port is in fluid communication with the second base unit connection port.

[00124] In some configurations, the ratio of the sealing depth to the port separation distance is more than about 0.25 and up to about 0.7.

[00125] In some configurations, the ratio of the sealing depth to the port separation distance is between about 0.3 and about 0.7.

[00126] In some configurations, the ratio of the sealing depth to the port separation distance is about 0.475.

[00127] In some configurations, the sealing depth is more than about 10 mm.

[00128] In some configurations, the sealing depth is more than about 10 mm and up to about 16mm.

[00129] In some configurations, the sealing depth is more than about 12 mm.

[00130] In some configurations, the sealing depth is more than about 12 mm and up to about 16 mm.

[00131] In some configurations, the at least one of the base unit connection ports is configured to seal with at least two seals on the complementary connection port of the base unit.

[00132] In some configurations, the port separation distance is between about 35 mm and about 45 mm.

[00133] In some configurations, the port separation distance is between about 38 mm and about 42 mm.

[00134] In some configurations, a first conduit extends between and fluidly connects the first manifold-to-chamber connection port and the first base unit connection port, and wherein a second conduit extends between and fluidly connects the second manifold-to-chamber connection port and the second base unit connection port.

[00135] In some configurations, the axes of the first and second base unit connection ports are configured to be in a substantially horizontal orientation when the humidifier liquid chamber manifold is in use.

[00136] In some configurations, axes of the first and second manifold-to-chamber connection ports are configured to be in a substantially vertical orientation when the humidifier liquid chamber manifold is in use.

[00137] In some configurations, the humidifier liquid chamber manifold comprises an auxiliary port that is in communication with an interior of the humidifier liquid chamber manifold.

[00138] In some configurations, the humidifier liquid chamber manifold comprises a conduit clip to engage with a liquid conduit for delivering liquid to a humidifier liquid chamber.

[00139] Additionally, in accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a humidifier liquid chamber is disclosed, the humidifier liquid chamber comprising:

a base, a top, and one or more side walls;

an inlet port and an outlet port, the inlet port and the outlet port defining axes;

at least two grips in the side wall(s), wherein the grips are located at an angle relative to a plane that extends through a centre of the humidifier liquid chamber transversely to the axes of the inlet port and the outlet port.

[00140] In some configurations, the angle is between about 0 degrees and about 40 degrees relative to the plane.

[00141] In some configurations, the angle is between about 10 degrees and about 40 degrees relative to the plane.

[00142] In some configurations, each grip is at a grip distance from the centre of the humidifier liquid chamber, wherein the distance is between about 50 mm and about 70 mm.

[00143] In some configurations, the grip distance is between about 55 mm and about 65 mm.

[00144] In some configurations, the grips are located on opposing sides of the humidifier liquid chamber.

[00145] In some configurations, the grips extend downwardly from the top of the humidifier liquid chamber.

[00146] In some configurations, the grips extend part way down from the top of the humidifier liquid chamber.

[00147] In some configurations, the grips comprise inward recesses.

[00148] In some configurations, the recesses are scalloped.

[00149] In some configurations, the recesses have a radius of between about

10 mm and about 20 mm.

[00150] In some configurations, the grips have substantially smooth grip surfaces.

[00151] In some configurations, the grips have textured grip surfaces.

[00152] In some configurations, the chamber has a substantially cylindrical shape.

[00153] In some configurations, the chamber tapers towards a centre of the humidifier liquid chamber from a base of the humidifier liquid chamber to a top of the humidifier liquid chamber.

[00154] In some configurations, the base is heat conductive.

[00155] In some configurations of the humidifier liquid chamber, the base of the humidifier liquid chamber is removable from a body of the humidifier liquid chamber.

[00156] In some configurations of the humidifier liquid chamber, the humidifier liquid chamber comprises one or more base removal features to assist with removing the base of the humidifier liquid chamber from the body of the humidifier liquid chamber.

[00157] In some configurations of the humidifier liquid chamber, the one or more base removal features is/are located between a lower flange of the body of the humidifier liquid chamber and an outwardly extending flange of the base of the humidifier liquid chamber.

[00158] In some configurations of the humidifier liquid chamber, the one or more base removal features comprises a slot.

[00159] In some configurations, the inlet port and outlet port are located at a front of the humidifier liquid chamber.

[00160] In some configurations, the grips are located in sides of the humidifier liquid chamber, rearward of the plane.

[00161] In some configurations, the humidifier liquid chamber is configured to engage with a liquid chamber bay of a humidifier by sliding the humidifier liquid chamber substantially linearly into the liquid chamber bay.

[00162] Additionally, in accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a humidifier liquid chamber is disclosed, the humidifier liquid chamber comprising:

an inlet port and an outlet port, the inlet port and the outlet port defining respective axes, wherein the inlet port and the outlet port are substantially parallel to each other and are configured to be in a substantially horizontal orientation when the humidifier liquid chamber is in use;

flow tubes extending into the humidifier liquid chamber from the inlet port and the outlet port, wherein each flow tube comprises an opening at or adjacent an end of the flow tube that is distal from the respective port, wherein the opening is configured to direct flow and is spaced from a wall of the humidifier liquid chamber, and wherein the opening in each flow tube faces a roof of the humidifier liquid chamber; and

a baffle in the interior of the humidifier liquid chamber and between the openings of the flow tubes, wherein the baffle extends downward from a roof of the humidifier liquid chamber and terminates above a maximum liquid fill level of the humidifier liquid chamber.

[00163] In some configurations, a distance between a bottom edge of the baffle and the maximum liquid fill level is between about 5 mm and about 15 mm.

[00164] Additionally, in accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a breathing assistance apparatus is disclosed, the breathing assistance apparatus comprising a base unit and either:

the humidifier liquid chamber as outlined above; or

the humidifier liquid chamber manifold as outlined above coupled to or integrated with a humidifier liquid chamber.

[00165] In some configurations, the humidifier liquid chamber is located in a recess of the base unit.

[00166] In some configurations, the humidifier liquid chamber is removable from the recess of the base unit.

[00167] In some configurations, the ports of the humidifier liquid chamber or the base unit connection ports of the humidifier liquid chamber manifold are engaged with complementary chamber connection ports of the base unit.

[00168] In some configurations, the complementary chamber connection ports are arranged to be received in the ports of the humidifier liquid chamber or the base unit connection ports of the humidifier liquid chamber manifold.

[00169] In some configurations, an overlapping length of the ports of the humidifier liquid chamber or the base unit connection ports of the humidifier liquid chamber manifold and the complementary chamber connection ports is sufficient to provide protection against liquid ingress.

[00170] In some configurations, the base unit comprises a plurality of seals on each of complementary chamber connection ports.

[00171] In some configurations, the base unit comprises a flow generator.

[00172] In some configurations, the base unit is configured to fluidly connect to a separate or remote flow generator.

[00173] Features from one or more embodiments or configurations may be combined with features of one or more other embodiments or configurations.

Additionally, more than one embodiment may be used together during a process of respiratory support of a patient.

[00174] It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all ranges expressly disclosed herein are hereby expressly disclosed. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner.

[00175] It should be understood that alternative embodiments or configurations may comprise any or all combinations of two or more of the parts, elements or features illustrated, described or referred to in this specification.

[00176] This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features.

[00177] To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting. Where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

[00178] The term 'comprising' as used in this specification means 'consisting at least in part of'. When interpreting each statement in this specification that includes the term 'comprising', features other than that or those prefaced by the term may also be present. Related terms such as 'comprise' and ’comprises' are to be interpreted in the same manner.

[00179] As used herein the term '(s)' following a noun means the plural and/or singular form of that noun.

[00180] As used herein the term 'and/or' means 'and' or 'or', or where the context allows both.

[00181] The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

BRIEF DESCRIPTION OF THE DRAWINGS

[00182] Specific embodiments and modifications thereof will become apparent to those skilled in the art from the detailed description herein having reference to the figures that follow, of which:

[00183] Figure 1 shows in diagrammatic form a breathing assistance apparatus.

[00184] Figure 2 is a front/right side overhead perspective view of a breathing assistance apparatus with a humidifier liquid chamber positioned in the recess of the breathing assistance apparatus base unit.

[00185] Figure 3 is a front/left side overhead perspective view of the breathing assistance apparatus with the humidifier liquid chamber removed from the recess of the breathing assistance apparatus base unit.

[00186] Figure 4 is a front/right side overhead perspective view of the breathing assistance apparatus base unit with the humidifier liquid chamber and heater plate not shown.

[00187] Figure 5 is a front/right side bottom perspective view of the breathing assistance apparatus base unit with the humidifier liquid chamber not shown.

[00188] Figure 6 is a front/right side overhead perspective view of a removable elbow and shroud of the breathing assistance apparatus base unit.

[00189] Figure 7 is a right side view of the elbow.

[00190] Figure 8 is a rear/right side perspective view showing the elbow from below, and with the seal not shown.

[00191] Figure 9 is a top plan view of the shroud and elbow, prior to insertion of the elbow into the shroud.

[00192] Figure 10 is an enlarged right side view showing engagement features on the elbow engaging with the shroud (broken lines).

[00193] Figure 11 is a right side view of the elbow showing seals and the location of temperature sensor(s) in broken lines.

[00194] Figure 12 is a right side view of part of the elbow showing details of the seals.

[00195] Figure 13 is an overhead perspective view of the humidifier liquid chamber.

[00196] Figure 14 is an overhead plan view of the humidifier liquid chamber.

[00197] Figure 15 is a front view of the humidifier liquid chamber.

[00198] Figure 16 is a left side sectional view of the humidifier liquid chamber along line 16-16 of Figure 15.

[00199] Figure 17 is an overhead perspective view of one of the flow tubes of the humidifier liquid chamber.

[00200] Figure 18 is a front view of the humidifier liquid chamber showing an internal baffle in broken lines.

[00201] Figure 19 is a left side sectional view of the humidifier liquid chamber along the line 19-19 of Figure 18.

[00202] Figure 20 is a front/left side overhead perspective view of the breathing assistance apparatus base unit and humidifier liquid chamber, prior to insertion of the humidifier liquid chamber into the recess of the breathing assistance apparatus base unit.

[00203] Figure 21 is a front/left side overhead perspective view similar to Figure 20, but with the humidifier liquid chamber inserted into the recess of the breathing assistance apparatus base unit.

[00204] Figure 22 is a right side sectional view showing the interaction of the seals on one of the apparatus ports with one of the humidifier liquid chamber ports.

[00205] Figure 23 is a flow diagram from a computational fluid dynamics model showing the effect of humidifier liquid chamber baffle height on flow stagnation around the humidifier liquid chamber inlet for a humidifier liquid chamber with no gap between the baffle and the liquid in the chamber (left side), and for a humidifier liquid chamber with a 10 mm gap between the baffle and the liquid in the chamber (right side).

[00206] Figure 24 is a right side view of the humidifier liquid chamber showing a moment M created by an offset grip relative to the liquid chamber central axis.

[00207] Figure 25 is an overhead plan view of the humidifier liquid chamber showing dimensions for a thumb abducted large diameter grasp.

[00208] Figure 26 is an overhead perspective view of a humidifier liquid chamber and manifold assembly for use with the breathing assistance apparatus.

[00209] Figure 27 is an overhead plan view of the manifold.

[00210] Figure 28 is an overhead perspective view of the humidifier liquid chamber.

[00211] Figure 29 is a side part sectional view through one of the chamber connection ports of the manifold, showing its connection to one of the ports of the humidifier liquid chamber.

[00212] Figure 30 is an overhead perspective view of an alternative configuration humidifier liquid chamber with a removable base.

[00213] Figure 31 is an inverted side view of the alternative configuration humidifier liquid chamber with the base removed.

[00214] Figure 32 is a left side sectional view similar to Figure 19, showing an alternative baffle configuration of the humidifier liquid chamber.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[00215] A breathing assistance apparatus 10 for delivering a flow of gas (which may contain one or more gases) to a patient is shown in Figure 1. The apparatus 10 could, for example, be a CPAP apparatus or a high flow apparatus. An exemplary CPAP apparatus is described in WO 2011/056080. The contents of that specification are incorporated herein in their entirety by way of reference.

[00216] A CPAP apparatus is a gases supply and optionally gases humidification apparatus. The apparatus is operable to provide respiratory assistance to patients or users who require a supply of gas (humidified or otherwise) at positive pressure for the treatment of diseases such as Obstructive Sleep Apnea (OSA), snoring, or Chronic Obstructive Pulmonary Disease (COPD) and the like. A CPAP apparatus would typically include a humidifier liquid chamber, so as to form a combined assisted breathing unit and humidifier.

[00217] CPAP apparatuses, when used with a humidifier, typically have a structure where gases at a required pressure are delivered from an assisted breathing unit or blower unit to a humidifier liquid chamber downstream from the blower. As the gases pass through the humidifier liquid chamber, they become saturated with liquid vapour (e.g. water vapour). A flexible tubular gases conduit delivers the gases to a user or patient downstream from the humidifier liquid chamber.

[00218] A high flow apparatus may be used to deliver a high gas flow or high flow therapy to a patient to assist with breathing and/or treat breathing disorders including chronic obstructive pulmonary disease (COPD). A high flow apparatus includes a gases supply and typically includes a humidification apparatus.

[00219] The breathing assistance apparatuses typically have one or more accessories such as a breathing conduit and a patient interface such as a cannula or mask for delivering gases to a patient. The conduit enables gases to be delivered from the housing of the breathing assistance apparatus to the patient. For example, the apparatus may be placed on a floor or other support surface, and the patient may be in a bed. The breathing assistance apparatus may have a recess for receipt of a humidifier liquid chamber. The humidifier liquid chamber will receive liquid from, for example, a flexible liquid bag that delivers liquid to a humidifier liquid chamber via one or more tubes. Alternatively, the humidifier liquid chamber can be removed and refilled as required. The recess will contain a heater plate to heat the humidifier liquid chamber, to humidify gases passing through the humidifier liquid chamber. The humidified gases are then delivered to the patient.

[00220] In general terms, the apparatus 10 comprises a main housing 100 that contains a flow generator 11 in the form of a motor/impeller arrangement, a humidifier 12, a controller 13, and a user I/O interface 14 (comprising, for example, a display and input device(s) such as button(s), a touch screen, or the like). The controller 13 is configured or programmed to control the components of the apparatus, including: operating the flow generator 11 to create a flow of gas (gas flow) for delivery to a patient, operating the humidifier 12 to humidify and/or heat the generated gas flow, receive user input from the user interface 14 for reconfiguration and/or user-defined operation of the apparatus 10, and output information (for example on the display) to the user. The user could be a patient, healthcare professional, or anyone else interested in using the apparatus.

[00221] A patient breathing conduit 16 is connected to a gas flow output or patient outlet port 30 in the housing 100 of the breathing assistance apparatus 10, and is connected to a patient interface 17 such as a nasal cannula with a manifold 19 and nasal prongs 18. Additionally, or alternatively, the patient breathing conduit 16 could be connected to a face mask. Additionally, or alternatively, the patient breathing conduit could be connected to a nasal pillows mask, and/or a nasal mask, and/or a tracheostomy interface, or any other suitable type of patient interface. The gas flow, which may be humidified, that is generated by the breathing assistance apparatus 10 is delivered to the patient via the patient breathing conduit 16 through the patient interface 17. The patient breathing conduit 16 can have a heater wire 16a to heat gas flow passing through to the patient. The heater wire 16a is under the control of the controller 13. The patient breathing conduit 16 and/or patient interface 17 can be considered part of the breathing assistance apparatus 10, or alternatively peripheral to it. The breathing assistance apparatus 10, breathing conduit 16, and patient interface 17 may together form a breathing assistance system or, in some configurations, a flow therapy system.

[00222] General operation of an exemplary breathing assistance apparatus 10 will be known to those skilled in the art, and need not be described in detail here. However, in general terms, the controller 13 controls the flow generator 11 to generate a gas flow of the desired flow rate, controls one or more valves to control the mix of air and oxygen or other alternative gas, and/or controls the humidifier 12 to humidify the gas flow and/or heat the gas flow to an appropriate level. The gas flow is directed out through the patient breathing conduit 16 and patient interface 17 to the patient. The controller 13 can also control a heating element in the humidifier 12 and/or the heating element 16a in the patient breathing conduit 16 to humidify and/or heat the gas to a desired temperature that achieves a desired level of therapy and/or comfort for the patient. The controller 13 can be programmed with, or can determine, a suitable target temperature of the gas flow.

[00223] Operation sensors 3a, 3b, 3c, 20, and 25, such as flow, temperature, humidity, and/or pressure sensors, can be placed in various locations in the breathing assistance apparatus 10 and/or the patient breathing conduit 16 and/or patient interface 17. Output from the sensors can be received by the controller 13, to assist it to operate the breathing assistance apparatus 10 in a manner that provides optimal therapy. In some configurations, providing optimal therapy includes meeting a patient's inspiratory flow. The apparatus 10 may have a transmitter and/or receiver 15 to enable the controller 13 to receive signals 8 from the sensors and/or to control the various components of the breathing assistance apparatus 10, including but not limited to the flow generator 11, humidifier 12, and heater wire 16a, or accessories or peripherals associated with the breathing assistance apparatus 10. Additionally, or alternatively, the transmitter and/or receiver 15 may deliver data to a remote server or enable remote control of the apparatus 10.

[00224] The breathing assistance apparatus 10 may be any suitable type of apparatus, but in some configurations may deliver a high gas flow or high flow therapy (of e.g. air, oxygen, other gas mixture, or some combination thereof) to a patient to assist with breathing and/or treat breathing disorders. In some configurations, the gas is or comprises oxygen. In some configurations, the gas comprises a blend of oxygen and ambient air. High flow therapy as discussed herein is intended to be given its typical ordinary meaning as understood by a person of skill in the art which generally refers to a respiratory assistance system delivering a targeted flow of humidified respiratory gases via an intentionally unsealed patient interface with flow rates generally intended to meet or exceed inspiratory flow of a patient. Typical patient interfaces include, but are not limited to, a nasal or tracheal patient interface. Typical flow rates for adults often range from, but are not limited to, about fifteen liters per minute (LPM) to about seventy liters per minute or greater. Typical flow rates for pediatric patients (such as neonates, infants and children) often range from, but are not limited to, about one liter per minute per kilogram of patient weight to about three liters per minute per kilogram of patient weight or greater. High flow therapy can also optionally include gas mixture compositions including supplemental oxygen and/or administration of therapeutic medicaments. High flow therapy is often referred to as nasal high flow (NHF), humidified high flow nasal cannula (HHFNC), high flow nasal oxygen (HFNO), high flow therapy (HFT), or tracheal high flow (THF), among other common names.

[00225] For example, in some configurations, for an adult patient 'high flow therapy' may refer to the delivery of gases to a patient at a flow rate of greater than or equal to about 10 liters per minute (10 LPM), such as between about 10 LPM and about 100 LPM, or between about 15 LPM and about 95 LPM, or between about 20 LPM and about 90 LPM, or between about 25 LPM and about 85 LPM, or between about 30 LPM and about 80 LPM, or between about 35 LPM and about 75 LPM, or between about 40 LPM and about 70 LPM, or between about 45 LPM and about 65 LPM, or between about 50 LPM and about 60 LPM. In some configurations, for a neonatal, infant, or child patient 'high flow therapy' may refer to the delivery of gases to a patient at a flow rate of greater than 1 LPM, such as between about 1 LPM and about 25 LPM, or between about 2 LPM and about 25 LPM, or between about 2 LPM and about 5 LPM, or between about 5 LPM and about 25 LPM, or between about 5 LPM and about 10 LPM, or between about 10 LPM and about 25

LPM, or between about 10 LPM and about 20 LPM, or between about 10 LPM and 15 LPM, or between about 20 LPM and 25 LPM. A high flow therapy apparatus with an adult patient, a neonatal, infant, or child patient, may, in some configurations, deliver gases to the patient at a flow rate of between about 1 LPM and about 100 LPM, or at a flow rate in any of the sub-ranges outlined above. Gases delivered may comprise a percentage of oxygen. In some configurations, the percentage of oxygen in the gases delivered may be between about 20% and about 100%, or between about 30% and about 100%, or between about 40% and about 100%, or between about 50% and about 100%, or between about 60% and about 100%, or between about 70% and about 100%, or between about 80% and about 100%, or between about 90% and about 100%, or about 100%, or 100%.

[00226] High flow therapy has been found effective in meeting or exceeding the patient's inspiratory flow, increasing oxygenation of the patient and/or reducing the work of breathing. Additionally, high flow therapy may generate a flushing effect in the nasopharynx such that the anatomical dead space of the upper airways is flushed by the high incoming gas flows. This creates a reservoir of fresh gas available for each and every breath, while minimising re-breathing of carbon dioxide, nitrogen, etc.

CLAIMS

1. A humidifier liquid chamber or a humidifier liquid chamber manifold comprising:

first and second base unit connection ports for connecting to a breathing assistance apparatus base unit, the base unit connection ports defining respective axes;

wherein the base unit connection ports are substantially parallel to each other and are separated by a port separation distance between the axes;

wherein at least one of the base unit connection ports has a sealing depth defined by a portion of the port that is configured to overlap with a complementary chamber connection port of the base unit, wherein a ratio of the sealing depth to port separation distance is more than about 0.25.

2. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 1, wherein the ratio of the sealing depth to port separation distance is more than about 0.25 and up to about 0.7.

3. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 2, wherein the ratio of the sealing depth to port separation distance is between about 0.3 and about 0.7.

4. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 3, wherein the ratio of the sealing depth to port separation distance is about 0.475.

5. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 1 to 4, wherein the sealing depth is more than about 10 mm.

6. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 5, wherein the sealing depth is more than about 10 mm and up to about 16 mm.

7. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 5, wherein the sealing depth is more than about 12 mm.

8. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 7, wherein the sealing depth is more than about 12 mm and up to about 16 mm.

9. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 1 to 8, wherein said at least one of the base unit connection ports is configured to seal with at least two seals on the complementary chamber connection port.

10. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 1 to 9, wherein the base unit connection ports each have an exterior face, and wherein the exterior faces are substantially planar and are substantially perpendicular to the axes.

11. The humidifier liquid chamber manifold according to any one of claims 1 to 10, comprising first and second manifold-to-chamber connection ports for connecting to a humidifier liquid chamber, wherein the first manifold-to-chamber connection port is in fluid communication with the first base unit connection port, and wherein the second manifold-to-chamber connection port is in fluid communication with the second base unit connection port.

12. The humidifier liquid chamber manifold according to claim 11, wherein a first conduit extends between and fluidly connects the first manifold-to-chamber connection port and the first base unit connection port, and wherein a second conduit extends between and fluidly connects the second manifold-to-chamber connection port and the second base unit connection port.

13. The humidifier liquid chamber manifold according to claim 11 or 12, wherein the axes of the first and second base unit connection ports are configured to be in a substantially horizontal orientation when the humidifier liquid chamber manifold is in use.

14. The humidifier liquid chamber manifold according to claim 13, wherein axes of the first and second manifold-to-chamber connection ports are configured to be in a substantially vertical orientation when the humidifier liquid chamber manifold is in use.

15. The humidifier liquid chamber manifold according to any one of claims 10 to

14, comprising an auxiliary port that is in communication with an interior of the humidifier liquid chamber manifold.

16. The humidifier liquid chamber manifold according to any one of claims 10 to

15, comprising a conduit clip to engage with a liquid conduit for delivering liquid to a humidifier liquid chamber.

17. The humidifier liquid chamber manifold according to any one of claims 10 to

16, that is integrally formed as part of a humidifier liquid chamber.

18. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 1 to 17, wherein the port separation distance is between about 35 mm and about 45 mm.

19. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 18, wherein the port separation distance is between about 38 mm and about 42 mm.

20. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 19, wherein the port separation distance is about 40 mm +/-0.6mm.

21. The humidifier liquid chamber according to any one of claims 1 to 10 or 18 to 20, comprising flow tubes extending into the humidifier liquid chamber from the first and second base unit connection ports.

22. The humidifier liquid chamber according to claim 21, wherein each flow tube comprises an opening at or adjacent an end of the flow tube that is distal from the respective base unit connection port, wherein the opening is configured to direct flow and is spaced from a wall of the humidifier liquid chamber.

23. The humidifier liquid chamber according to claim 22, wherein the opening in each flow tube faces a roof of the humidifier liquid chamber.

24. The humidifier liquid chamber according to claim 22 or 23, comprising a baffle in the interior of the humidifier liquid chamber and between the openings of the flow tubes.

25. The humidifier liquid chamber according to claim 24, wherein the baffle extends downward from a roof of the humidifier liquid chamber and terminates above a maximum liquid fill level of the humidifier liquid chamber.

26. The humidifier liquid chamber according to claim 25, wherein a distance between a bottom edge of the baffle and the maximum liquid fill level is between about 5 mm and about 15 mm.

27. The humidifier liquid chamber according to claim 24, wherein the baffle extends downward from a roof of the humidifier liquid chamber and terminates at or below a maximum liquid fill level of the humidifier liquid chamber.

28. The humidifier liquid chamber according to any one of claims 24 to 27, wherein a roof of the humidifier liquid chamber is sloped so as to be substantially non-horizontal in use.

29. The humidifier liquid chamber according to claim 28, wherein at least one of the roof, the baffle, and wall(s) of the humidifier liquid chamber are configured to direct gases exiting the opening of the flow tube associated with the first base unit connection port toward and over a surface of liquid in the humidifier liquid chamber.

30. The humidifier liquid chamber according to claim 29 when dependent on claim 25 or 26, comprising substantially no deadspace in the humidifier liquid chamber in use.

31. The humidifier liquid chamber according to any one of claims 21 to 30, wherein each flow tube comprises a liquid drainage aperture at or adjacent an end of the flow tube that is distal from the respective base unit connection port.

32. The humidifier liquid chamber according to any one of claims 21 to 31, wherein each flow tube comprises a gas bleed aperture in an upper surface of the flow tube.

33. The humidifier liquid chamber according to any one of claims 1 to 10 or 18 to 32, comprising a step in the humidifier liquid chamber.

34. The humidifier liquid chamber according to claim 33, wherein a base of the step is located at least partly below the first and second base unit connection ports.

35. The humidifier liquid chamber according to claim 33 or 34 when dependent on any one of claims 24 to 29, wherein the baffle extends from a rear of the humidifier liquid chamber to a substantially vertical face of the step.

36. The humidifier liquid chamber according to claim 33 or 34 when dependent on any one of claims 24 to 29, wherein the baffle extends from a rear of the humidifier liquid chamber towards a substantially vertical face of the step, and terminates proximal to a central axis of the humidifier liquid chamber.

37. The humidifier liquid chamber according to any one of claims 1 to 10 or 18 to 36, wherein the humidifier liquid chamber has a substantially cylindrical shape.

38. The humidifier liquid chamber according to claim 37, wherein the humidifier liquid chamber tapers towards a centre of the humidifier liquid chamber from a base of the humidifier liquid chamber to a top of the humidifier liquid chamber.

39. The humidifier liquid chamber according to any one of claims 1 to 10 or 18 to 38, comprising a heat conductive base.

40. The humidifier liquid chamber according to claim 38 or 39, wherein the base of the humidifier liquid chamber is removable from a body of the humidifier liquid chamber.

41. The humidifier liquid chamber according to claim 40, comprising one or more base removal features to assist with removing the base of the humidifier liquid chamber from the body of the humidifier liquid chamber.

42. The humidifier liquid chamber according to claim 41, wherein the one or more base removal features is/are located between a lower flange of the body of the humidifier liquid chamber and an outwardly extending flange of the base of the humidifier liquid chamber.

43. The humidifier liquid chamber according to claim 42, wherein the one or more base removal features comprises a slot.

44. The humidifier liquid chamber according to any one of claims 1 to 10 or 18 to 43, comprising a shoulder between the first and second base unit connection ports.

45. The humidifier liquid chamber according to claim 44, wherein the shoulder extends beyond exterior faces of the first and second base unit connection ports.

46. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 1 to 45, wherein one of the base unit connection ports is an inlet port and the other of the base unit connection ports is an outlet port.

47. A humidifier liquid chamber or a humidifier liquid chamber manifold comprising:

first and second base unit connection ports for connecting to a breathing assistance apparatus base unit;

wherein the base unit connection ports are substantially parallel to each other;

wherein each of the base unit connection ports comprises at least two sealing portions configured to form at least two seals with a portion of the breathing assistance apparatus base unit when connected to the breathing assistance apparatus base unit.

48. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 47, wherein the two sealing portions are separated by a distance of about 5 mm to about 7 mm.

49. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 48, wherein the two sealing portions are separated by a distance of about 5.5 mm to about 6.5 mm.

50. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 47 to 49, wherein each base unit connection port comprises an internal taper such that the base unit connection port narrows from a terminal end of the port towards an opposite end of the base unit connection port.

51. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 50, wherein an inner diameter of a first one of the sealing portions proximal to the terminal end of the base unit connection port is about 0 mm to about 0.6 mm greater than an inner diameter of a second one of the sealing portions distal the terminal end of the base unit connection port.

52. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 51, wherein the inner diameter of the first one of the sealing portions is less than about 25.6 mm.

53. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 52, wherein the inner diameter of the second one of the sealing portions is less than about 25.4 mm.

54. The humidifier liquid chamber according to any one of claims 47 to 53, wherein each base unit connection port comprises a central axis that is at least about 85 mm above a lower surface of a body of the humidifier liquid chamber.

55. The humidifier liquid chamber according to claim 54, wherein the central axes of the base unit connection ports are at least about 88 mm above the lower surface of the body of the humidifier liquid chamber.

56. The humidifier liquid chamber according to claim 54 or 55, wherein the lower surface is defined by an upper edge of a lower flange of the body of the humidifier liquid chamber.

57. The humidifier liquid chamber according to claim 56, wherein the lower flange is configured to engage with one or more retaining features in a breathing assistance apparatus base unit to assist with retaining the humidifier liquid chamber in engagement with the breathing assistance apparatus base unit.

58. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 47 to 57, wherein each base unit connection port is cylindrical.

59. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 47 to 58, wherein each base unit connection port is configured to receive a complementary port of a breathing assistance apparatus base unit.

60. The humidifier liquid chamber according to any one of claims 47 to 59, comprising flow tubes extending into the humidifier liquid chamber from the first and second base unit connection ports.

61. The humidifier liquid chamber according to claim 60, comprising a baffle in the interior of the humidifier liquid chamber and between openings of the flow tubes.

62. The humidifier liquid chamber according to claim 61, wherein the baffle extends downward from a roof of the humidifier liquid chamber and terminates above a maximum liquid fill level of the humidifier liquid chamber.

63. The humidifier liquid chamber according to claim 61, wherein the baffle extends downward from a roof of the humidifier liquid chamber and terminates at or below a maximum liquid fill level of the humidifier liquid chamber.

64. The humidifier liquid chamber according to any one of claims 61 to 63, wherein a roof of the humidifier liquid chamber is sloped so as to be substantially non-horizontal in use.

65. The humidifier liquid chamber according to claim 64, wherein at least one of the roof, the baffle, and wall(s) of the humidifier liquid chamber are configured to direct gases exiting the opening of the flow tube associated with the first base unit connection port toward and over a surface of liquid in the humidifier liquid chamber.

66. The humidifier liquid chamber according to any one of claims 47 to 65, comprising a step in the humidifier liquid chamber.

67. The humidifier liquid chamber according to claim 66, wherein a base of the step is located at least partly below the first and second base unit connection ports.

68. The humidifier liquid chamber according to claim 66 or 67 when dependent on any one of claims 61 to 65, wherein the baffle extends from a rear of the humidifier liquid chamber towards a substantially vertical face of the step, and terminates proximal to a central axis of the humidifier liquid chamber.

69. The humidifier liquid chamber according to claim 68, wherein a distance between a forward edge of the baffle and the substantially vertical face of the step is at least about 20 mm.

70. The humidifier liquid chamber or humidifier liquid chamber manifold according to any one of claims 47 to 69, wherein the first and second base unit

connection ports define respective axes, and wherein the first and second base unit connection ports are separated by a port separation distance between the axes, and wherein the port separation distance is between about 35 mm and about 45 mm.

71. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 70, wherein the port separation distance is between about 38 mm and about 42 mm.

72. The humidifier liquid chamber or humidifier liquid chamber manifold according to claim 71, wherein the port separation distance is about 40 mm +/-0.6mm