Positive airway pressure devices, neonatal fluidic resuscitator devices, and methods

Abstract

Various examples are provided related to positive airway pressure (PAP) devices, neonatal fluidic resuscitator devices, and methods thereof. In one example, a PAP device includes a body with an inlet to receive supplied gas, a venturi nozzle, an entrainment passage, a primary nozzle, an exhaust spillway, a diffuser, and an outlet to enable an expanded mixture of gas and entrained air to exit the device. Each of the venturi nozzle, entrainment passage, primary nozzle, exhaust spillway, diffuser, and outlet has a rectangular cross-section. In another example, a neonatal fluidic resuscitator device includes an inlet body portion with an inlet port and an inlet channel, an outlet body portion with an outlet port and an outlet channel, and a rotatable cartridge including fluid passage chambers that can selectively align with the inlet channel and the outlet channel to achieve a defined peak inspiratory pressure (PIP) for different neonate sizes.

Description

Docket: 292006-2140POSITIVE AIRWAY PRESSURE DEVICES, NEONATAL FLUIDIC RESUSCITATOR DEVICES, AND METHODSCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to, and the benefit of, U. S. provisional application entitled “Positive Airway Pressure Devices and Methods” having serial no. 63 / 722,993, filed November 20, 2024, and U. S. provisional application entitled “Neonatal Fluidic Resuscitator Devices and Methods” having serial no. 63 / 861,571, filed August 11, 2025, both of which are hereby incorporated by reference in their entireties.BACKGROUND

[0002] Positive airway pressure (PAP) is a mode of respiratory ventilation used in hyperinflation therapy. Hyperinflation therapy is used to prevent or reverse atelectasis, reduce air trapping in obstructive diseases, aid in mobilizing retained secretions, and optimize inhaled drug delivery. The flow of gas to a patient during PAP ventilation is typically regulated using a PAP device that is positioned between a gas source, such as a pressurized oxygen source, and a patient interface, such as a tube or a mask. The PAP device is designed to maintain a desired positive pressurization of the patient’s respiratory system throughout the respiratory cycle.

[0003] There are two primary types of PAP devices in use today: threshold resistors and flow resistors. Threshold resistors incorporate moving parts, such as spring-loaded valves. Although threshold resistors exhibit relatively high accuracy in maintaining the desired positive pressure, they are undesirably expensive to manufacture. While flow resistors have no moving parts and, therefore, are less expensive to manufacture, flow resistors typically lack the accuracy of threshold resistors.Docket: 292006-2140BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.

[0005] FIG. 1 A is a perspective view of a first example of a fluidic positive airway pressure device, in accordance with various embodiments of the present disclosure.

[0006] FIG. 1B is a side cross-sectional view of the fluidic positive airway pressure device of FIG. 1A, in accordance with various embodiments of the present disclosure.

[0007] FIG. 1C illustrates parameters of a first embodiment of the fluidic positive airway pressure device of FIGS. 1A and 1B (designated V13), in accordance with various embodiments of the present disclosure.

[0008] FIG. 2A is a side cross-sectional view of a second example of a fluidic positive airway pressure device, in accordance with various embodiments of the present disclosure.

[0009] FIG. 2B illustrates parameters of a second embodiment of the fluidic positive airway pressure device of FIG. 2A (designated V14), in accordance with various embodiments of the present disclosure.

[0010] FIG. 3A is a side cross-sectional view of a third example of a fluidic positive airway pressure device, in accordance with various embodiments of the present disclosure.

[0011] FIG. 3B illustrates parameters of a third embodiment of the fluidic positive airway pressure device of FIGS. 3A (designated V15), in accordance with various embodiments of the present disclosure.

[0012] FIG. 4A is a graph that shows pressure and volume tracings of a commercially available PAP device (AccuPAP, Pulmodyne, Inc.), in accordance with various embodiments of the present disclosure.Docket: 292006-2140

[0013] FIG. 4B is a graph that shows pressure and volume tracings of the 3D printed third example of the fluidic positive airway pressure device, in accordance with various embodiments of the present disclosure.

[0014] FIG. 5 is a perspective view of an example of a neonatal fluidic resuscitator device, in accordance with various embodiments of the present disclosure.

[0015] FIG. 6A is a cross-sectional side view of the neonatal fluidic resuscitator device of FIG. 5, in accordance with various embodiments of the present disclosure.

[0016] FIG. 6B is a cross-sectional vertical view of the neonatal fluidic resuscitator device of FIG. 5, in accordance with various embodiments of the present disclosure.

[0017] FIG. 6C is a cross-sectional perspective view of the neonatal fluidic resuscitator device of FIG. 5, in accordance with various embodiments of the present disclosure.

[0018] FIGS. 7A and 7B are end and perspective views of an example of a rotatable cartridge of the neonatal fluidic resuscitator device of FIG. 5, in accordance with various embodiments of the present disclosure.

[0019] FIG. 7C illustrates examples of fluid passage chambers of the rotatable cartridge of FIGS. 7A and 7B, in accordance with various embodiments of the present disclosure.

[0020] FIG. 8A illustrates an end view of a rotatable cartridge and views of fluid passage chambers of a fabricated neonatal fluidic resuscitator device, in accordance with various embodiments of the present disclosure.

[0021] FIG. 8B illustrates an example of measured airway pressure and tidal volume tracing for 1kg fluid passage chamber, in accordance with various embodiments of the present disclosure.DETAILED DESCRIPTION

[0022] Disclosed herein are various examples related to positive airway pressure (PAP) devices, neonatal fluidic resuscitator devices, and methods thereof. Reference will now be made in detail to the description of the embodiments as illustrated in the drawings, wherein like reference numbers indicate like parts throughout the several views.Docket: 292006-2140

[0023] It can be appreciated that it would be desirable to have positive airway pressure (PAP) devices that have no moving parts and, therefore, are less expensive to manufacture, but that exhibit the accuracy of threshold resistors in maintaining a desired positive pressurization of a patient’s respiratory system. Disclosed herein are fluid PAP devices, or FPAP devices, that achieve those goals. In some embodiments, an FPAP device comprises rectangular flow passages through which gas delivered to the device and air entrained into the device flows prior to delivery to a patient interface. The passages are “rectangular” in that they each have rectangular cross-sections in planes perpendicular to the directions of gas flow instead of the circular cross-sections of conventional PAP devices. In some embodiments, an FPAP device includes a rectangular venturi nozzle that delivers gas supplied to the device to a rectangular primary nozzle, which is also fed by one or more rectangular entrainment passages and that delivers the gas and entrained air to a rectangular diffuser, which then exits the device through a rectangular outlet upstream of the patient interface. In some embodiments, the FPAP device further includes one or more rectangular exhaust spillways that is / are used to exhaust gas exhaled by the patient. In testing, embodiments of such FPAP devices, which comprise no moving parts, were determined to maintain desired airway pressures as well as, and in some cases better than, commercially available threshold resistors.

[0024] In the following disclosure, various specific embodiments are described. It is to be understood that those embodiments are example implementations of the disclosed inventions and that alternative embodiments are possible. Such alternative embodiments include hybrid embodiments that include features from different disclosed embodiments. All such embodiments are intended to fall within the scope of this disclosure.

[0025] FIGS. 1A and 1B illustrate a first embodiment of an FPAP device 10 in accordance with this disclosure. Beginning with FIG. 1A, the device 10 comprises a body 12 that is unitarily constructed from a single piece of material, such as a polymer or metal material. In some embodiments, the body 12 can be formed using an additive manufacturing (e.g., three-dimensional (3D) printing) process, an injection molding process, or any other process withDocket: 292006-2140 which a component can be formed as a continuous piece of material. As is apparent from FIG.1A, the body 12 includes a proximal or inlet end 14 and a distal or outlet end 16. Adjacent the inlet end 14, the body 12 comprises a generally frustoconical portion 18, and adjacent the outlet end 16, the body comprises a generally cylindrical portion 20. The inlet end 14 is configured to connect to a tube that is in fluid communication with a source of pressurized gas, such as oxygen, while the outlet end 16 is configured to connect to a component that is in fluid communication with a patient interface, such as a nose or mouth tube or a face mask.

[0026] FIG. 1B is a side cross-sectional view of the FPAP device 10 visible when the device is vertically bisected through its central longitudinal axis CL. As such, the figure shows each of multiple internal flow passages formed within the device. Beginning from the left side of the figure, the device 10 includes an inlet port 22 through which pressurized gas can enter the device. The inlet port 22 leads to an inlet passage 24, which, along with the inlet port forms what may be referred to as an “inlet” of the device 10. The inlet, in turn, leads to a venturi nozzle 26 that includes a first nozzle outlet 28. Notably, each of the venturi nozzle 26, and first nozzle outlet 28 has a rectangular geometry (i.e., “is rectangular”), meaning that each has a rectangular cross-section in a plane perpendicular to the direction of gas flow, that direction being coincident with the central longitudinal axis C. Given that each of those features is rectangular, each is defined by four walls or surfaces, including a top wall, a bottom wall, a first lateral (e.g., left-side) wall, and second lateral (e.g., right-side) wall. As the venturi nozzle 26 forms a straight passage, its walls are planar and orthogonal relative to the other walls.

[0027] Continuing with FIG. 1 B, the FPAP device 10 further includes a first or top entrainment port 30 and a second or bottom entrainment port 32, which lead to a first or top entrainment passage 34 and a second or bottom entrainment passage 36, respectively. As with the other features described above, both entrainment ports 30, 32 and both entrainment passages 34, 36 are rectangular and, therefore, defined by four walls. While the lateral walls of the entrainment passages 34, 36 are planar, the top and bottom walls of the passages are curved, each extending both radially inward toward the central longitudinal axis CLof the device 10 as well as distally toward the outlet end 16 of the device. As can be appreciatedDocket: 292006-2140 from FIG. 1B, the entrainment passages 34, 36 are symmetrical relative to a horizontal plane that contains the central longitudinal axis CLand join each other at a point near the outlet 28 of the venturi nozzle 26 to form a first central passage 38 that functions as an inlet to a primary nozzle 40 of the device 10 that includes a second nozzle outlet 42. Like other features described above, the central passage 38, primary nozzle 40, and second nozzle outlet 42 are each rectangular and defined by four orthogonal planar walls.

[0028] With further reference to FIG. 1B, the FPAP device 10 additionally includes an exhaust spillway port 44 that leads to an exhaust spillway passage 46, which together form what may be referred to as an “exhaust spillway.’’ The exhaust spillway extends to a second central passage 48 near the second nozzle outlet 42 that is partly defined by a planar bottom wall 50 that is parallel with a horizontal plane that contains the central longitudinal axis CL. Both the exhaust spillway port 44 and the exhaust spillway passage 46 are rectangular and defined by four planar walls. A proximal wall 52 of the exhaust spillway passage 46 lies in a plane that is perpendicular to the horizontal plane that contains the central longitudinal axis CLof the device 10, while a distal wall 54 of the spillway passage 46 lies in a diagonal plane that forms an acute angle a with the horizontal plane. In some embodiments, the angle a is approximately 40 to 60 (e.g., 50) degrees. As shown in FIG. 1B, the distal wall 54 diverges from the proximal wall 52 as the exhaust spillway passage 46 is traversed from the exhaust spillway port 44 toward the central longitudinal axis CL.

[0029] Downstream of the second central passage 48 is a rectangular diffuser passage 56, or simply “diffuser,” which expands flow and is also defined by four planar walls. In this case, the lateral walls are orthogonal relative to the bottom wall 58, which is contiguous with the planar bottom wall 50 of the second central passage 48 and, therefore, is also parallel to the horizontal plane that contains the central longitudinal axis CL. The top wall 60 of the diffuser passage 56, however, diverges away from the bottom wall 58 as the diffuser passage is traversed toward the outlet end 16 of the FPAP device 10. In some embodiments, the top wall 60 forms an acute angle b of approximately 4 to 8 (e.g., 6) degrees with the horizontal plane that contains the central longitudinal axis CL. The diffuser passage 56 terminates in an outletDocket: 292006-2140 port 62, or simply “outlet,” from which gas and entrained air can exit the device 10 and flow into or toward the patient interface.

[0030] The above-described configuration of the FPAP device 10 enables the device to function as a pneumatically driven fluidic amplifier that, like existing flow resistors, provides adjustable PAP with no moving parts. The device 10 operates in a manner in which, as the outlet pressure decreases, all flow is directed to the outlet end 16 of the device to raise the outlet pressure. As the outlet pressure rises, the motive flow jet output from the primary nozzle 40 separates from the bottom wall 58 (a control surface) and gas is exhausted from the device 10 via the exhaust spillway. As the outlet pressure rises further, most of the motive flow is diverted to the exhaust spillway and the outlet airway pressure is maintained at or near the desired positive pressure. Notably, the above functionality is achieved in significant part because of the rectangular geometry utilized for the various passages of the FPAP device 10. The interaction of fluids with the walls (surfaces) of the passages, especially the wettability of such surfaces, can differ significantly between rectangular and circular passages. In particular, rectangular passages provide larger planar surfaces that can enhance adhesion due to the presence of more extensive contact areas. It has been determined that rectangular ducts are preferrable in the construction of a PAP device because of their favorable flow characteristics and enhanced fluid-surface interactions. In addition, rectangular ducts appear to enable more precise control overflow patterns, which makes the designing of device characteristics more logical and predictable.

[0031] The entrainment passages 34, 36 entrain ambient air around the outlet 28 of the venturi nozzle 26, which has a multiplier effect on the motive air jet flow rate and, as a consequence, the FPAP device 10 uses a lower volumetric flow rate of gas than the volumetric flow rate of gas that is delivered to the patient by the device. Using a solid-state design having no moving parts or electronics, the device 10 maintains an airway pressure that is highly consistent throughout the patient breathing cycle. That result is achieved at least in part due to the configuration of the exhaust spillway that, in addition to enabling exhaust of exhaled gasDocket: 292006-2140to the atmosphere, doubles as an air ingress passage during large patient inhalations and when high flow rates are used.

[0032] The various passages of the FPAP device 10 can be sized to either maximize velocities for entrainment purposes or sized to generate required pressure values at desired flow rates. The motive flow jet output from the primary nozzle 40 is tangential to the bottom wall 58 of the diffuser passage 56 and, due to the Coanda effect, adheres to that wall as it enters the passage. While the motive flow jet adheres to the bottom wall 58, some degree of jet dispersion occurs towards the outlet port 62, which results in entrainment through the exhaust spillway into the airway. Depending upon the stage of the respiratory cycle, this can result in gas being spilled out of the exhaust spillway, which appears to assist in controlling the airway pressure.

[0033] FIG. 2A illustrates a second embodiment of an FPAP device 100. The device 100 is similar in design to the FPAP device 10 of FIGS. 1A and 1B and, therefore, comprises many of the same features as that device, which are identified by the same reference numerals, and which will not be described again. Unlike the device 10, however, the device 100 has a semi-cylindrical trough or groove 102 formed in the bottom wall 104 of the second central passage 48 adjacent the outlet 42 of the primary nozzle 40 and opposite the exhaust spillway port 44. This groove 102 has a longitudinal axis that is transverse to the motive flow jet output from the primary nozzle 40. The groove 102 increases the adhesion of the motive flow jet to the bottom wall 104 (a lower control surface), but also enables the jet to more easily separate from that wall. In testing, the groove 102 appeared to stabilize and smooth the operation of the device 100. It is hypothesized that the curvature of the groove 102 may enable a breakaway pocket of localized recirculation vortices to develop, which enables gas to more easily toggle from supplying gas and entrained air to the patient to exhausting gas exhaled by the patient, thereby more accurately maintaining airway pressure.

[0034] FIG. 3A illustrates a third embodiment of an FPAP device 200. The device 200 is also similar in design to the FPAP device 10 of FIGS. 1A and 1B and, therefore, comprises many of the same features as that device, which are identified by the same referenceDocket: 292006-2140numerals, and which will not be described again. Unlike the FPP device 10, however, the device 200 has two exhaust spillways defined by two rectangular entrainment ports 202 and 204 that lead to two rectangular exhaust spillway passages 206 and 208, respectively. The two exhaust spillways are symmetrical to each other relative to the horizontal plane that contains the horizontal plane that contains the central longitudinal axis C and join each other at a point near the outlet 42 of the primary nozzle 40 upstream of a rectangular diffuser passage 210 (or “diffuser”). In this embodiment, the diffuser passage 210 comprises a top wall 212 and a bottom wall 214 that both diverge from each other as the diffuser passage 210 is traversed toward the outlet port 52 at an angle q relative to the horizontal plane that contains the central longitudinal axis CL, such that the diffuser is symmetrical relative to that plane. In some embodiments, the angle q is approximately 4 to 8 (e.g., 6) degrees. The intention behind this embodiment is to reduce inhalation effort for the patient, which is achieved by duplicating the exhaust spillway while maintaining a primary nozzle 40 and diffuser passage 210 geometry similar to that of the FPAP device 10.

[0035] Each of the above-described FPAP device embodiments were fabricated using 3D printing and tested to compare their performance to popular PAP devices available in the market. In particular, the FPAP device embodiments were compared with the AccuPAP™ threshold resistor and the VersaPAP™ flow resistor. The results of this testing are presented in TABLE 1 below.Docket: 292006-2140CONFiDt S H Typ ei Mean Paw {rmrHSQJ % within Oexios e of PAPres Flow Flow FS02 istor Seting {JpB»} (ipm) {%}High Low High Low5 83 (0.03) 0.3 (0.02} 108% 100%10 85(0.04? 11.3 (0,83} 108% 100%10 51.3 34.7 AccuFAP Weshoic! IS 16,8 (0.08) 17.6 (0.01} 100% 0%30 23.0(0,01) 31,9 (0.02) 0% 100%Combined 14.0 (8.36} 78%s" 7 4.4 (0.01) 4,5 (0.01} 108% 108^ 268 10 10 8.6(0.01} S.1 (0.02) 1t»% 36,6 40,9 VersaPAP FW 15 12 13,1 {0.01) 13.2 (0,82} 100% 100% 44.1 40.820 14 17,7(0.01) 17.8 (0,14} 0% 0% 51.7 403 tXKTrowa 11.1 (4.83) 75%5 5 §4(0.02) 5.3 (001} 108% 100% 34,0 37.0 10 6 7.7 (002} 8,4 (0.02) 0% 100% 29.6 38.0 Pfcw 15 a 13.1 {0,04} 14,6 (0.04} 100% 100% 38? 35,9 ¥1328 9 18,4(8.04} 17.8 (0,84) 0% 0% 43.1 35.8 Gemhined 11.0 (4.48} 82.5%5 4 38(0.05} 3.0 (0.01) 100% 100% 2U 3S.0 10 6 8.8 (0.05) 8.4 (0.01} 108% 108% 32.8 34,4 V14 rfcw 15 8 14.7 (8.09) 14.8 (0,83) 108% 10G% 42.3 34. S 30 9 17,9(0,45) 17.3 (0.05) 28.5% 0% 48.3 34,9 Combined 11,3(5.4?) 78,8%5 a 3.5(0.01} 3.7 (8.91) 180% 100% 20 33.0 10 s 9,7(0.02) 18.1 (0,05) 108% 100% 31 33,8 ¥15 Fipw 15 8 13,6(0,04) 13,9 (0.04) 100% 100% 35 34.020 7 17.8(0.05} 17.6(0,08} 0% 0% 47 33,0Combined 11,2 (5.20) 75.0TABLE 1: Performance comparison of FPAP devices with AccuPAP™ and VersaPAP™ devices.

[0036] In TABLE 1, the first, second, and third embodiments of the FPAP device are designated V13, V14, and V15, respectively. The parameters of those three FPAP devices (V13, V14, and V15) are provided in FIGS. 1C, 2B, and 3B, respectively. All dimensions are in mm. The table identifies the airway pressure the device is intended to maintain expressed in centimeters of water (“PAP setting”), the flow rate of oxygen gas supplied to the devices expressed in liters per minute (“Set Flow (Ipm)”), the low, high, and mean airway pressures actually maintained by the devices expressed in centimeters of water (“Mean Paw (cmH2O)”), the ability of each device to maintain a pressure that is within + / - 2 cmH2O of the intended (set) pressure expressed as a percentage (“% within + / - 2”), the total flow of gasDocket: 292006-2140supplied to the patient expressed in liters per minute (“Total Flow (Ipm)”), and the percentage of that flow that comprised oxygen gas (“FIO2 (%)”). As can be appreciated from the results presented in the table, the FPAP devices performed well in maintaining an intended airway pressure with the third embodiment (V15) equaling the performance of the AccuPAP™ threshold resistor and VersaPAP™ flow resistor, and the second embodiment (V14) exceeding the performance of both commercially available devices. These results suggest that the high accuracy of threshold resistors, which incorporate moving parts, can be achieved or exceeded by FPAP devices having no moving parts and, therefore, that are significantly less expensive to manufacture. Table 1 also illustrates that the FPAP devices are highly efficient in that, at each pressure setting, the devices used less oxygen gas than the commercially available devices, especially the VersaPAP™ flow resistor.

[0037] With respect to FIGS. 4A and 4B, both devices were tested using the ASL 5000 (IngMar Medical) in the following flow conditions: peak inspiratory flow 21.4 L / min and peak expiratory flow 12.7 L / min breathing characteristics. Both devices were set to achieve 5, 10, 15, and 20 cmH2O in incremental and decremental steps. Flow was recorded on a calibrated flow meter (Fluke) prior to experiment. Each device was tested for 50 breaths. + / -2 cmH2O of desired target PAP was considered significant. The top chart 403 (Blue) is recorded pressure (cmH2O) within the lung simulator. The red tracing 406 (bottom) is the volume measurements (ml) within the lung simulator. Each experiment started with no PAP and each step labeled with the flow rate required to create a PAP setting of 5, 10,15, and 20 cmH2O in incremental and decremental steps.

[0038] In summary, the disclosed FPAP devices are capable of producing the same therapeutic pressures and characteristics as commercially available devices or better, improve reliability, and can be manufactured at a fraction of the cost of devices that require moving parts.

[0039] In the U. S., newborn mortality grew by 3% between 2021 and 2022, based on provisional data on infant mortality. The Commonwealth Fund reported in 2020 that the U. S. infant mortality rate was over three times higher than in other high-income countries.Docket: 292006-2140Additionally, the American Association of Family Physicians notes that one of every 61 U. S births occurs outside of a hospital. Out-of-hospital deliveries are associated with elevated morbidity and mortality rates for both babies and mothers, often conducted by personnel with minimal medical training and limited experience. Newborns possess unique and fragile respiratory systems, and insufficient ventilation can cause hypercapnia and severe hypoxia, leading to brain damage or death. Conversely, hyperventilation can result in respiratory alkalosis, vasoconstriction, and reduced cerebral perfusion, increasing the risk of brain injury. These factors underscore the need for precise and consistent mechanical ventilation techniques during neonatal resuscitation. Furthermore, manual resuscitations within Emergency Medical Services (EMS) often result in breaths that are outside safe ranges for neonatal lungs. Recent NIH-supported research has identified significant gaps and unmet needs for rescue breathing in various acute settings, including EMS.

[0040] While 10% of newborns globally require resuscitation at birth, delivering safe and effective emergency resuscitation remains a worldwide challenge. The current standard tool for rescue breathing is a manual device known as a bag valve mask (BVM), which can be labor-intensive and complex due to factors like the required short inspiratory times, fast respiratory rates, small tidal volumes, mask leaks and airway obstructions to name a few. Inadequate mechanical ventilation during neonatal resuscitation can lead to injury and even death. This disclosure presents a fluidic-powered automatic neonatal ventilator operating without electronic components that can be used for neonatal resuscitation. Using principles of fluid dynamics — particularly the Coanda effect — the neonatal fluidic resuscitator device can overcome the shortcomings of manual ventilation and ensure precise and consistent ventilation, offering potential use in emergency or resource-limited settings.

[0041] FIG. 5 illustrates an example of a neonatal fluidic resuscitator device 500 in accordance with this disclosure. The body of the neonatal fluidic resuscitator device 500 comprises an inlet body portion 503, an outlet body portion 506 and a rotatable cartridge 509 disposed between the inlet and outlet body portions 503 and 506. The inlet body portion 503, outlet body portion 506, and / or cartridge 509 of the body can be constructed fromDocket: 292006-2140polymer, metal, or other suitable material. In some embodiments, the inlet body portion 503, outlet body portion 506, and / or cartridge 509 can be formed using an additive manufacturing (e.g., three-dimensional (3D) printing) process, an injection molding process, or any other process with which a component can be formed as a continuous piece of material.

[0042] As shown in FIG. 5, the neonatal fluidic resuscitator device 500 includes a proximal or inlet end 512 and a distal or outlet end 515. Adjacent the inlet end 512, the inlet body portion 503 comprises a generally frustoconical or tapered portion 518, and adjacent the outlet end 515, the body comprises a generally cylindrical portion 521. The inlet end 512 is configured to connect to a tube that is in fluid communication with a source of pressurized gas, such as oxygen, while the outlet end 515 is configured to connect to a component that is in fluid communication with a patient interface, such as a nose or mouth tube or a face mask.

[0043] Referring next to FIGS. 6A-6C, shown are cross-sectional views of the neonatal fluidic resuscitator device 500 of FIG. 5. As illustrated in the cross-sectional side view of FIG.6A, the inlet body portion 503 of the neonatal fluidic resuscitator device 500 comprises an inlet port 603 at the inlet end 512 and an inlet channel 606 extending between the inlet port 603 and a first side of the rotating cartridge 509. The outlet body portion 506 comprises an outlet port 609 and an outlet channel 612 extending between the outlet port 609 and a second side of the rotating cartridge 509. The inlet body portion 503 can also include a post or shaft extension 615 that extends outward from distal side (or surface) of the inlet body portion 103 (opposite the proximal or inlet end 512), which can be configured to engage with the outlet body portion 509 (or with a proximal side (or surface) of the outlet body portion 509) of the neonatal fluidic resuscitator device 500 as shown in FIG. 6A.

[0044] The post or shaft extension 615 can support the rotatable cartridge 509 between the inlet and outlet body portions 503 and 506 of the neonatal fluidic resuscitator device 500. The post or shaft extension 615 can be formed with a shoulder or step for proper spacing between the inlet and outlet body portions 503 and 506 for rotation of the cartridge 509. The surface of the post or shaft extension 615 can also include a coating or lubrication forDocket: 292006-2140smooth rotation of the cartridge 509. A pin or other fastener can be inserted through the outlet body portion 506 and the post or shaft extension 615 into the inlet body portion 503 to hold the neonatal fluidic resuscitator device 500 together as shown in FIG. 6A. In other implementations, the post or shaft extension 615 can extend outward from a proximal side (or surface) of the outlet body portion 506 of the neonatal fluidic resuscitator device 500 and be configured to engage with the inlet body portion 503 (or with the distal side (or surface) of the inlet body portion 503) as can be understood by one of skill in the art.

[0045] FIG. 6B shows a cross-sectional vertical view of the neonatal fluidic resuscitator device 500. The pin or fastener is not shown inserted through the post or shaft extension 615. An opening on the side of the neonatal fluidic resuscitator device 500 allows the pin or fastener to be secured in position. As can be seen in FIG. 6B, the inlet channel 606 is directed around the post or shaft extension 615. FIG. 6C shows a cross-sectional perspective view of the neonatal fluidic resuscitator device 500. As illustrated, the inlet channel 606 initially extends from the inlet port 603 before being diverted along a side of the inlet body portion 503 until the inlet channel 606 is again angled to align with a fluid passage chamber of the rotatable cartridge as will be discussed. As illustrated, the inlet channel 606 and outlet channel 612 can be substantially aligned on opposite sides of the cartridge 509 to allow gas to flow between the inlet port 603 and outlet port 609. The outlet body portion 506 can also include one or more passages or channels 618 extending from the outlet port 609 for a pressure manometer, emergency relief valve, and / or an asphyxiation valve as illustrated in FIG. 6B. Other sensing and monitoring can also be incorporated into the neonatal fluidic resuscitator device 500 as needed.

[0046] Referring next to FIGS. 7A-7C, shown is an example of the rotatable cartridge 509. The rotatable cartridge 509 can comprise a plurality of fluid passage chambers 703 distributed about an axial opening 706 through which the post or shaft extension 615 (FIGS.6A-6C) extends. The inner surface 709 of the axial opening 706 can include a coating or lubrication for smooth rotation of the cartridge 509. The outer surface of the cartridge 509 can include a texture, ribs, or other objects to facilitate rotation of the cartridge 509 about theDocket: 292006-2140post or shaft extension 615. One or both end surfaces of the cartridge 509 and one or both end surfaces of the inlet body portion 503 and / or outlet body portion 506 can be configured to facilitate selective rotational alignment of the fluid passage chambers 703 with the inlet and outlet channels 606 and 612 (FIGS. 6A and 6C). The surfaces of the inlet and outlet body portions 503 and 506 can include gaskets, o-rings, or other sealing to prevent fluid leakage between the inlet and outlet channels 606 and 612 and the aligned fluid passage chamber 703 (see, e.g., FIGS. 6A and 6C). The sealing can be designed to allow for rotation of the cartridge 509 without turning off the fluid supply, thus allowing for selection or variation of the fluid passage chambers 703 during operation of the neonatal fluidic resuscitator device 500.

[0047] FIG. 7A is an end view illustrating an example of a cartridge 509 comprising four fluid passage chambers 703 including three fluidic-powered ventilators designed to target 3 size neonates (1, 2, 3 Kg) to achieve a Peak Inspiratory Pressure (PIP) of 18 and positive end expiratory pressure (PEEP) of 4 and an l: E ratio of 1:2 at flows rates of 1, 1.5 and 2 L / min and a fourth channel for fluidic positive airway pressure (FPAP) to achieve a CPAP of 5 at 2L / min. In other implementations, a different number of fluid passage chambers 703 and combinations of channels can be utilized. FIG. 7B is a perspective view of the cartridge 509, which illustrates an example of the distribution of the fluid passage chambers 703 about the cartridge 509 and space available for one or more additional fluid passage chambers 703.

[0048] The neonatal fluidic resuscitator device 500 provides an efficient fluidic amplifier with no moving parts, that utilizes the Coanda effect to direct air flow to the patient. The specially designed nozzle employs the Bernoulli effect to create a high-velocity flow that generates low pressure around the nozzle, effectively diverting airflow to the inspiratory wall (e.g., the step 739 of FIG. 7C). Once the pressure reaches the preset peak inspiratory pressure (PIP) of 18 cmH2O, the built-up pressure disrupts the wall-attachment effect, causing the Bernoulli effect to redirect air to the expiratory channel (e.g., channel exhaust 727 of FIG. 7C). This allows the patient to exhale to a preset positive end expiratory pressure (PEEP) of 5 cmH2O, with the cycle repeating continuously. By providing threeDocket: 292006-2140different sizes in the rotatable cartridge 509, the neonatal fluidic resuscitator device 500 can serve a range of neonates from about 0.5 to about 4 kgs. The neonatal fluidic resuscitator device 500 can be adjusted to match the needs of the patient simply by rotating the cartridge 509, thus avoiding the delay of swapping out the device in potentially critical situations. The addition of a fluid passage chamber 703 with FPAP channel capability adds additional flexibility to the neonatal fluidic resuscitator device 500. The neonatal fluidic resuscitator device 500 can eliminate the manual aspect of ventilation traditionally done with a bag valve mask resuscitator; reduce or eliminate inconsistencies in airway pressure, respiratory rates, tidal volume and minute ventilation in a single use disposable device; and reduce gas consumption from 6-8 L / min of manual systems to 1-3 L / min motive flow.

[0049] FIG. 7C shows a cross-sectional view of the rotatable cartridge 509 illustrating fluid passage chambers 703 including examples of fluidic-powered ventilator channel designs to achieve a PIP (703a) and FPAP channel (703b). The bottom drawing illustrates elements of the fluid passage chamber 703a shown in the lower cross-section of the rotatable cartridge 509 and the top drawing illustrates elements of the fluid passage chamber 703b shown in the upper cross section of the rotatable cartridge 509. As shown in FIG. 7C, the fluid passage chamber 703a that is designed to achieve the PIP comprises a channel inlet 721, a channel outlet 724, and a channel exhaust 727. When the channel inlet 721 and channel outlet 724 are aligned with the inlet channel 603 and outlet channel 612, the fluid passage chamber 703a is configured to receive a supply of fluid (e.g., pressurized oxygen) at the channel inlet 721 via the inlet port 603 and inlet channel 603 and the channel outlet 724 leads to the outlet port 609 via outlet channel 612 (see FIG. 6A). In use, the fluid passage chamber 703a transitions fluid (e.g., air) flow from the channel outlet 724 to the channel exhaust 727, and vice-versa.

[0050] Referring to FIG. 7C, the fluid supply enters through channel inlet 721 and passes into a fluid expansion zone 730. The fluid narrows down and passes through a nozzle 733 that leads to a split or bifurcated path. The fluid expansion zone 730 can act as a flow stabilizer and disrupt any boundary layer may be established. In various embodiments,Docket: 292006-2140the nozzle can have a substantially uniform cross-sectional area and end at a transition surface 736. The nozzle 733 terminates at a step 739 and the transition surface 736, which may be a tapered or curved surface. Alternatively, the transition surface 736 may also be a step. The step 739 has a given step offset, which may impact the performance of the fluid passage chamber 703a. Similarly, the transition surface 736 may have a particular radius of curvature (e.g., particularly where the transition surface 736 meets the nozzle 733).

[0051] A splitter 742 can split the fluid pathways, such that the fluid may travel towards the channel outlet 724 or the channel exhaust 727. Various embodiments tune the splitter distance (i.e., the distance from the end of the nozzle 733 to the splitter 742) to achieve desired performance characteristics. In various embodiments, the splitter distance can be the distance from the step 739 to a proximal end of the splitter 742. The proximal end can define a splitter width. The nozzle 733 defines a central nozzle axis, which in various embodiments, can be the same as the central longitudinal axis of the fluid passage chamber 703a (see FIG. 70). The splitter 742 can be biased to one side (e.g., the splitter 742 is not aligned with the nozzle axis). Additional details regarding the fluid passage chambers 703a with fluidic-powered ventilator designed to achieve a Peak Inspiratory Pressure (PIP) can be found in U. S. Patent Application No. 18 / 908,372, filed October 7, 2024 (U. S. Pat. App. Publ. No. 2025 / 0135148, entitled “Fluidic Valve”), which is hereby incorporated by reference in its entirety.

[0052] FIG. 7C also illustrates the fluid passage chamber 703b with FPAP channel capability. The fluid passage chamber 703b comprises a passage inlet 751, a passage outlet 754, and a passage exhaust 757. When the passage inlet 751 and passage outlet 754 are aligned with the inlet channel 603 and outlet channel 612, the fluid passage chamber 703b is configured to receive a supply of fluid (e.g., pressurized oxygen) at the passage inlet 751 via the inlet port 603 and inlet channel 606 and the passage outlet 754 leads to the outlet port 609 via outlet channel 612. The fluid supply enters through passage inlet 751 and passes into a fluid expansion zone 760, which can act as a flow stabilizer and disrupt any boundary layer that may be established. The fluid expansion zone 760, in turn,Docket: 292006-2140can lead to a nozzle 763 that includes a nozzle outlet 766. Notably, each of the nozzle 763 and nozzle outlet 766 has a rectangular geometry (i.e., “is rectangular”), meaning that each has a rectangular cross-section in a plane perpendicular to the direction of gas flow, that direction being coincident with the central longitudinal axis CL of the nozzle 763. Given that each of those features is rectangular, each is defined by four walls or surfaces, including a top wall, a bottom wall, a first lateral (e.g., left-side) wall, and second lateral (e.g., right-side) wall. As the nozzle 763 forms a straight passage, its walls are planar and orthogonal relative to the other walls.

[0053] The fluid passage chamber 703b additionally includes the passage exhaust 757, which forms what may be referred to as an “exhaust spillway.” The exhaust spillway extends to a central passage 769 near the nozzle 363 that is partly defined by a bottom wall having a semi-cylindrical trough or groove formed adjacent the nozzle outlet 766 and opposite the passage exhaust 757. This groove has a longitudinal axis that is transverse to the motive flow jet output from the nozzle outlet 766. The groove increases the adhesion of the motive flow jet to the bottom wall (a lower control surface), but also enables the jet to more easily separate from that wall. In testing, the groove appeared to stabilize and smooth the operation of the fluid passage chamber 703b. It is hypothesized that the curvature of the groove may enable a breakaway pocket of localized recirculation vortices to develop, which enables gas to more easily toggle from supplying gas and entrained air to the patient to exhausting gas exhaled by the patient, thereby more accurately maintaining airway pressure. The passage exhaust 757 is rectangular and defined by four planar walls. A proximal wall 772 of the passage exhaust 757 lies in a plane that is perpendicular to the horizontal plane that contains the central longitudinal axis CLof the fluid passage chamber 703b (see FIG. 7C), while a distal wall 775 of the passage exhaust 757 lies in a diagonal plane that forms an angle with the horizontal plane.

[0054] Downstream of the central passage 369 is a rectangular diffuser passage 778, or simply “diffuser,” which expands flow. In this case, the lateral walls are orthogonal relative to the bottom wall, which is contiguous with the bottom wall of the central passage 769 and,Docket: 292006-2140therefore, is also parallel to the horizontal plane that contains the central longitudinal axis CL. The top wall of the diffuser passage 778, however, diverges away from the bottom wall as the diffuser passage is traversed toward the passage outlet 754. The above-described configuration of the fluid passage chamber 703b enables the neonatal fluidic resuscitator device 500 to function as a pneumatically driven fluidic amplifier that provides adjustable PAP with no moving parts. The fluid passage chamber 703b operates in a manner in which, as the outlet pressure decreases, all flow is directed to the outlet end 515 of the neonatal fluidic resuscitator device 500 to raise the outlet pressure. Additional details regarding the fluid passage chambers 703b with FPAP channel capability can be found in U. S. Patent Application No. 63 / 722,933, filed November 20, 2024 (entitled “Positive Airway Pressure Devices and Methods”), which is hereby incorporated by reference in its entirety.

[0055] Prototype neonatal fluidic resuscitator devices 500 were fabricated for testing and evaluation. Rapid prototyping was performed via 3D printing of a 3-channel device designed to target 3 nominally sized neonates (1, 2, 3 Kg) to achieve a Peak Inspiratory Pressure (PIP) of 18 and Positive End Expiratory Pressure (PEEP) of 4 cmFhO while producing appropriate breath characteristics. Using the ASL 5000 neonatal lung simulator set to 1-3kg lung characteristics, 15 channels built within 5 devices were tested. FIG. 8A illustrates an end view of a rotatable cartridge 509 and views of fluid passage chambers 703 of a fabricated neonatal fluidic resuscitator device 500. The examples of nozzle diameters (in mm) for the 3 nominally sized neonates (A = 1 Kg, B = 2 Kg, C = 3 Kg) and for the FPAP nozzle (D) are shown. Examples of the channel exhaust 727 widths are also illustrated. FIG.8B shows an example of the test results for channel 1 (A - designed for the 1 Kg neonate) airway pressure and tidal volume. The results are summarized in the table below. To deliver breathing characteristics suitable for neonates, the flow must be low which requires the channels to be very small. This impacts manufacturing tolerances and drives reproducibility of results.Docket: 292006-2140Channel PIP PEEP Delta Paw Vte (ml) RR Min. Vent l / E Insp. Time (cmH20) (cmH20) Pressure (cmH2O) (BPM) (sec) Goal 18 4 14 6 ml / kg 30-60 150 ml / Kg 0.3-0.4 0.3-0.518.5 14.5 9.1 13.3 [0.9] 32.0 420 [10.4] 0.27 0.39 lkg [0.13] 4 [0.85] [0.84] [0.44] 13 ml / Kg [6.3] 420 ml / Kg [0.154] [0.012]19.318.6 6.3 12.2 10.6 [0.45] 37.1 716 [14.6] 0.34 0.41 2 kg [0.27] [0.10] [0.24] [0.17] 9.7 ml / kg [1.2] 358 ml / Kg [0.013] [0.009]25.6 100218.1 6.7 11.5 11.4 [1.10] 39.3 [16.0] 0.42 0.453 kg [0.25] [0.41] [0.43] [0.25] 8.5 ml / kg [2.5] 334 ml / kg [0.048] [0.007]

[0056] It should be emphasized that the above-described embodiments of the present disclosure are merely possible examples of implementations set forth for a clear understanding of the principles of the disclosure. Many variations and modifications may be made to the above-described embodiment(s) without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.

[0057] The term "substantially" is meant to permit deviations from the descriptive term that don't negatively impact the intended purpose. Descriptive terms are implicitly understood to be modified by the word substantially, even if the term is not explicitly modified by the word substantially.

[0058] It should be noted that ratios, concentrations, amounts, and other numerical data may be expressed herein in a range format. It is to be understood that such a range format is used for convenience and brevity, and thus, should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. To illustrate, a concentration range of “about 0.1% to about 5%” should be interpreted to include not only the explicitly recited concentration of about 0.1 wt% to about 5 wt%, but also include individual concentrations (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.5%, 1.1%, 2.2%, 3.3%, and 4.4%) within the indicated range. The term “about” can include traditional rounding according toDocket: 292006-2140significant figures of numerical values. In addition, the phrase “about ‘x’ to ‘y’” includes “about x’ to about ‘y’”.

Claims

Docket: 292006-2140CLAIMSTherefore, at least the following is claimed:

1. A positive airway pressure device comprising:a body including an inlet configured to receive a supplied gas, a venturi nozzle downstream of the inlet configured to receive the gas from the inlet and eject it from a first nozzle outlet, an entrainment passage that extends to the first nozzle outlet configured to enable air to be entrained into the device, a primary nozzle downstream of the venturi nozzle and the entrainment passage configured to receive a mixture of gas and entrained air and to eject the mixture from a second nozzle outlet, an exhaust spillway that extends to the second nozzle outlet configured to enable gas to be exhausted from the device, a diffuser downstream of the primary nozzle and the exhaust spillway configured to expand the mixture of gas and entrained air, and an outlet configured to enable the expanded mixture of gas and entrained air to exit the device;wherein each of the venturi nozzle, entrainment passage, primary nozzle, exhaust spillway, diffuser, and outlet has a rectangular cross-section.

2. The device of claim 1, wherein the body includes a top entrainment passage and a bottom entrainment passage, each entrainment passage extending to the first nozzle outlet and being configured to enable air to be entrained into the device.

3. The device of any one of claims 1 and 2, wherein the exhaust spillway comprises a proximal wall that is perpendicular to a horizontal plane that contains a central longitudinal axis of the device and a diagonal wall that forms an acute angle with the horizontal plane.Docket: 292006-21404. The device of any one of claims 1-3, wherein the diffuser comprises a bottom wall that is parallel to a horizontal plane that contains a central longitudinal axis of the device and a top wall that forms an acute angle with the horizontal plane.

5. The device of any one of claims 1-4, wherein the body further includes a transverse semi-cylindrical groove formed in a bottom wall of a central passage adjacent the second nozzle outlet.

6. The device of any one of claims 1-5, wherein the body includes a top exhaust spillway and a bottom exhaust spillway, each exhaust spillway extending to the second nozzle outlet and being configured to enable gas to be exhausted from the device.

7. The device of any one of claims 1-6, wherein the diffuser comprises a top wall and bottom wall, each wall forming an acute angle with a horizontal plane that contains a central longitudinal axis of the device.

8. A neonatal fluidic resuscitator device, comprising:an inlet body portion comprising an inlet port and an inlet channel extending from the inlet port to a distal surface of the inlet body portion;an outlet body portion coupled to the inlet body, the outlet body portion comprising an outlet port and an outlet channel extending from a proximal surface of the outlet body portion to the outlet port; anda rotatable cartridge disposed between the distal surface of the inlet body portion and proximal surface of the outlet body portion, the rotatable cartridge comprising a plurality of fluid passage chambers configured to selectively align with the inlet channel and the outlet channel, the plurality of fluid passage chambersDocket: 292006-2140including a plurality of fluidic-powered ventilators configured to achieve a defined peak inspiratory pressure (PIP) for different neonate sizes.

9. The neonatal fluidic resuscitator device of claim 8, wherein the defined PIP is in a range from 15 to 30 cmH2O.

10. The neonatal fluidic resuscitator device of claim 9, wherein a positive end expiratory pressure (PEEP) is in a range from 3-8 cmH2O and an l: E ratio is in a range from 1:1.5-1:3.0.

11. The neonatal fluidic resuscitator device of claim 10, wherein the plurality of fluidic- powered ventilators achieve the defined PIP, PEEP, and l: E ratio for neonate sizes in a range from about 0.5kg to about 5kg.

12. The neonatal fluidic resuscitator device of any one of claims 8-11, wherein each of the plurality of fluidic-powered ventilators comprises a channel inlet, a channel outlet, and a channel exhaust, wherein selective alignment of a fluid passage chamber substantially aligns the channel inlet with the inlet channel and the channel outlet with the outlet channel.

13. The neonatal fluidic resuscitator device of any one of claims 8-12, wherein the rotatable cartridge rotates about a post or shaft extension between the distal surface of the inlet body portion and the proximal surface of the outlet body portion.

14. The neonatal fluidic resuscitator device of claim 13, wherein the post or shaft extension extends from the distal surface of the inlet body portion and engages with the outlet body portion.Docket: 292006-214015. The neonatal fluidic resuscitator device of any one of claims 8-14, wherein the plurality of fluid passage chambers further comprises a fluid passage chamber including a fluidic positive airway pressure (FPAP) channel.

16. The neonatal fluidic resuscitator device of claim 15, wherein the FPAP channel comprises a passage inlet, a passage outlet, and a passage exhaust, wherein selective alignment of FPAP channel substantially aligns the passage inlet with the inlet channel and the passage outlet with the outlet channel.

17. The neonatal fluidic resuscitator device of claim 16, wherein the FPAP channel comprises a fluid expansion zone disposed between the passage inlet and a nozzle configured to direct fluid flow into a central passage in fluid communication with the passage exhaust and the passage outlet.

18. The neonatal fluidic resuscitator device of any one of claims 8-17, comprising a safety channel in fluidic communication with the outlet port, the safety channel configured to provide emergency pressure relief and monitoring.

19. A method, comprising:selecting a first fluid passage chamber of a neonatal fluidic resuscitator device for use, the neonatal fluidic resuscitator device comprising:an inlet body portion comprising an inlet port and an inlet channel extending from the inlet port to a distal surface of the inlet body portion;an outlet body portion coupled to the inlet body, the outlet body portion comprising an outlet port and an outlet channel extending from a proximal surface of the outlet body portion to the outlet port; andthe rotatable cartridge disposed between the distal surface of the inlet body portion and proximal surface of the outlet body portion, the rotatable cartridgeDocket: 292006-2140comprising a plurality of fluid passage chambers configured to selectively align with the inlet channel and the outlet channel, the plurality of fluid passage chambers including a plurality of fluidic-powered ventilators configured to achieve a defined peak inspiratory pressure (PIP) for different neonate sizes;where the first fluid passage chamber is selected from the plurality of fluid passage chambers by rotating the rotatable cartridge to align the first fluid passage channel with the inlet channel and outlet channel; andinitiating fluid flow through the first fluid passage channel from a fluid source coupled to the inlet port.

20. The method of claim 19, wherein the fluid flow is supplied to a subject via a mask coupled to the outlet port.

21. The method of any one of claims 19 and 20, comprising rotating the rotatable cartridge to align a second fluid passage channel of the plurality of fluid passage channels with the inlet channel and outlet channel, thereby terminating fluid flow through the first fluid passage channel and initiating fluid flow through the second fluid passage channel.

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