Cannula device for high flow therapy

A nasal cannula is described herein for respiratory therapy which includes a first gas supply tub with a distal end terminating in a first connector, and a nasal cannula body which includes a first end rotatably coupled to the first connector, a second end opposite the first end, a longitudinal axis extending from the first end to the second end, and a first nasal prong in fluid communication with the first gas supply tube. The first nasal prong is rotatable relative to the first gas supply tube about the longitudinal axis of the nasal cannula body.

BACKGROUND

Patients with respiratory ailments may be treated with respiratory assist devices, for example, devices that deliver supplemental breathing gas to a patient. Such devices may deliver gas to a patient using high flow therapy (“HFT”). HFT devices deliver a high flow rate of breathing gas to a patient via an interface such as a nasal cannula to increase a patient's fraction of inspired oxygen (FiO2), decrease a patient's work of breathing, or to do both. Nasal cannulae are commonly used in acute short-term therapy and in therapy for chronic issues.

Nasal cannulae generally have a single geometry for the insertion angle of the nasal prongs into a patient's nares. However, amongst a population of patients there is variability in the anatomy of the nares, nasal cavity and facial structures surrounding the nares. Furthermore, nasal cannulae often provide only one directional mode and can be difficult to affix on a patient in alternative orientations. As a result, in some patients, the nasal prongs of a nasal cannula abut sensitive tissues within the nasal cavity and the stream of breathing gas is directed into the tissues rather than into the nasal passageways, diminishing the effects of treatment and causing irritation of sensitive tissues or structures and mucous membranes. Improper positioning of nasal prongs within the nares of a patient can result in inadequate upper airway flush and reduce effectiveness of respiratory therapies. To fit nasal prongs to a patient, sometimes nasal cannula prongs are cut with a scissors in medical environments to change the size, length, and/or angle of the prongs, but this often leaves the prongs with sharp edges that can further irritate or damage sensitive tissues within the nasal cavity. Furthermore, nasal cannulae used for respiratory therapies may need to be removed in order to clean secretions around a nare, unblock an occluded nare or administer other medical therapies which require access to a patient's nare. Removal of the nasal cannula prongs from the nare stops the respiratory therapy.

Using current methods of restraining and orienting gas supply tubing for use with nasal cannulae, patient movement and adjustments to the gas supply tubes can cause rubbing and skin irritation and can lead to misalignment or poor orientation of the nasal prongs within the nares. In some instances, movement of a gas supply tube can cause jostling of the nasal cannula leading to the nasal prongs being poorly oriented in the nares and causing irritation and loss of efficiency of respiratory therapy. In other instances, movement of the nasal cannula, for example, due to a patient talking, eating or otherwise moving, causes motion of the gas supply tubes which may rub on or around the patient's ears also causing irritation and potential damage. In many instances, and in particular for pediatric patients and neonates receiving respiratory therapies, patients depend on the respiratory therapy to maintain proper oxygen and ventilation status. Therapy is often effective as long as the nasal prongs remain properly positioned within the nares. Methods of affixing gas supply tubes to maintain a proper orientation of the prongs, including medical tape and polymeric wound adhesives, are often difficult to remove or replace, inadequately affix the tubing and cause irritation or damage to a patient's skin.

Trauma from the nasal cannula can occur during long-term therapies (e.g., periods greater than seven days of continuous use) and may include the development of medical device-related pressure ulcers (MDRPU). The gas supply tubing may be pliable and soft when not pressurized, but may become distended under internal pressure and warm due to the passage of heated gas through the tubing. The rubbing of the hard tubing around the ears may lead to vascular compression of the dermal capillary bed as well as abrasive surface trauma. The warmth of the tubing may cause sweating and exacerbate the irritation and skin breakdown. If worn too tightly, over long periods, the supply tubing can cause undue pressure and friction about the ears and at other points of contact with a patient's skin. In some cases, rubbing of the supply tubing over the ear may lead to the development of pressure ulcers in the posterior ear and temporomastoid area behind the ear and along the path of the nasal cannula gas supply tubing.

SUMMARY

Accordingly, disclosed herein are systems, methods, and devices providing enhanced patient comfort in systems relating to nasal cannulae for respiratory therapy. For example, a nasal cannula with rotatably adjustable prongs is described below that allows a patient or health care professional to rotate the prong to ensure heated and humidified breathing gas is directed from the outlet of the nasal prong and into the nasal passageway rather than into the mucosa. Rotatable prongs also allow a health care professional to rotate one or both prongs out of the nare to rest the nare, clean secretions around the nare and/or access the nare for an alternate purpose. In particular, for infant nasal cannulae, the ability to rotate one or both prongs out of the nares allows a health care professional to insert a feeding tube into one of the nares while continuing respiratory therapy at the other nare.

Additionally or alternatively, a nasal cannula with a stable orientation below the nares, which simultaneously allows rotational relief of the prongs within the nares, allows the nasal cannula to be fit to the anatomies of a variety of patients and increases the comfort of patients in both short and long-term therapies. A nasal cannula assembly with the capability of rotational nasal prong adjustment in the nares prevents tissue irritation and abrasion of nasal passageways caused by direct contact of the nasal prong against sensitive tissues in the nare and nasal cavity. The rotational adjustment of the prongs also directs gas flow into the nasal passageway and away from sensitive tissue.

In another example, nasal cannulae with adjustable distance between the nasal prongs are described. The adjustable distance between the prongs allows the nasal cannula to be fit to a variety of patient sizes and anatomies with minimal irritation to sensitive tissues in the nasal passage. Furthermore, adjustment of the distance between prongs allows a health care professional to position the prongs in the center of the nare to optimize the flow of breathing gas into the nasal passageway for optimal upper airway flush.

In another example, a variety of fastening mechanisms for affixing gas supply tubes and a nasal cannula on a patient are described. A swivel connector that does not transfer torque from the gas supply tubes to the nasal cannula is described. A tubing guide is described, which affixes a gas supply tube to a patient's skin with a removable adhesive pad. The tubing guide is configured such that the gas supply tube may be removed from the tubing guide and the gas supply tube will have the proper orientation upon replacement. A slidable connector is described for retaining two gas supply tubes below a patient's chin without kinking.

Various strap systems are also described, which hold the nasal cannula in a proper position on a patient's face to ensure efficient delivery of respiratory therapy into the patient's nares. Simultaneously, the strap systems prevent chafing, irritation, and ulceration of the sensitive skin on and around the ears by holding the gas supply tubes away from the ears or otherwise protecting the ears. Gas supply tubes become hard when they are pressurized by the passage of breathing gas through them, and may be warm, causing sweating and leading to faster breakdown of the skin where the tubes rub against bony protrusions around the ears. Preventing the rubbing of gas supply tubes against the ears increases patient comfort and decreases risk of developing an MDRPU, while ensuring that the nasal cannula is secured to the patient for delivery of respiratory therapy.

In one aspect, a nasal cannula for respiratory therapy includes a first gas supply tube with a distal end terminating in a first connector, and a nasal cannula body that includes a first end rotatably coupled to the first connector, a second end opposite the first end, a longitudinal axis extending from the first end to the second end, and a first nasal prong in fluid communication with the first gas supply tube. The first nasal prong is rotatable relative to the first gas supply tube about the longitudinal axis of the nasal cannula body.

The means for the rotatable coupling may vary. For example, in some implementations, the rotatable coupling between the first end of the nasal cannula body and the first connector is a bearing. In some implementations, the rotatable coupling between the first end of the nasal cannula body and the first connector is a journal bearing. Furthermore, the journal bearing may provide varying amounts of static frictional torque. For example, in some implementations, the journal bearing has sufficient static frictional torque to maintain a rotational position of the first nasal prong relative to the first gas supply tube. In some implementations, the journal bearing has a frictional torque of about 0.1 Nm to 1 Nm. Additionally or alternatively, in some implementations, the journal bearing has an internal surface contoured such that the journal bearing has intermittent rotational stops. Additionally or alternatively, in some implementations, the nasal cannula also includes a lock configured to lock a rotational position of the first nasal prong relative to the first gas supply tube.

The number of nasal prongs extending from the nasal cannula may vary. For example, in some implementations, the nasal cannula body may include a second nasal prong, in addition to a first nasal prong. Furthermore, the second nasal prong may be rotatable. For example, in some implementations, the second nasal prong is rotatable relative to the first gas supply tube about the longitudinal axis of the nasal cannula body. In some implementations, the first prong is rotatable relative to the second nasal prong about the longitudinal axis of the nasal cannula body. Additionally or alternatively, the location and/or arrangement of the nasal prongs may vary. For example, in some implementations, the nasal cannula body includes a first section and a second section disposed adjacently along the longitudinal axis of the nasal cannula body, and the first nasal prong is disposed on the first section and the second nasal prong is disposed on the second section. In some implementations, the first section and the second section are coupled by a journal bearing, and the first section is rotatable about the longitudinal axis of the nasal cannula body relative to the second section.

The number and/or arrangement of gas supply tubes may vary. For example, in some implementations, the nasal cannula includes a second gas supply tube with a distal end that terminates in a second connector, and the second end of the nasal cannula body is rotatably coupled to the second connector. In some implementations, the second nasal prong is in fluid communication with the second gas supply tube. In other implementations, the first nasal prong is not in fluid communication with the second prong. In some implementations, the first nasal prong and the second nasal prong are joined by a solid bridge connector. Additionally or alternatively, in some implementations, the nasal cannula body is detachable from the first supply tube.

The arrangement of and/or distance between the nasal prongs may vary. In some implementations, the nasal cannula body includes a surface contoured to provide a discrete number of stable axial positions of the first nasal prong. Additionally or alternatively, in some implementations, an axial distance between the first nasal prong and the second nasal prong along the longitudinal axis of the nasal cannula body is adjustable. In some implementations, the first nasal prong is axially slidable along the longitudinal axis of the nasal cannula body relative to the second nasal prong.

The flow rate of the breathing gas in the nasal cannula may vary. In some implementations, the nasal cannula includes a gas source wherein the gas source is configured to provide breathing gas at a flow rate of over 8 liters per minute (LPM) (e.g., 10 LPM, 15 LPM, etc.). Additionally or alternatively, the nasal cannula may work with various components for delivering the breathing gas to the patient. For example, in some implementations, the first connector includes a first section sized to receive the first gas supply tube and a second section sized for insertion into the first end of the nasal cannula body. The first section is coupled to the second section at a bearing, and the second section is configured to swivel relative to the first section. Additionally or alternatively, in some implementations, the nasal cannula includes a slidable connector that has a body, a first opening sized to receive two supply tubes, a second opening sized to receive a single supply tube, a third opening sized to receive a single supply tube, and a wedge disposed between the second and third openings. The first gas supply tube passes through the first and second openings, and the second gas supply tube extends through the first and third openings. The second and third openings are offset such that the first and second gas supply tubes diverge in exiting the second and third openings. Additionally or alternatively, in some implementations, the nasal cannula has a tubing guide with a flexible body and a guide connector coupled to a first side of the flexible body. The guide connector has a first opening and a second opening opposite the first opening, each sized to receive a gas supply tube. The first gas supply tube passes through the first opening and the second opening, and the flexible body includes a second side coated in a biocompatible adhesive. In some implementations, the nasal cannula includes an elastomeric loop having a connector detachably coupled to a gas supply tube. The connector is coupled non-fluidically to the first gas supply tube, and the elastomeric loop is sized to hang over an ear.

In another aspect, a kit for a high flow therapy system includes a nasal cannula. The nasal cannula includes a nasal cannula body and a first gas supply tube that has a distal end terminating in a first connector. The nasal cannula body also includes a first end rotatably coupled to the first connector, a second end opposite the first end, a longitudinal axis extending from the first end to the second end, and a first nasal prong in fluid communication with the first gas supply. The first nasal prong is rotatable relative to the first gas supply tube about the longitudinal axis of the nasal cannula body.

The means for the rotatable coupling may vary. For example, in some implementations, the rotatable coupling between the first end of the nasal cannula body and the first connector is a bearing. In some implementations, the rotatable coupling between the first end of the nasal cannula body and the first connector is a journal bearing. The journal bearing may provide varying amounts of static frictional torque. For example, in some implementations, the journal bearing has sufficient static frictional torque to maintain a rotational position of the first nasal prong relative to the first gas supply tube. In certain implementations, the journal bearing has a frictional torque of about 0.1 Nm to 1 Nm. Additionally or alternatively, the journal bearing has an internal surface contoured such that the journal bearing has intermittent rotational stops.

A variety of fastening mechanisms may be provided with the kit or used with the kit to comfortably secure the nasal cannula and supply tubes on a patient. For example, in some implementations, the kit includes a fastening mechanism that is configured to secure the nasal cannula and the first gas supply tube on a patient during use. In some implementations, the fastening mechanism includes a fabric encasement sized to cover a length of the first gas supply tube that extends over a patient's ear. Additionally or alternatively, in some implementations, the fabric encasement includes a wire structure within the fabric disposed circumferentially around the length of the first gas supply tube that extends over a patient's ear. The wire structure is configured to hold the length of the first gas supply tube away from the patient's ear. The fabric comprising the fabric encasement may vary. For example, in some implementations, the fabric encasement is a wicking fabric and a low-friction fabric. In other implementations, the fabric encasement is a silicone encasement sized to cover a length of the first gas supply tube that extends over a patient's ear.

Additionally or alternatively, in some implementations, the fastening mechanism comprises a strap sized to extend around a backside of a patient's head. The strap has a first end and a second end, the first end of the strap coupled to the first gas supply tube above a first ear of the patient and the second end of the strap coupled to a second gas supply tube above a second ear of the patient. The first gas supply tube and the second gas supply tube are secured above the first ear and above the second ear. Additionally, or alternatively, in some implementations, the strap is coupled to the first gas supply tube by an adjustable securing mechanism at the first end of the strap. In some implementations, the first end of the strap comprises a raised section having a groove around the edge of the raised section sized to receive the first gas supply tube.

Additionally, or alternatively, in some implementations, the fastening mechanism includes a band configured to be coupled to the first gas supply tube above the first ear of the patient and to be coupled to the second gas supply tube above the second ear of the patient. The band is sized to extend over a top of the patient's head. In some implementations, the strap is coupled to the band.

Additionally or alternatively, in some implementations, the fastening mechanism comprises an elastomeric loop having a connector detachably coupled to the first gas supply tube. The connector is coupled non-fluidically to the first gas supply tube and the elastomeric loop is sized to hang over an ear. In some implementations, the elastomeric loop is configured to be coupled to the first gas supply tube at a coupler configured to be positioned at a bottom point of the elastomeric loop. Furthermore, the elastomeric loop may be covered to provide additional comfort or support to the ear. For example, in some implementations, the elastomeric loop includes a loop encasement covering the elastomeric loop and configured to be disposed between the ear loop and the patient's ear. In some implementations, the loop encasement includes a fluid-filled cushion or foam.

Additionally or alternatively, in some implementations, the fastening mechanism has a tubing guide with a flexible body and a guide connector coupled to a first side of the flexible body. The guide connector has a first opening and a second opening opposite the first opening, each sized to receive a gas supply tube. The first gas supply tube passes through the first opening and the second opening, and the flexible body includes a second side coated in a biocompatible adhesive. Additionally or alternatively, in some implementations, the first gas supply tube includes a first lumen configured to receive the breathing gas and a second lumen encompassing the first lumen configured to receive cooled gas. In some implementations, a second gas supply tube is coupled to the second end of the nasal cannula body.

Additionally or alternatively, the nasal cannula may work with various components for delivering the breathing gas to the patient. For example, in some implementations, the kit includes a slidable connector that has a body, a first opening sized to receive two supply tubes, a second opening sized to receive a single supply tube, a third opening sized to receive a single supply tube, and a wedge disposed between the second and third openings. The first gas supply passes through the first and second openings and the second gas supply tube extending through the first and third openings. The second and third openings are offset such that the first and second gas supply tubes diverge exiting the second and third openings. Additionally or alternatively, in some implementations, the first connector includes a first section sized to receive the first gas supply tube and a second section sized for insertion into the first end of the nasal cannula body. The first section is coupled to the second section at a bearing and the second section is configured to swivel relative to the first section. In some implementations, the connector is configured to allow the second section 360° of rotation relative to the first section. The flow rate of the breathing gas in the nasal cannula may vary. In some implementations, the kit includes a gas source configured to provide breathing gas at a flow rate of over 8 LPM (e.g., 10 LPM, 15 LPM, etc.). In other implementations, the gas source is configured to provide breathing gas at a flow rate of over 20 LPM (e.g., 22 LPM, 25 LPM, 27 LPM, etc.).

The disclosed features may be implemented, in any combination and subcombination (including multiple dependent combinations and subcombinations), with one or more other features described herein. The various features described or illustrated above, including any components thereof, may be combined or integrated in other systems. Moreover, certain features may be omitted or not implemented.

DETAILED DESCRIPTION

To provide an overall understanding of the systems, methods, and devices described herein, certain illustrative embodiments will be described. Although the embodiments and features described herein are specifically described for use in connection with a high flow therapy system, it will be understood that all the components and other features outlined below may be combined with one another in any suitable manner and may be adapted and applied to other types of respiratory therapy and respiratory therapy devices, including low flow oxygen therapy, continuous positive airway pressure therapy (CPAP), mechanical ventilation, oxygen masks, Venturi masks, and Tracheostomy masks. Furthermore, it should be noted that while certain embodiments are discussed herein within regards to increasing a patient's comfort through varying means (e.g., nasal cannula prong arrangement, fastening mechanism, etc.), these various embodiments may be used in various combinations to increase a patient's overall level of comfort during treatment.

The systems and devices described herein increase patient comfort during respiratory therapies by ensuring a good fit between the patient's anatomy and the nasal cannula prongs while protecting sensitive tissues from irritation. Devices that allow adjustment of prong orientation within the nares allow proper delivery of respiratory therapy into the nasal cavity and optimize flushing of the upper respiratory tract. Ill-fitting nasal prongs can irritate sensitive tissues within the nare and can direct breathing gas into these tissues and mucosa, causing discomfort as well as decreasing the efficacy of therapies. By allowing a user to adjust the orientation of the nasal prongs within the nares with rotatable prongs and/or adjustment of the distance between nasal prongs, the nasal prongs may be properly positioned to provide comfortable therapy to the patient.

Devices that affix the nasal cannula on the patient's face include fastening mechanisms that hold the gas supply tubes away from a patient's ears. Warm or pressurized gas supply tubes that are looped over the ears can cause irritation and ulceration of the sensitive tissues and bony protrusions about the ear. By securing the gas supply tubes away from the ears, the nasal cannula and gas supply tubes are secured in position on the patient's face without causing irritation to the ears. Devices that retain the gas supply tubes from interfering or irritating the patient also increase patient comfort and ensure that the nasal cannula remains properly positioned for delivery of respiratory therapy.

FIG. 1shows an illustrative nasal cannula100for respiratory therapy. Nasal cannula100includes nasal cannula body104, first end106, second end108, first gas supply tube102, first connector110, longitudinal axis112of nasal cannula body104, and first nasal prong114. First gas supply tube102is rotatably connected to first end106of nasal cannula body104at first connector110. First nasal prong114is in fluid communication with first gas supply tube102through first connector110and nasal cannula body104. First nasal prong114is rotatable in direction116around longitudinal axis112of nasal cannula body104relative to first gas supply tube102.

While first nasal prong114is shown as extending straight up from a surface of nasal cannula body104, first nasal prong114may be curved such that first nasal prong114extends into a nare of a patient when nasal cannula100is in use. First nasal prong114may be oriented on nasal cannula body104such that first nasal prong114extends into the right nare or the left nare of a patient. First nasal prong114on nasal cannula body104is rotatable relative to first gas supply tube102in direction116such that first nasal prong114can be rotated within the nare of a patient to achieve a comfortable fit. First nasal prong114can also be rotated out of the nare of a patient in order to rest the nare during or between therapy sessions, to allow a patient or health care professional to clean the nare or tissues surrounding the nare, or to administer additional therapies at the nare. Nasal cannula body104rotates at first connector110to allow the rotation of first nasal prong114with respect to first gas supply tube102. First nasal prong114is rotatably adjustable in either rotational direction about longitudinal axis112of nasal cannula body104, such that first nasal prong114can be adjusted inward or outward from the face by a user to allow reorientation of first nasal prong114. Reorientation of first nasal prong114may improve the flow of breathing gas within the nasal cavity and decrease irritation to sensitive tissues with more control over directionality of breathing gas flow.

First nasal prong114is rotatable with application of sufficient force to effect rotation. Without the application of a deliberate rotational force, first nasal prong114remains stationary in position with respect to first gas supply tube102. The requirement of a deliberate force for rotation of first nasal prong114prevents accidental rotational slippage that would alter the orientation of first nasal prong114in the nare and potentially diminish effectiveness of the therapy or increase the irritation of tissues if first nasal prong114is misaligned due to slipping. First connector110and nasal cannula body104may be coupled at a junction with adequate material friction to prevent slippage. First connector110may be coupled to nasal cannula body104by a bearing, which, for example, allows the nasal cannula body104to rotate freely about its longitudinal axis112. In some implementations, the coupling between first connector110and nasal cannula body104is a journal bearing. In some implementations, the journal bearing has sufficient static frictional torque to maintain the rotational position of first nasal prong114relative to first gas supply tube102. The journal bearing may have a frictional torque of about 0.1 Nm to 1 Nm. In some implementations, the journal bearing has a frictional torque of 0.05 Nm, 0.1 Nm, 0.2 Nm, 0.3 Nm, 0.4 Nm, 0.5 Nm, 0.6 Nm, 0.7 Nm, 0.8 Nm, 0.9 Nm, 1 Nm, 1.2 Nm, 1.5 Nm, 2 Nm, or any other suitable frictional torque. In some implementations, the coupling between first connector110and first nasal prong114has a surface with contours that allow a series of intermittent rotational stops such that the first nasal prong114can be rotated into discreet positions relative to first gas supply tube102. In some implementations, the coupling between first connector110and first nasal prong114is barbed. In other implementations, the coupling between first connector110and first nasal prong114is smooth to allow continuous rotational adjustment of first nasal prong114with respect to first gas supply tube102. In some implementations, nasal cannula body104may include a locking mechanism for locking of first nasal prong114in a rotational position relative to first gas supply tube102.

In some implementations, nasal cannula body104includes a patient-facing portion (i.e., a section of nasal cannula body104that is directly adjacent to a patient) that is fit to a patient anatomy. The patient-fitted portion of nasal cannula body104provides stability to the nasal cannula100while on the face of a patient. In some embodiments, the patient-fitted portion is a flattened section of plastic or other material fitted to the surface of a patient's face below the nares above the patient's upper lip and incorporating the philtrum. The additional stability of the nasal cannula body104increases patient comfort and prevents slippage of the nasal cannula body104during use.

In some implementations, first nasal prong114is removable from nasal cannula body104. In such implementations, first nasal prong114is manufactured in a variety of sizes, diameters, lengths or angles and can be chosen based on patient anatomy and placed on nasal cannula body104. A replaceable first nasal prong114allows the prong to be chosen to fit the patient and decreases irritation of nasal passages that occurs with ill-fitting or too big nasal prongs. In particular, when nasal cannula100is used with HFT systems, ill-fitting nasal prongs may direct heated breathing gas into the nasal tissue and cause irritation or pressure trauma to internal nasal tissues and mucosa during extended use. Rotatably adjustable and replaceable nasal prongs provide flexibility of use and increased patient comfort during use of nasal cannulae.

WhileFIG. 1shows a nasal cannula100having a single rotatable first nasal prong114,FIG. 2shows an illustrative nasal cannula200with two prongs and rotatable cannula body. Nasal cannula200includes nasal cannula body204with first end206and second end208, first nasal prong214, first outlet220, second nasal prong218, second outlet222, longitudinal axis212, first gas supply tube202, first connector210, second gas supply tube228, second connector230, position lock224, and rotational stop indicators226. First gas supply tube202is connected to first end206of nasal cannula body104at first connector210. Second gas supply tube228is connected to second end208of nasal cannula body204at second connector230. First nasal prong214and second nasal prong218are in fluid communication with first gas supply tube202and second gas supply tube228, such that a flow of breathing gas through first gas supply tube202or second gas supply tube228flows through nasal cannula body104and out through first outlet220and second outlet222. First nasal prong214and second nasal prong218are rotatable about longitudinal axis212of nasal cannula body204with respect to one or both of first gas supply tube202and second gas supply tube228. As inFIG. 1, though first nasal prong214and second nasal prong218are depicted as extending straight out from a surface of nasal cannula body204, first nasal prong214and second nasal prong218may be curved.

First nasal prong214and second nasal prong218rotate as a unit about longitudinal axis212of nasal cannula body204, allowing the position of first nasal prong214and second nasal prong218to be adjusted within the nares of a patient. The rotational adjustability of first nasal prong214and second nasal prong218allows a user to position first nasal prong214and second nasal prong218such that breathing gas flows through first gas supply tube202, second gas supply tube228, and nasal cannula body204to exit through first outlet220of first nasal prong214and second outlet222of second nasal prong218into the nasal passageway rather than toward sensitive tissues of the nare. The directional adjustment of the breathing gas flow by rotation of first nasal prong214and second nasal prong218increases efficiency of treatment and increases patient comfort by limiting irritation that can arise from poorly positioned prongs. In particular, during HFT sessions, nasal prongs that are directed toward a sensitive tissue or structure in the nasal cavity can cause pressure trauma to the tissue when heated and pressurized breathing gas is directed at these tissues.

Rotational adjustability of first nasal prong214and second nasal prong218further allows a user to remove first nasal prong214and second nasal prong218from the nares in order to clean or rest the nares or to deliver other therapies without removal of the nasal cannula body204from the patient's face. Restraining straps (not shown) for first gas supply tube202and second gas supply tube228that hold the nasal cannula200on a patient's face do not need to be removed to allow access to the nares.

First nasal prong214and second nasal prong218are rotatable about longitudinal axis212of nasal cannula body204with application of sufficient force to effect rotation, and first nasal prong214and second nasal prong218remain stationary with respect to first gas supply tube202and second gas supply tube228in the absence of deliberate rotational force. Thus, first nasal prong214and second nasal prong218do not slip from position during use. First connector210and second connector230may be coupled to first end206and second end208of nasal cannula body204, respectively, at a junction with adequate material friction to prevent slippage. First connector210and second connector230may be coupled to nasal cannula body204by bearings. In some implementations, the coupling between first connector210and nasal cannula body204, and between second connector230and nasal cannula body204is a journal bearing. In some implementations, the journal bearing has a frictional torque of about 0.1 Nm to 1 Nm. In some implementations, the journal bearing has a frictional torque of 0.05 Nm, 0.1 Nm, 0.2 Nm, 0.3 Nm, 0.4 Nm, 0.5 Nm, 0.6 Nm, 0.7 Nm, 0.8 Nm, 0.9 Nm, 1 Nm, 1.2 Nm, 1.5 Nm, 2 Nm, or any other suitable frictional torque. In some implementations, one or both of first connector210and second connector230includes position lock224to lock the first nasal prong214and second nasal prong218in a rotational position relative to first gas supply tube202and second gas supply tube228. In some implementations, one or both of first connector210and second connector230include contours that allow first nasal prong214and second nasal prong218to rotate to discreet intermittent rotational positions. In some implementations, one or both of first connector210and second connector230have smooth surfaces to allow a continuous rotation of first nasal prong214and second nasal prong218about longitudinal axis212of nasal cannula body204with respect to first gas supply tube202and second gas supply tube228.

While nasal cannula200shows a nasal cannula having a first nasal prong and a second nasal prong, in some embodiments nasal cannula200may include a third nasal prong for delivery of aerosolized medicament or other treatment. Third nasal prong (not shown) may be positioned in or on either of first nasal prong214or second nasal prong218. In some implementations, first nasal prong214and second nasal prong218are in fluid communication with first gas supply tube202and first gas supply tube202supplies heated and humidified breathing gas to first outlet220and second outlet222for administration of HFT, while third nasal prong is in fluid communication with second gas supply tube228, which supplies aerosolized medicament to a third outlet on third nasal prong. In such implementations, third nasal prong is rotatable with first nasal prong214and second nasal prong218about longitudinal axis212of nasal cannula body204.

Nasal cannula200ofFIG. 2has two nasal prongs that rotate as a unit about a longitudinal axis of the nasal cannula body. In some implementations, however, a first nasal prong may be rotatable about a longitudinal axis relative to a position of a second nasal prong.FIG. 3shows an illustrative nasal cannula300with a first section334of a nasal cannula body304rotatable with respect to a second section336. Nasal cannula300includes first gas supply tube302, first connector310, second gas supply tube328, second connector330, nasal cannula body304having first end306, second end308, first section334, second section336, and longitudinal axis312, first nasal prong314, first outlet320, second nasal prong318, second outlet322, separating wall332, and cannula bearing338. Nasal cannula body304is divided into first section334, including first nasal prong314in fluid communication with first gas supply tube302, and second section336, including second nasal prong318in fluid communication with second gas supply tube328. First gas supply tube302is coupled to first end306of nasal cannula body304at first connector310. Second gas supply tube328is coupled to second end308of nasal cannula body304at second connector330. First nasal prong314and second nasal prong318are rotatable in direction316about longitudinal axis312of nasal cannula body304with respect to one or both of first gas supply tube302and second gas supply tube328.

First section334, including first nasal prong314, is rotatable about longitudinal axis312with respect to a position of second section336, including second nasal prong318. In some implementations, first nasal prong314and second nasal prong318are in fluid communication with each other. First section334and second section336are joined at cannula bearing338, allowing independent rotation of first nasal prong314on first section334and second nasal prong318on second section336. Cannula bearing338may be a journal bearing. Independent rotational adjustment of first nasal prong314and second nasal prong318allows a user to independently position first nasal prong314and second nasal prong318within the nares of a patient to account for non-symmetrical anatomy of the nasal cavity and structures. Additionally, independent rotational adjustment of first nasal prong314and second nasal prong318allows a user to rotate first nasal prong314out of the nare while leaving second nasal prong318directed into the nare so that therapy can continue at one nare while the other nare is rested or cleaned or while additional therapies are administered at the other nare.

In some implementations, first section334and second section336are not in fluid communication, but rather are divided by separating wall332. In such implementations, first section334and second section336are rotatable relative to each other and relative to a position of one or both of first gas supply tube302and second gas supply tube328. Fluid separation of first section334and second section336allows for administration of different therapies through the first nasal prong314and second nasal prong318. Furthermore, the fluid separation of first section334and second section336may decrease noise associated with the administration of breathing gas through the nasal cannula300. Manufacture of first section334and second section336as separate pieces, which are joined at a separating wall332, does not require additional seals about the rotatable connection between first section334and second section336.

FIG. 4shows an illustrative cross-sectional view of a nasal cannula, such as nasal cannula100,200or300shown inFIG. 1, 2 or 3having a rotatable nasal prong. The cross-sectional view of the nasal cannula inFIG. 4shows nasal cannula body404, first nasal prong414situated in patient nare448. First nasal prong414is rotatable in direction416about longitudinal axis412, which may correspond to longitudinal axis112, of nasal cannula body404, such that first nasal prong414has a first position of first nasal prong414ahaving a high entry angle into patient nare448and can be rotated into second position of first nasal prong414bhaving a shallow entry angle into patient nare448. Rotational adjustment of first nasal prong414allows the position of first nasal prong414to be adjusted to fit the nasal cavity anatomy of a patient. In some implementations, first nasal prong414is rotated about longitudinal axis in a smooth continuous adjustment. In other implementations, first nasal prong414is rotated into discreet positions dictated by contours within a coupling in nasal cannula body404.

In some implementations, a nasal cannula body includes a rotating portion on which nasal prongs are located and a non-rotating portion.FIG. 5shows an illustrative nasal cannula500with rotatable nasal prongs and a solid bridge542of the nasal cannula body504. Nasal cannula500includes nasal cannula body504, first end506, second end508, first open end546, second open end544, longitudinal axis512, first gas supply tube502, second gas supply tube528, first nasal prong514, first outlet520, second nasal prong518, second outlet522, and rotating prong element537. Nasal cannula body504includes first end506in fluid connection with first open end546and second end508in fluid communication with second open end544. First end506and second end508of nasal cannula body504are coupled by solid bridge542through which there is no gas flow. Solid bridge542may include a patient-facing stabilizing surface that prevents movement of nasal cannula500once it is affixed to a patient's face. Rotating prong element537includes first nasal prong514and second nasal prong518, and is configured to be inserted into first open end546and second open end544of nasal cannula body504. Rotating prong element537is rotatable in direction516about longitudinal axis512with respect to a position of nasal cannula body504. In some implementations, first end506and second end508of nasal cannula body504are in fluid communication when rotating prong element537is inserted into nasal cannula body504. In some implementations, rotating prong element537is removable from nasal cannula body504.

Rotational adjustment of first nasal prong514and second nasal prong518on rotating prong element537inserted into nasal cannula body504allows for adjustment of nasal prong positioning within the nare of a patient while maintaining a stable connection with the patient's face via solid bridge542of nasal cannula body504. Nasal cannula body504does not slip or move while first nasal prong514and second nasal prong518are rotated on rotating prong element537to position in the nares or to remove from the nares for cleaning or resting of the nares or for administration of other therapies. The ability to adjust the position of first nasal prong514and second nasal prong518in a patient's nares without moving the nasal cannula body504improves patient comfort by allowing control of breathing gas directionality to protect sensitive tissues. Further, nasal prongs that are adjusted to fit the patient minimizes the need for multiple readjustments of the nasal cannula500or first gas supply tube502and second gas supply tube528during treatment. Movement of gas supply tubes can cause irritation about the ears, and repetitive adjustments during administration of therapies can lead to patient discomfort and development of pressure ulcers. A rotating first nasal prong514and second nasal prong518on rotating prong element537while solid bridge542remains in contact with a patient's face for stability decreases the need for readjustment of supply tubes.

In some implementations, nasal cannula500is constructed as a quiet nasal cannula in that first nasal prong514is in fluid communication with first gas supply tube502through first end506of nasal cannula body504and first open end546, but first nasal prong514is not in fluid communication with second nasal prong518. In such implementations, first nasal prong514and second nasal prong518are connected at a separating wall (such as separating wall332inFIG. 3), which may be configured as a solid bridge542between first nasal prong514and second nasal prong518. The separation of breathing gas flow from first gas supply tube502through first outlet520from the breathing gas flow from second gas supply tube528through second outlet522minimizes noise at the nasal cannula body504proximal to the patient, because breathing gas flows do not meet between first nasal prong514and second nasal prong518as when the two prongs are in fluid communication.

While nasal cannula100,200,300, and500inFIGS. 1, 2, 3, and 5include rotationally adjustable prongs, in some implementations the distance between prongs can be adjusted.FIG. 6shows a top view of an illustrative nasal cannula600allowing adjustment of the distance between prongs. The mechanism for enabling the adjustment may vary. One mechanism for allowing such adjustment is shown inFIG. 6. Nasal cannula600includes first nasal prong614, second nasal prong618, first prong assembly621, second prong assembly623, first finger tab631, second finger tab633, locking teeth656and lock658. First prong assembly621includes first nasal prong614and first outlet620. Second prong assembly623includes second nasal prong618, second outlet622, and an extension comprising locking teeth656. First prong assembly621engages with second prong assembly623by accepting the extension, including locking teeth656, of second prong assembly623into an internal track of first prong assembly621. In some implementations, the internal track of first prong assembly621also includes teeth indents to interact with locking teeth656and hold first prong assembly621and second prong assembly623in place. First prong assembly621and second prong assembly623are held in a position by locking teeth656of second prong assembly623and lock658positioned on first prong assembly621. The extension comprising locking teeth656is toward a patient, and the backside of locking teeth656forms a solid face that provides stability against the patient's anatomy beneath the nares. The distance d between first nasal prong614and second nasal prong618can be changed by pushing first prong assembly621and second prong assembly623toward each other using first finger tab631and second finger tab633or by pulling apart.

Nasal cannula600can be manufactured in three pieces, comprising first prong assembly621, second prong assembly623and lock658. Distance d between first nasal prong614and second nasal prong618can be repeatedly adjusted and distance d is easy to adjust by pulling or pushing on first finger tab631and second finger tab633on a non-patient facing side of nasal cannula600. Precise adjustment of distance d between first nasal prong614and second nasal prong618is possible, allowing for precise placement of first nasal prong614and second nasal prong618within the nares of a patient for optimal efficiency of treatment and minimal irritation caused by ill-fitting or misaligned prongs.

As shown inFIG. 6(andFIG. 8below) nasal cannulas described herein may allow for adjustable distances between prongs. In some implementations, distance between nasal prongs may be adjustable and nasal prongs may also be rotationally adjustable.FIG. 7shows a nasal cannula700allowing adjustment of the distance between nasal prongs as well as rotation of nasal prongs. Nasal cannula700includes nasal cannula body704, consisting of first cannula assembly711and second cannula assembly713, first prong assembly721, second prong assembly723, first nasal prong714, first outlet720, second nasal prong718, second outlet722, first finger tab731, second finger tab733, locking teeth756, lock758, first gas supply tube702, first connector710, second gas supply tube728and second connector730. Nasal cannula body704comprises a first end706including first cannula assembly711and first finger tab731, and a second end708, including second cannula assembly713, second finger tab733and an extension including locking teeth756. First cannula assembly711includes a bridge742with a hollow passage inside configured to accept the extension of second cannula assembly713, including locking teeth756. The hollow passage (not shown) may include notches that interact with locking teeth756to hold first cannula assembly711and second cannula assembly713in position. Locking teeth756slide in the hollow passage of bridge742to allow first cannula assembly711and second cannula assembly713to move relative to each other in an axial direction760parallel to longitudinal axis712, changing distance d between first nasal prong714on first cannula assembly711and second nasal prong718on second cannula assembly713. Lock758on second cannula assembly713locks the position of first cannula assembly711relative to second cannula assembly713. First gas supply tube702is coupled to first end706of first cannula assembly711at first connector710and is also coupled to first prong assembly721. Second gas supply tube728is coupled to second end708of second cannula assembly713at second connector730and is also coupled to second prong assembly723.

First prong assembly721is configured to allow rotation in a direction716about longitudinal axis712. First prong assembly721may be coupled to first connector710by a bearing, such as a journal bearing allowing continuous or ratcheted rotation. Second prong assembly723is configured to allow rotation in direction716about longitudinal axis712. Second prong assembly723may be coupled to second connector730by a bearing that may be a journal bearing allowing either continuous or intermittent rotation as well. Simultaneous control over rotational adjustment and the distance between first nasal prong714and second nasal prong818allows a user to precisely adjust the fit of nasal cannula700to a particular patient. Precise fitting of the nasal prongs to a patient reduces irritation due to nasal prongs contacting surfaces and tissues within the nares and increases the efficiency of respiratory therapy by directing the flow of breathing gas into the nasal passageway for optimal flushing of the upper respiratory tract. Furthermore, nasal cannula700includes first nasal prong714and second nasal prong718that are not in fluid communication, decreasing the noise associated with breathing gas flows meeting proximal to the patient.

FIG. 8shows an alternate illustrative nasal cannula800allowing adjustment of the distance between nasal prongs and rotation of nasal prongs. Nasal cannula800includes nasal cannula body804, first end806, second end808, first gas supply tube802, first connector810, second gas supply tube828, second connector830, longitudinal axis812, first nasal prong814, first outlet820, second nasal prong818, second outlet822, sliding panel852, and slide track854. Nasal cannula body804is connected at first end806to first gas supply tube802by first connector810. Second end808of nasal cannula body804is coupled to second gas supply tube828by second connector830. Nasal cannula body804includes first nasal prong814and second nasal prong818, separated by distance d. Nasal cannula body804also includes slide track854configured as a cutout in an outer surface of nasal cannula body804. First nasal prong814is positioned on sliding panel852, which slides in slide track854in axial direction850parallel to longitudinal axis812such that the distance d between first nasal prong814and second nasal prong818is changeable. For example, first nasal prong814aon sliding panel852with distance d1from second nasal prong818can be moved in axial direction850to the position of overlaid first nasal prong814bhaving distance d2from second nasal prong818. The ability to change the distance d between the first nasal prong814and second nasal prong818allows the nasal cannula800to be fit to the anatomy of patient's of various sizes, increasing patient comfort.

In some implementations, the coupling between the first connector810and the first end806of the nasal cannula body804, and the second connector830and the second end808of the nasal cannula body804allow the nasal cannula body804to rotate in direction816about longitudinal axis812with respect to the first gas supply tube802and second gas supply tube828respectively. This allows the distance between the prongs to be adjusted, as well as rotational adjustments of the position of the prongs within the nare, permitting optimization of the prong orientation in the nares of a patient. As a result, airway flush may be optimized and irritation due to nasal prongs or breathing gas contacting the sensitive tissues in the nare can be lessened.

FIG. 9shows an illustrative swivel connector901for coupling a first gas supply tube902to a nasal cannula body904. Swivel connector901includes first portion966and second portion968, bearing967, opening972, and first gas supply tube902. Nasal cannula body904includes first end906, second end908, first nasal prong914, nozzle opening972, and adapter970. First portion966of swivel connector901is sized to receive first gas supply tube902. Second portion968of swivel connector901is coupled to first portion966by bearing967, which allows second portion968to rotate within first portion966. Second portion968is able to rotate radially in a radial direction962and able to swivel in swivel direction964. Second portion968engages with adapter970and first gas supply tube902is in fluid communication with nozzle opening972through first portion966and second portion968of swivel connector901and through nasal cannula body904.

The rotational and swivel motions of second portion968within first portion966allow nasal cannula body904to accommodate movement and torque on the first gas supply tube902with minimal motion of nasal cannula body. In some implementations, second portion968is capable of 360 degree, bidirectional motion. In some implementations, the allowed movement of second portion968describes a hemisphere. In some implementations, bearing967is incorporated into nasal cannula body904rather than on first gas supply tube902side. Movement of first gas supply tube902between the patient and the breathing gas supply is accommodated by the swivel movement of second portion968on bearing967such that nasal cannula body904is not jostled by movement of first gas supply tube902. Likewise, movement of nasal cannula body904due to a patient talking, moving or eating, for example, does not translate to motion of first gas supply tube902. Minimization of movement of first gas supply tube902decreases the occurrence of patient injury and irritation due to rubbing of the first gas supply tube902on patient skin. In particular, when first gas supply tube902is used for delivery of heated and humidified breathing gas for HFT, minimization of rubbing is critical to patient comfort as heated and pressurized supply tubes may cause pressure ulcers where they rub on a patient's skin.

FIG. 10shows an illustrative tubing guide fastener1075for use with first gas supply tube1002of a nasal cannula body1004.FIG. 11shows a cross-sectional view of tubing guide fastener1075. Tubing guide includes flexible body1076, guide connector1078, slit1080, first end opening1082, second end opening1084, and adhesive bottom1077. Flexible body1076is configured to be flat with adhesive bottom1077on a patient-facing side. Guide connector1078is configured as a circular or tube-shaped feature positioned across flexible body1076with slit1080running from first end opening1082to second end opening1084of guide connector1078permitting introduction of first gas supply tube1002. Guide connector1078is sized to accept first gas supply tube1002, which can be pressed through slit1080into guide connector1078where first gas supply tube1002is held in position. Flow of breathing gas through first gas supply tube1002is not impaired by guide connector1078, and gas supply tube is in fluid communication with nasal cannula body1004. Adhesive bottom1077is configured to releasably adhere to skin of a patient.

Tubing guide fastener1075is configured to hold a first gas supply tube1002in a position on a patient, for example, on a patient's cheek, to ensure that first nasal prong1014remains in an optimized position within nare1048. In some implementations, two tubing guide fasteners1075may be used to affix gas supply tubes to each of a patient's cheek. In some implementations, guide connector1078may be sized for small-bore tubing (e.g., NG tubing, IV tubing, umbilical catheters) or wide-bore patient tubing. In some implementations, guide connector1078runs straight across flexible body1076. In other implementations, guide connector1078is curved across the surface of flexible body1076. In some implementations, guide connector1078forms almost a complete circular cross-section. In some implementations, guide connector1078is sticky on an interior surface or otherwise grips first gas supply tube1002to avoid inadvertent movement of first gas supply tube1002. In other implementations, guide connector1078is able to slide along and/or rotate around first gas supply tube1002.

In some implementations, flexible body1076may be constructed from a single piece of plastic or silicone. In some implementations, adhesive bottom1077comprises a small hydrogel hydro-colloidal adhesive. Adhesive bottom1077is biocompatible and removable with minimal irritation or residue. In some implementations, tubing guide fastener1075is configured for use on a patient's cheek, nose or any other facial geometry. Tubing guide fastener1075not only provides a mechanism for affixation of first gas supply tube1002to the skin, but also allows a user to orient first gas supply tube for optimal placement of first nasal prong1014in nare1048. Slit1080permits introduction and removal of first gas supply tube1002, and, upon reintroduction of first gas supply tube1002to slit1080in guide connector1078, first gas supply tube1002is immediately returned to proper orientation. Tubing guide fastener1075may be used with any respiratory therapy. Tubing guide fastener1075may be particularly useful for retaining gas supply tubing used for delivery of HFT, because correct positioning of nasal prongs in the nares is important to provide optimum flushing of the upper respiratory tract.

FIG. 12shows an illustrative view of a slidable connector1285for use with gas supply tubing of a nasal cannula. Slidable connector1285includes body1286, first opening1288, second opening1290, third opening1292, and wedge1294. First opening1288is sized to receive first gas supply tube1202and second gas supply tube1228. Second opening1290is sized to receive first gas supply tube1202. Third opening1292is sized to receive second gas supply tube. A passageway is formed through body1286from first opening1288to second opening1290in which first gas supply tube1202passes. A passageway is formed through body1286from first opening1288to third opening1292through which second gas supply tube1228passes. Second opening1290and third opening1292are separated by wedge1294. First gas supply tube1214and second gas supply tube1218diverge about wedge1294. Wedge1294dictates angle1296at which first gas supply tube1202and second gas supply tube1228exit from body1286.

Slidable connector1285retains first gas supply tube1202and second gas supply tube1228and is slidable along first gas supply tube1202and second gas supply tube1228in order to temporarily shorten or lengthen a look of gas supply tubing around a patient's ears for securing the nasal cannula to the patient's face. The angle1296at which first gas supply tube1202and second gas supply tube1228exit slidable connector1285prevents kinking of first gas supply tube1202and second gas supply tube1228at the edge of body1286. Because kinking is prevented, outflow of gas to the patient through first gas supply tube1202and second gas supply tube1228is continuous and is not interrupted. Kinking changes the flow characteristic of the gas and can increase noise level in the outflow of gas as it exits the nasal prong. In some implementations, slidable connector1285includes guide paths for first gas supply tube1202and second gas supply tube1228. In other implementations, it is not necessary to include guide paths within body1286.

In some implementations, the interior of slidable connector1285serves to grip an exterior of first gas supply tube1202and second gas supply tube1228to maintain persistent sizing of the slidable connector1285without slippage such that first gas supply tube1202and second gas supply tube1228are held in position in slidable connector1285until a force is applied to slidable connector1285to move slidable connector1285along first gas supply tube1202and second gas supply tube1228. In some implementations, first gas supply tube1202and second gas supply tube1228are parallel to each other at first opening1288and are guided in curved paths away from each other to second opening1290and third opening1292, respectively. The curved path prevents the skin from being wedged between the tubing and the slidable connector1285. In some implementations, an end of body1286moves toward wedge1294which is patient-facing includes a material to improve comfort or reduce slippage on the skin. For example, the end of body1286may be formed of plastic or may be cushioned. A cushioned end of body1286may serve to protect skin of a patient from rubbing on heated and pressurized tubing during administration of HFT and may prevent irritation, as well as kinking of first gas supply tube1202and second gas supply tube1228. In some implementations, an end of body1286moves toward wedge1294which is patient-facing includes a stand-off portion (not shown) which is raised to contact a chin of the patient to further decrease occurrence of kinking of first gas supply tube1202and second gas supply tube1228for continuous delivery of breathing gas.

FIG. 13shows an illustrative view of a fastening mechanism1303for use with first gas supply tube1302of a nasal cannula having first over ear connector1397and second over ear connector1398to decrease the incidence of pain associated with gas supply tubing around the ears.FIG. 14shows a side-view of the fastening mechanism1303. Fastening mechanism1303includes first gas supply tube1302, second gas supply tube1328, nasal cannula body1304, first over ear connector1397, second over ear connector1398, first tube sliding connector1395and second tube sliding connector1399. First gas supply tube1302and second gas supply tube1328are fluidically coupled to nasal cannula body1304to provide breathing gas to first nasal prong1314and second nasal prong1318. First gas supply tube1302and second gas supply tube1328are affixed to the patient's face by first over ear connector1397and second over ear connector1398, respectively. First gas supply tube1302is connected to first over ear connector1397at first tube sliding connector1395and second tube sliding connector1399at a bottom of first ear1391. First over ear connector1397is configured to be placed over a first ear1391of a patient and is affixed to first gas supply tube1302at first tube sliding connector1395and second tube sliding connector1399such that first gas supply tube1302is suspended from first over ear connector1397looped over first ear1391. First tube sliding connector1395and second tube sliding connector1399are configured to be slidable over first gas supply tube1302to adjust the orientation of first gas supply tube1302. In some implementations, first tube sliding connector1395and second tube sliding connector1399are configured as friction fit barrels which allow a length to be adjusted by pulling an end of first over ear connector1397through second tube sliding connector1399. A length of first over ear connector1397can be adjusted multiple times using second tube sliding connector1399, and fastening mechanism1303can be precisely fit to a facial geometry such that first nasal prong1314and second nasal prong1318are properly positioned on a patient's face. In some implementations, first over ear connector1397is elastomeric.

First over ear connector1397and second over ear connector1398serve to affix nasal cannula body1304and first gas supply tube1302and second gas supply tube1328to a patient's face without first gas supply tube1302and second gas supply tube1328contacting the ears. Suspending first gas supply tube1302and second gas supply tube1328from the ears without allowing first gas supply tube1302and second gas supply tube1328to touch the sensitive skin around the ears serves to affix nasal cannula body1304to the face without irritating the skin around the ears with hot and pressurized tubing. The shorter path length which breathing gas, and, in particular, heated and humidified breathing gas for HFT, must travel through first gas supply tube1302prevents condensation of the gas in the supply tube known as “rainout.” Furthermore, the over the ear suspension of fastening mechanism1303allows a patient to eat or drink unencumbered while wearing nasal cannula body1304and fastening mechanism1303. In some implementations, a fabric encasement covers a portion of first over ear connector1397at the top of first ear1391to further protect the skin around the ear from irritation from the tubing. The fabric encasement may be a wicking fabric or a low-friction fabric. In some implementations, a wire structure surrounds all or a portion of first over ear connector1397at the top of first ear1391to hold first over ear connector1397further away from first ear1391. In some implementations, the wire structure instead comprises a skeleton of pliable plastic plates or a foam cushion layer. The wire structure may be encased within the fabric encasement. In other implementations, the fabric encasement may be comprised of silicone to reduce movement of first over ear connector1397on the skin. In some implementations, the silicone encasement comprises a silicone sheet which curls around first over ear connector1397. The silicone encasement may comprise two silicone sheets joined by silicone adhesive which can be used to label first over ear connector1397or may be used to encase first gas supply tube1302to provide a more comfortable surface where the skin and first gas supply tube1302meet. Fastening mechanism1303may be used on its own with any respiratory therapy that requires affixation of gas supply tubes to a patient's face. Fastening mechanism1303may be used with other features for retaining gas supply tubes, such as with slidable connector1385. Fastening mechanism1303may be used with HFT systems to prevent irritation to skin caused by rubbing of wide-bore gas supply tubes on and around the ears by suspending the gas supply tubes below the ears with over ear loops.

In some implementations, first over ear connector1397and second over ear connector1398are configured for use with small-bore gas supply tubing. In other implementations, first over ear connector1397and second over ear connector1398are configured for use with wide-bore gas supply tubing. In some implementations, first gas supply tube1302is a dual-lumen supply tube. In some implementations, first gas supply tube1302comprises a first lumen through which breathing gas passes, and a second lumen surrounding the first lumen through which cooled gas passes. In some implementations, the second lumen has micro-pores allowing the cooled gas to flow out of the second lumen to create an air buffer of cooled gas between a patient's skin and the gas supply tube. In some implementations, the cannula is also constructed to have a separate flow path about the outside of the cannula through which cooled gas passes, the separate flow path including micro-pores through which the cooled gas flows towards the patient's skin. The air buffer created between the tubing and/or cannula and the patient's skin lessens the pressure exerted by the tubing on the skin and decreases rubbing on the skin leading to less skin breakdown.

WhileFIGS. 13 and 14show a fastening mechanism1303making use of over ear connectors which support gas supply tubes hanging below the ears,FIG. 15shows an alternative fastening mechanism1503in which full ear loops suspend gas supply tubes below the ears. Fastening mechanism1503includes first over ear connector1597, guide connector1578, and first gas supply tube1502connected to nasal cannula body1504. First over ear connector1597is configured as a full loop shaped to hang over and around a first ear1591of a patient. First over ear connector1597is coupled at a bottom point, configured to be at the bottom of the ear, to first tube guide connector1578. Guide connector1578has a similar shape as guide connector1078inFIG. 10such that guide connector is configured as a column having openings at either end sized to fit first gas supply tube1502and having a slit between the openings such that first gas supply tube1502can be inserted into guide connector1578and held in place. Guide connector1578may be coupled to first over ear connector1597at an angle such that when first gas supply tube1502is inserted into guide connector1578it is held in a particular orientation on a patient's face. First gas supply tube1502is inserted into guide connector1578and is supported by first over ear connector1597on first ear1591. First gas supply tube1502supplies gas to nasal cannula body1504and through first nasal prong1518to a patient's nare. First gas supply tube1502is held in a position such that first nasal prong1518is appropriately oriented in a patient's nare to provide continuous and effective respiratory therapy.

Although only first gas supply tube1502is shown in fastening mechanism1503, second gas supply tube1528is supported by a similar over ear loop over the second ear (not shown). Supporting the first gas supply tube1502and second gas supply tube1528with over ear connectors such that the first gas supply tube1502and second gas supply tube1528pass under the ear prevents chafing and irritation of the sensitive tissue about the ears. During use, the first gas supply tube1502and second gas supply tube1528may rub or become warm, particularly when used with HFT, which can cause discomfort and lead to development of MDRPUs with extended use. Supporting and orienting the first gas supply tube1502and second gas supply tube1528on the patient's face without placing the first gas supply tube1502and second gas supply tube1528over the ears prevents discomfort and irritation while affixing the gas supply tubing and nasal cannula to a patient.

In some implementations, guide connector1578is sized to fit small-bore tubing. In other implementations, guide connector1578is sized to fit wide-bore tubing or any other size of medical tubing. In some implementations, first over ear connector1597is produced in different sizes to fit a variety of patient ears. In some implementations, first over ear connector1597is flexible or elastically stretchable in order to fit a variety of shapes and sizes of ears. In some implementations, first over ear connector1597and guide connector1578are separate pieces which may be individually selected and coupled together in order to fit a patient. In some implementations, additional cushions, padding, or fabric encasement is used in conjunction with first over ear connector1597to provide additional comfort to the patient.

WhileFIGS. 13-15show fastening mechanisms in which the gas supply tube passes under the ear,FIG. 16shows an illustrative view of a fastening mechanism1603using a fluid filled cushion1661to allow the first gas supply tube1602to pass over and around first ear1691without causing patient discomfort. Fastening mechanism1603includes fluid filled cushion1661, guide connector1678, first gas supply tube1602, and nasal cannula body1604. Fluid filled cushion1661rests against first ear1691between first ear1691and first gas supply tube1602in guide connector1678. Fluid filled cushion1661prevents first gas supply tube1602from contacting the sensitive skin surrounding first ear1691. Fluid filled cushion1661protects the skin around first ear1691from rubbing on the plastic gas supply tubing and from heat that may accompany the flow of gas through first gas supply tube1602. Fluid filled cushion1661is coupled to guide connector1678. Guide connector1678is configured as a split tube sized to fasten to first gas supply tube1602to hold first gas supply tube1602in place over first ear1691.

Fluid filled cushion1661may be a pre-filled balloon or foam cushion which acts as an air cushion over first ear1691. Fluid filled cushion1661may collapse slightly behind first ear1691to help secure first gas supply tube1602and nasal cannula body1604in place such that first nasal prong1618is properly positioned in the nare. Slightly collapsed fluid filled cushion1661may prevent slipping and rubbing about and behind the ear. In some implementations, fluid filled cushion1661completely surrounds the ear. In other implementations, fluid filled cushion1661is long enough to cover a top of the ear or a top and back portion of the ear. In some implementations, fluid filled cushion1661is about 3 to 8 inches in length. In some implementations, fluid filled cushion1661is used without guide connector1678and first gas supply tube1602rests directly on fluid filled cushion1661over first ear1691.

FIG. 17shows an illustrative view of first head strap1783and second head strap1787for use with gas supply tubing of a nasal cannula. First head strap1783has a first strap closure1781. Second head strap1787has a second strap closure1789. First head strap1783is configured to extend from behind a first ear1791along the nape of the neck just below the occipital curvature at the posterior-inferior portion of the head to a second ear (not shown). First strap closure1781at an end of first head strap1783is configured to retain first gas supply tube1702behind first ear1791without contacting first ear1791. Second head strap1787is configured to extend sagittally from first ear1791across a top of the head to the second ear (not shown). Second strap closure1789at an end of second head strap1787is configured to retain first gas supply tube1702above first ear1791without contacting first ear1791such that first gas supply tube1702is suspended above and behind first ear1791without contacting first ear1791. First head strap1783and second head strap1787are configured to also hold a second gas supply tube (not shown) above and behind a second ear in the same fashion. Suspending gas supply tubes above the ears of a patient prevents irritation around the patient's ears due to heat and pressure from the gas supply tube.

First strap closure1781and second strap closure1789may be Velcro, tape or any other clasping mechanism which encloses first gas supply tube1702. In some implementations, first strap closure1781and second strap closure1789are composed of stretchable material such as a fabric, polyurethane, rubber or neoprene, or any other suitable material. In some implementations, only first head strap1783is required. In some implementations, additional head straps may be required. First head strap1783and second head strap1787may be used alone or in combination with other fastening devices, such as those disclosed herein.

FIG. 18shows an illustrative view of a fastening mechanism1803configured as a strap system for use with a gas supply tubing of a nasal cannula. Fastening mechanism1803includes sagittal head strap1859, sagittal strap arm1857, sagittal strap clasp1855, occipital head strap1851, occipital strap arm1853, occipital strap clasp1858, and halo connecting strap1849. Sagittal head strap1859is configured to extend sagittally over a top portion of a patient's head. Sagittal strap arm1857is configured to loop under first gas supply tube1802and double back over itself to retain first gas supply tube1802above first ear1891. Sagittal strap arm1857is held in place by sagittal strap clasp1855. Occipital head strap1851is configured to extend about a patient's head in the posterior inferior region of the head, near or below the occipital bone. Occipital strap arm1853at an end of occipital head strap1851is configured to extend under first gas supply tube1802a double back over itself to be clasped in place by occipital strap clasp1858. Occipital strap arm1853retains first gas supply tube1802and suspends first gas supply tube1802behind first ear1891. Occipital head strap1851and sagittal head strap1859are connected by halo connecting strap1849, such that sagittal head strap1859, halo connecting strap1849and occipital head strap1851are connected in a circle about a crown of the head with occipital strap arm1853and sagittal strap arm1857extending out toward the ear. Although only one each of occipital strap arm1853and sagittal strap arm1857are shown, fastening mechanism1803includes a total of four straps, including a second occipital strap arm and second sagittal strap arm in the mirror image of those shown, the second occipital strap arm and second sagittal strap arm suspending second gas supply tube (not shown) above and behind a second ear in the same fashion.

Fastening mechanism1803is easily manufactured from a single material using a punch or die cut. In some implementations, fastening mechanism1803is constructed from a stretchable material such that the material conforms to the patient's head. In some implementations, fastening mechanism1803is constructed from hypoallergenic and/or breathable material, such as polyurethane foam, polyester or nylon fabric. In some implementations, sagittal strap clasp1855and occipital strap clasp1858are Velcro, reusable tape, or clips, or any suitable non-slip fastener to retain first gas supply tube1802away from first ear1891. Sagittal strap arm1857is configured to pull first gas supply tube1802away from a top of first ear1891, such that first gas supply tube1802is not in contact with first ear1891. Occipital strap arm1853is configured to pull first gas supply tube1802away from a lower part of first ear1891towards the center of the nape of the neck. Nasal cannula body1804is affixed to the patient in this manner, without first gas supply tube1802contacting and irritating first ear1891or the sensitive skin around it. Fastening mechanism1803securely suspends first gas supply tube1802above first ear1891, decreasing incidence of chafing, blistering, and ulcers while securing the nasal cannula body1804in a position on the patient.

FIG. 19shows an illustrative view of a fastening mechanism1903including a headband1971for use with gas supply tubing of a nasal cannula having a raised section with a channel for retaining gas supply tubing.FIG. 20shows a view of an end of a strap operating by a similar mechanism as the headband inFIG. 19. Fastening mechanism1903includes headband1971, first band end1917, second band end1919, first raised section1979including first groove1973, and second raised section1969including second groove1963. First band end1917of headband1971comprises first raised section1979formed as a circular raised piece having first groove1973about the outside. First groove1973is sized to accept first gas supply tube1902and to retain first gas supply tube1902above or behind first ear1991of a patient. Headband1971is sized to retain first gas supply tube1902above and behind first ear1991on first groove1973of first raised section1979and to retain second gas supply tube1928above and behind second ear1993on second groove1963of second raised section1969. Headband1971may be manufactured in a variety of lengths from first band end1917to second band end1919, or, alternatively, may have adjustable length. First gas supply tube1902fluidically attached to nasal cannula body1904is suspended from first band end1917of headband1971where it is retained in first groove1973about first raised section1979. Second gas supply tube1928is coupled to nasal cannula body1904and is suspended from second band end1919of headband1971. Similarly to first gas supply tube1902, second gas supply tube1928is retained in second groove1963about second raised section1969. First gas supply tube1902and second gas supply tube1928are affixed to the patient's face by first groove1973and second groove1963without first gas supply tube1902and second gas supply tube1928contacting the ears. Affixation of first gas supply tube1902, second gas supply tube1928and nasal cannula body1904to the patient without suspending first gas supply tube1902and second gas supply tube1928from first ear1991and second ear1993decreases incidence of irritation and development of MDRPU. In particular, affixation of nasal cannula body1904used for HFT to a patient without hot and pressurized first gas supply tube1902and second gas supply tube1928rubbing a patient's ear is important to patient comfort.

In some implementations, first groove1973and second groove1963are configured to accept wide-bore gas supply tubing, small-bore gas supply tubing or any other medical tubing. In some implementations, first groove1973and second groove1963are channel-like and maintain first gas supply tube1902and second gas supply tube1928in a position. In other implementations, first groove1973and second groove1963allow first gas supply tube1902and second gas supply tube1928to slide through first groove1973and second groove1963. In some implementations, more than one headband1971is used to secure first gas supply tube1902and second gas supply tube1928to a patient and to suspend first gas supply tube1902and second gas supply tube1928above and behind first ear1991and second ear1993of a patient.

Similarly to fastening mechanism1903inFIG. 19,FIG. 20shows a view of the end of a head strap also having a channel for securing supply tubing over an ear.FIG. 20includes head strap2071, first raised section2079, first groove2073and first gas supply tube2002. First gas supply tube2002is secured in first groove2073about first raised section2079. First gas supply tube2002is held above first ear2091by head strap2071. In some implementations, head strap2071is a head band similar to headband1971inFIG. 19. Use of head strap2071prevents first gas supply tube2002from contacting first ear2091and causing discomfort.

While fastening mechanism1903ofFIG. 19includes raised sections on which gas supply tubing is attached, in some implementations the raised sections are shaped to mimic a human ear. For example,FIG. 21shows an illustrative top view of an alternate fastening mechanism2103including another embodiment of a headband2171with first raised section2179shaped like a human ear for restraining gas supply tubing of a nasal cannula above the ear of a patient. Fastening mechanism2103includes headband2171, first raised section2179, first groove2173, and cut-out2165. Headband2171includes at first band end2117first raised section2179with first groove2173about a top portion2115of first raised section2179. First raised section2179also includes cut-out2165. Headband2171is configured to extend over a patient's head such that first raised section2179is positioned above the ear of a patient. First groove2173in top portion2115of first raised section2179provides a channel or guide in which gas supply tubing (not shown) is restrained in order to keep the gas supply tubing from rubbing on or near the ear. In some implementations, cut-out1165provides space for a patient's ear. In other implementations, no cutout is required. First raised section2179is formed to simulate the contour of an ear, such that first raised section2179and first groove2173form a suspended artificial ear over which gas supply tubing for a nasal cannula (not shown) is looped.

The suspension of the gas supply tubing over first raised section2179above the patient's ear decreases the heat and friction which lead to the development of MDRPUs and increase patient comfort. First groove2173on first raised section2179supports the gas supply tubing over the patient's ear, protecting the patient's ear from friction and compression. In some implementations, headband2171is composed of a non-slip, flexible material which conforms to a patient's head. For example, headband2171may be comprised of polyethylene, high density polyethylene, polyvinyl chloride, low density polyethylene, polypropylene, polystyrene, polycarbonate, or any other suitable material. In some implementations, headband2171is formed as a wide band. In other implementations, headband2171is formed as a narrow band. In other implementations, headband2171is formed from a semi-rigid mesh. In other implementations, headband2171is formed of a stretchable material such as silicone rubber. In some implementations, headband2171includes perforations for enhanced air circulation at a patient's scalp. In some implementations, first raised section2179includes a gel pad on the patient-facing surface for enhanced comfort by reducing friction. In other implementations, headband2171includes comb teeth on a patient-facing surface or edge for improved placement and support on a patient's head. In some implementations, headband2171is adjustable. In other implementations, headband2171is manufactured in a variety of sizes, e.g., sizes to fit neonates, pediatric patients and adult patients.

In other implementations, headband2171is configured to be worn about a backside of the patient's head as an occipital support. In such implementations, an additional strap may extend from each end of headband2171about the forehead of the patient. The headband may be adjustable with Velcro or other closures. The placement of headband2171as an occipital support permits firm placement and resistance to any ‘tug’ of the nasal cannula gas tubing during use. First raised section2179may include first groove2173as a channel bonded to first raised section2179.

Fastening mechanism2103may be used in conjunction with any respiratory therapy requiring gas supply tubing to be restrained about a patient's ears. In some implementations, fastening mechanism2103is used with a nasal cannula for use with an HFT system. In such implementations, first raised section2179and first groove2173suspend heated and distended gas supply tubing above a patient's ears in order to prevent rubbing and sweating that may lead to development of pressure ulcers.

The nasal cannulae and fastening devices described above can be incorporated into a respiratory therapy system, such as the illustrative respiratory therapy system2207shown inFIG. 22. The respiratory therapy system2207includes nasal cannula body2204, first connector2210, tubing guide2275, first gas supply tube2202, second gas supply tube2228, slidable connector2285, console2241, display screen2243, controls2245, first gas supply tube port2239, and second gas supply tube port2247. Console2241includes display screen2243and controls2245that allow a user to control aspects of the respiratory therapy being delivered, such as the flow-rate of breathing gas, mixing ratio of breathing gases, administration of aerosolized medicament, or temperature of gas. Display screen2243may also display current settings to a user, as well as displaying warnings, for example, if there is a kink or leak in a supply tube which diminishes the gas flow. In some implementations, console2241includes a breathing gas source, compressor, gas blender, medicament source, or a nebulizer. In some implementations, console2241includes a heater and liquid reservoir. In some implementations, console2241controls a gas flow rate of over 8 LPM. In some implementations, console2241controls a gas flow rate of over 20 LPM.

Breathing gas flows from console2241to first gas supply tube2202through first gas supply tube port2239and from console2241to second gas supply tube2228through second gas supply tube port2247. Breathing gas then flows through first gas supply tube2202and second gas supply tube2228to nasal cannula body2204. First gas supply tube2202and second gas supply tube2228can be affixed to a patient's face using any fastening mechanism or combination of mechanisms described here, such as901,1075,1285,1303,1803,1903, or2103shown inFIGS. 9, 10, 12, 13, 18, 19, and 21. For example, first gas supply tube2202and second gas supply tube2228can be affixed to a patient's face with tubing guide2275which retains the first gas supply tube2202in an orientation on one of the patient's cheeks and retains second gas supply tube2228on the other cheek. Tubing guide2275allows a user to remove and replace first gas supply tube2202and second gas supply tube2228such that when first gas supply tube2202and second gas supply tube2228is replaced in tubing guide2275, first gas supply tube2202and second gas supply tube2228are placed into a proper orientation with respect to the nasal cannula body2204and facial anatomy of the patient. First gas supply tube2202and second gas supply tube2228are shown draped over first ear2091and second ear2093of the patient, but in other implementations first gas supply tube2202and second gas supply tube2228can be used with any other fastening mechanism to keep the first gas supply tube2202and second gas supply tube2228away from sensitive skin surrounding a patient's ears.

In another example, first gas supply tube2202and second gas supply tube2228of respiratory therapy system2207can be coupled to nasal cannula body2204at first connector2210, such as swivel connector901, which permits rotation and swivel motions such that movement of first gas supply tube2202and second gas supply tube2228is not transferred to nasal cannula body2204. Thus, nasal cannula body2204is maintained in a proper positioning despite motion or movement of first gas supply tube2202and second gas supply tube2228. First gas supply tube2202and second gas supply tube2228can also be used with slidable connector2285, similar to slidable connector1285, to retain first gas supply tube2202and second gas supply tube2228under the chin of the patient to securely affix the nasal cannula body2204to the patient's face while keeping the first gas supply tube2202and second gas supply tube2228from kinking.

Furthermore, respiratory therapy system2207may be used with any of the previously described nasal cannulae, including100,200,300,500,700, and800described inFIGS. 1, 2, 3,5,7, and8. Respiratory therapy system2207may be used with a nasal cannula body2204that allows a rotation of nasal prongs such that the position of the nasal prong in a patient's nare is adjustable to account for differences in nasal anatomy or nare size. The adjustment of nasal prong positioning permits the administration of respiratory therapy without the discomfort to the patient associated with contact of the nasal prongs with sensitive tissues in the nare or the misdirected flow of breathing gas onto nasal tissues.

The appropriate orientation of nasal prongs in a patient's nares and the secure affixing of the nasal cannula and gas supply tubes in proper position allow respiratory therapy system2207to provide effective therapy to a patient. Correctly directing breathing gas, and, in particular, heated and humidified breathing gas for HFT, into the nasal passageway promotes flushing of the upper respiratory passageways for therapeutic effect. The appropriate orientation of the nasal prongs in the nares also decreases patient discomfort associated with poor positioning leading to rubbing or contact of the nasal prongs in the nare or irritation of the mucosa due to misdirected breathing gas flow. Restraining supply gas tubing and securing the positioning of the nasal cannula further increases the occurrence of successful therapeutic outcomes. Supply gas tubing restraints which protect the sensitive tissues surrounding the ears from irritation and development of ulcers increase patient comfort and patients are less likely to move or adjust gas supply tubes which are not causing irritation. These devices improve therapeutic outcomes by ensuring that effective respiratory therapy is delivered to a patient.

The foregoing is merely illustrative of the principles of the disclosure, and the apparatuses can be practiced by other than the described embodiments, which are presented for purposes of illustration and not of limitation. It is to be understood that the apparatuses disclosed herein, while shown for use in high flow therapy systems, may be applied to systems to be used in other ventilation circuits.

Variations and modifications will occur to those of skill in the art after reviewing this disclosure. The disclosed features may be implemented, in any combination and subcombination (including multiple dependent combinations and subcombinations), with one or more other features described herein. The various features described or illustrated above, including any components thereof, may be combined or integrated in other systems. Moreover, certain features may be omitted or not implemented.

Examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the scope of the information disclosed herein. All references cited herein are incorporated by reference in their entirety and made part of this application.