Flow triggered gas delivery

Abstract

A fluid delivery system responds to inspiration by delivering fluid, such as supplemental oxygen, to a patient. The fluid delivery system includes a valve assembly that is triggered by sensing the onset of inspiration by measuring temperature changes in the airflow within a nasal or oral cannula, mask, or helmet.

Description

Technical Field

[0001] This disclosure relates to apparatus and methods for monitoring and delivering oxygen or other gases to humans or other animals, and for efficiently preserving the delivery of said gases. This disclosure has a particular use in delivering supplemental oxygen to human or animal patients, and will be described in conjunction with this use, although other uses are also contemplated. Background Technology

[0002] In the United States, more than 1.5 million patients are currently receiving supplemental oxygen therapy, at a cost believed to exceed $2 billion annually. Furthermore, acute cases of COVID-19 have exacerbated the demand for supplemental oxygen, pushing some hospitals to the point of nearing oxygen depletion.

[0003] Most patients receiving long-term supplemental oxygen therapy (LTOT) suffer from chronic hypoxemia due to chronic obstructive pulmonary disease (COPD). There is currently no cure for this condition. However, the adverse effects of chronic hypoxemia can be mitigated through the administration of LTOT. Continuous inhalation of a low flow rate of oxygen, typically 2-3 lpm (liters per minute), from a nasal cannula increases the concentration of oxygen in the patient's breath. It is estimated that for every 1 lpm of flow, the overall inhaled concentration increases by 3-4%. This increase in oxygen concentration compensates for the impaired oxygen absorption capacity of the patient's lungs.

[0004] Typically, when a patient is diagnosed with chronic hypoxemia, a fixed-flow oxygen therapy is prescribed based on a 20-minute titration test performed in the doctor's office. During the test, the patient's blood oxygen saturation is measured using an invasive blood gas analyzer or a non-invasive device such as a pulse oximeter. When measuring blood saturation (SpO2), the patient may be asked to walk on a treadmill to measure their need for supplemental oxygen during exercise. Based on this brief test, a fixed-flow supplemental oxygen therapy is prescribed. The patient may be advised to increase the flow rate of supplemental oxygen during activity (e.g., climbing stairs, sleeping, or experiencing shortness of breath). The appropriateness of supplemental oxygen therapy will need to be confirmed, with the goal of maintaining the patient's oxygen saturation above 90% during all activities, including sleep. Some patients may require supplemental oxygen to breathe 24 hours a day, or may only need supplemental oxygen while walking, or may only need supplemental oxygen therapy during sleep. Among patients who require LTOT while awake, a higher flow rate is often needed during sleep. It is common practice to increase the flow rate by 1 liter per minute when the patient is sleeping.

[0005] If a patient needs supplemental oxygen even at rest, he or she will have a fixed oxygen generator in his or her home, which can be set to produce, for example, up to 5 liters per minute of 93% oxygen. Typically, this unit is now manually set to a prescribed flow rate in liters per minute. If the patient needs supplemental oxygen while moving, he or she will usually carry a small hyperbaric oxygen cylinder or a small refillable liquid oxygen Dewar flask. Small portable oxygen concentrators can also be used, which can produce up to 3 liters per minute of continuous oxygen or deliver pulsed oxygen at higher flow rates. These portable oxygen delivery systems all have disadvantages. Portable concentrators are generally larger, noisier, and have relatively shorter battery life. Small hyperbaric oxygen cylinders have limited capacity, especially the smaller ones, but they do not require batteries and do not produce the same noise as concentrators.

[0006] Due to the cost of providing oxygen for walking in small vials and Dewar flasks, various oxygen preservation devices have been developed to conserve oxygen flow. These prior art oxygen preservation devices deliver only short pulses of oxygen at the beginning of the patient's inhalation. By not delivering oxygen during exhalation or the later stages of inhalation, oxygen is preserved without affecting the increase in the patient's oxygen saturation. Two types of oxygen preservation devices, pneumatic and electronic, are currently available, claiming to achieve oxygen preservation ratios from 2:1 to 7:1 compared to continuous oxygen delivery. Such high preservation ratios are achieved through electronic devices programmed to skip breaths so that an oxygen pulse is delivered every other breath. However, electronic devices cannot be used for all walking patients because such high preservation ratios can actually lead to poor oxygen saturation, especially during periods of increased oxygen utilization, such as during vigorous walking or climbing stairs.

[0007] Furthermore, currently available preservation devices measure the drop in nasal pressure, which is insufficient for many patients to trigger oxygen release in a variety of situations, including: extremely reduced respiratory function; predominantly mouth breathing; talking while walking; walking rapidly or engaging in vigorous conversation; or while sleeping. After activating these dynamic devices, patients are “taught” to focus on nasal breathing to help trigger the device. Patients typically need to stop their activity and focus on their nasal breathing, or have a nasal cannula probe inserted into their mouth to more effectively trigger the device.

[0008] The pressure sensing at the start of inhalation in electronic oxygen preservers is currently accomplished using one of the following two methods:

[0009] 1. Some existing technologies employ a dual-lumen cannula, with one lumen dedicated to pressure sensing and the other to oxygen delivery. This design aims to be more sensitive to the onset of inhalation, but it has the drawback of only being able to deliver oxygen to one nasal passage.

[0010] 2. Other designs use a single-lumen cannula, which typically has pressure sensors attached to a T-shaped piece below the two nasal prongs. The total pressure drop associated with inhalation is detected from both nasal passages, and oxygen is then delivered to both nasal passages.

[0011] Both designs delay the triggering of oxygen flow due to the inherent hysteresis in pressure sensing. However, even a slight delay in triggering oxygen flow is easily noticeable to the patient. Another drawback of current designs using pressure sensors is that if one of the patient's nasal passages is blocked, it will interfere with oxygen detection and delivery.

[0012] Another drawback of current oxygen generation systems is the fact that a patient's ideal oxygen requirement can change over time, both in the short term due to varying exercise and in the long term due to improvements or deterioration in health. When physicians prescribe a fixed flow rate of oxygen, their primary concern is ensuring that the patient's blood saturation does not fall below 88-89% oxygen saturation. Physicians do not want patients to experience desaturation below 90% oxygen during any activity. Although there are theoretical concerns about the potential toxicity of patients receiving prolonged high concentrations (above 50%) of oxygen (e.g., absorptive atelectasis, increased oxidative stress, and inflammation), clinical experience provides little support for these concerns in LTOT settings. (“Long-term supplementary oxygen therapy.” Up-To-Date; January 18, 2013. Brian L. Tiep, MD; Rick Carter, PhD, MBA).

[0013] According to a study by Fussell et al., current oxygen therapy protocols are prone to error (RespiratoryCare. February 2003, Vol. 48, No. 2). In that study, pulse oximetry was used to continuously monitor the blood saturation levels of 20 patients with COPD to determine whether each patient's oxygen prescription was sufficient to maintain his or her saturation. The study concluded that there was a poor correlation between routine oxygenation assessment methods and continuous dynamic oxygenation measurement during LTOT screening of COPD patients. Recently, in an article entitled "Critical Comparisons of the Clinical Performance of Oxygen-conserving Devices" (Am.J.Respir.Crit.Care Med. May 15, 2010; 181(10):1061-1071), all current collections of pressure-sensing-based conservation devices were criticized for failing to meet their efficacy requirements. The authors claimed that "although each device is activated during nasal and mouth breathing, none of them function consistently as engineered."

[0014] When patients achieve hypoxemia while using a conservation device or a fixed oxygen flow rate, the natural reaction is to simply increase the flow rate. However, hypoxemia is often caused by a delay in triggering the supplemental oxygen flow rate too early at the start of inhalation. Increased nasal flow rates become increasingly expensive and are often poorly tolerated. Some COPD patients using a stationary oxygen concentrator at home face financial difficulties and concerns about the electricity costs of continuous operation. In many cases, this leads to adherence problems, where patients may choose not to turn on the concentrator and not follow their doctor's prescribed treatment to save on their electricity bills. Furthermore, these concentrators emit significant amounts of heat into the room, which can further increase energy costs, i.e., the cost of cooling the room. Current oxygen concentrator designs typically produce a maximum flow rate of, for example, 5 liters per minute. If a patient's rest prescription is 2 liters per minute, the patient can set the flow rate through their cannula to the desired flow rate, and the excess oxygen being produced is simply pushed into the nostrils, which may be wasted while breathing through the mouth. Many oxygen therapy patients may spend significant amounts of time with unacceptable levels of oxygen saturation during activity, conversation, naps, or sleep.

[0015] Current pressure-based oxygen delivery units fail to meet patients' needs when they are mouth-breathing during more strenuous activities, talking, eating, and / or sleeping. Patients receiving dynamic oxygen often have to stop and focus on nasal breathing, or place a nasal cannula fork in their mouth and suck on it to trigger oxygen release. When oxygen demand is not met, a simple workaround is to increase nasal flow, which leads to increased discomfort and dryness in the nasal passages, and sometimes even nasal bleeding. Furthermore, patients frequently stop the oxygen delivery system entirely while eating.

[0016] In my previous U.S. Patent 9,707,366, I described an improved system, method, and apparatus for the controlled delivery of oxygen to a patient, wherein a nasal cannula or combined naso-oral cannula is equipped with a valve assembly and a flow sensor for sensing “flow leakage” through the patient’s nasal cavity during breathing. This “hidden signal,” combined with simultaneous monitoring of nasal and / or oral flow patterns, prevents the on-demand oxygen delivery system from experiencing uncertain or misdirected oxygen delivery—both of which can lead to wasted oxygen or insufficient oxygen delivery to the patient. More specifically, my previous '366 patent describes a fluid delivery system comprising: at least one fluid source; at least one valve assembly connected to said at least one fluid source, wherein the at least one valve assembly is configured to allow fluid to flow out of the at least one source during patient inspiration; an outlet including a nasal or oral cannula in fluid communication with the at least one valve assembly; and a nasal flow sensor for triggering fluid delivery in response to patient inspiration. The fluid delivery system also includes a power source configured to operate the at least one valve assembly. The nasal flow sensor can be located in or near a nasal or oral cannula, near a fluid source, or in an air tube between the nasal or oral cannula and at least one fluid source. Summary of the Invention

[0017] This disclosure improves upon the method and apparatus of my previous '366 patent by providing an improved triggering mechanism for actuating a valve to release fluid from a fluid source for delivery through a nasal or oral cannula to a patient. The fluid delivered by this method may include oxygen. More specifically, in one aspect, this disclosure provides a flow sensor employing a heater and a temperature sensor to detect the onset of inspiration by measuring the temperature difference caused by convective cooling resulting from fluid flow, and to trigger flow within approximately less than 20 milliseconds of the onset of inspiration, typically within 10-20 milliseconds, which is significantly better than any pressure sensor currently available.

[0018] Furthermore, in order to allow the use of a highly sensitive air flow sensor and protect the sensor from the high-pressure oxygen flow, this disclosure preferably isolates the air flow sensor from the oxygen flow line by means of a switching valve.

[0019] In one aspect of this disclosure, a fluid delivery system is provided for the controlled delivery of fluid to a human or animal, comprising: at least one fluid source; at least one valve assembly connected to the at least one fluid source, wherein the at least one valve assembly is configured to allow flow of the fluid from the at least one source during inhalation of the human or animal; an outlet end including a nasal or oral cannula in fluid communication with the at least one valve assembly; and a flow sensor for triggering fluid delivery in response to inhalation of the human or animal, wherein the flow sensor is in fluid communication with and upstream of the nasal or oral cannula, and includes a temperature sensor, such as a thermistor, configured to detect a temperature change indicating the onset of inhalation of the human or animal within approximately less than 20 milliseconds, typically within 10-20 milliseconds. The system may also include a power supply configured to operate the at least one valve assembly.

[0020] In another aspect of this disclosure, the flow sensor is located in or near the nasal or oral cannula, or in a tube connecting the nasal or oral cannula and at least one of the fluid sources. The nasal and oral cannulas may be connected to each other. Preferably, the delivered fluid preferably includes supplemental oxygen, therapeutic gas, or anesthetic gas.

[0021] In one embodiment, the fluid delivery system includes electronic circuitry for controlling at least one valve assembly based on a signal from a flow sensor. Preferably, the electronic circuitry includes a trigger mechanism for initiating the release of the fluid via the at least one valve assembly.

[0022] The fluid delivery system may also include a heater configured to heat the fluid upstream of the flow sensor to a temperature above ambient.

[0023] In a preferred embodiment, the temperature sensor is configured to detect the onset of inhalation and exhalation by directional changes in temperature, and wherein the system optionally includes heaters located upstream and optionally downstream of the temperature sensor.

[0024] In another embodiment, the flow sensor is isolated from at least one of the fluid sources via a piezoelectric actuator valve.

[0025] This disclosure also provides an apparatus for conserving fluid delivered from a fluid supply to a person or animal, comprising: a fluid conservator controller connected between the fluid supply and a nasal or oral cannula, wherein the controller includes at least one valve selectively triggered to deliver the fluid to the nasal or oral cannula; a flow sensor configured to sense inhalation in the person or animal; and a triggering mechanism communicating with the sensor to activate the conservator controller, wherein the flow sensor is in fluid communication with the nasal or oral cannula and includes a temperature sensor, such as a thermistor, configured to detect a temperature change indicating the onset of inhalation in the person or animal within approximately less than 20 milliseconds, typically within 10-20 milliseconds.

[0026] In one embodiment of this disclosure, the flow sensor and the triggering mechanism are located far apart from each other, and the flow sensor and the triggering mechanism are connected by wired or wireless communication.

[0027] In a preferred embodiment of this disclosure, the flow sensor and the triggering mechanism are located far apart from each other, and the flow sensor and the triggering mechanism are connected by wired or wireless communication.

[0028] In a preferred embodiment of this disclosure, at least one valve includes at least one valve, and the fluid supply preferably includes oxygen, therapeutic gas, or anesthetic gas.

[0029] In one embodiment, the device further includes electronic circuitry for controlling at least one valve based on a signal from a flow sensor, and / or a heater configured to heat the flow sensor or fluid upstream of the flow sensor to a temperature above ambient.

[0030] In one embodiment, the temperature sensor is configured to detect the onset of inhalation and exhalation by directional changes in temperature, and the system optionally includes heaters located upstream and optionally downstream of the temperature sensor.

[0031] In another implementation, the flow sensor is isolated from the fluid supply via a piezoelectric actuator valve.

[0032] This disclosure also provides a method for preserving fluid delivery from the fluid source to a patient, comprising the steps of: providing a valve in communication with the fluid source and a nasal or oronasal cannula worn by the patient; sensing the onset of inhalation by detecting a temperature change in the airflow through the nasal or oronasal cannula within approximately 15-20 milliseconds after the onset of inhalation using a flow sensor including a temperature sensor such as a thermistor in communication with the nasal or oronasal cannula; and triggering the valve in response to the sensed onset of inhalation to release the fluid from the fluid source for delivery to the patient via the nasal or oronasal cannula, preferably, the fluid including oxygen, a therapeutic gas, or an anesthetic gas.

[0033] In one embodiment, the method includes heating the flow sensor or fluid upstream of the flow sensor to a temperature above ambient temperature.

[0034] In another embodiment, the flow sensor includes a temperature sensor configured to detect the onset of inhalation and exhalation by directional changes in temperature.

[0035] In another embodiment, the method includes the step of isolating the flow sensor from the fluid source when sensing the start of inhalation.

[0036] This disclosure also provides a fluid delivery system for controlling the delivery of fluid to a person or animal, comprising:

[0037] At least one of the fluid sources;

[0038] At least one valve assembly connected to the at least one fluid source, wherein the at least one valve assembly is configured to allow flow of fluid from the at least one source during the inhalation of the person or animal;

[0039] The outlet end includes a nasal or oral cannula, mask, or helmet in fluid communication with at least one valve assembly; and

[0040] A flow sensor is used to trigger fluid delivery in response to the inhalation of the person or animal.

[0041] The flow sensor is in fluid communication with and upstream of a nasal or oral cannula, mask, or helmet, and includes a temperature sensor configured to detect a temperature change indicative of the onset of inhalation in the human or animal within less than about 20 milliseconds, preferably 10-20 milliseconds.

[0042] At least one of the valve assemblies is configured to deliver fluid flow gradually to match the breathing patterns of a human or animal.

[0043] In one embodiment, the fluid delivery system includes a power source configured to operate at least one valve assembly.

[0044] In another embodiment, the flow sensor is located in or near a nasal or oral cannula, mask, or helmet, or in a tube connecting the nasal or oral cannula, mask, helmet, or oral cannula and at least one of the fluid sources.

[0045] In yet another implementation, the nasal cannula and the oral cannula are connected to each other.

[0046] In yet another embodiment, the fluid being transported includes supplemental oxygen, therapeutic gas, or anesthetic gas.

[0047] In a fourth embodiment, the fluid delivery system includes electronic circuitry for controlling at least one valve assembly based on a signal from a flow sensor. This electronic circuitry preferably includes a trigger mechanism for initiating the release of the fluid via the at least one valve assembly.

[0048] In a particularly preferred embodiment, the at least one valve assembly is configured to cause a gradual change in fluid flow from an initial flow rate of 15-40%, preferably 20-35%, more preferably about 33% of the inhalation capacity of a person or animal at the time of triggering, to 100% flow rate.

[0049] In another embodiment, the fluid delivery system further includes a heater configured to heat fluid upstream of or above the flow sensor to above ambient temperature, and, if desired, a temperature sensor configured to detect the onset of inhalation and exhalation by directional changes in temperature, wherein the system optionally includes heaters located upstream and optionally downstream of the temperature sensor.

[0050] In another embodiment, the flow sensor is isolated from at least one of the fluid sources via a piezoelectric actuator valve.

[0051] This disclosure also provides an apparatus for storing fluid supplied from a fluid supply to a person or animal, comprising:

[0052] A fluid reservoir controller connected between a fluid supply and a nasal or oral cannula, mask, or helmet, wherein the controller includes at least one valve that is selectively triggered to deliver the fluid to the nasal or oral cannula, mask, or helmet.

[0053] A flow sensor configured to sense the inhalation of a human or animal; and

[0054] A triggering mechanism, which communicates with the flow sensor to activate the preserver controller, wherein the flow sensor is in fluid communication with the nasal or oral cannula, mask, or helmet, and includes a temperature sensor configured to detect a temperature change indicating the onset of the inhalation of the person or animal within approximately less than 20 milliseconds, preferably 10-20 milliseconds, at the start of the inhalation, wherein at least one valve assembly is configured to cause a gradual change in fluid flow delivery to coordinate the breathing pattern of the person or animal.

[0055] In one embodiment of the device, the flow sensor and the triggering mechanism are located far apart from each other, and the flow sensor and the triggering mechanism are connected to each other via wired or wireless communication.

[0056] In another embodiment of the device, the fluid supply includes oxygen, therapeutic gas, or anesthetic gas.

[0057] In a preferred embodiment, the device further includes electronic circuitry for controlling at least one valve based on a signal from a flow sensor, and optionally includes a heater configured to heat the flow sensor or fluid upstream of the flow sensor to above ambient temperature.

[0058] In a particularly preferred embodiment, at least one valve assembly is configured to gradually change the fluid flow rate from an initial flow rate of 15-40%, preferably 20-35%, more preferably about 33% at triggering to 100% of the flow rate at the inhalation capacity of a human or animal.

[0059] In another embodiment of the device, the temperature sensor is configured to detect the onset of inhalation and exhalation by directional changes in temperature, and the system optionally includes heaters located upstream and optionally downstream of the temperature sensor.

[0060] In another device, the flow sensor is isolated from the fluid supply via a piezoelectric actuator valve.

[0061] This disclosure also provides a method for preserving fluid delivery from a fluid source to a patient, comprising the following steps:

[0062] Provides a valve in communication with the fluid source and a nasal or oronasal cannula, mask, or helmet for the patient to wear;

[0063] Using a flow sensor connected to a nasal or oral cannula, mask, or helmet, the onset of inhalation is sensed by detecting temperature changes in the fluid passing through the nasal or oral cannula, mask, or helmet within approximately less than 20 milliseconds, preferably 10-20 milliseconds, at the onset of inhalation.

[0064] In response to a sensed initiation of inhalation, a valve is triggered to release the fluid from a fluid source for delivery to the patient via a nasal or oronasal cannula, mask, or helmet, wherein the valve assembly is configured to cause a gradual change in fluid flow delivery to coordinate with the breathing pattern of a person or animal.

[0065] In a preferred embodiment of the method, the fluid includes oxygen, therapeutic gas, or anesthetic gas, and optionally, the method further includes heating the flow sensor or the fluid upstream of the flow sensor to a temperature above ambient.

[0066] In another embodiment of the method, the flow sensor includes a temperature sensor configured to detect the onset of inhalation and exhalation by directional changes in temperature.

[0067] Another embodiment of the method includes the step of isolating the flow sensor from the fluid source when sensing the start of inhalation.

[0068] In another embodiment of the method, the valve assembly is configured to gradually change the fluid flow rate from an initial flow rate of 15-40%, preferably 20-35%, more preferably about 33% at triggering to 100% of the inhalation capacity of a human or animal. Attached Figure Description

[0069] This disclosure will be better understood by reading the following detailed description in conjunction with the accompanying drawings, in which similar reference numerals are used to indicate similar elements, and wherein:

[0070] Figure 1 and Figure 2 These are block diagrams of two different systems for fluid transport according to this disclosure;

[0071] Figure 3 This is a block diagram of a remote sensor and control according to a preferred embodiment of the present disclosure;

[0072] Figure 4 The triggering algorithm according to a preferred embodiment of the present disclosure is illustrated schematically;

[0073] Figure 5 This is a table comparing the system of this disclosure with conventional prior art systems employing pressure and flow sensors to begin with the airflow delivery;

[0074] Figure 6 A flowchart of the airflow transport described in this disclosure; and

[0075] Figure 7 It is a block flowchart depicting the airflow transport according to this disclosure. Detailed Implementation

[0076] As used in this article, "nasal intubation" is intended to include two intracavitary nasal cannulas and a nasal mask or pillowcase. "Oral intubation" is intended to include a face mask, a breathing tube, a sealing device, a diver's helmet, and a hazard helmet.

[0077] In the following description, embodiments will be described with reference to the accompanying drawings, wherein the same numerals denote the same or similar elements. Throughout the specification, references to "one embodiment," "some embodiments," or similar language mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of this disclosure. Therefore, throughout the specification, the phrase "in one embodiment" and similar language may, but do not necessarily, refer to the same embodiment.

[0078] The features, structures, or characteristics described in this disclosure can be combined in any suitable manner in one or more embodiments. Numerous specific details are set forth in the following description to provide a thorough understanding of embodiments of this disclosure. However, those skilled in the art will recognize that this disclosure can be practiced without one or more of these specific details or using other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0079] The fluid delivery system disclosed herein provides supplemental oxygen to a person or animal at intermittent time intervals based on the patient's tidal breathing. The fluid delivery system includes a nasal or oral-nasal flow-triggered valve assembly that opens in response to the patient's inspiration and closes during the inspiration phase to conserve oxygen that would otherwise be wasted filling the patient's "deadspace" before the end of inspiration. Specifically, this disclosure senses the onset of inspiration via a temperature sensor placed in the supply tubing in the case of a nasal cannula, oral cannula, or helmet, and triggers the opening of a regulating valve at the onset of inspiration (i.e., within approximately 15-20 milliseconds after the onset of inspiration), maintaining its open position for a period consistent with the human or animal's tidal breathing.

[0080] Nasal or oral flow temperature sensors are sensitive enough to detect the onset of inspiration in approximately less than 20 milliseconds, typically within 10-20 milliseconds, and send a signal to the valve assembly to open, allowing oxygen flow for a period of time. By opening no more than approximately 20 milliseconds after the onset of inspiration, typically within 10-20 milliseconds, and then maintaining the opening for a limited period, a truly on-demand oxygen delivery system can be achieved, eliminating uncertainty or misuse of oxygen—both of which lead to wasted oxygen or insufficient oxygen delivery to the patient. Utilizing flow information at the onset of inspiration eliminates the waste involved in, for example, pulsed oxygen therapy or continuous flow oxygen therapy. Furthermore, the patient or user experiences a pleasant sense of synchronization between the onset of breathing and oxygen delivery, and by eliminating any perceptible delay in oxygen delivery, can move freely and speak naturally without worrying about missing his or her oxygen rhythm. The efficiency of the device can also be maintained for hospitalized or bedridden patients receiving oxygen from a central fluid supply via a reliable pulsed oxygen delivery system.

[0081] Furthermore, unlike pressure flow sensors described in the prior art, the use of a temperature sensor, as disclosed in my publication, to sense and thus trigger is essentially instantaneous, i.e., within approximately less than 20 milliseconds of the onset of inhalation, typically within 10-20 milliseconds. Therefore, there is virtually no delay in the delivery of supplemental oxygen. There is also no oxygen waste compared to conventional pressure flow sensor detectors. Thus, the flow of supplemental oxygen is essentially initiated with the onset of inhalation and is timed to remain on for a period based on the slope of the patient's Cheyne-Stokes respiration and / or upon detection of the onset of exhalation. As a result, supplemental oxygen is preserved because it is not provided when the patient does not require it: during the filling of the "dead space" (i.e., the volume of inhaled air that does not participate in gas exchange) or during exhalation.

[0082] As used herein, inhalation and exhalation are used synonymously. Inhalation is the movement of air from the external environment through the airways into the lungs. During inhalation, the chest expands, and the diaphragm contracts downward or towards the tail, resulting in expansion of the pleural cavity and negative pressure within the pleural cavity. This negative pressure causes airflow primarily from the nose or mouth into the pharynx (larynx) and trachea, eventually reaching the lungs. By using a flow sensor in the form of a temperature sensor, the determination of the onset of inhalation is essentially instantaneous, i.e., within approximately less than 20 milliseconds of the onset of inhalation, typically within 10–20 milliseconds, utilizing the most critical phase of inhalation to deliver supplemental oxygen. While any dose- or pulse-based oxygen delivery system is set to flow equivalent, dose and continuous flow offer greater consistency and uniformity. The term "pulse equivalent," assumed to be equivalent to continuous flow, is the current way of setting up save regulators. Continuous flow is set to liters per minute.

[0083] Because pulse units do not deliver a continuous supply of oxygen, they cannot be measured in liters per minute. Instead, they are categorized by the size of a single pulse (dose), i.e., the frequency at which the pulse is delivered within a minute, and the duration of the pulse delivery within an inspiratory (breathing) cycle. Another limiting problem with pulsed oxygen concentrators is when a patient attempts more breaths per minute than the unit can produce. When this occurs, the oxygen user will receive smaller pulses, pulses with less oxygen, or no pulses at all. The unit may fail to meet the user's needs if the user is straining and visibly breathless. Using a nasal or oral flow-temperature sensor according to this disclosure, we are able to get closer to the equivalent of a continuous oxygen flow rate because the oxygen is delivered essentially instantly (i.e., within approximately less than 20 milliseconds after the user begins inhaling air, typically within 10–20 milliseconds). Without the inherent delay in pressure sensor methods that trigger oxygen release as previously discussed, there is no need to increase the dose to compensate for the delivery delay.

[0084] Furthermore, with the inhalation start flow-triggered pulsed oxygen delivery according to this disclosure, the user does not need to consider how he or she is breathing due to the increased sensitivity in detecting the start of inspiration—the trigger senses the start of inspiration via a temperature drop in the flow sensor, even when the patient is breathing through their mouth, talking, walking, or eating. Whether the user has large nostrils or is dozing or sleeping in a chair is irrelevant. No training is required—the user simply inserts the cannula into his or her nostril or mouth to experience essentially synchronized oxygen delivery. As mentioned above, conventional pressure flow-triggered pulsed oxygen delivery has a noticeable delay in the “ejection” of delivered oxygen, while the inhalation start flow-triggered oxygen delivery according to this disclosure has virtually no perceptible delay, providing a more natural feel. It essentially releases oxygen as the user inhales, rather than after the user begins to inhale. Moreover, compared to using a conventional chest strain gauge to determine the start of inspiration, the flow sensor of this disclosure triggers the valve to open before any chest movement is detected! This improved synchronization between inhalation initiation and oxygen delivery is more comfortable, efficient, and reliable, and will result in better patient compliance because it actually performs the functions that other types of preservation units only claim to do.

[0085] Other applications of this disclosure are in the field of sleep disorder diagnosis. Much attention has been focused on sleep research to confirm the diagnosis of sleep apnea, which is being diagnosed in sleep laboratories and home sleep studies. Sensing and recording of breathing during sleep can be enhanced by more accurately measuring inspiratory flow. Therefore, the same nasal flow-temperature sensor that can trigger pulsed oxygen delivery can also be used to effectively measure breathing during diagnostic evaluation. Patients with sleep apnea or periodic breathing who are only using supplemental oxygen can also safely use pulsed oxygen delivery. This device now allows patients using C-PAP or Bi-PAP machines to take advantage of the efficiency benefits of pulsed oxygen delivery—delivering supplemental oxygen only during inspiration. This is an improvement over the current method of adding oxygen only to the hose leading to the mask, which provides the least efficient oxygen delivery system considering built-in mask ventilation and accidental mask leaks that occur at night.

[0086] The inspiratory-triggered oxygen delivery according to this disclosure could also liberate walking patients currently limited to a continuous flow rate of 3 liters per minute. Using a portable oxygen concentrator, setting the pulse frequency to 4–6+ liters per minute during sleep is unreliable (“Critical Comparisons of the Clinical Performance of Oxygen-conserving Device”, Am. J. Respir. Crit. Care Med. 15 May 2010; 181(10): 1061–1071; published online 4 February 2010, doi: 10.1164 / rccm.200910-1638OC PMCID: PMC2874449). These high-flow-rate pulse devices claim to provide oxygen to patients during sleep, but most healthcare providers do not consider them to reliably deliver sufficient oxygen to sleeping patients.

[0087] The oxygen delivery triggered by inhalation according to this disclosure can also be applied to "mounted" at the delivery point to a central liquid oxygen system in a hospital or clinic, providing efficiency that does not currently exist.

[0088] Now refer to the attached diagram. Figure 1-3 , Figure 1 This is a block diagram illustrating the components of the housing of a fluid delivery system 100 according to a first exemplary embodiment of the present disclosure. More specifically, Figure 1 A fluid delivery system with a manual bypass valve configuration is shown.

[0089] System 100 includes a housing 120, which may be a shell or similar structure, containing various components for fluid delivery, such that an oxygen (O2) supply 110 can be delivered to a patient 114. The oxygen supply 110 may include an oxygen cylinder 110A, a piped oxygen supply 110B from a hospital or other medical facility, or other equipment for supplying oxygen. Within the housing 120, system 100 includes a pressure regulator 122, which can be connected to the oxygen supply 110 and regulates the pressure at which oxygen is introduced into system 100. The oxygen supply 110 can be removably connected to system 100 using a connector of the pressure regulator 122. The pressure of the oxygen supply may be very high, for example, up to 3000 PSI in some cases, and on the outlet side of the pressure regulator 122, the pressure can be reduced to a desired PSI, for example, 15 PSI in one example. A manual bypass valve 124 receives oxygen from the pressure regulator 122, allowing manual control of oxygen delivery to patient 114. Specifically, the manual bypass valve 124 allows the user to select oxygen delivery along a first path, where pulsed oxygen delivery is controlled by the electronic controller 126, referred to as "pulse mode," or to select oxygen delivery along a second path, which substantially bypasses the controller 126 and delivers oxygen directly or nearly directly to the patient 114, referred to as "bypass mode."

[0090] When in pulse mode, i.e., when the manual bypass valve 124 is positioned to deliver oxygen to a patient controlled by the controller 126, oxygen is directed to valve 128, which can be a three-way piezoelectric valve or another type of valve. When valve 128 is de-energized, it prevents oxygen flow through it, while when energized or activated, it opens one or more valve ports to allow oxygen flow. The oxygen supply to valve 128 is also in fluid communication with an oxygen pressure sensor 130 connected to the controller 126, allowing the oxygen pressure to be sensed. The output of valve 128 is connected to the oxygen output 132 of system 100 leading to patient 114. Figure 1 As shown, oxygen delivery to a patient may include various tubes with a nasal cannula 143, which may be placed near the patient's nose, but other delivery systems may also be used, including masks, suffocating devices, etc.

[0091] Controller 126 also includes electronic control components, such as microcontrollers, circuits, input and output devices, or other components for the activation and use of control system 100, relative to... Figure 3The following is a detailed description. Generally, controller 126 communicates with valve 128, oxygen pressure sensor 130, indicator device 134, ambient air supply 136, and power supply 138. Ambient air supply 136 may include a port in housing 120 that draws in ambient air and passes it through airflow sensor 140. Airflow sensor 140 communicates with nasal cannula 143 and provides a reading of ambient air flow to a processor or microcontroller and senses the onset of inspiration, as described below. The output of ambient air supply 136 may be delivered to patient 114 using tubing and cannulas, masks, suffocation devices, or other delivery assemblies, or via ambient air outlet 142 and a dual-lumen cannula, as described below. Figure 2 As shown.

[0092] The indicator device 134 may include various indicator types, such as a keypad with visual indicators in one example. Other types of indicators may also be used. The visual indicators of the indicator device 134 may include visual indicators for operations including standby, pulse control, sensitivity, bypass or pulse delivery, power level, and alarm. Typically, the indicator device 134 may be substantially integrated into the housing 120, but it may also be a completely or partially independent device. The power supply 138 may include one or more different power supply devices, such as hardwired devices, such as 115 / 230V AC power, user-replaceable batteries, rechargeable user-replaceable batteries, or replaceable or non-replaceable internal rechargeable batteries. Naturally, the power supply 138 may include combinations of these or other power supplies to ensure continued operation of the operating system 100 in the event of a power failure. The controller 126 may include additional components, such as an audible alarm system 144, to provide audible alarms to patients or other users as needed. Figure 2 Let's have a discussion.

[0093] During operation, the intubation tube or other delivery device is positioned close to the mouth or nose of patient 114. System 100 receives oxygen from oxygen supply 110 and ambient air via ambient air supply 136. When the patient inhales, negative pressure is applied to the intubation tube housed at oxygen output 132 and / or ambient air input 136. When in pulse mode, controller 126 is activated and controls the delivery of pulsed oxygen to the patient. Activation of controller 126 causes controller 126 to energize piezoelectric valve 128, thereby opening a path for oxygen to flow from oxygen supply 110 through pressure regulator 122, bypass valve 124, and to patient 114. Controller 126 can control a specific flow rate of oxygen to patient 114, for example, by controlling the oxygen pulse length, pulse frequency, or other pulse characteristics that allow oxygen to pass through valve 128, or by controlling the sensitivity of activation or one or more components of system 100. During controlled pulsed oxygen delivery, patient 114 can continue to receive ambient air via ambient air input 136.

[0094] The controller 126 can be manually activated, for example, by a button or switch, or more preferably, according to this disclosure, automatically activated by a sensing signal indicating the start of inhalation. In one example, the controller 126 can be activated by sensing a temperature change that occurs when a patient begins to inhale. In this example, a flow sensor in the form of a thermistor 140, located in the path of the ambient air supply 136, is heated to a temperature above ambient, typically 10 to 20°C above ambient. When the user inhales, the inline thermistor detects a temperature drop due to the ambient airflow passing through the heated thermistor 140. When this temperature drop is detected, an activation signal is sent to valve 128 to release oxygen. Alternatively, the air in the path of the ambient air supply 136 located near the thermistor 140 can be heated to a temperature above ambient. When the user inhales, the thermistor can be used to detect the temperature rise as the ambient air supply flows through the thermistor 140, which in turn can be used to send an activation signal. In a preferred embodiment, the thermistor is configured to measure temperature changes in either direction, i.e., to measure temperature changes during inhalation to trigger oxygen delivery, and to measure temperature changes during exhalation to trigger cessation of oxygen delivery. Sensing the start of exhalation also allows the system to provide a single trigger for each inhalation. After inhalation is sensed and a fluid pulse is triggered, the system can prevent re-triggering of the same inhalation by suppressing any triggering until exhalation is sensed.

[0095] To protect the flow sensor from the high-pressure oxygen flow, valve 128 includes dual-actuator piezoelectric valves 200 and 202. Piezoelectric valve 200 is inlined between the supplemental oxygen source 110 and the flow sensor plate 140, while piezoelectric valve 202 is connected to the sensor plate 140 on one side and opens to ambient air on the other. Isolating the flow sensor from the high-pressure oxygen flow allows the use of a highly sensitive flow sensor, which in turn allows us to sense inhalation substantially immediately at the start, thus allowing us to trigger the oxygen pulse at the most appropriate time without waste. Existing reservoirs sense and deliver airflow from the same conduit and cannot sense inhalation substantially immediately at the start. Furthermore, by isolating the flow sensor, we eliminate any flow contamination from the user's exhaled air.

[0096] So far, the description of the operation of system 100 has pertained to the system being in pulse mode, i.e., oxygen delivery is controlled by electronic controller 126. However, using manual bypass valve 124, the user can switch system 100 from pulse mode to bypass mode to deliver oxygen directly to patient 114. Figure 1 As shown, in bypass mode, the oxygen supply 110 from pressure regulator 122 can be directed directly or nearly directly to oxygen outlet 132 via manual bypass valve 124, as oxygen can be delivered through one or more shunt connectors. Therefore, in bypass mode, oxygen is delivered to patient 114 without pulse control by controller 126. Using bypass valve 124, the user can control the system 100 to the desired operating mode as needed, depending on the patient or the intended use of the system 100.

[0097] Figure 3 Accordingly, a third exemplary embodiment based on this disclosure is shown. Figure 1-2 A block diagram of the electrical block diagram of the controller 126 of the fluid delivery systems 100 and 102. (See diagram below.) Figure 3 As shown, controller 126 includes various controller circuits and processing modules that communicate with components of the fluid delivery system. All components can communicate with microcontroller 150, which can receive signals and process data from each component and control processing functions.

[0098] Microcontroller 150 is connected to oxygen sensor 130 or an oxygen transducer resistor bridge, whereby the signal from oxygen sensor 130 is amplified by a bridge signal amplifier and then input to microcontroller 150 via an ADC connection. An optional secondary oscillator may be provided to microcontroller 150. An internal factory CAL switch or jumper may be connected to microcontroller 150 via a CAL switch circuit. The temperature of ambient air supply 136 sensed by thermistor 140 may be connected to microcontroller 150 via flow sensor circuit 152. Within flow sensor circuit 152, heater control and one or more heater drivers may be used to heat thermistor 140 and / or the ambient supply around it, and the flow signal from thermistor 140 is received back in flow sensor circuit 152. This signal may be processed by offset adjustment and / or span adjustment and then amplified before being transmitted to microcontroller 150.

[0099] The piezoelectric valve 128 receives control signals from the oxygen port piezoelectric valve driver 154 and the flow sensor port piezoelectric valve driver 156, both connected to the microcontroller 150. The oxygen port piezoelectric valve driver 154 has a piezoelectric driver DC-DC converter, a voltage selector circuit, and FET switch control connected to a power supply and on / off signal. The flow sensor port piezoelectric valve driver 156 has a second piezoelectric driver DC-DC converter, a voltage selector circuit, and FET switch control. During operation of either driver 154 or 156, a signal from the voltage selector circuit is provided to the FB circuit, which provides voltage feedback to the piezoelectric driver DC-DC converter. The signal received from the microcontroller by the FET switch control is transmitted to the corresponding connection or drain switch of each driver 154 or 156. The resulting signals from the oxygen switch of the oxygen port driver 154 and the flow sensor switch of the flow sensor driver 156 are transmitted to the piezoelectric valve 128 to control energization and activation.

[0100] Indicator device 134 can be connected to microcontroller 150 via one or more keypad key sensing and LED driver circuitry. Similarly, audible alarm system 144 can be connected to microcontroller 150 using a buzzer driver. Power supply 138, including hardwired power or battery power, can be connected to microcontroller 150 using a power selector that controls power distribution. Various voltage regulators and converters can be used directly or via, for example... Figure 3 The microcontroller 150 shown facilitates the power supply to various circuits and components of the fluid delivery system. Additional power supply components may also be included, such as power input protection circuitry, charging circuitry, battery voltage monitoring, or others. The microcontroller 150 may also have an ADC test circuit 158 ​​connected thereto.

[0101] Further details of this disclosure can be found in [link to disclosure]. Figure 4It is a schematic diagram illustrating the operating algorithm of the supplemental oxygen delivery system of this disclosure, and explaining how the system prevents re-triggering on the same inhalation by suppressing any further triggering until exhalation is sensed after sensing inhalation and triggering a fluid pulse.

[0102] Figure 5 Table I reports the response time of the temperature sensor according to this disclosure in triggering supplemental oxygen flow after the patient's inhalation, compared with the response time of conventional pressure sensors (OM-700 Chad Lotus therapeutic oxygen conservator and CTOX-MN02 SmartDose oxygen conservator) in triggering supplemental oxygen flow after the inhalation. In the tests, the temperature sensor flow sensor according to this disclosure was found to be 40 times more sensitive than conventional prior art pressure flow sensors.

[0103] Figure 6 A flowchart of a gas delivery method according to a preferred embodiment of this disclosure is shown. More specifically, we have found that by increasing the delivery of supplemental oxygen flow from the moment of sensed inhalation, supplemental oxygen can be better preserved, i.e., there is little or no loss of oxygen through the mast or cannula, and the user is more comfortable. This is due to the fact that opening a fully metered supplemental oxygen flow from a pressurized source, as in the conventional manner, would result in oxygen flowing into the user at an initial rate far exceeding what the user can tolerate. That is, due to the natural expansion of the lungs during breathing, the user cannot inhale the full target flow of supplemental oxygen quickly enough to achieve comfort and efficiency. Therefore, instead of overwhelming the wearer with the full target flow of supplemental oxygen, the supplemental oxygen flow is increased at the moment of detected inhalation, substantially in harmony with the user's breathing pattern. Typically, the delivery of supplemental oxygen is increased from an initial flow of 15-40%, preferably 20-35%, more preferably 33% at triggering to 100% of the target flow at the user's maximum inspiratory volume, and then closed and paused at or before the user begins to exhale. For example, assuming a target oxygen flow rate of 16 liters per minute, the initial oxygen flow rate can be set to 5 or 6 liters per minute at the start of inhalation, increasing to 16 liters per minute based on the user's inhalation, and then shut off when the flow sensor senses that inhalation has stopped or slowed down. This is in Figure 7 This was explained in the text.

[0104] Although this disclosure has been described in detail with reference to certain embodiments, those skilled in the art will understand that this disclosure can be practiced in ways other than those described for illustrative and non-limiting purposes. For example, the system described above can be inserted into a conventional fixed-flow regulator or a conventional hospital wall-mounted unit regulator and converted into a "smart regulator." The system can also be built into a C-PAP mask or modified as an additional feature of a C-PAP mask. The system can also be used to control the delivery of therapeutic gases (e.g., nitric oxide or anesthetic gases) or to regulate the flow of supplemental oxygen or breathing gases for mountaineering and water breathing apparatus applications, fire and rescue protective equipment, spacesuit applications, etc., which may use sealed helmets instead of nasal or oral cannulas or masks. Thus, as used herein, nasal and oral cannulas are intended to also include masks, sealed helmets, etc. Other variations are also possible. Therefore, the scope of the appended claims should not be limited to the description of the embodiments contained herein.

Claims

1. A fluid delivery system for controlling the delivery of supplemental fluid oxygen to humans or animals, comprising: At least one source of the fluid; At least one valve assembly connected to the at least one source of the fluid, wherein the at least one valve assembly is configured to allow the fluid from the at least one source to flow during the inhalation of the person or animal; The outlet end is selected from a nasal cannula, oral cannula, mask, and helmet that are in fluid communication with at least one valve assembly; A flow sensor for triggering fluid delivery in response to inhalation by the person or animal, wherein the flow sensor includes a temperature sensor in the form of a thermistor. The flow sensor is in fluid communication with the outlet and is located upstream of the outlet. The temperature sensor is configured to detect temperature changes that indicate the onset of inhalation in the person or animal; and The flow sensor is configured to detect the onset of inhalation and exhalation by directional changes in temperature, and the system further includes a first heater located upstream of the temperature sensor and a second heater located downstream of the temperature sensor.

2. The fluid delivery system of claim 1, wherein One or more of the following characteristics: (a) Further includes a power supply configured to operate at least one valve assembly; (b) wherein the flow sensor is located in a pipe connecting the outlet end and at least one source of the fluid; (c) The fluid being transported is selected from supplemental oxygen, therapeutic gases, and anesthetic gases; (d) It also includes electronic circuitry for controlling at least one valve assembly based on a signal from a flow sensor; (e) Further includes electronic circuitry, the electronic circuitry including a triggering mechanism for initiating the release of the fluid through the at least one valve assembly; (f) wherein the temperature sensor is configured to detect a temperature change that indicates the onset of inhalation in the person or animal; and (g) wherein the first heater and the second heater are configured to heat the flow sensor to 10°C to 20°C above the ambient temperature.

3. An apparatus for storing supplemental fluid oxygen supplied from a fluid supply to a person or animal, comprising: A fluid reservoir controller connected between a fluid supply and an outlet, the outlet being selected from a nasal cannula, an oral cannula, a face mask, and a helmet, wherein the controller includes at least one valve that is selectively triggered to deliver the fluid to the outlet; A flow sensor configured to sense inhalation in a human or animal, wherein the flow sensor includes a temperature sensor in the form of a thermistor, the temperature sensor being configured to detect a temperature change that indicates the onset of inhalation in the human or animal. A trigger mechanism, which communicates with the flow sensor to activate the fluid reservoir controller, wherein the flow sensor is in communication with the outlet fluid, and The temperature sensor is configured to detect the onset of inhalation and exhalation by directional changes in temperature, and the system further includes a first heater located upstream of the temperature sensor and a second heater located downstream of the temperature sensor.

4. The apparatus of claim 3, wherein One or more of the following characteristics: (a) wherein the flow sensor and the triggering mechanism are located far apart from each other, and wherein the flow sensor and the triggering mechanism are connected by wired or wireless communication; (b) Wherein the fluid supply source includes oxygen, therapeutic gas or anesthetic gas; (c) It also includes electronic circuitry for controlling at least one valve based on a signal from a flow sensor; (d) wherein the temperature sensor is configured to detect a temperature change that indicates the onset of inhalation in the person or animal; and (e) wherein the first heater and the second heater are configured to heat the flow sensor to 10°C to 20°C above the ambient temperature.

5. A fluid delivery system for controlling the delivery of fluid to a person or animal, comprising: At least one source of the fluid; At least one valve assembly connected to the at least one source of the fluid, wherein the at least one valve assembly is configured to allow flow of the fluid from the at least one source during inhalation by the person or animal; The outlet end is selected from a nasal cannula, oral cannula, mask, and helmet that are in fluid communication with at least one valve assembly; A flow sensor is used to trigger fluid delivery in response to the inhalation of the person or animal, and A heater configured to heat a flow sensor or the fluid upstream of a flow sensor; The flow sensor is in fluid communication with and upstream of the outlet, isolated from the fluid from at least one source, and includes a MEMS thermal flow sensor or a MEMS thermal mass flow sensor configured to detect directional changes in the temperature of the fluid that indicate the onset of inhalation or exhalation in the person or animal.

6. The fluid delivery system of claim 5, wherein One or more of the following characteristics: (a) Further includes a power supply configured to operate at least one valve assembly; (b) wherein the flow sensor is located near the outlet or in a pipe connecting the outlet and at least one source of the fluid; (c) The fluids being transported include supplemental oxygen, therapeutic gases, or anesthetic gases; (d) Further includes electronic circuitry for controlling at least one valve assembly based on a signal from a flow sensor; (e) Further includes electronic circuitry, wherein the electronic circuitry includes a triggering mechanism for initiating the release of the fluid through the at least one valve assembly; (f) wherein the heater is configured to heat the fluid upstream of the flow sensor to 10-20°C above ambient temperature; and (g) wherein the flow sensor is isolated from at least one source of the fluid via a piezoelectric actuator valve.

7. An apparatus for storing fluid supplied from a fluid supply to a person or animal, comprising: A fluid reservoir controller connected between a fluid supply and an outlet, the outlet being selected from a nasal cannula, an oral cannula, a face mask, and a helmet, wherein the controller includes at least one valve that is selectively triggered to deliver the fluid to the outlet; A flow sensor configured to sense the inhalation of a human or animal; Heater, configured as a heating flow sensor; and A triggering mechanism, which communicates with the flow sensor to activate the fluid reservoir controller, wherein the flow sensor is in fluid communication with the outlet end and isolated from the fluid flow from the fluid supply, and includes a MEMS thermal flow sensor or a MEMS thermal mass flow sensor configured to detect a directional change in the temperature of the fluid flow that indicates the start of inhalation or exhalation of the person or animal.

8. The apparatus of claim 7, wherein One or more of the following characteristics: (a) wherein the flow sensor and the triggering mechanism are located far apart from each other, and wherein the flow sensor and the triggering mechanism are connected by wired or wireless communication; (b) The fluid supply includes oxygen, therapeutic gas, or anesthetic gas; (c) Further includes electronic circuitry for controlling at least one valve based on a signal from a flow sensor; and (d) The flow sensor is isolated from the fluid supply via a piezoelectric actuator valve.

9. A fluid delivery system for controlling the delivery of fluid to a person or animal, comprising: At least one source of the fluid; At least one valve assembly connected to the at least one source of the fluid, wherein the at least one valve assembly is configured to allow the fluid to flow from the at least one source through a conduit during the inhalation of the person or animal; The outlet end includes a nasal cannula, an oral cannula, a mask, and a helmet in fluid communication with at least one valve assembly; A flow sensor for triggering fluid delivery in response to the breathing of the human or animal, wherein the flow sensor includes two MEMS thermal flow sensors or two MEMS thermal mass flow sensors having a heater configured to heat the fluid flow located between the two MEMS thermal flow sensors or two MEMS thermal mass flow sensors. The flow sensor is configured to detect fluid flow that indicates the start or stop of the person's or animal's breathing by detecting directional changes in the temperature of the fluid flow.

10. The fluid delivery system of claim 9, wherein One or more of the following characteristics: (a) Further includes a power supply configured to operate at least one valve assembly; (b) wherein the flow sensor is located in a pipe connecting the outlet end and at least one source of the fluid; (c) The fluids being transported include supplemental oxygen, therapeutic gases, or anesthetic gases; (d) Further includes electronic circuitry for controlling at least one valve assembly based on signals from a MEMS flow sensor; and (e) Further includes electronic circuitry, wherein the electronic circuitry includes a triggering mechanism for initiating the release of the fluid through the at least one valve assembly.

11. An apparatus for storing fluid supplied from a fluid supply to a person or animal, comprising: A fluid reservoir controller is connected via a conduit between a fluid supply and an outlet, the outlet being selected from a nasal cannula, an oral cannula, a face mask, and a helmet, wherein the controller includes at least one valve that is selectively triggered to deliver the fluid to the outlet; A flow sensor configured to sense the onset of inhalation or exhalation of the person or animal; The flow sensor includes two MEMS thermal flow sensors or two MEMS thermal mass flow sensors, which have a heater configured to heat the fluid flow between the two MEMS thermal flow sensors or two MEMS mass flow sensors, wherein the flow sensor is configured to detect directional changes in the temperature of the fluid flow. and A triggering mechanism, which communicates with the flow sensor to activate the preserver controller, wherein the flow sensor is positioned in fluid communication with the outlet and is configured to detect the flow rate of the fluid indicating the start of inhalation or exhalation of the person or animal.

12. The apparatus of claim 11, wherein One or more of the following characteristics: (a) wherein the flow sensor and the triggering mechanism are located far apart from each other, and wherein the flow sensor and the triggering mechanism are connected by wired or wireless communication; (b) The fluid supply includes oxygen, therapeutic gas, or anesthetic gas; (c) also includes electronic circuitry for controlling at least one valve based on a signal from a flow sensor; and (d) wherein the flow sensor is configured to detect temperature changes that indicate the start of inhalation in the person or animal.

13. A fluid delivery system for controlling the delivery of fluid to a person or animal, comprising: At least one source of the fluid; At least one valve assembly connected to the at least one source of the fluid, wherein the at least one valve assembly is configured to allow flow of the fluid from the at least one source during inhalation by the person or animal; The outlet end is selected from a nasal cannula, oral cannula, mask, and helmet that are in fluid communication with at least one valve assembly; A flow sensor is used to trigger fluid delivery in response to the inhalation of the person or animal, and A heater configured to heat the flow sensor or fluid upstream of the flow sensor to a temperature above ambient. The flow sensor is in fluid communication with the outlet and is located upstream of the outlet, and includes a thermal sensor configured to detect temperature changes that indicate the onset of inhalation in the person or animal. At least one of the valve components is configured to initiate fluid flow delivery upon triggering when a person or animal inhales, and to gradually increase the initial flow rate from 15-40% of the initial flow rate to 100% of the fluid flow delivery, and then close or pause the fluid flow delivery at or before the person or animal begins to exhale, in coordination with the breathing pattern of the person or animal.

14. The fluid transport system according to claim 13, characterized in that... One or more of the following: (a) Further includes a power supply configured to operate at least one valve assembly; (b) wherein the flow sensor is located in or near the outlet, or in a pipe connecting the outlet and at least one source of the fluid; (c) The fluids being transported include supplemental oxygen, therapeutic gases, or anesthetic gases; (d) Further includes electronic circuitry for controlling at least one valve assembly based on a signal from a flow sensor, wherein the electronic circuitry includes a triggering mechanism for initiating the release of fluid through the at least one valve assembly; (e) At least one of the valve assemblies is configured to gradually deliver fluid flow from an initial flow rate of 20-35% at trigger to 100% of the inspiratory capacity of a human or animal; (f) wherein the thermal sensor is configured to detect the onset of inhalation and the onset of exhalation by means of directional changes in temperature, and wherein the system includes a heater located upstream of the temperature sensor; (g) wherein the thermal sensor is configured to detect the onset of inhalation and the onset of exhalation by directional changes in temperature, and wherein the system includes heaters located upstream and downstream of the temperature sensor; and (h) wherein the flow sensor is isolated from at least one source of the fluid via a piezoelectric actuator valve.

15. An apparatus for storing fluid supplied from a fluid supply to a person or animal, comprising: A fluid reservoir controller connected between a fluid supply and an outlet, the outlet being selected from a nasal cannula, an oral cannula, a mask, or a helmet, wherein the controller includes at least one valve that is selectively triggered to deliver the fluid to the outlet; A flow sensor configured to sense the inhalation of a human or animal; A heater configured to heat the flow sensor or the fluid upstream of the flow sensor to above ambient temperature; A trigger mechanism, which communicates with the flow sensor to activate the fluid reservoir controller, wherein the flow sensor is in contact with the outlet fluid and includes a temperature sensor configured to detect a temperature change indicating the onset of inhalation in the person or animal. At least one of the valve components is configured to initiate fluid flow delivery upon triggering when a person or animal inhales, and to gradually increase the initial flow rate from 15-40% of the initial flow rate to 100% of the fluid flow delivery, and then close or pause the fluid flow delivery at or before the person or animal begins to exhale, in coordination with the breathing pattern of the person or animal.

16. The apparatus according to claim 15, characterized by one or more of the following features: (a) wherein the flow sensor and the triggering mechanism are located far apart from each other, and wherein the flow sensor and the triggering mechanism are connected by wired or wireless communication; (b) Wherein the fluid supply source includes oxygen, therapeutic gas or anesthetic gas; (c) Further includes electronic circuitry for controlling at least one valve assembly based on a signal from a flow sensor; (d) At least one of the valve assemblies is configured to gradually increase the fluid flow from 20-35% of the initial flow rate at trigger to 100% of the inspiratory capacity of a human or animal; (e) wherein the temperature sensor is configured to detect the onset of inhalation and the onset of exhalation by means of directional changes in temperature; (f) wherein the device includes a heater located downstream of the temperature sensor; and (g) Wherein the flow sensor is isolated from the fluid supply via a piezoelectric actuator valve.

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