The present invention relates generally to medical devices and methods of use, and more particularly to systems and methods for treating bleeding in a body cavity such as intra-nasal bleeding (epistaxis), bleeding diverticula in the colon, upper gastrointestinal bleeding in the stomach or duodenum, bleeding in the esophagus, bleeding in the uterus, and bleeding in the urethra.
Tamponade treatment for epistaxis is painful and traumatic to the nasal mucosa and may necessitate hospitalization for several days. A posterior pack is placed to occlude the choanal arch and, in conjunction with an anterior nasal pack, provide hemostasis. Posterior packing can be accomplished with gauze, a Foley catheter, a nasal sponge/tampon, or an inflatable nasal balloon catheter. Posterior packing is very uncomfortable and may necessitate procedural sedation. Hot water irrigation was introduced as a treatment of epistaxis 140 years ago. However, its use was abandoned by the middle of the 20th century because many patients were at risk of aspirating water and the development of nasal tampons and advances in lighting and endoscopic techniques replaced the practice of hot water irrigation.
Hot water irrigation treatment for posterior epistaxis involves running hot water into the bleeding nose cavity and the treatment is successful in many cases. The therapeutic temperature of the hot water is from 46 degrees Celsius to 52 degrees Celsius. Water temperatures below 46 degrees Celsius have no effect, only light changes occur at 46 degrees Celsius and 47 degrees Celsius, and the best effect occurs between 48 degrees Celsius and 52 degrees Celsius as vasodilation, edema of the mucosa, and subsequent narrowing of the intranasal lumen occur in this temperature range. Severe changes, including epithelial necrosis, occur when the treatment temperature is higher than 52 degrees Celsius. The hemostatic effect of hot water treatment for epistaxis may be caused by: (1) edema and narrowing of the intranasal lumen, (2) vasodilation of the mucosal vessels, (3) cleaning blood coagulates from the nasal passageway, and (4) elevated temperatures accelerating the clotting cascade. In a study conducted by Stangerup et al in 1999, the treatment proved to be effective, less painful, less traumatic, and required a shorter hospital stay than tamponade treatment.
The study performed by Stangerup et al, included a thermometer (0 degrees Celsius-100 degrees Celsius), a thermo-bucket filled with fresh hot water (50 degrees Celsius) from the hot water tap, a 10-mL and a 100-mL syringe, and the catheter. The patient was instructed to sit with the head flexed and a catheter was introduced via the bleeding nasal cavity. The balloon was then filled with 10 ml, of hot water, and the catheter was pulled back so that the balloon on the end of the catheter sealed the posterior choana of the bleeding nasal cavity. The nasal cavity was irrigated forcefully via the catheter with 500 mL of hot water using a 100-mL syringe. After irrigation, the catheter was removed and the patient was observed for 15 minutes.
Although the hot water irrigation treatment used by Stangerup et al was effective in reducing the likelihood of aspirating water by blocking the choana with a balloon, it is not commonly used because it is inconvenient, inconsistent, and time consuming for the care giver.
Benign Prostatic Hyperplasia (BPH), or prostate gland enlargement, is one of the most common medical conditions that affect men, particularly elderly men. It has been reported that, in the United States, more than half of all men have histopathologic evidence of BPH by age 60 and, by age 85, approximately 9 out of 10 men suffer from the condition. Moreover, the incidence and prevalence of BPH are expected to increase as the average age of the population in developed countries increases.
Established minimally invasive procedures for treating BPH symptoms include Transurethral Microwave Thermotherapy (TUMT), Transurethral Needle Ablation (TUNA), and Interstitial Laser Coagulation (ILC). Other newer procedures include steam induced coagulation necrosis of prostate tissue and the use of pressurized water to remove prostate tissue. And certain implants are being used to open the prostatic urethra.
In Transurethral Microwave Thermotherapy (TUMT), microwave energy is used to generate heat that destroys hyperplastic prostate tissue. This procedure is performed under local anesthesia. In this procedure, a microwave antenna is inserted in the urethra. A rectal thermosensing unit is inserted into the rectum to measure rectal temperature. Rectal temperature measurements are used to prevent overheating of the anatomical region. The microwave antenna is then used to deliver microwaves to lateral lobes of the prostate gland. The microwaves are absorbed as they pass through prostate tissue. This generates heat which in turn destroys the prostate tissue. The destruction of prostate tissue reduces the degree of squeezing of the urethra by the prostate gland thus reducing the severity of BPH symptoms.
Another example of a minimally invasive procedure for treating BPH symptoms is Transurethral Needle Ablation (TUNA). In this procedure, heat induced coagulation necrosis of prostate tissue regions causes the prostate gland to shrink. It is performed using local anesthetic and intravenous or oral sedation. In this procedure, a delivery catheter is inserted into the urethra. The delivery catheter comprises two radio-frequency needles that emerge at an angle of 90 degrees from the delivery catheter. The two radio-frequency needles are aligned are at an angle of 40 degrees to each other so that they penetrate the lateral lobes of the prostate. A radio-frequency current is delivered through the radio-frequency needles to heat the tissue of the lateral lobes to 70-100 degrees Celsius at a radio-frequency power of approximately 456 KHz for approximately 4 minutes per lesion. This creates coagulation defects in the lateral lobes. The coagulation defects cause shrinkage of prostatic tissue, which, in turn, reduces the degree of squeezing of the urethra by the prostate gland thus reducing the severity of BPH symptoms.
Another example of a minimally invasive procedure for treating BPH symptoms is Interstitial Laser Coagulation (ILC), In this procedure, laser induced necrosis of prostate tissue regions causes the prostate gland to shrink. It is performed using regional anesthesia, spinal or epidural anesthesia or local anesthesia (periprostatic block). In this procedure, a cystoscope sheath is inserted into the urethra and the region of the urethra surrounded by the prostate gland is inspected. A laser fiber is inserted into the urethra. The laser fiber has a sharp distal tip to facilitate the penetration of the laser scope into prostatic tissue. The distal tip of the laser fiber has a distal-diffusing region that distributes laser energy along the terminal 3 mm of the laser fiber. The distal tip is inserted into the middle lobe of the prostate gland and laser energy is delivered through the distal tip for a desired time. This heats the middle lobe and causes laser induced necrosis of the tissue around the distal tip. Thereafter, the distal tip is withdrawn from the middle lobe. The same procedure of inserting the distal tip into a lobe and delivering laser energy is repeated with the lateral lobes. This causes tissue necrosis in several regions of the prostate gland which in turn causes the prostate gland to shrink. Shrinkage of the prostate gland reduces the degree of squeezing of the urethra by the prostate thus reducing the severity of BPH symptoms.
Although some of these methods can be effective at alleviating symptoms of BPH, these methods frequently create bleeding injury within the prostatic urethra. The bleeding injury can be a result of the intentional destruction, dissection, or penetration of tissue, or it can be incidental to the treatment, such as when a minimally invasive device injures tissue along the prostatic urethra during insertion or removal of the device. In any case, the bleeding injury in the prostatic urethra is unpleasant for the patient and typically requires several days to resolve. The tissue damage frequently results in hematuria (blood in urine) and may require the patient to wear a catheter to drain urine from the bladder for a period of time adequate to allow the urethra to heal.
Methods and devices are described herein to provide convenience, reduce time, and improve patient comfort.
A method for treating bleeding in the urethra is disclosed herein, wherein an irrigant in the temperature range of 46 degrees Celsius to 52 degrees Celsius is motivated to lavage a patient's urethra via a catheter wherein the irrigant flows to the urethra via the catheter. The method includes an aspect wherein the irrigant flows from the urethra via the catheter. The method includes an aspect wherein the irrigant flow rate is between 2 cc/second and 12 cc/second.
A system for treating bleeding in a urethra is disclosed herein. The system includes an irrigant source, a heating apparatus connected to the irrigant source, wherein the heating apparatus is configured to heat an irrigant as the irrigant flows through the heating apparatus, and a treatment catheter having an irrigant outlet and an irrigant inlet located at a distal portion of a catheter body of the treatment catheter, wherein the irrigant outlet is located farther distally on the catheter body than the irrigant inlet. Alternatively, the positions of the inlet and outlets may be reversed. The system includes an aspect wherein the irrigant flow rate is between 2 cc/second and 12 cc/second. The system includes an aspect wherein the irrigant temperature is between 46 degrees Celsius and 52 degrees Celsius. The system includes an aspect wherein the system includes a pump. The system includes an aspect wherein the heating apparatus includes a heating element that heats the irrigant via a volumetric heating method, such as via the application of radio-frequency energy.
A method for treating a bleeding nasal passageway is disclosed herein, wherein an irrigant in the temperature range of 46 degrees Celsius to 52 degrees Celsius is motivated to flow into the first nasal passageway then past the posterior septal margin and through the contralateral nasal passageway and out the contralateral rare for a sufficient period of time and volume to cause hemostasis of the bleeding nasal passageway. In some aspects of the method, the irrigant flow rate is between 2 cc/second and 12 cc/second.
A device for treating a bleeding nasal passageway is disclosed herein, wherein the device incudes a reservoir capable of holding or receiving a irrigant, a heating system, temperature controller, irrigant pump, and nasal interface wherein the irrigant is heated by the irrigant heating system to a temperature in the range of 48 degrees Celsius to 52 degrees Celsius and the irrigant is motivated by the irrigant pump to flow into a first nasal passageway and past a bleeding site in the nasal passageway or a contralateral nasal passageway. In some aspects of the method, the irrigant flow rate is between 2 cc/second and 12 cc/second.
A method for treating gastric bleeding is disclosed herein, wherein a irrigant in the temperature range of 46 degrees Celsius to 52 degrees Celsius is motivated to lavage a patient's stomach via a conduit inserted into the stomach such as a naso-gastric tube wherein the stomach has one or more bleeding sites and the irrigant flows out of the patient's stomach and flows or is drawn out of the stomach by suction into a collection receptacle. The conduit may contain a single lumen or preferably a plurality of lumens to enable continuous flow into and out of the stomach.
A device for treating gastric bleeding is disclosed herein, wherein the device is comprised of a reservoir capable of holding or receiving a irrigant, a heating system, temperature controller, irrigant pump, and a conduit capable of being placed in the stomach such as a naso-gastric tube wherein the irrigant is heated by the irrigant heating system to a temperature in the range of 46 degrees Celsius to 52 degrees Celsius and the irrigant is motivated by the irrigant pump to lavage a patient's bleeding stomach and the irrigant exits the bleeding patient's stomach and flows through a conduit and into a collection receptacle. The conduit may contain a single lumen or preferably a plurality of lumens to enable continuous flow into and out of the stomach.
Other features and advantages of embodiments of the present system and method will become apparent from the following description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, certain principles of the system and method.
There is need for improved methods and apparatus for treating a bleeding body cavity, in particular a bleeding nose, stomach, or urethra. The present invention relates to apparatus and methods for arresting bleeding in a body cavity such as intra-nasal bleeding (epistaxis), bleeding diverticula in the colon, upper gastrointestinal bleeding in the stomach or duodenum, bleeding in the esophagus, and bleeding in the uterus. The present invention provides methods and devices for increasing the temperature of body tissues to the proper temperature range that will cause hemostasis. The present invention provides devices and methods for arresting bleeding in a body cavity or passageway.
The size, dimensions, and characteristics of the invention herein may be altered according to the treatment site or body cavity. The device is not limited to any particular body cavity or treatment location.
Irrigant may refer to any number of irrigants including water, saline, or water with solutions such as sodium chloride and sodium bicarbonate. In some embodiments, the actual composition of the irrigant is less important than the temperature and flow rate, as the irrigant acts to raise the temperature of the mucosa for a period of time. Thus, to the extent an irrigant is specified in an embodiment, such as when the use of water is described, it is understood that other irrigants may also be used in such an embodiment.
One method for causing hemostasis is to irrigate the bleeding site with irrigant at a temperature in the range of 46 degrees Celsius to 52 degrees Celsius. In the context of epistaxis, irrigation occurs by causing the irrigant to flow through the nare and nasal passageway toward the choana, around the posterior septal margin, then through the contralateral nasal passageway away from the choana before it exits the contralateral nare. The irrigant may flow toward or away from the choana in the bleeding nasal passageway with only minor differences in efficacy.
Hot water irrigation for treating epistaxis involves motivating irrigant at the therapeutic temperature into the first nare such that it flows through nasal passageway, around the septum and through the second nasal passageway before exiting the second nare. The use of hot water irrigation was almost completely discontinued several decades ago because many patients were at risk for aspirating water into the lungs.
Hot water irrigation for either the nasal passageway or stomach with 48 degrees Celsius to 52 degrees Celsius water may be uncomfortable for the patient unless the amount of heat delivered to the nasal passageway(s) or stomach is controlled. This may be done by conditioning to the high temperature by starting at a lower, more tolerable temperature then increasing the temperature at a tolerable rate until the therapeutic temperature range is met and maintained for the prescribed time. Alternatively, the patient's ability to tolerate the therapy may be improved by controlling the irrigant flow rate through the nasal passageway or stomach. Higher flow rates deliver more heat energy to the tissue whereas lower flow rates deliver less heat energy. Anatomical variations between patients may also necessitate adjustments in the flow rate.
Various options for controlling the flow rate of irrigant include controlling the irrigant pressure, controlling the volumetric change of irrigant at the reservoir, flow rate sensors, or controlling the volume of irrigant through a pumping mechanism.
When treating epistaxis, it is desirable to flush any blood clots out of the nasal passageway. This may be performed by directing the flow of irrigant in to the nonbleeding (contralateral) nasal passageway and allowing it to flow out of the bleeding side. After the bleeding nasal passageway is cleaned of clots and other matter, it may be desirable to reverse the irrigant direction to flow in to the bleeding passageway. This exposes the bleeding mucosa to irrigant in the therapeutic temperature range without a reduction in the irrigant temperature as heat is lost while the irrigant passes through the nonbleeding, contralateral nasal passageway.
Patient comfort may be improved by initially irrigating the nasal passageway at a temperature below the therapeutic minimum of 46 degrees Celsius or the preferential therapeutic minimum 48 degrees Celsius then increasing the temperature to the therapeutic range. Therefore, a device to automatically adjust the temperature for patient comfort by starting lavage at a comfortable temperature, then increasing and maintaining the temperature to the therapeutic range may be used.
Alternatively, the flow rate of the irrigant may be controlled by starting the irrigant at the therapeutic temperature range at a low flow rate to acclimate the tissue to the heat, then optionally increasing the irrigant flow rate after the patient becomes acclimated to the temperature. This method of control has the advantage of not requiring the irrigant temperature to change which requires a significant amount of energy to heat the irrigant quickly.
It may be desirable to provide the therapeutic effect only on the bleeding nasal passageway rather than both the bleeding and contralateral passageway. Therefore, a device capable of motivating therapeutic irrigant into the bleeding nasal passageway then stopping the flow to allow the irrigant before allowing the irrigant to reverse direction and exit the nare of the bleeding passageway.
In certain situations, it may be desirable to lavage the bleeding nasal passageway by inserting a catheter into the bleeding nasal passageway wherein the catheter is configured to seal the choana such that irrigant flows into the bleeding nasal passageway and exits the nare. The device provides irrigant first at a comfortable temperature and pressure, the device then raises the temperature of the irrigant to the therapeutic temperature, pressure, and volume adequate to provide the therapeutic effect.
One method for reducing the likelihood of water aspiration into the lungs is to configure the device such that the patient holds the head tilted forward to ensure the irrigant flows into the first nare and nasal passageway, around the choana, through the contralateral nasal passageway, and out the contralateral nare and away from the patient.
A device designed to treat epistaxis or upper gastrointestinal bleeding is desirable because patients with either condition typically present to an urgent care center or emergency, department for treatment. There are two types of upper gastrointestinal bleeding, variceal and non-variceal. Variceal bleeding tends to be more diffuse with bleeding from multiple sites in the stomach and is difficult to treat with endoscopic techniques. Non-variceal bleeding is arterial bleeding that tends to be profuse and bleeding from a single site. It is typically treated endoscopically with a variety of technologies. Upper gastrointestinal bleeding is challenging to treat because the blood enters the stomach and disguises the location of bleeding. Therefore, a technology to stop bleeding, and clear blood from the stomach is needed to improve identification of the bleeding site for non-variceal bleeding. Furthermore, a technology to stop variceal bleeding is needed because few therapies are available to treat this condition.
An irrigant therapy heating and pump device includes a reservoir to hold a source of irrigant such as water or saline solution, a pump motor connected to a circulating impeller and/or a pumping impeller, a irrigant heating and temperature control system, irrigant passageways, a power switch, and a valve. A therapy switch controls a valve assembly which when the valve assembly is open, enables a flow of irrigant through the irrigant passageway from the reservoir to exit the nozzle. Therapy interface devices described infra are connected to the nozzle and deliver the therapeutic irrigant to the site where therapy is desired. It is understood that the irrigant may involve other irrigant irrigants beside water and saline solution.
Another embodiment includes the features described herein with the addition of an effluent receptacle, and a means to provide suction of effluent from the therapy site into the effluent receptacle.
The irrigant therapy heating and pump devices described herein may optionally include a means for filtration or sterilization of the irrigant irrigant.
In one embodiment, a device is provided for treating a bleeding nasal passageway. The device includes the irrigant therapy heating and pump device described herein and a section of tubing connected to the nozzle on the proximal extremity of the tubing and a nasal interface connected to the distal extremity of the tubing. The nasal interface engages an epistaxis patient's flare to deliver therapeutic irrigant to one nasal passageway and out of the contralateral nasal passageway. In the embodiment without the effluent receptacle, the irrigant flows out of the contralateral flare and into a basin or sink. In the embodiment with the effluent receptacle, a second nasal interface is provided wherein the second nasal interface engages the contralateral nare and the therapeutic irrigant is recovered and flows into the effluent receptacle.
Another embodiment utilizing the same components listed herein is configured to motivate the temperature-controlled irrigant into one nasal passageway then abruptly stopping the flow of the irrigant prior to it reaching the choana, then allowing the irrigant to reverse its direction and flow out of the same nare that it entered. This embodiment may include a valve mechanism to allow the effluent to flow into an effluent receptacle rather than flowing retrograde into the irrigant receptacle. This embodiment exposes only one nasal passageway to the therapeutic irrigant. This embodiment has the advantage of exposing only one nasal passageway to the therapeutic irrigant thereby not unnecessarily causing the therapeutic effects in the second nasal passageway.
The present invention solves the problem of epistaxis patients aspirating irrigant by using an apparatus that causes the irrigant to flow around the septum and out of the contralateral nasal passageway without the use of a balloon to block the choana. This is accomplished with an apparatus that induces the patient to flex the head forward during use to cause the outflow of therapeutic irrigant directly into a basin. By positioning the head forward and by controlling the irrigant flow rate within the prescribed therapeutic range, the irrigant flows into the first nasal passageway, around the posterior margin of the septum, into and through the contralateral nasal passageway before exiting the contralateral nare thereby eliminating the risk of aspirating therapeutic irrigant. When the irrigant flow rate is too high, there is a risk of irrigant at least partially flowing into one or both of the Eustachian tubes which may cause patient discomfort. Additionally, when the irrigant flow rate is too high, there is a risk of irrigant at least partially flowing posteriorly through the choana where it may be aspirated by the patient.
Another embodiment of this invention involves an apparatus with two irrigant reservoirs such that irrigant flows in a closed circuit between the two reservoirs. The first reservoir contains irrigant that is pumped within a prescribed flow rate range into the first nasal passageway, past the posterior margin of the septum, then into the contralateral nasal passageway before it flows out the contralateral nare, through tubing and into a second reservoir. The second reservoir is fluidly connected to the first reservoir such that as the irrigant flows out of the first reservoir, air from the second reservoir flows into the first reservoir thereby lowering the pressure in the second reservoir and inducing the irrigant to flow into the second reservoir rather than flowing posterior to the choana where it has an increased likelihood of being aspirated.
Another embodiment is an apparatus described herein that has two heat settings, the first heat setting heats the irrigant to a temperature lower than the therapeutic temperature range of 46 degrees Celsius to 52 degrees Celsius. The second heat setting heats the irrigant to within the therapeutic range of 46 degrees Celsius to 52 degrees Celsius. The first heat setting may be used to condition an epistaxis patient to the sensation of heated water flowing through the nasal passageways prior to increasing the temperature to within the therapeutic range. The temperature change may be done automatically by the apparatus or the patient may manually change a switch position. The lower irrigant temperature setting may also be used to heat the irrigant to a comfortable temperature when using the apparatus to rinse the nasal passageways when epistaxis is not present.
Another embodiment is an apparatus described herein that has two flow rate settings, the first flow rate setting pumps the irrigant at a low flow rate in the range of 2 cc/sec to 6 cc/sec then after a preset time or volume of irrigant flows to the therapy site, a second, higher flow rate commences to hasten the therapeutic effect. The lower flow rate setting may be used to condition an epistaxis patient to the sensation of heated water flowing, through the nasal passageways prior to increasing the flow rate of the irrigant to a more effective therapeutic range. The flow rate change may be done automatically by the apparatus or the patient may manually change a switch position. The lower flow rate setting may also be used to provide a more tolerable therapy for patients who are unable to comply with the higher flow rate therapy or when using the apparatus to rinse the nasal passageways when epistaxis is not present.
One embodiment is a reservoir containing irrigant that is positioned inside a heating medium such as water or a heater to heat the irrigant to the therapeutic temperature. When the irrigant temperature is within the therapeutic range, the reservoir is removed from the heating medium and the irrigant is motivated to flow into the nasal passageways by pouring, pumping, or squeezing the reservoir.
Any method of motivating irrigant flow into or through the nasal passageway may be used in addition to a pump such as the force of gravity or an air pressure differential between the reservoir and effluent. Furthermore, the pump may be powered in any manner such as using electrical power from batteries or from an alternating current source or via a manual pump.
A method of treating epistaxis wherein irrigant heated to the range of 46 degrees Celsius to 52 degrees Celsius is motivated to flow through one nare and its nasal passageway around the nasal septum, through the contralateral nasal passageway and exiting the contralateral nare with a sufficient volume of water to cause hemostasis.
A method of treating epistaxis wherein irrigant heated to the range of 46 degrees Celsius to 52 degrees Celsius is motivated to flow through one nare and its nasal passageway around the nasal septum, through the contralateral nasal passageway and exiting the contralateral nare with a sufficient volume of water to cause hemostasis such that the rate of water flow is controlled to control the amount of heat delivered to the tissue thereby providing a tolerable treatment. This control may be either automatically controlled or patient controlled. If patient controlled, the patient will be able to provide the therapy within the temperature range but may slow the flow of irrigant to provide a more tolerable therapy.
A method for treating bleeding in a nasal cavity is provided including sealing the nares of a user to a device including an associated irrigant passageway in communication with a irrigant reservoir and a irrigant effluent receptacle. The irrigant passageway, reservoir, temperature controller, and irrigant heating element are integrally assembled in the device. The irrigant may be heated and controlled solely in the irrigant passageway or in the irrigant reservoir or it may be heated and controlled in both locations or it may be heated in the reservoir and controlled in the irrigant passageway. The temperature of the irrigant is controlled to be maintained within the therapeutic range of 46 degrees Celsius to 52 degrees Celsius when it flows from the device and into the patient's nare. The irrigant is motivated to flow through the bleeding nasal passageway either by flowing directly through the nare of the bleeding passageway or by entering through the contralateral nare, through the contralateral nasal passageway, around the posterior margin of the nasal septum, and into the bleeding nasal passageway before flowing out of the nare.
Another method of treating bleeding in a nasal cavity is provided including sealing the nare of a bleeding nasal passageway to a device including an associated irrigant passageway in communication with a irrigant reservoir and a irrigant effluent receptacle. The irrigant passageway, reservoir, temperature controller, and irrigant heating element are integrally assembled in the device. The irrigant may be heated and controlled solely in the irrigant passageway or in the irrigant reservoir or it may be heated and controlled in both locations or it may be heated in the reservoir and controlled in the irrigant passageway. The temperature of the irrigant is controlled to be maintained within the therapeutic range of 46 degrees Celsius to 52 degrees Celsius when it flows from the device and into the patient's nare in the bleeding passageway. The irrigant is motivated to flow into the bleeding nasal passageway, then stops flowing before it is motivated either by the force of gravity or suction to flow out of the same nare that it entered the nasal passageway.
Another method of treating bleeding in a nasal passageway is provided to improve patient comfort by enabling the patient to condition themselves to the therapeutic temperatures wherein irrigant at a temperature less than 46 degrees Celsius is motivated to flow into or through a bleeding nasal passageway then the temperature of the irrigant is increased and maintained in the range of 46 degrees Celsius to 52 degrees Celsius.
Patient comfort and hemostasis are achieved when the irrigant flow rate maintained between 2.5 cc/second and 10 cc/second when the irrigant is at 50 degrees Celsius. Temperatures between 48 degrees Celsius and 50 degrees Celsius are more tolerable and provide adequate therapeutic effect as compared to temperatures above 50 degrees Celsius. The ideal balance of patient comfort, volume of irrigant, and flow rate are temperatures between 48 degrees Celsius and 50 degrees Celsius, 1000 cc liquid, and 3 cc per second to 5 cc per second.
The heater 17 may include an electrically resistive heating wire such as nickel chromium wire to increase the temperature of the irrigant in the reservoir 2. These heater wires 18, 19 conduct the electricity from an electrical relay to the heater 17. The electronic controller 20 controls the various functions of the system such as irrigant temperature by adjusting the amount of electrical energy conducted to the heater 17 based on: (i) the temperature information provided by the temperature sensor 15; (ii) the irrigant flow rate exiting the irrigant nozzle 6 by adjusting the speed of the motor 22 based on the information provided by an irrigant flow rate sensor 24; (iii) preventing the irrigant valve 29 from opening until the irrigant is within the therapeutic temperature range, and (iv) providing information for the LCD display 4.
The motor 22 simultaneously spins both the recirculating impeller 12 and the main impeller 23 to motivate irrigant to flow out of the recirculating impeller nozzle 13 and the irrigant nozzle 6. The irrigant flow rate sensor 24 provides irrigant flow rate information to the controller 20 to enable adjustments to speed of the motor 22, which in turn adjusts the irrigant flow rate. A main impeller shaft 25 connects the motor 22 to the main impeller 23. A main impeller inlet tube 26 fluidly connects the reservoir 2 to the main impeller 23. An LED on the outside of the unit illuminates the indicator RED when the unit is on but the irrigant temperature is not in the therapeutic range and the indicator GREEN when the unit is on and the irrigant temperature is in the therapeutic range. A start button on the outside of the unit is actuated by the user to commence the therapy by opening the irrigant valve 29 to enable the flow of irrigant to the main impeller 23, where the irrigant is then motivated to flow out of the nozzle 6 and to the site of therapy.
In another embodiment, a device is provided for treating bleeding in the stomach. The device is the irrigant therapy heating and pump device with the effluent receptacle described herein and includes at least one conduit configured to communicate with the stomach. The conduit may be used for the therapeutic irrigant to flow into the stomach. Additionally, the same conduit may be used for the contents of the stomach and the therapeutic irrigant to flow from the stomach and into the effluent receptacle. If a single conduit is used for flow in both directions, a valve is necessary to direct the irrigant from the stomach and into the effluent container and from the reservoir into the stomach. It is understood that the irrigant may include substances to stop bleeding.
Any method of motivating irrigant flow to lavage the stomach may be used in addition to a pump such as the force of gravity or an air pressure differential between the reservoir and effluent container. Additionally, a pump to motivate irrigant into the stomach may be used in concert with a source of vacuum to draw irrigant and irrigant out of the stomach. Furthermore, the pump and vacuum source may be powered in any manner such as using electrical power from batteries or from an alternating current source or via a manual pump.
Another embodiment is similar to that described herein but does not collect the effluent and instead allows it to flow into a separate container, basin, or drain.
A method of treating upper gastrointestinal bleeding is provided wherein a conduit (such as a nasogastric tube) with at least one lumen is positioned to fluidly communicate with a patient's stomach wherein the stomach is lavaged with an irrigant in the temperature range of 46 degrees Celsius to 52 degrees Celsius. A single lumen conduit may be used to both lavage the stomach with irrigant, then let the irrigant reside in the stomach for a period of time before evacuating at least a portion of the irrigant through the single lumen conduit. Alternatively, a dual lumen conduit may be used where one lumen is used for flow into the stomach and the second lumen is used for flow out of the stomach to circulate irrigant through the stomach and control the volume of irrigant in the stomach.
Referring still to
In certain embodiments, the irrigant is motivated to travel from the irrigant source 50 to the heating apparatus 300 via a gravity feed, a pressure differential, a mechanical pumping system, or other similar methods.
The embodiments of the systems depicted in
Referring still to
The treatment catheters depicted in the
In the heating element 350, a liner 560 at least partially surrounds the fluid passageway 358, and isolates the fluid passageway from the electrodes 355a, 355b so that the fluid passing through the fluid passageway 358 is not brought into contact with the electrodes. In some embodiments, the liner 560 functions as a dielectric barrier and may be formed from an insulating material, such as but not limited to a plastic material such as polyimide. In various embodiments, the liner 560 may be part of the heating element body, and may be configured as a disposable sterile insert, that is inserted within and extends through the fluid passageway 358 to provide a sterile environment for the fluid to flow through while flowing through fluid passageway. In some embodiments, the liner 560 is part of the sterile environment used in contact with and to provide a conduit for the flow of fluid through the fluid passageway 358, and is removable and disposable after use in a fluid warming procedure utilizing heating element 350. A heating element body may be configured to hold the electrodes 355a, 355b in a position spaced apart from one another and proximate to the fluid passageway 358, such as by being held by a first side plate 352a, and a second side plate 352b. Electrode 355a and/or electrode 355h may be partially or wholly embedded within a body in some embodiments in order to maintain the proper positioning of the electrodes relative to each other and to the liner 560 and the fluid passageway 358.
As further described below, the heating element 350 may be configured to provide and control electrical energy that is output from the electrical power source 351 and provided to the electrodes 355a, 355b, in order to provide a controlled heating of the fluid flowing through the fluid passageway 358, such as a fluid intended for introduction into a patient, while the fluid flows through or is present within the fluid passageway. The heating element 350 may be further configured to warm the flow of fluid through the fluid passageway 358 while maintaining a sterile environment with respect to any of the passageways and fluid conduits that conic into direct contact with the fluid being heated subsequent to the introduction to the patient.
In some embodiments, heat energy is transferred to the irrigant via conduction, convection, microwave energy, or other equivalent forms of heating a liquid. In some embodiments, the preferred method of heating the irrigant is via non-contact radio-frequency heating.
Embodiments of the non-contact radio-frequency heating may be performed using frequencies in a range of 10 kHz to 30 MHz, or as high as 100 MHz, or as high as 300 GHz, which may allow a volume of liquid to be heated faster with a lower surface area to volume ratio as the energy is transferred into the liquid more uniformly. The energy may also be transferred into the liquid through a non-conductive surface to eliminate the risk of forming steam and/or bubbles due to “hot spots” generally accompanied with rapid heating using conductive methods. The end result is similar to microwave heating of a liquid except higher electrical to thermal efficiencies can be realized. Using a resonant inverter at megahertz frequencies also may provide very fast response time and fine control over the heating system. Strategies for passive/natural power factor correction may be incorporated that limit or eliminate the need for an active power factor correction stage common in more conventional switching regulators. In various embodiments, the control circuitry of the control unit may provide output signals to control a device, such as fluid pump, wherein the flow rate of the liquid is adjusted so as to maintain the monitored temperature at, or within a band around, a constant value.
In various embodiments, the passageway for the flow of fluid to be heated includes a flexible passageway. In various embodiments, the fluid to be heated is an ionic liquid. In various embodiments, the fluid to be heated is saline, and is physiological saline. In various embodiments, wherein the temperature of the fluid being heated is to be maintained within a temperature range of between 49° C. and 51° C., inclusive. In various embodiments, the fluid exiting the conduit conveying the heated fluid from the non-contact radio-frequency heating element is configured for conveying heat to a liquid and delivering said liquid at a temperature elevated above that of the human body into an external body orifice, such as but not limited to a urinary meatus of a patient. Various embodiments further include a catheter extending through the urethra of a patient for receipt within the bladder and configured to convey a fluid heated by a non-contact radio-frequency heating unit to the bladder of a patient.
In various embodiments, the control unit includes a resonant inverter, such as but not limited to a Class E resonant inverter. In various embodiments, the Class E resonant inverter further comprises a wide-bandgap transistor, and/or wherein the signal driving the gate of the transistor comprising the Class E resonant inverter is supplied by the microcontroller. In various embodiments, the supply to the Class E resonant inverter is the unfiltered rectified line voltage. In various embodiments, the input voltage of the resonant electrical waveform generator is configured to vary in time at the fundamental of the line frequency (50 Hz or 60 Hz), and as a result the current drawn by the electrical waveform generator scales with voltage. If the voltage at the input of the electrical waveform generator is allowed to drop nearly to zero in sync with the rectified line, the electrical waveform generator itself may present approximately a resistive load to the line, and therefore nearly unity power factor can be achieved without any active or passive filtering elements.
In various embodiments, one or more of the temperature sensors configured to provide an output signal to the control unit may be read by the control circuitry during an OFF cycle of the modulation of the electrical output waveform(s) being provided to the electrode output terminal of the control unit. Temperature (and other) measurements may be susceptible to noise from switching power converters. Incorporation of temperature sensor(s) that can be read during the off-cycle modulation such that no switching noise is present, greatly improving the accuracy of the temperature reading. In various embodiments, one or more of the temperature sensors configured to provide an output signal to the control unit may be read during a minimum voltage level of the rectified line voltage. The gating of the resonant electrical waveform generator is disabled at the minimum rectified line voltage at the point of approximately zero power such that the temperature reading and off period due not adversely affect the power factor characteristics of the system.
In various embodiments, the ON and OFF switching cycles and the modulation periods may be synchronized with the line voltage or other electrical power input provided to the control unit. In various embodiments, the principal AC frequency; or the duty cycle of the transistor gate drive signal; are adjusted so as to optimize the heating efficiency; delivered power; or the power factor of the apparatus. As input voltage to the resonant electrical waveform generator varies with the rectified line voltage or otherwise, the optimal switching frequency and/or duty cycle may be affected, leading to reduced efficiency, and/or power factor. Varying frequency and/or duty cycle can lead to optimal efficiency and power factor for a given instantaneous input voltage or load impedance. Frequency and/or duty cycle may also be used to control power delivered to the load by deliberately tuning/detuning the impedance seen by the electrical waveform generator.
In various embodiments the control unit in conjunction with a non-contact radio-frequency heating element may utilize high voltage DC pulses to transfer electrical energy into a liquid. The process of pulse electric field sterilization (PEF) is a method of applying high voltage DC pulses (could be bipolar DC voltages) to a liquid in order to destroy the cell walls of any bacteria that may be present within the liquid. In addition to sterilizing the liquid, the temperature of the liquid also increases moderately. PEF can be used to both sterilize and heat the liquid in real-time. The DC pulses can be on the order of 1 microsecond or greater in length. Generally, electric field strengths of 800 V/mm or higher are desired to achieve significant bacteria reduction in a liquid. The electrode strategy is similar to the AC method but in various embodiments may have exposed electrodes in contact with the liquid, such as metal electrodes.
In some embodiments, the liner 560 can be replaced each time an irrigant source is connected to the heating apparatus. For example, in an embodiment in which the irrigant source is a saline bag, multiple saline bags may be required for the bleeding treatment. If so, each time the saline bag is disconnected from the heating apparatus (and/or the pump), a new liner 560 can be inserted into the heating element. In another example, an additional therapeutic agent may be added to a first irrigant source and that agent may not be desired to be added to the second irrigant source. In this example, placing a new liner into the heating element prevents residue of the therapeutic agent from being present in the irrigant supplied by the second irrigant source.
There are several advantages to the in-line heating apparatus disclosed herein. The heating apparatus is able to provide quick heating of a volume of irrigant as that irrigant flows through the heating element. Using feedback from sensors, the controller unit precisely controls the temperature and the flow rate of the irrigant through the heating element and into the treatment catheter. The replaceable liner allows for the use of readily available irrigant sources, such as saline bags, and allows for rapid exchange of those irrigant sources during a single treatment session. The replaceable liner allows the heating apparatus to be used with multiple patients without requiring sterilization of the heating element in between patients.
An in-line heating apparatus as disclosed herein may also be used in embodiments in which the irrigant fluid is used to maintain a structure to therapeutic temperature at the treatment site. For example, the treatment catheter may include a structure that is configured to substantially conform to the tissue at the treatment site. Such a conforming structure can include, for example, a balloon, expandable arms, or combinations thereof.
The conforming structure can be filled with the irrigant fluid to bring the conforming structure to a therapeutic temperature, to maintain the conforming structure at a therapeutic temperature, or both. In some embodiments, the conforming structure could be brought to a temperature at or near the therapeutic temperature prior to the treatment catheter being inserted into the patient.
The conforming structure can also be filled, inflated, expanded, or otherwise made to conform to the body cavity using the irrigant fluid. In an embodiment in which the conforming structure include a balloon, the balloon is connected to a supply lumen to fill the balloon with heated irrigant fluid and a drainage lumen to drain the balloon of the irrigant fluid after the irrigant fluid has transferred heat to the body cavity via the balloon. The irrigant fluid may be circulated within the balloon to maintain the balloon within the therapeutic temperature range, such as in the range of 46 degrees Celsius to 52 degrees Celsius.
The balloon may have a soft pliable wall made from a non-elastomeric polymeric material. The non-elastomeric balloon can be filled with fluid at a low pressure, thereby conforming to the anatomy and applying the warmth from the balloon evenly to the target tissue.
As disclosed herein, 48-52 degrees Celsius is a preferred temperature range for the treatment of bleeding with a heated irrigant. The results of
Element 250 includes a heating element body 251 (hereinafter “body 251”) having a first end coupled to a fluid input conduit 253 and a second end that is opposite the first end, the second end coupled to a fluid output conduit 254. A hollow passageway 252 extends from the first end to the second end of the body 251, forming a fluid passageway to transport a flow of fluid entering the first end of body 251 as provided by the fluid input conduit 253 to the second end of the body and to the outlet provided by fluid output conduit 254. Element 250 further includes one or more sets of electrodes positioned within body 251, the electrodes positioned proximate to passageway 252, and sealed from passageway 252, for example by a portion of the body 251, so that the electrodes will not come into contact with the fluid flowing through the passageway. Embodiments of passageway 252 are not limited to being formed as a single straight passageway, and in various embodiments may include a set of parallel passageways, or a single passageway that winds along, for example in a serpentine path or other non-linear path, through the body 251 of element 250.
As illustrated in
Electrical energy provided by control unit 201 to electrode 255 and return electrode 256 may establish an electromagnetic field in an area between the electrodes, and thus be imposed onto a fluid included within passageway 252. The field established between the electrodes may then induce non-contact RF heating of the fluid included in the passageway. By controlling the amount and format to the electrical energy provided to electrode 255 and return electrode 256, control unit 201 may be configured to controllably heat a flow of fluid passing through passageway 252 of element 250. In various embodiments, the fluid to be heated is saline, or a saline solution, which is being provided as a non-limiting example of a fluid that may be introduced into a patient after passing through element 250 and being heated to a desired temperature before being introduced into the patient. In addition, because the saline solution is being provided to the patient and in a medical setting, it is important that the heating of the saline be accomplished without contamination of the saline as part of the heating process. As shown in
In various embodiments, element 250 of system 200 is configured to couple to a fluid source 260, wherein fluid source 260 may include a pump or other mechanism to produce a flow of fluid, such as a flow of saline, to fluid input conduit 253. Fluid input conduit 253 is coupled to the first end of body 251, and is in fluid communication with passageway 252. A flow of fluid, such as saline provided by fluid source 260, may flow through passageway 252 and between electrode 255 and return electrode 256, and exit body 251 through fluid output conduit 254. As the fluid flows through passageway 252, electrical energy under the control of control unit 201 may be provided to electrode 255 and return electrode 256 and produce non-contact RF heating of the fluid within passageway 252. One or more sensors, such as temperature sensor 257, may be positioned proximate to passageway 252, and may be configured to sense the temperature of the flow of fluid as the fluid passes through and exits passageway 252. The sensor(s) generate one or more sensor output signals that are indicative of the sensed temperature of the fluid passing through and/or exiting passageway 252, and provide the output simians) to a sensor input 218 of control unit 201, for example though sensor input lines 258. In some embodiments, sensor input 218 may include or be coupled to a multiplexer 219 configured to multiplex a plurality of input signals from multiple sensors into control circuitry 210, for example using some predefined sampling rate. Control unit 201 may be configured to receive and process the sensor input signal(s)) related to temperature of the fluid, and to further control the output of electrical energy being provided to electrode 255 and return electrode 256 by controlling the electrical output being provided to electrode output terminal 206 and electrode return terminal 207 of the control unit.
In addition to temperature sensing, one or more other types of sensors, such as one or more flow sensors illustratively represented by sensor 259, and one or more ambient temperature sensors illustratively represented by sensor 264, may be included in system 200 to provide additional feedback to control unit 201. In various embodiments, flow sensor 259 is configured to determine a flow rate or a flow volume passing by the sensor, and provide an output signal to control unit 201 indicative of the flow rate or the volume of flow passing by the sensor. This flow rate/flow volume information may be received by control unit 201, and further incorporated into the control of the electrical energy being provide by the control unit to element 250 in order to maintain the temperature control of the flow of fluid passing through element 250 in a desired manner.
In various embodiments, ambient temperature sensor 264 is configured to determine an ambient temperature in one or more areas outside element 250, such as an ambient temperature of the area where the fluid source 260 is located, and/or an ambient temperature in the area where the fluid output conduit 254 passes between the element 250 and the point where the fluid is introduced into a patient. Ambient temperature sensor 264 may be configured to generate and to provide an output signal to control unit 201 indicative of the ambient temperature in one or more areas located outside of element 250. This ambient temperature information may be received by control unit 201, and further incorporated into the control of the electrical energy being provide by the control unit to element 250 to maintain the temperature control of the flow fluid passing through element 250 in a desired manner.
As shown in
As illustrated for system 200, input power processing circuitry 203 is coupled to at least one electrical power input source (not specifically shown in
Regardless of the power input configuration, input power processing circuitry 203 may be configured to perform conditioning of the incoming electrical power to provide electrical power that is coupled to the electrical components and devices included in control unit 201, including the electrical waveform generator 204, control circuitry 210, and power-delivery circuitry 205. For the sake of clarity and simplicity, actual lines showing the specific power connections between the electrical components and devices of control unit 201 and the input power processing circuitry 203 may not be illustrated in
In various embodiments, all or various combinations of these power conditioning processes may be performed by input power processing circuitry 203 on the power being provided by the input power processing circuitry to the electrical components and devices included in control unit 201. In one embodiment, the electrical power input provided to input power processing circuitry includes 120 VAC 60 Hz electrical power, and the output power provided by the input power processing circuitry 203 to the power-delivery circuitry 205 includes a rectified waveform. As further described below, an intermediate electrical waveform generated by the electrical waveform generator 204 and provided to the power-delivery circuitry 205 is used to switch ON and OFF, and otherwise control the coupling of the electrical power provided by the input power processing circuitry 203 to the electrodes of the element 250 through the electrical devices, such as switching devices, included in the power-delivery circuitry.
As shown in
The type of circuitry utilized by RF source 204A to generate the electrical waveform is not limited to any particular type of circuitry or to any particular technique for generating an electrical waveform. In some embodiments, RF source 204A includes one or more high speed timers configured to generate a varying voltage output signal. In various embodiments, RF source 204A includes a voltage-controlled oscillator, or some other type of oscillator, configured to generate a varying voltage output signal. Other types of circuitry and techniques may be utilized as part of RF source 204A to generate the electrical waveform having a varying voltage output and are contemplated for use as embodiment(s) of the RF source included in control unit 201.
As shown in
In addition to or instead of controlling the frequency of the electrical waveform provided by RF source 204A, modulator 204B may be configured to variably control a maximum voltage level or a voltage range, such as peak-to-peak voltage, of the electrical waveform received from the RF source. For example, modulator 204B may variably increase or decrease the amount of voltage variation, including varying a maximum voltage level or varying a voltage range (peak-to-peak voltage) of the electrical waveform received by the modulator from RF source 204A. The variations in the voltage level(s) generated by modulator 2049 may then be provided as the intermediate electrical waveform that is output from the modulator. Controlling variations in the voltage levels of the intermediate electrical waveform output by modulator may be used to control the overall amount of electrical energy that is to be delivered to the electrodes of a non-contact RF heating element, such as element 250, that is being regulated by the intermediate electrical waveform as further described below.
In some embodiments, modulator 2049 may be configured to modulate the electrical waveform received from the RF source 204A by varying the frequency of the electrical waveform to generate the intermediate electrical waveform that is then provided as an output from the modulator. Controlling variations in the frequency of the intermediate electrical waveform that is being output by modulator may be used to control the overall amount of electrical energy that is delivered to the electrodes of an non-contact RF heating element, such as element 250, that is being regulated by the intermediate electrical waveform as further described below.
As shown in
The switching devices included in the power-delivery circuitry 205 are also configured to be controllably switched OFF, and thus to disconnect the electrical power being provided by power lines 220 to the power-delivery circuitry from the outputs of the power-delivery circuitry coupled to electrode output terminal 206 (OUT 1) and the electrode return terminal 207. In various embodiments, during the periods of time when the switching devices are switched ON, the switching devices included in the power-delivery circuitry 205 may be further controlled by the intermediate electrical waveform received from the electrical waveform generator 204 to vary for example the voltage level being provided at the electrode output terminal coupled to the switching device(s) in order to provide a varying voltage output waveform having variations corresponding to the variations of the intermediate electrical waveform to the electrodes of element 250. As further described below, the various parameters of the intermediate electrical waveform generated by the electrical waveform generator 204 may be controlled by input signals provided to the electrical waveform generator by control circuitry 210. In various embodiments, electrical waveform outputs provided to the electrodes of element 250 as an output from the power-delivery circuitry 205 and as controlled by the intermediate electrical waveform generated by electrical waveform generator 204 may be configured to produce non-contact radio-frequency heating of a fluid flowing through passageway 252 of the element.
As shown in
Control circuitry 210 may utilize one or more techniques to control the overall level of electrical energy provided to the electrodes of a non-contact radio-frequency heating element, such as element 250, and thus control the heating of a fluid flowing through the heating element. In various embodiments, control circuitry 210 may provide one or more control signals to input power processing circuitry 203. These control signals may allow the control circuitry to modify one or more parameters of the power that is to be or is being provided by the input power processing circuitry to the power-delivery circuitry 205. In various embodiments, control circuitry 210 may provide one or more control signals to electrical waveform generator 204 configured to control and/or vary the frequency of the intermediate electrical waveform being provided as an output from the electrical waveform generator. Varying the frequency of the electrical waveform generator's intermediate electrical waveform may change the overall impedance of the circuit that includes a fluid flowing past and/or positioned between electrodes of a non-contact radio-frequency heating element, and thus control the overall heating of the fluid. In various embodiments, control circuitry 210 may provide one or more control signals to electrical waveform generator 204 that are configured to control and/or vary one or more of voltage levels, such as peak voltage and/or peak-to-peak voltage, of the electrical output waveform provided as an output from the power-delivery circuitry 205. Varying one or more voltage levels of the intermediate electrical waveform being provided as an output from the electrical waveform generator 204 may change the overall level of electrical power being delivered by the power-delivery circuitry 205 to the electrodes of a non-contact radio-frequency heating element, such as element 250, and thus control the overall heating of the fluid passing through the non-contact radio-frequency heating element.
In various embodiments, control circuitry 210 may provide one or more control signals to electrical waveform generator 204, for example to modulator 204B, that are configured to control and/or generate a pulsed output of the intermediate electrical waveform provided as an output from electrical waveform generator 204 to the power-delivery circuitry 205, and thus control a duty cycle for the application of electrical power to the electrodes of a non-contact radio-frequency heating element, such as element 250. Controlling a duty cycle of the electrical power being provided as an output from the power-delivery circuitry 205 may change the overall level of electrical power being delivered to the electrodes of a non-contact radio-frequency heating element, and thus control the overall heating of the fluid passing through the non-contact radio-frequency heating element.
Various embodiments of control unit 201 include a user interface 214 communicatively coupled to control circuitry 210. User interface 214 may be configured to allow electrical communications, for example but not limited to communication utilizing a RS-232 format, between control circuitry 210 and one or more other computer systems, such as computer system 265 as illustrated in
In various embodiments, control unit 201 may include a temperature output 216 that is electrically coupled to control circuitry 210. Temperature output 216 may provide an output signal, such as a voltage output, that is indicative of a current temperature value for a fluid that is being heated by or at least flowing through the non-contact radio-frequency heating element coupled to control unit 201. The temperature output signal may in some embodiments be provided to a display device configured to visually display a value corresponding to the temperature indicated by the signal provided at the temperature output 216.
Control unit 201 may provide various features and perform various functions related to safety and regulation of a non-contact radio-frequency heating system such as system 200. For example, various types of shielding may be provided to limit or eliminate electromagnetic radiation associated with the higher frequencies that may be generated by and transmitted through the system. In various embodiments, certain fault conditions may be monitored for, and when detected may result in a shutdown and/or a power down of one or more portions of the control unit. For example, an overvoltage and/or an over current condition occurring in the power input power processing circuitry, 203, electrical waveform generator 204, and/or power-delivery circuitry 205 may be monitored for, and if any voltage or current levels exceed acceptable levels, one or all of these portions of the control unit 201 may be powered down. In various embodiments, the temperature of one or more switching devices, such as MOSFETs, that may be included in power-delivery circuitry 205 may be monitored, and if these temperature(s) exceed acceptable limits, the power-delivery circuitry 205 may be powered down. In various embodiments, a parameter related to a maximum fluid temperature sensed by one or more temperature sensors sensing temperatures of the fluid at or passing through the non-contact radio-frequency heating element coupled to the control unit may be monitored, and if the fluid temperature(s) exceeds any threshold level(s) set for fluid temperature, the control unit may shut down the electrical waveform generator and/or power-delivery circuitry of the control unit so that the electrical output waveform is disconnected from the electrode output terminal(s) of the control unit and is no longer being applied to the electrodes of the non-contact radio-frequency heating element. In various embodiments, a flow level or volume of fluid flow passing through the non-contact radio-frequency heating element is monitored, and if no flow is detected, or for example a minimum level of fluid flow is not detected, the control unit may be configured to stop providing electrical energy to the electrodes of the non-contact radio-frequency heating element, and thus cease any further heating of the fluid until and/or unless a fluid flow is detected, or the minimum level of fluid flow is re-established through the non-contact radio-frequency heating element.
In various embodiments the control circuitry 210 performs the monitoring and alarm function, and controls output signals to the electrical waveform generator 204 and/or the power-delivery circuitry 205 to power down or shut down portions of the control unit when an unacceptable, fault, or alarm condition is detected. In various embodiments, other devices, such as fuses and/or circuit breaker, which may or may not be controlled by the control circuitry 210, may provide protection, such as protection against electrical overloads within the control unit 201 and/or associated with the electrical power being provided to the non-contact radio-frequency heating element by the control unit and/or to the control unit from any electrical power input sources coupled to lines 202.
The overall wattage level of electrical energy provided by control unit 201 to a RF heating element, such as element 250, is not limited to any particular wattage, and in various embodiments is configured and controlled based on the particular application, such as the type of fluid being processed, the amount of heating of the fluid that is required, and/or the configuration of the RF heating element itself. In various embodiments, a control unit, such as control unit 250, is configured to provide an overall wattage level in a range of 0 to 500 watts of electrical power in a controlled manner to a RF heating element. Embodiments may include higher wattage levels for example up to and including 2000 watts or more, again depending on the application. In various arrangements, the application of the electrical energy to the fluid as part of the RF heating process may generate bubbles, such as gas bubbles, in the fluid. In various embodiments, operations utilizing the RF heating element may include positioning the exit end of the element in a vertical or upward orientation to: 1) allow for all bubbles to exit the tubing, 2) for preventing any new bubbles from getting trapped, 3) and/or allow any generated gas to escape. In various embodiments, one or more bubble sensors may be incorporated into a RF heating system, such as system 200, to detect the presence of gas bubbles in the fluid being heated, and to provide an output signal to the control unit 201 indicative of the presence or absence of bubbles that may be detected in the fluid. An embodiment of a bubble sensor may comprise a light source, such as but not limited to a laser light source, and a photo detector, such as but not limited to a photodiode, configured to detect the light provided by the light source. The bubble detector may be configured to provide an output signal that is indicative of the presence or absence of bubbles in the fluid. In various embodiments, the bubble sensor may be built into the RF heating element, and/or may be incorporated into the fluid output conduit, such as fluid output conduit 254 as shown in
As shown in
Following time T3, a subsequent time period 310 may include waveform 301 switched to an ON state, extending to time T4 as represented by arrow 310, wherein at time T4 waveform 301 is switched back to the OFF state for a time period represented by arrow 311 extending from time T4 to time T5. The time periods 310 and 311 represent another and subsequent ON/OFF switching cycle of waveform 301 having a duty cycle and an overall period that may be adjusted to control the overall amount of electrical power provided during this subsequent cycling of waveform 301. Additional switching cycles, as represented by the partially illustrated time period of at arrow 312, may follow after time T5 and may include variable time periods and/or variable duty cycles as described above for the previous ON/OFF switching cycles of waveform 301.
The ON/OFF switching of waveform 301 may represent a switching of an electrical power output from an electrical waveform generator (e.g., electrical waveform generator 204,
As shown in
As further illustrated in
As shown in
In various embodiments, the time period during which waveform 361 is provided as having a first frequency illustrated by arrow 365 may be varied, as illustratively indicated by double arrows 366, and/or the time period during which waveform 361 is provided as having a second frequency different from the first frequency, as illustrated by arrow 367 may be varied, as illustratively indicated by double arrows 368. In addition to varying frequency of waveform 361 over different and subsequent time periods, waveform 361 may be switched ON and OFF in a manner similar to that described above for waveform 301 and graph 3A. In the alternative or in addition to switching the waveform 361 ON and OFF, the overall peak-to-peak volte of waveform 361 may be varied in a same or similar manner as described above with respect to graph 3B and waveform 331.
As shown in
In various embodiments, each of electrodes 411, 412, 413, and 414 is electrically isolated from one another, and positioned above and proximate to passageway 252 of non-contact radio-frequency heating element 250. A return electrode 420 is electrically isolated from each of the electrodes 411, 412, 413, and 414, and is positioned below passageway 252 on an opposite side of the passageway relative to electrodes 411, 412, 413, and 414. As shown in
In various embodiments, electrode conductor wiring 422 may include shielding coupled to return electrode 420, and to electrode return terminal 207 of control unit 201, wherein separate sets of wiring may be utilized to couple and/or shield each individual electrode 411, 412, 413, and 414 along with a respective return conductors for coupling the respective electrode and return electrode 420 to control unit 201. In various embodiments, instead of being formed as a single electrode, return electrode 420 may comprise individual electrodes (not specifically shown in
In various embodiments, electrodes 411, 412, 413, and 414, along with return electrode 420, are generally formed having a planar flat shape. However, embodiments of the electrodes and the return electrode or return electrodes are not limited to having a planar flat shape, and may for example have a curved arch-shape the extends at least partially around the longitudinal axis 262 at some radial distance from the longitudinal axis while remaining electrically isolated from direct contact with all other electrodes included in the element 250.
In various embodiments, control unit 201 may be configured to individually control an electrical output waveform provided to each of the electrode output terminals, 401, 402, 403, and 404, thus providing individually controlled outputs to each of the electrodes 411, 412, 413, and 414, respectively. In various embodiments, control unit 201 may operate all of the electrode output terminals 401 at the same time with respect to a switched ON and OFF state for application of an electrical output waveforms to the electrodes. In various embodiments, control unit 201 or may operate these ON and OFF states to individually control the output of an electrical output waveform to the respective electrode output terminals, and thus to the electrodes of the element 250 on an individual basis, wherein one or more of the electrode output terminals may be switched to an OFF state while other ones of the electrode output terminals are switched to an ON state. In various embodiments, an added number of temperature sensors, for example five temperature sensors as illustrated in
In various embodiments, different electrical output waveforms, such as but not limited to the electrical output waveforms described above with respect to
The windings forming inductive coils 281, 282, 283, and 284 are not limited to any particular type of winding, or to any particular number of turns per used to form each coil, or to any particular type of material used to form the inductive coils. In some embodiments, each of inductive coils 281, 282, 283, and 284 comprises a same type of electrical conductor, such as a conductive metal such as copper, aluminum, silver, or gold, which may be used to form each winding, and a same number of turns of the electrical conductor. However, embodiments of the element 270 are not limited to having four coils in number, and may have more or less than four coils, including having just a single (one) coil. Further, embodiments of element 270 are not limited to having each of a plurality of coils included in the element comprising a same type of coil winding. For example, one or more of a plurality of coils included in element 270 may include more or less turns of winding of the electrical conductor used to form the inductive coil, and/or may be formed from a different electrical conductor, for example a different gauge of wire or other conductive element used to form the inductive coil(s).
In operation, control unit 201 may be configured to provide one or more electrical output waveform(s) to inductive coils 281, 282, 283, and 284 in order to generate an electromagnetic field in the area surrounding each inductive coil, including within the area surrounding each inductive coil included within passageway 278 of inner tube 273. The electromagnetic field(s) generated by inductive coils 281, 282, 283, and 284 may be configured produce heating for fluid that is flowing through or contained within the passageway 278. In various embodiments, control unit 201 applied a same electrical output waveform to each of inductive coils 281, 282, 283, and 284 at or over a same time period, including applying a pulsed electrical output waveform to each of the inductive coils 281, 282, 283, and 284 at a same period and same phase relative to the pulses of the electrical output waveform. However, embodiments may include control unit 201 providing different electrical waveform(s) to one or more of the inductive coils 281, 282, 283, and 284 at a same or at different times, wherein various combinations of the inductive coils 281, 282, 283, and 284 may be energized and de-energized at different time relative to one another and energized using different electrical output waveforms at a same or different time relative to the electrical waveform(s) being applied to energize other ones of the inductive coil. By varying and controlling the electrical waveform(s) used to energize the inductive coils 281, 282, 283, and 284, and/or the timing of the energization of each of the inductive coils 281, 282, 283, and 284, either individually or together is some combination, the heating of the fluid that is flowing through or contained within passageway 278 may be controlled.
Embodiments utilizing element 270 may be configured and operated to provide any of the features and to perform any of the functions related to heating, sterilization, or other processing of fluid as described throughout this disclosure, and any equivalents thereof. For example, as shown in
Embodiments of method 700 may include processing incoming electrical power to produce processed electrical power, (block 702). Processing of electrical power may include rectification, filtering, and voltage, current, and/or phase regulation of incoming electrical power. In various embodiments, processor(s) of the control circuitry may provide control signals, for example to an input power processing circuitry, to modify or control one or more parameters, such as a voltage or a power level provided an output of the electrical power processed and provided as an output from the input power processing circuitry.
Embodiments of method 700 may include generating and modulating an RF waveform to produce an intermediate electrical waveform, (block 704). Generation of an RF waveform may be performed by an RF source, such as RF source 204A (
Embodiments of method 700 may include controlling a power-delivery circuitry using the intermediate electrical waveform to control coupling of the processed electrical power to one or more sets of electrodes of a RF heating element (block 706). In various embodiments, the control provided by power-delivery circuitry may include switching ON and switching OFF the electrical coupling between the processed electrical power being provided to the power-delivery circuitry and the one or more sets of electrodes in order to provide a modulated or a pulsed electrical output waveform to the one or more sets of electrode included in the RF heating element, and thereby control the heating of a fluid flowing through or contained within the heating element. Embodiments of method 700 may include coupling the electrical output waveform from the one or more electrode output terminals of a control unit to one or more sets of electrodes positioned in a non-contact radio-frequency heating element through one or more electrical conductors, such as but not limited to one or more shielded co-axial cables. Providing the electrical output waveform from the one or more electrode output terminals to one or more sets of electrodes positioned in a non-contact radio-frequency heating element may result in a heating of a fluid passing between or contained within an area between the one or more sets of electrodes.
Embodiments of method 700 may include sensing parameters associated with a fluid flowing through and/or contained within the RF heating element (block 708). Sensed parameters may include but are not limited to sensing a temperature of the fluid, sensing a flow rate, or sensing a flow volume associated with the fluid.
Embodiments of method 700 may include determining, for example using control circuitry, adjustments to the electrical power that is/are being applied to the one or more sets of electrodes of the non-contact radio-frequency heating element based at least in part on the sensed parameters (block 710). In various embodiments, a determination of any adjustments to the electrical output waveform(s) is based on one or more sensed temperatures associated with the fluid being heated by the non-contact radio-frequency heating element. In various embodiments, a determination of any adjustments to the electrical output waveform(s) is based on one or more sensed flow rates or a sensed flow volume associated with the fluid being heated by the non-contact radio-frequency heating element.
Based on a determination of any adjustment that may need to be made to the electrical output waveform(s), method 700 returns to block 704, as indicated by return line 714, where further control of the electrical waveform generator and/or the power-delivery circuitry is performed based on any of the adjustments determined to be made at block 710. Heating of the fluid may continue in a loop including blocks 702 through 710 until an operator shuts the control unit that is performing method 700 off, or an alarm condition is detected (block 720).
When an alarm condition is detected, embodiments of method 700 may include shutting down the electrical waveform generator and/or the power-delivery circuitry of the control unit. Alarm conditions can include but are not limited to an over temperature detected for the fluid being heated by the non-contact radio-frequency heating element, an unacceptable condition related to the flow rate or flow volume associated with the fluid being heated by the non-contact radio-frequency heating unit, and/or an electrical or temperature condition associated with the control unit and/or the non-contact radio-frequency heating unit, such as a short circuit, loss of input electrical power to the control unit, and any unacceptable and detected over temperature, overcurrent, or overvoltage condition that might exist within the control unit. In various embodiments, the control unit is configured to output a warning signal, for example through a user interface, to one or more devices located external to the control unit, the warning signal(s) including information related to the detection of an alarm condition, and/or information related to the nature and the extent of the condition that generated the alarm condition.
As will be appreciated, aspects of the disclosure may be embodied as a system, method or program code/instructions stored in one or more machine-readable media. Accordingly, aspects may take the form of hardware, software (including firmware, resident software, micro-code, etc.), or a combination of software and hardware aspects that may all generally be referred to herein as a “circuit,” “circuitry,” “module,” or “system.” The functionality presented as individual modules/units in the example illustrations can be organized differently in accordance with any one of platform (operating system and/or hardware), application ecosystem, interfaces, programmer preferences, programming language, administrator preferences, etc.
Any combination of one or more machine readable medium(s) may be utilized. The machine-readable medium may be a machine-readable signal medium or a machine readable storage medium. A machine-readable storage medium may be, for example, but not limited to, a system, apparatus, or device, that employs any one of or combination of electronic, magnetic, optical, electromagnetic, infrared, or semiconductor technology to store program code. More specific examples (a non-exhaustive list) of the machine readable storage medium would include the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a machine-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable storage medium is not a machine-readable signal medium.
A first embodiment of the invention includes a method for treating a bleeding nasal passageway wherein an irrigant in the temperature range of 46 degrees Celsius to 52 degrees Celsius is motivated to flow into the first nasal passageway then past the posterior septal margin and through the contralateral nasal passageway and out the contralateral nare for a sufficient period of time and volume to cause hemostasis of the bleeding nasal passageway.
The first embodiment of the invention includes a method wherein the irrigant flow rate is between 2 cc/second and 12 cc/second.
The first embodiment of the invention includes a method wherein the irrigant flow rate is controlled by measuring the volumetric change of the irrigant in an irrigant reservoir.
The first embodiment of the invention includes a method wherein the irrigant flow rate is controlled by increasing or decreasing the rate of irrigant flow through a mechanism.
A second embodiment of the invention includes a device for treating a bleeding nasal passageway wherein the device incudes a reservoir capable of holding or receiving a irrigant, a heating system, temperature controller, irrigant pump, and nasal interface wherein the irrigant is heated by the irrigant heating system to a temperature in the range of 48 degrees Celsius to 52 degrees Celsius and the irrigant is motivated by the irrigant pump to flow into a first nasal passageway and past a bleeding site in the nasal passageway or a contralateral nasal passageway.
The second embodiment of the invention includes a device wherein the irrigant is at a temperature below 48 degrees Celsius and after the flow of irrigant commences, the irrigant heating system raises the temperature of the irrigant to within the range of 48 degrees Celsius to 52 degrees Celsius while it flows into the nasal passageway.
The second embodiment of the invention includes a device wherein the irrigant is motivated by the pump to flow at a rate between 2 cc per second and 12 cc per second.
The second embodiment of the invention includes an aspect wherein the device has two irrigant temperature settings, wherein the first irrigant temperature setting heats the irrigant to a temperature range between 35 degrees Celsius and 46 degrees Celsius and the second heat setting heats the irrigant to within the range of 46 degrees Celsius to 52 degrees Celsius wherein the device causes the irrigant to flow at a controlled rate and at a controlled temperature into first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway before exiting the contralateral nare.
The second embodiment of the invention includes an aspect wherein the device heats irrigant to within the temperature range of 35 degrees Celsius and 46 degrees Celsius and after reaching the temperature range, a preset volume of irrigant is induced to flow at a controlled flow rate into a first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway, and exits the contralateral nare; then the temperature of the irrigant is increased to within the range of 46 degrees Celsius to 52 degrees Celsius and irrigant at the temperature is induced to flow at a controlled flow rate into a first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway and exits the contralateral nare.
The second embodiment of the invention includes an aspect wherein the device heats irrigant to within the temperature range of 35 degrees Celsius and 46 degrees Celsius and after reaching the temperature range, irrigant is induced to flow at a controlled rate for a preset period of time into a first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway, and exits the contralateral nare; then the temperature of the irrigant is increased to within the range of 46 degrees Celsius to 52 degrees Celsius and irrigant at the temperature is induced to flow at a controlled rate into a first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway and exits the contralateral nare.
The second embodiment of the invention includes an aspect wherein the device has two irrigant flow rate settings, wherein the temperature of the irrigant is in the range between 42 degrees Celsius and 52 degrees Celsius and the first irrigant flow rate is in the range of 2 cc/min to 6 cc/min and the second irrigant flow rate is in the range of 5 cc/min to 12 cc/min wherein the device motivates the irrigant to flow at a controlled rate and at a controlled temperature into first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway before exiting the contralateral nare.
The second embodiment of the invention includes an aspect wherein the device motivates a preset volume of irrigant to flow at a first flow rate into a first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway, and exits the contralateral nare; then after the preset volume of irrigant has been motivated to flow out of irrigant reservoir, the flow rate of the irrigant is increased to flow at a second flow rate into a first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway and exits the contralateral nare.
A third embodiment of the invention includes a device configured to motivate the temperature-controlled irrigant into one nasal passageway then stops the flow of the irrigant prior to the irrigant reaching the posterior margin of the nasal septum, then the irrigant direction is reversed such that it flows out of the same nare that it entered the nasal passageway.
The third embodiment of the invention includes an aspect wherein the device incorporates a valve mechanism to divert the effluent away from the irrigant receptacle.
A fourth embodiment of the invention includes a device configured to treat either epistaxis or upper gastrointestinal bleeding using a irrigant to lavage the nasal passageway or the stomach wherein the irrigant temperature is in the range of 46 degrees Celsius to 52 degrees Celsius.
A fifth embodiment of the invention includes a device comprised of a reservoir for containing irrigant, a irrigant heating system, and a temperature control system wherein the reservoir contains irrigant that is heated in the range of 46 degrees Celsius to 52 degrees Celsius and the reservoir is configured with a spout to pour irrigant from the reservoir into the nasal passageway of the patient such that the irrigant flows past a bleeding site in the nasal passageway or a contralateral nasal passageway.
A sixth embodiment of the invention includes a device comprised of a reservoir for containing irrigant, a irrigant heating system, and a temperature control system wherein the reservoir contains irrigant that is heated in the range of 46 degrees Celsius to 52 degrees Celsius and the reservoir may be squeezed to motivate the irrigant into the nasal passageway of the patient such that the irrigant flows past a bleeding site in the nasal passageway or a contralateral nasal passageway.
A seventh embodiment of the invention includes a method for treating gastric bleeding wherein a irrigant in the temperature range of 46 degrees Celsius to 52 degrees Celsius is motivated to lavage a patient's stomach wherein the stomach has one or more bleeding sites and the irrigant flows out of the patient's stomach and flows into a collection receptacle.
An eighth embodiment of the invention includes a device for treating gastric bleeding wherein the device is comprised of a reservoir capable of holding or receiving a irrigant, a heating system, temperature controller, irrigant pump, and nasal interface wherein the irrigant is heated by the irrigant heating system to a temperature in the range of 46 degrees Celsius to 52 degrees Celsius and the irrigant is motivated by the irrigant pump to lavage a patient's bleeding stomach and the irrigant exits the bleeding patient's stomach and flows into a collection receptacle.
A ninth embodiment of the invention includes a method of treating epistaxis using an apparatus that induces the patient to position the head forward then inducing irrigant flow at a controlled temperature and at a controlled rate wherein the irrigant flows into the first nasal passageway, around the posterior margin of the septum, into the contralateral nasal passageway before exiting the contralateral nare.
The ninth embodiment of the invention includes a method wherein the irrigant flow rate is between 2 cc/second and 12 cc/second.
The ninth embodiment of the invention includes a method wherein the temperature of the irrigant is between 46 degrees Celsius and 52 degrees Celsius.
A tenth embodiment of the invention includes a device with two irrigant reservoirs such that irrigant flows in a closed circuit between the two reservoirs wherein the first reservoir contains irrigant that is pumped at a controlled flow rate and at a controlled temperature into the first nasal passageway, past the posterior margin of the septum, then into the contralateral nasal passageway before it flows out the contralateral nare, through tubing and into a second reservoir wherein the second reservoir is fluidly connected to the first reservoir such that as the irrigant flows out of the first reservoir, air from the second reservoir flows into the first reservoir thereby lowering the pressure in the second reservoir thereby inducing the irrigant to flow into the second reservoir after passing through the nasal passageways.
The tenth embodiment of the invention includes an aspect wherein the irrigant flow rate is between 2 cc/second and 12 cc/second.
The tenth embodiment of the invention includes an aspect wherein the temperature of the irrigant is between 46 degrees Celsius and 52 degrees Celsius.
An eleventh embodiment of the invention includes a method for treating bleeding in the urethra wherein an irrigant in the temperature range of 46 degrees Celsius to 52 degrees Celsius is motivated to lavage a patient's urethra via a catheter wherein the irrigant flows to the urethra via the catheter. An aspect of the eleventh embodiment includes a method wherein the irrigant flows from the urethra via the catheter.
The eleventh embodiment of the invention includes an aspect wherein the irrigant flow rate is between 2 cc/second and 12 cc/second.
A twelfth embodiment of the invention includes a system for treating bleeding in a urethra. The system includes an irrigant source, a heating apparatus connected to the irrigant source, wherein the heating apparatus is configured to heat an irrigant as the irrigant flows through the heating apparatus, and a treatment catheter having an irrigant outlet and an irrigant inlet located at a distal portion of a catheter body of the treatment catheter, wherein the irrigant outlet is located farther distally on the catheter body than the irrigant inlet.
The twelfth embodiment includes an aspect wherein the irrigant flow rate is between 2 cc/second and 12 cc/second.
The twelfth embodiment includes an aspect wherein the irrigant temperature is between 46 degrees Celsius and 52 degrees Celsius.
The twelfth embodiment includes an aspect wherein the system includes a pump.
The twelfth embodiment includes an aspect wherein the heating apparatus includes a heating element that heats the irrigant via a volumetric heating method. An aspect of the twelfth embodiment includes heating the irrigant via the application of radio-frequency energy.
The twelfth embodiment includes an aspect wherein the treatment catheter includes one or more sensors configured to sense temperature, flow rate, or other physical variables.
The twelfth embodiment includes an aspect wherein the heating apparatus includes one or more sensors configured to sense temperature, flow rate, or other physical variables.
The twelfth embodiment includes an aspect wherein a controller receives data feedback including temperature, flow rate, or other physical variables from sensors on the treatment catheter and/or the heating apparatus and uses the data feedback to control the heating apparatus.
The twelfth embodiment includes an aspect wherein a controller receives data feedback including temperature, flow rate, or other physical variables from sensors on the treatment catheter and/or the heating apparatus and uses the data feedback to control a pump.
For the purposes of describing and defining the present invention it is noted that the use of relative terms such as “substantially”, ‘generally”, “approximately” and the like, are utilized herein to represent an inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
The phrase “in one embodiment” is used repeatedly. The phrase generally does not refer to the same embodiment; however, it may. The terms “comprising,” “having” and “including” are synonymous; unless the context dictates otherwise. The following illustrations of various embodiments use particular terms by way of example to describe the various embodiments, but this should be construed to encompass and provide for terms such as “method” and “routine” and the like.
Exemplary embodiments of the present invention are described above. No element, act or instruction used in this description should be construed as important, necessary, critical or essential to the invention unless explicitly described as such. Although only a few of the exemplary embodiments have been described in detail herein and those skilled in the art will readily appreciate that many modifications are possible in these exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention.
Filing Document | Filing Date | Country | Kind |
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PCT/US19/60614 | 11/8/2019 | WO | 00 |
Number | Date | Country | |
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62757270 | Nov 2018 | US |