Patent Application
20210330902
The present invention relates to the field of powder delivery, particularly dry powder delivery, and more particularly to dry powder delivery to internal patient sites. The powder may offer different medicinal benefits including but not limited to hemostasis, wound healing, localized medicine delivery, localized tissue response, and other interactions with the tissue the powder interacts with.
Internal tissue may bleed during a non-invasive surgical procedure or from disease on internal tissues. These situations make blood loss and visibility (during surgery) important concerns. During some procedures, a hemostatic agent may be applied to the affected bodily tissue to stop the bleeding, at least until a more robust method can be used to permanently stop the bleeding. These agents are often delivered as dry hemostatic powders. Many of these powders are known to agglomerate, or have agglomerative properties, making it more difficult to propel the powder through a lumen of an endoscope for delivery to a treatment site inside the body. For example, the lumen may become blocked by the material, especially if there is liquid within the lumen. As a result, some effective hemostatic agents may have disadvantages, for example, by requiring continuous delivery. Some of these powders are described in U.S. Pat. Nos. 6,992,233; 9,598,504; and 10,137,219 (Drake); and U.S. Pat. No. 8,703,176 (Zhu).
U.S. Pat. No. 9,629,966 (Ji) discloses an internal dry powder delivery system through a working channel of an endoscopic cannula for directly applying the powder form medication to an internal tissue/organ site. The system includes an elongated tubular delivery channel and a powder supply device for producing pressurized gas mixing with the dry powder for feeding to form a mixture of dry powder and pressurized gas delivering to an internal tissue/organ site through the delivery channel via endoscopic cannula. The system is asserted to ensure a smooth powder release by preventing liquid from accumulation at the tip of the delivery channel and offers physicians a new powder form drug delivery method via endoscope. Also, it offers new minimal invasive application by directly and precisely applying the powder format drug to the internal sites of human gastrointestinal organ via endoscope to achieve hemostasis, anti-inflammation, anti-ulcer and anti-tumor treatment, etc. Powder is injected by manually increasing pressure in the powder containing elements to eject powder into the delivery channel.
U.S. Pat. Nos. 9,205,207; 8,827,980; and 8,721,582 (Ji) disclose an internal dry powder delivery system through a working channel of an endoscopic cannula for directly applying the powder form medication to an internal tissue/organ site. The system includes an elongated tubular delivery channel and a powder supply device for producing pressurized gas mixing with the dry powder for feeding to form a mixture of dry powder and pressurized gas delivering to an internal tissue/organ site through the delivery channel via endoscopic cannula. The system is asserted to ensure a smooth powder release by preventing liquid from accumulation at the tip of the delivery channel and offers physicians a new powder form drug delivery method via endoscope. Also, it offers new minimal invasive application by directly and precisely applying the powder format drug to the internal sites of human gastrointestinal organ via endoscope to achieve hemostasis, anti-inflammation, anti-ulcer and anti-tumor treatment, etc. The system of this patent displayed technical issues addressed by U.S. Pat. No. 9,629,966
U.S. Pat. No. 8,118,777 (Ducharme) provides systems and methods suitable for delivering a therapeutic agent to a target site. The systems generally comprise a container for holding a therapeutic agent, and a pressure source configured to be placed in selective fluid communication with at least a portion of a reservoir of the container. In one embodiment, fluid from the pressure source is directed through a first region of the container in a direction towards a second region of the container. The fluid then is at least partially redirected to urge the therapeutic agent in a direction from the second region of the container towards the first region of the container and subsequently towards the target site. In alternative embodiments, the fluid from the pressure source may be directed through the second region of the container in a direction towards the first region of the container.
Published U.S. Patent Application Document No. 20180001067 (Christakis) disclosed implementations of a delivery device and method are disclosed. One implementation is a delivery device comprising a flow chamber with an inlet port for receiving a fluid flow in the flow chamber, and an outlet port for exiting a material from the flow chamber. The flow chamber may include a formation portion in which a suspension of the material is formed, and a collection portion that directs the suspension toward and/or into the outlet port. An amount of the material may collect in the collection portion adjacent the outlet port. The device may further comprise an insertion port for permitting insertion of the material in the flow chamber, and/or a pusher operable to move the amount of material through the outlet port. Related devices and methods also are disclosed. Pressure in the powder storage area is manually increased to eject powder into a flow stream.
Improved hemostatic powder delivery system to internal wounds and sores are needed. All documents cited herein are incorporated by reference in their entireties.
Published US Patent Document No. 20070286892 (Herzberg) discloses compositions and methods for preventing or reducing postoperative ileus and gastric stasis. Such compositions include a combination of a carrier component and a bioactive component which acts to prevent or reduce post-operative ileus. Such methods include administering a therapeutically effective amount of the composition directly to the serosal surfaces of the gastrointestinal and other visceral organs.
Although powder coating is an unrelated field of technology, the application of powders to surfaces, as in Published US Patent Application Document 20060097071 (Robideaux) should be considered.
A method and apparatus deliver dry, flowable medicinal powder into a gas flow stream by gravity delivery within a body of the apparatus. The medicinal powder is then carried with the gas out of the apparatus into an elongated delivery tube inserted into a patient. Delivery of the powder into the gas flow stream creates a bolus of powder and air which becomes more uniformly distributed as it passes through the elongated delivery tube.
While in this invention description, the preferred powder delivered to the patient is described as hemostatic, powders with other medicinal benefit can also be delivered to a patient with the same device. Other powders may include but are not limited to: mucoadhesive polymers, wound healing polymers, powders that act as neutralizing agents for the acidic gastric environment, proton pump inhibitors, powdered biologics, anti-microbial agents, etc. Powders may be delivered individually or as mixtures with any other powder as actives or as inert carrier. For the sake of clarity and brevity, the term hemostatic generally will be used to further describe the invention, however the invention can apply to any of the other medicinal powders as described above.
The invention includes a method and apparatus to deliver dry, flowable hemostatic powder into a gas flow stream by gravity delivery within a body of the apparatus. The hemostatic powder is then carried with the gas out of the apparatus into an elongated delivery tube inserted into a patient. Delivery of the powder into the gas flow stream creates a bolus of powder and gas which becomes more uniformly distributed as it passes through the elongated delivery tube.
The invention also includes a method of delivering dry powder, preferably a dry, flowable hemostatic powder to an internal operation site or wound site of mammals. The term flowable refers to the fact that, if a 15 gram quantity of a specific free-flowing powder is placed in a funnel with 30 degree sloping sides (relative to the central axis of the funnel) that is sealed at its top most diameter, and contains a orifice of dimension 0.150 inches or more at it smallest diameter and this diameter is maintained for a length no more than 2 times the orifice size, the powder will completely flow out the funnel under the force of gravity emptying the funnel and the only gas that flows back into the funnel comes into the lower diameter end of the funnel in the opposite directions as the powder flow. The powder flow may be momentarily interrupted when the gas flows into the funnel. The powder drops in packets, slugs, bolus or other interrupted flow into the mixing (air and powder mix) below the cartridge.
The method further includes the steps of:
(a) extending a distal end of the elongated tubular delivery channel to a position that an emitting opening of said delivery channel is adjacent to said internal operation site or wound site. The term “extending” of the elongated tubular delivery channel is determined by medical procedural demands, and not by technical necessity in the process. The channel (a tube, cannula, etc.) may be extended before attachment to the hand-held device or may be extended after the channel has been attached to the hand-held device. The hand-held device will not be activated until after the channel has been inserted and the channel engaged with the hand-held device. Most preferably, if the tubular delivery channel is to be inserted into the working channel of an endoscope and liquids may be present in this working channel, the channel is to be first attached to the hand-held device and gas flow initiated prior to insertion into the working channel, thus using the positive pressure of the flowing gas to prohibit the possible intrusion of liquid into the lumen of the channel.
The method continues with (b) providing a hand-held application device comprising a handle end and a forward end connected to a proximal end of the elongated tubular delivery channel, generating a conveying gas flow containing pressurized gas to mix with dry powder (preferably a hemostatic powder, but other medicinal powder materials such as antibiotics, scaffolding materials, adhesive, etc.). The gas should of course be medically acceptable within a patient, and likely would be medical grade, pure carbon dioxide or medical grade air provided from a piped source or pressurized gas cannister. The hand-held device further includes a receptor (a seat, a capture support shaped to receive a bottom section of a gravity feeding powder cannister) for a neutral pressure particulate dry hemostatic powder gravity feeding cartridge, and an internal gas flow path from the handle end to the proximal end and passing under the receptor. The cannister is supported and removably secured into the cartridge receptor. The support and securement may be a tight fit, a snap-in connection, a threaded screw-in connection or sliding or gripping lock-unlock connector. The cannister has a opening on a bottom or downward facing end of the cannister, the opening (hole) being large enough to allow powder to flow by gravity downwardly solely by the action of gravity. The size of the hole will depend upon the rate of flow desired and the need to address different gravity flow properties of the powder. Typically, the opening, when cleared of any intended blockage or coverage, should have an internal diameter of at least 4 mm and may be up to 12 mm inside diameter for the opening. The average size of particles in the powder, surface properties and shape of the powder particles shall influence the particle flow properties of the powder out of the cartridge through any funneling shapes in the delivery of the powder into an area where the particles and gas mix. Any optimization of dimensions in the gravity fed path would be modified based on the properties of the particles in the powder.
The process continues by (c) engaging (inserting, connecting, placing, snapping, locking, etc.) the neutral pressure particulate dry hemostatic powder gravity feeding cartridge onto the receptor. It must be clearly understood that the powder flows downwardly by force of gravity, and pressure within the cartridge has no function in delivering powder into the mixing area. This can be understood by analyzing gas pressure during activity of the system. In one embodiment of this invention, the only source of gas entry into the cartridge is upwardly from the tubular delivery channel. The gas flows upwardly into the chamber sporadically and intermittently after powder has been fed out of the cartridge. The removal of powder therefor lowers gas pressure in the cartridge. The reduced pressure is alleviated by intermittent and sporadic bubbling or “burping” of bubbles or boli of gas upward out of the tubular delivery channel. As the gas pressure of these bubbles or boli of gas can never exceed the pressure of flowing gas within the tubular delivery tube, and the pressure in the cartridge is lower than the pressure in the tubular delivery tube when powder is flowing out, the gas pressure in the cartridge will always be at a lower gas pressure than, or at best equal to the pressure in the tubular delivery tube.
In another embodiment of this invention, a gas conduit connects the gas flow channel in the immediate vicinity of where the powder enters the gas flow path to the powder chamber and therefore as powder gravity flows out of the powder chamber, gas may flow through this conduit to replace the volume of gas lost and thus may approximately equalize the gas pressure in the cartridge with that of the gas flow path.
The process then continues by (d) providing a gas conveying tube connected to the flow path at the handle end of the hand-held application device; and (e) providing gas under pressure to the gas conveying tube to cause gas flow through the internal gas flow path and under the receptor. The gas pressure and flow is sufficient to pick up and carry the particles in the powder dropped into that internal gas flow path. That gas pressure, as stated above, can never be lower than the gas pressure in the cartridge, as the only source of additional gas in the cartridge, cannot increase the gas pressure in the cartridge to a pressure higher than that in the internal gas flow path. Therefore, gas pressure in the cartridge can not force powder into the internal gas flow path.
For this reason, in the process (f) only the force of gravity drops the dry hemostatic powder from the opening in the bottom of the cartridge into the internal gas flow path through the receptor.
The gas flowing through the internal gas flow path (g) carries the dropped dry hemostatic powder in the internal gas flow into the proximal end of the elongated tubular delivery channel; and
Then (h) delivers the dropped dry hemostatic powder carried in the internal gas flow path to the internal operation site or wound site to assist clotting of blood at the operation site or wound site through the elongated tubular delivery channel.
The method may be continued wherein the dropped dry hemostatic powder is dropped into the internal gas flow while gas pressure above the dry hemostatic powder in the cartridge is lower than gas pressure within the internal gas flow path. As previously described, the gas pressure in the cartridge is reduced by delivering the dropped dry hemostatic powder into the internal gas flow path creating an increased pressure differential between the gas pressure above the dry hemostatic powder in the cartridge and the gas pressure within the internal gas flow path, and intermittently gas in the internal gas flow path will form a bolus of gas and flow up through the dry hemostatic powder in a bottom section of the cartridge to reduce the pressure differential between the gas pressure above the dry hemostatic powder in the cartridge and the gas pressure within the internal gas flow path, without creating a new gas pressure differential between the gas pressure above the dry hemostatic powder in the cartridge and the gas pressure within the internal gas flow path where the gas pressure in the cartridge never exceeds the gas pressure in the internal gas flow path.
The dropped dry hemostatic powder is initially carried in the internal gas flow path at a point below the connector as a first bolus of dry hemostatic powder in gas separated by volumes of gas with a lower concentration of dry hemostatic powder than is present in the first bolus of dry hemostatic powder in gas.
The providing of gas under pressure to the gas conveying tube is initiated by a valve or stopcock that is attached to the hand held device or placed in the tubing between the hand held device and the pressurized gas source. There is a trigger within the handle end of the hand-holdable device which opens and closes an opening for hemostatic powder (by opening and closing the sliding pin) to be gravity fed from the cartridge while there is gas flow from the handle end towards the coupling elements and the distal end of the hand-holdable device. The hemostatic powder drops into flow of gas through the tubing. The drop of hemostatic powder into the tubing is not a steady state process, even if the gas flow is steady. The powder drops in batches or boli into a capture or mixing area directly below or nearly below the cartridge. The gas flow picks up the batches of hemostatic powder, and carries each packet in the gas flow. As elsewhere described herein, these packets get more dispersed within the air flow, and even if a perfect distribution within the gas flow (perfectly dispersed or suspended particles), the degree of dispersion is acceptable for application to a wound site at the distal end of the hand-holdable device,
In the method, the first bolus of dry hemostatic powder in gas is believed to at least partially merges with the volumes of gas with a lower concentration of dry hemostatic powder after entering the elongated tubular delivery channel.
The inventions also include an apparatus for delivering dry hemostatic powder to an internal operation site or wound site of mammals including:
In the apparatus, the neutral pressure particulate dry hemostatic powder gravity feeding cartridge is dry-flowable powder engaged with the receptor for the neutral pressure particulate dry hemostatic powder gravity feeding cartridge and the receptor is positioned at a relatively upper side of the hand-holdable device.
In the apparatus, a surface of the hand-holdable device opposite to the receptor for the neutral pressure particulate dry hemostatic powder gravity feeding cartridge is a movable stopper that when open allows gravity feeding of dry hemostatic powder from the neutral pressure particulate dry hemostatic powder gravity feeding cartridge into the internal gas flow path, and when the stopper is closed, prevents gravity feeding of dry hemostatic powder from the neutral pressure particulate dry hemostatic powder gravity feeding cartridge into the internal gas flow path.
In an alternative embodiment the moveable stopper is not needed in the apparatus.
Instead the hand-held device can be rotated upon its central gas flowing axis to control powder flow, so that when the cartridge is below the gas flowing axis, gravity holds the powder within the cartridge. When the hand-held device is rotated 180 degrees from this closed position, the cartridge is elevated to allow gravity to feed the powder into the internal gas flow path. When the powder chamber is directly above the internal gas flow path, powder will flow under the force of gravity. As the device is rotated about the central axis of the flow path, the powder chamber will no longer be over the opening leading to the flow path and powder flow will cease. Powder flow can then be reinitiated by reversing this rotation.
In yet another alternative embodiment, the moveable stopper can be configured with a tapered design that extends upward and decreases in diameter as the stopper penetrates into the powder chamber such that the available area for powder flow is dependent on the extent that the trigger controlling the moveable stopper is depressed, thus allowing the metering of the powder flow by the user operating the trigger.
In yet another alternative embodiment, the moveable stopper can be configured with a stepped design that extends upward into the powder chamber with decreasing dimension in stepwise fashion as the stopper penetrates into the powder chamber such that the available area for powder flow is dependent on the extent that the trigger controlling the moveable stopper is depressed, thus allowing the metering of the powder flow by the user operating the trigger.
A greater appreciation of the invention will be gained by reference to the Figures.
Any flowable hemostatic powder within a range of size and flow properties may be used. An example of a preferred hemostatic powder is NexStat® Plus topical hemostat powder is an all-natural, plant-based polysaccharide in an easy-to-use applicator ideal for treating bleeding from Endoscopic Sinus Surgeries. NexStat® Plus topical hemostat powder meets ISO 10993 biocompatibility requirements and contains no animal tissue or other bovine agents.
Another hemostatic powder spray is Hemospray® (Cook Medical, Winston-Salem, N.C., USA) as a new method and material for managing gastrointestinal bleeding. Hemablock® (HemaBlock LLC, Edina, Minn., USA) is another hemostatic powder that can be used in a wide range of sterile and non-sterile procedures. Arista™ AH is a 100% plant based absorbable surgical hemostatic powder derived from purified plant starch. The ability of Arista™ AH (Davol subsidiary of C. R. Bard, Warwick, R.I., USA) lies in its microporous polysaccharide hemispheres, a patented blood clotting technology. Other hemostatic powders may be used, with only minor adjustments in opening and tube sizes and variations in air carrying pressure.
Although specific dimensions and materials may be described above, they are specific information within the generic scope of the present invention.
This application claims priority from Provisional U.S. Patent application Ser. No. 63/014,671, filed 23 Apr. 2020. That application is incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63014671 | Apr 2020 | US |
