The present disclosure relates generally to medical devices used to provide compression and cooling to a vascular puncture or wound site as well as related systems and methods. More particularly, some embodiments of the present disclosure relate to endothermic compression devices, systems, and methods used to provide compression and cooling at a surgical site, including surgical sites located on the torso.
The embodiments disclosed herein will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. These drawings depict only typical embodiments, which will be described with additional specificity and detail through use of the accompanying drawings in which:
The components of the embodiments as generally described and illustrated in the figures herein can be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure but is merely representative of various embodiments. While various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The phrase “coupled to” is broad enough to refer to any suitable coupling or other form of interaction between two or more entities, including mechanical and fluidic interaction. Thus, two components may be coupled to each other even though they are not in direct contact with each other.
The phrase “fluid communication” is used in its ordinary sense and is broad enough to refer to arrangements in which a fluid (e.g., a gas or a liquid) can flow from one element to another element when the elements are in fluid communication with each other. Relatedly, “fluidly connect” is used herein to refer to an action or process of establishing a connection that provides fluid communication.
The term “fluid” is used in its broadest sense, to refer to any fluid, including both liquids and gases as well as solutions, compounds, suspensions, etc., which generally behave as fluids.
The term “compression” is used to define a compressive force or pressure applied to a portion of a patient over an area. The compression level may correlate to a pressure within an inflatable component of a compression device. The compression level may also correlate to a volumetric size or shape of an inflatable component. The compression level may also correlate to a downward force of the compression device.
The term “inflation” refers to the condition of an expandable fluid container. An increase of inflation correlates to an increase in fluid content within the container or to the volumetric size of the container. The inflation fluid may be compressible or non-compressible. The inflation level may or may not correlate to an internal pressure.
In some instances, surgery may cause some internal and/or external bleeding at or near the surgical site. This may lead to unwanted blood loss, development of hematoma, or other undesired outcomes. Thus, control of bleeding and/or establishing hemostasis may be part of a variety of treatments and procedures. In some instances, application of compression and/or cooling at an incision site may reduce the amount of bleeding and establish hemostasis after surgery. These measures can each reduce the diameter of blood vessels at and around the site, where such reduction is accomplished mechanically by compression, and/or via vasoconstriction induced by cooling.
The placement of pacing devices, such as a pacemaker or defibrillator, within a patient may include surgical creation of a pocket to receive the pacing device. Such a pocket may be formed in the tissue under the patient's skin on the torso of the patient, for example on the upper part of the patient's chest near the pectoral muscle and/or collarbone. In some instances, the external incision associated with creation of the pocket may be between one and three inches long. Creation of the pocket may cause internal and/or external bleeding and, in some instances, application of compression and/or cooling to the surgical site may reduce or otherwise aid in controlling the bleeding.
In some therapies, a pacing device may be located adjacent or near the subclavian or brachial vein and may include one or more pacemaker leads extending to the heart through the vasculature, such as through one of the subclavian or brachial veins. Again, the pacing device may also be disposed within a pocket in the tissue of the patient. Surgical incisions and tissue removal may thus create a surgical or incision site, which may also be referred to herein as the compression site, as application of compression with cooling may aid in controlling bleeding of the surgical or incision site after surgery.
Certain embodiments described herein facilitate the application of cooling with or without pressure to promote hemostasis at a torso surgical site. However, the present disclosure is not so limited; the application of cooling to promote hemostasis may be applied at access sites involving arteries and veins in various vasculature access points in a patient's body. Therefore, though specific examples in the disclosure below may refer to applying cooling to a torso surgical site, the embodiments of the present disclosure may be directed to other sites, such a patient's arm, wrist, hand, leg, or foot. For example, the embodiments of the present disclosure may be configured to promote hemostasis at a femoral artery access site, or at a radial artery access site.
The compression member 102 may include a window 116 to facilitate visual observation of the compression site when the compression member 102 is in place. As shown in
The inflatable bladder 112 may define a fluid-tight interior that allows it to be inflated by introduction of a fluid into the interior. The inflatable bladder 112 may comprise a material that extends around the entire interior, or the bladder material may be joined to the underside of the top plate 114 so as to define the interior. The inflatable bladder 112 may be configured so as to provide compression to a compression site when the inflatable bladder 112 is at least partially inflated. The inflatable bladder 112 may comprise a flat sheet or a pre-formed three-dimensional shape. The inflatable bladder 112 may be flexible and non-stretchable or flexible and stretchable. The inflatable bladder 112 may be transparent or translucent to facilitate visible observation of a compression site through both the window 116 and the inflatable bladder 112.
In addition to compression, the inflatable bladder 112 can also provide cooling to the compression site when the inflatable bladder 112 is at least partially inflated. In accordance therewith, the inflatable bladder 112 may be configured to hold a coolant solution that can assume a temperature that facilitates an absorption of heat from the compression site that results in cooling of said site. The valve 108 may be configured to facilitate injection of the coolant solution into the interior, and also withdrawal and replacement of the coolant solution. The valve 108 may be further configured for fluid communication with a delivery device or other source of coolant solution, as further described below.
The compression member 102 may include one or more features that indicate the current temperature of the bladder 112 and/or coolant solution, and thereby indicate the state of cooling provided to the compression site. In some embodiments, as illustrated in
In various embodiments, the temperature indicator may comprise a thermochromic feature in which the current temperature is indicated by the indicator's color or a change in temperature is indicated by a transition from one color to another color. In some embodiments, the temperature indicator is configured to indicate at least two temperature-related states of the coolant solution. Two such states may respectively be lower and higher than a target temperature. In some cases the target temperature may signify a transition point between a cooling state and a non-cooling state. A cooling state may comprise coolant solution temperatures that are sufficiently lower than that of the compression site so that heat will tend to move from the compression site into the coolant solution. Accordingly, the non-cooling state can comprise coolant solution temperatures at or above the point of thermoneutrality between the coolant solution and the compression site. A thermochromic indicator so configured may be able to assume a color in response to one of these temperature ranges and thereby indicate the corresponding state. The other state may be indicated by the absence of that color. For example, a thermochromic temperature indicator may assume a color to signify a cooling state in response to coolant solution temperatures at or below a target temperature of about 85° F., and may likewise not display said color when coolant solution temperature exceeds said target temperature.
In some embodiments, the thermochromic indicator may be further configured to assume at least two colors, wherein the indicator assumes a first color in response to one state and a second color in response to the other state. In a thermochromic temperature indicator capable of assuming more than two colors, the additional colors may reflect additional states or transitions between states. For example, a first color may indicate coolant solution temperatures that are effective for achieving hemostasis of the compression site, a second color may indicate coolant solution temperatures that are ineffective for this purpose, and a third color may indicate an intermediate range of temperatures over which limited cooling will occur but some further action (e.g., replacing the coolant solution or compression device) is needed to avoid loss of hemostasis.
In some embodiments the temperature indicator may include other features that indicate one or more temperature states. Nonlimiting examples include text, numbers, symbols, a scale bar, and a geometric pattern. In the case of text, numbers, and symbols, a single one of any of these may be used to indicate a temperature, or a plurality such as a series of numbers may be used to indicate multiple temperatures or a temperature range.
Each strap of the plurality of straps 106 may have the same length or the straps 106 may be of different lengths. In some embodiments, the length of one or more straps may be sufficient to extend around or partially around the torso of the patient. Each strap 106 may comprise a free end and may be coupled to the compression member 102 at a fixed end. The straps 106 may be generally elongate in shape, i.e., having a greater longitudinal length than width. The width may vary along the length of the strap 106. For example, in the illustrated embodiment, the width is narrower in a middle portion and wider at both the free end and the fixed end of each strap 106. Other shapes and designs of the straps 106 are likewise within the scope of this disclosure.
The plurality of straps 106 may be coupled to the compression member 102 such that each strap 106a, 106b, 106c, and 106d may pivot or rotate around the compression member 102. In other words, the straps 106 may be configured such that they may extend away from the compression member 102 at an adjustable direction or angle.
The compression device 200 may comprise a tube 222 coupled to the compression member 202 such that the tube 222 is in fluid communication with the inflatable bladder 212 at one end. The tube 222 may be coupled to the compression member 202 at a location toward an outer edge of the inflatable bladder 212 so as to not obstruct visibility through the window 216. A valve 208 may be coupled to the other end of the tube 222 so that the valve 208 is in fluid communication with the inflatable bladder 212. The tube 222 may provide flexibility between the valve 208 and the bladder thus providing for easier connection of an inflation fluid source 224 to the inflatable bladder 212. As shown, the compression member 202 may also comprise a temperature indicator 210 as described above.
As shown in the top view in
In some embodiments, a system for applying cooling and compression to a site on a body region of a subject provides for using a coolant solution in conjunction with an endothermic compression device. As illustrated in
In some cases, effective establishment or maintenance of hemostasis at a surgical site may depend upon the ability to initiate compression and cooling promptly after attaching the compression device to the patient. In some embodiments, a system for applying cooling and compression to a site on a body region of a subject may comprise a compression device, a coolant delivery device, and material(s) for making a coolant solution. The material(s) can comprise an endothermic material, that is, a material that is soluble in a liquid and lowers the temperature of the liquid as it dissolves. The endothermic material may be a solid material. In some embodiments, the coolant delivery device may be pre-loaded with a solid endothermic material from which a coolant solution may be made as needed. In some embodiments, the endothermic material may be pre-loaded in the inflatable bladder.
The endothermic material may be selected to produce a coolant solution having a desired temperature. In some embodiments, the coolant solution achieves a temperature that is therapeutically effective in achieving or maintaining hemostasis in the compression site, either alone or in combination with compression. The therapeutically effective temperature may depend in part upon the nature and location of the compression site. For example, a surgical site on the torso, such as a pocket for a pacemaker or defibrillator, may involve multiple smaller blood vessels, while other sites (e.g., a radial artery puncture site, or a femoral artery puncture site) may involve one or a few larger vessels. As such, different combinations of pressure and temperature may be indicated for these two types of compression sites. The cooling temperature is preferably at or near the lowest temperature that does not present a risk of injury to tissues in the compression site. For example, it is preferred that the coolant solution does not freeze upon formation so as to avoid tissue injury and also to preserve a degree of flexibility of the inflatable bladder. The coolant solution may also be configured so as not to reach temperatures below the freezing point of water. In some embodiments, the coolant solution assumes a temperature upon formation of about 33° F. to about 55° F., or more particularly about 35° F. to about 45° F. In some embodiments, the coolant solution remains within a temperature range of about 33° F. to about 65° F. for about 15 minutes to about 120 minutes, or about 15 minutes to about 60 minutes. In some embodiments, the temperature persists with this range for about 20 minutes to about 40 minutes.
The temperature of the coolant solution upon formation can be based on a number of parameters, including the heat of solution of the endothermic material, the selection and relative amounts of component compounds of the endothermic material, the particular liquid used as a solvent, and the rate of dissolution of the endothermic material. Any or all of these parameters may be selected and adjusted to determine the cooling properties of the coolant solution. In some embodiments, pellet or particle size may be selected to provide a particular rate of dissolution. The material may have a distribution of pellet or particle sizes having a selected mean pellet or particle size. And in some instances, the material may be present in a form in which substantially all pellets or particles are of a selected size.
Endothermic materials for use in accordance with the present disclosure may comprise one or more of ammonium nitrate, silver nitrate, urea, biuret, ammonium chloride, potassium nitrate, ammonium perchlorate, potassium chlorate, potassium perchlorate, potassium chloride, calcium ammonium nitrate, calcium nitrate tetrahydrate. In an embodiment, the endothermic material comprises at least about 55 wt % urea.
The endothermic material may further comprise one or more additives to confer desired physical and/or chemical properties. In some embodiments, the endothermic material further includes one or more dissolution accelerants including, but not limited to, potassium chloride. In particular embodiments, the endothermic material comprises a mixture of urea and potassium chloride. In an embodiment, the endothermic material comprises about 70 wt % to about 90 wt % urea and about 10 wt % to about 30 wt % potassium chloride. In some embodiments, the endothermic material includes one or more anticaking agents. Anticaking agents that may be used include, but are not limited to, calcium silicate, magnesium hydroxide carbonate, sodium aluminosilicate, sodium ferrocyanide and potassium ferrocyanide. In another embodiment, the endothermic material includes an additive such as silica gel.
As shown in
As shown in
Some embodiments of an endothermic compression device may employ other means of cooling a compression site to which the device is applied. In some embodiments, the compression member may include a cooling element that provides cooling in conjunction with the inflatable bladder. In certain embodiments, the compression member includes a thermoelectric cooling element, also termed a Peltier cooler. A Peltier cooler is a solid-state active heat pump in which heat is transferred from one side to the other when current is applied to the cooler. The amount of heat transferred can be linearly related to the amount of current powering the Peltier cooler. Through the use of two plates on opposite sides of the cooler, the Peltier cooler can transfer the heat from one plate (the “cold surface”) to the other (the “hot surface”), whereby the cold surface can function as a cooling surface. It should be understood that the modifiers “hot” and “cold” as used herein in reference to these two surfaces are intended to represent relative temperatures at each end of a temperature gradient, and should not be construed as referring to specific temperature value unless expressly stated otherwise.
An exemplary embodiment is shown in cross-section view
The Peltier cooler 532 can be located within a pocket 538 situated on the underside of the compression member 502, for example formed in the material of the inflatable bladder 512. In another aspect, the Peltier cooler 532 can have a rigid structure that facilitates compression of a surgical site. For example, inflation of the inflatable bladder 512 can exert a downward force onto the Peltier cooler 532, which is in turn translated into a compressive force applied to the compression site over the surface area of the Peltier cooler 532. In certain embodiments, the Peltier cooler 532 can be removable from the pocket 538 such that it may be sanitized and/or reused.
The Peltier cooler 532 may be configured to provide cooling within a selected temperature range. The temperature range provided can depend on physical characteristics of the Peltier cooler 532, such as the dimensions and materials of the plates; and on the structure of its semiconductor array. The temperature range can also depend on the voltage applied to the cooler. In some embodiments, the Peltier cooler 532 can be activated to assume temperature at the cold surface 536 of about 33° F. to about 55° F., or more particularly about 35° F. to about 45° F. In some embodiments, a temperature indicator is functionally connected to the cold surface so as to indicate the temperature of the cold surface.
In some embodiments, the Peltier cooler is electrically connected to a control circuit configured for activation of the Peltier cooler by connecting the cooler to a voltage source. The control circuit can be further configured to keep the temperature of the cold surface of the cooler within a selected temperature range e.g., by controlling the timing and magnitude of the activating voltage. In some embodiments, the voltage source is a battery.
Various methods of use and treatment are within the scope of this disclosure. While certain examples of methods of treatment are described herein, methods within the scope of this disclosure include any subset of the steps recited and re-ordering of the steps as described.
An exemplary method of use of an endothermic compression device to apply compression with cooling to a compression site may comprise one or more of the following steps or processes. A practitioner may place the compression member on a body region and position the compression member over a compression site identified in said body region. The practitioner may view the compression site through the window while positioning and aligning the compression member. The practitioner may then secure the compression device to the body region with the securement system. The practitioner may then inflate the inflatable bladder with one or more inflation fluids. The inflatable bladder may be initially uninflated, partially inflated, or substantially fully inflated, or the inflatable bladder may initially contain a vacuum.
In various embodiments, inflation may be accomplished at least in part by injecting a volume of coolant solution into the interior of the bladder to provide cooling to the compression site. In some embodiments, inflation can comprise using a coolant delivery device such as described above, where the chamber of said device contains coolant solution. In an embodiment, the coolant delivery device is a syringe with a volume of coolant solution contained in the barrel. More particularly, the practitioner may fluidly connect the coolant delivery device to the inflatable bladder, e.g., via a valve if the bladder is so equipped, and inject a volume of the coolant solution into the inflatable bladder. In some embodiments, the procedure further comprises making a coolant solution by providing a coolant delivery device containing an amount of endothermic material such as described above, and introducing a volume of liquid solvent into the coolant delivery device to combine with the endothermic material. In an embodiment, the coolant delivery device is a syringe with an amount of endothermic material contained in the barrel. Liquid solvent can be added to the endothermic material by withdrawing the syringe plunger while the barrel is in fluid contact with a source of said solvent.
The practitioner may use an endothermic compression device as described herein to provide cooling therapy comprising a temperature or range of temperatures for a period of time. In accordance with some embodiments, this may be accomplished by at least partially inflating the bladder with a coolant solution having such a temperature and leaving the compression device in place for the desired therapy duration or while the coolant solution temperature remains within the target range. The temperature or range of temperatures may be selected to be therapeutically effective in achieving or maintaining hemostasis in the compression site, either alone or in combination with compression. Therapeutically effective temperatures may depend in part on the nature and location of the compression site. In some embodiments, cooling is provided by maintaining the coolant solution in the inflatable bladder within a temperature range of about 33° F. to about 65° F. for about 15 minutes to about 120 minutes, or about 15 minutes to about 60 minutes. In some embodiments, the temperature range is about 40° F. to about 60° F. In some embodiments, the temperature range is maintained for about 20 minutes to about 40 minutes.
The practitioner may ascertain the coolant solution temperature state by observing the temperature indicator, and may monitor the temperature state as the coolant solution gradually warms. If the temperature indicator indicates that the coolant solution is warming such that its temperature may exceed the desired temperature range before the desired time has expired, the practitioner may extend the cooling time by withdrawing the coolant solution from the bladder and replacing it with a quantity of coolant solution, e.g., freshly made coolant solution, having a temperature in the desired temperature range.
In accordance with some embodiments, providing cooling therapy comprising a temperature or range of temperatures for a period of time can comprise using an endothermic compression device having a compression member equipped with a thermoelectric cooling element such as a Peltier cooler. This method can comprise activating the Peltier cooler so as to initiate cooling of its cold side, for example, by applying a voltage to the Peltier cooler via electrical connections. In some embodiments, the Peltier cooler is activated via a control circuit configured to maintain cooling at or near the temperature or within the range of temperatures. For example, cooling may be maintained within a temperature range of about 33° F. to about 65° F. for about 15 minutes to about 120 minutes, or about 15 minutes to about 60 minutes. In some embodiments, the temperature range is about 40° F. to about 60° F. In some embodiments, the temperature range is maintained for about 20 minutes to about 40 minutes. In some embodiments, maintaining cooling temperature may comprise adding to or replacing a fluid in the inflatable bladder so as preserve the bladder's function as a heat sink for the hot surface.
Any methods disclosed herein include one or more steps or actions for performing the described method. The method steps and/or actions may be interchanged with one another. In other words, unless a specific order of steps or actions is required for proper operation of the embodiment, the order and/or use of specific steps and/or actions may be modified. Moreover, sub-routines or only a portion of a method described herein may be a separate method within the scope of this disclosure. Stated otherwise, some methods may include only a portion of the steps described in a more detailed method.
Reference throughout this specification to “an embodiment” or “the embodiment” means that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, the quoted phrases, or variations thereof, as recited throughout this specification are not necessarily all referring to the same embodiment. Similarly, it should be appreciated by one of skill in the art with the benefit of this disclosure that in the above description of embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure.
Without further elaboration, it is believed that one skilled in the art can use the preceding description to utilize the invention to its fullest extent. The claims and embodiments disclosed herein are to be construed as merely illustrative and exemplary, and not a limitation of the scope of the present disclosure in any way. It will be apparent to those having ordinary skill in the art, with the aid of the present disclosure, that changes may be made to the details of the above-described embodiments without departing from the underlying principles of the disclosure herein. In other words, various modifications and improvements of the embodiments specifically disclosed in the description above are within the scope of the appended claims. Moreover, the order of the steps or actions of the methods disclosed herein may be changed by those skilled in the art without departing from the scope of the present disclosure. In other words, unless a specific order of steps or actions is required for proper operation of the embodiment, the order or use of specific steps or actions may be modified. The scope of the invention is therefore defined by the following claims and their equivalents.
This application claims priority to U.S. Provisional Patent Application No. 63/244,122, filed Sep. 14, 2021, and titled ENDOTHERMIC COMPRESSION SYSTEMS AND METHODS, which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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63244122 | Sep 2021 | US |