WO2016004114A1

WO2016004114A1 - Self-sealing infusion catheter

Info

Publication number: WO2016004114A1
Application number: PCT/US2015/038680
Authority: WO
Inventors: Manouchehr A. Miraki
Original assignee: Edwards Lifesciences Corporation
Priority date: 2014-07-01
Filing date: 2015-06-30
Publication date: 2016-01-07
Also published as: EP3164186A4; CA2949402A1; EP3164186A1

Abstract

Disclosed herein are self-sealing infusion catheter devices for introducing fluids into patient's bodies, and related methods. In some cases, the technologies disclosed herein can be used to introduce fluids into a patient' s body while the patient is undergoing surgery or recovering from surgery. In some cases, the technologies disclosed herein can be self-sealing to prevent blood from a patient's bloodstream from entering the distal end of a fluid delivery device or catheter. Fluids that can be introduced into a patient's body using the technologies disclosed herein include any fluid, including fluids comprising medications such as heparin, fluids comprising saline solutions, etc.

Description

SELF-SEALING INFUSION CATHETER FIELD

[001] The present disclosure relates generally to catheters and methods of introducing fluid into a patient' s body.

BACKGROUND

[002] Catheters are frequently used during and after surgical procedures to deliver fluids (e.g., fluids containing medication) to a patient's bloodstream. In some cases, an introducer is placed into the patient' s vasculature at the beginning of a procedure. After placement of the introducer, in some cases a single lumen catheter is inserted into the patient's vasculature through the introducer to deliver a fluid and/or medication into the patient's bloodstream. In known systems, a center core must be pulled out of the catheter to allow introduction of the fluid. In such systems, as the center core is pulled out of the catheter, blood can be drawn into, or can be allowed to flow into, the distal end of the catheter, where it can stagnate and/or clot, increasing the risk of serious complications during delivery of the fluid and the procedure generally.

SUMMARY

[003] Disclosed herein are fluid delivery devices for delivering a fluid into a patient's bloodstream. In some embodiments, a fluid delivery device for delivering a fluid into a patient's bloodstream comprises a main body portion comprising a proximal opening configured to receive the fluid and a distal opening configured to expel the fluid, a plug configured to seal the distal opening, and a biasing member, wherein when the fluid is not being introduced into the proximal opening, the biasing member biases the plug to seal the distal opening, and wherein when the fluid is being introduced into the proximal opening and exceeds a predetermined pressure, the plug can move away from the distal opening against the bias of the biasing member, thereby allowing the fluid to flow outwardly through the distal opening. [004] In some cases, the device further comprises an inner sealing member coupled to the biasing member, wherein when the fluid is not being introduced into the proximal opening, the biasing member biases the inner sealing member to seal the proximal opening, and wherein when the fluid is being introduced into the proximal opening and exceeds the predetermined pressure, the inner sealing member can move away from the proximal opening against the bias of the biasing member, thereby allowing the fluid to flow through the proximal opening and into the main body.

[005] In some cases, the inner sealing member is configured such that when the fluid exceeds the predetermined pressure, the inner sealing member moves closer to the distal opening than when the fluid is not being introduced into the proximal opening. In some cases, when the fluid is not being introduced into the proximal opening, the biasing member is compressed such that it has at least a residual amount of compression biasing the inner sealing member toward the proximal opening. In some cases, the plug comprises a tapered proximal portion having a proximal diameter and a distal diameter, wherein the distal diameter is larger than the proximal diameter. In some cases, the plug comprises a tapered distal portion having a proximal diameter and a distal diameter, wherein the proximal diameter is larger than the distal diameter.

[006] In some cases, the biasing member comprises a helical spring. In some cases, the biasing member comprises a bellows spring. In some cases, the device further comprises an elongated rod having a proximal end connected to the biasing member and a distal end connected to the plug, wherein the rod is configured to transfer the biasing force of the biasing member to the plug. In some cases, the plug and the inner sealing member are coordinated to seal and unseal the distal and proximal openings of the device, respectively, at substantially the same time.

[007] In some embodiments, a method of delivering a fluid into a patient's bloodstream comprises inserting a self-sealing infusion catheter into the patient's bloodstream to position a distal opening of the catheter at a delivery location, wherein the distal opening is sealed by a plug, the plug being biased to a sealing position by a biasing member, coupling a source of the fluid to a proximal opening of the catheter, actuating the source to deliver the fluid to the proximal opening of the catheter such that the fluid exerts a pressure against the biasing force of the biasing member, thereby moving the plug to an unsealed position such that the plug no longer seals the distal opening, and allowing the fluid to flow into the catheter through the proximal opening, through the catheter, and out of the catheter through the distal opening into the patient' s bloodstream.

[008] In some cases, prior to actuating the source, the proximal opening is sealed by an inner sealing member, and wherein actuating the source moves the inner sealing member to an unsealed position such that the inner sealing member no longer seals the proximal opening. In some cases, moving the inner sealing member comprises compressing the biasing member. In some cases, allowing the fluid to flow comprises allowing the fluid to flow through the biasing member. In some cases, actuating the source comprises increasing the pressure exerted by the fluid against the inner sealing member and thereby increasingly compressing the biasing member.

[009] In some cases, when the pressure exerted by the fluid against the inner sealing member exceeds a first threshold value, the inner sealing member no longer seals the proximal opening. In some cases, the method further comprises, upon delivery of a desired amount of the fluid, actuating the source of the fluid to decrease the pressure exerted by the fluid against the inner sealing member, thereby allowing the biasing member to expand, allowing the inner sealing member to move proximally back to its sealed position, and allowing the plug to move proximally back to its sealed position. In some cases, when the pressure exerted by the fluid against the inner sealing member falls below a second threshold value, the proximal opening is sealed by the inner sealing member and the distal opening is sealed by the plug. In some cases, the first threshold value and the second threshold value are substantially the same. In some cases, the source of the fluid is a first source of a first fluid, and the method further comprises uncoupling the first source of the first fluid from the proximal opening, and coupling a second source of a second fluid to the proximal opening. [010] The foregoing and other objects, features, and advantages of this technology will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[011] FIG. 1 illustrates a plug of a first embodiment of a self-sealing infusion catheter.

[012] FIG. 2 illustrates a coupling mechanism of the first embodiment of the self- sealing infusion catheter.

[013] FIGS. 3A and 3B illustrate a sealing member of the first embodiment of the self- sealing infusion catheter.

[014] FIG. 4 illustrates an end cap of the first embodiment of the self-sealing infusion catheter.

[015] FIG. 5 illustrates a housing of the first embodiment of the self-sealing infusion catheter.

[016] FIG. 6 illustrates a tube of the first embodiment of the self-sealing infusion catheter.

[017] FIGS. 7-11 illustrate a method of assembling the components illustrated in FIGS. 1-6 to form the first embodiment of the self-sealing infusion catheter.

[018] FIG. 12 illustrates an elongate tube and a cap of a second embodiment of a self- sealing infusion catheter.

[019] FIG. 13 illustrates an elongate shaft, a plug, and a sealing mechanism of the second embodiment of the self-sealing infusion catheter.

[020] FIG. 14 illustrates the sealing mechanism of FIG. 13 in greater detail.

[021] FIG. 15 illustrates the components of the second embodiment of the self-sealing infusion catheter of FIGS. 12 and 13 in a near-assembled configuration.

[022] FIG. 16 illustrates a source of a fluid coupled to the components of the second embodiment of the self-sealing infusion catheter of FIGS. 12 and 13. [023] FIGS. 17 and 18 show a distal end portion of the elongate tube of FIG. 12 and the plug of FIG. 13 in open and closed configurations, respectively.

[024] FIG. 19 illustrates another embodiment of a self-sealing infusion catheter not including a central shaft.

[025] FIG. 20 illustrates another embodiment of a self-sealing infusion catheter including a central tube.

[026] FIGS. 21A-21C illustrate another embodiment of a self-sealing infusion catheter.

DETAILED DESCRIPTION

[027] Disclosed herein are self-sealing infusion catheter devices for introducing fluids into patients' bodies, and related methods. In some cases, the technologies disclosed herein can be used to introduce fluids into a patient' s body while the patient is undergoing surgery or recovering from surgery. In some cases, the technologies disclosed herein can be self-sealing to prevent blood from a patient's bloodstream from entering the distal end of a fluid delivery device or catheter. Fluids that can be introduced into a patient's body using the technologies disclosed herein include any fluid, including fluids comprising medications such as heparin, fluids comprising saline solutions, etc.

[028] As used herein, the term "proximal" refers to a position, direction, or portion of a catheter device that is configured to be closer to a source of a fluid flowing through the device and into the body of a patient when the device is in use, and the term "distal" refers to a position, direction, or portion of a catheter device that is configured to be closer to the outlet of the fluid flowing through the device and into the body of a patient when the device is in use. Thus, for example, distal motion of the device can comprise motion further into the patient's blood vessel, while proximal motion of the device can comprise motion of the device out of the patient's blood vessel. The terms

"longitudinal" and "axial" refer to an axis extending in the proximal and distal directions, unless otherwise expressly defined. [029] FIGS. 1-6 illustrate components of a first embodiment of a self-sealing infusion catheter 100, which is shown assembled in FIG. 11. The catheter 100 generally comprises a plug or distal sealing member 102, a coupling mechanism 116, a proximal sealing member 128, an end cap 130, a housing 148, and a tube 160.

[030] FIG. 1 illustrates a cross-sectional side view of a plug 102 which can form a distal end portion of the assembled self-sealing infusion catheter 100. The plug 102 can include a main body having a distal end portion 104 and a proximal end portion 106. The distal end portion 104 can be tapered so that a diameter of the plug 102 decreases from an interface 112 between the distal end portion 104 and the proximal end portion 106 to a distal end 108 of the plug 102. The proximal end portion 106 can be tapered so that a diameter of the plug 102 decreases from the interface 112 to a proximal end 110 of the plug 102. The surfaces of the proximal end portion 106 and distal end portion 108 can be flat, curved, or have any other suitable configuration, and the surface of the plug 102 in the region of the interface 112 can be angled, curved, or have any other suitable configuration. In some cases, the plug 102 can have a shape such as a teardrop shape, an elliptical shape, or an egg shape.

[031] The plug 102 can have a generally circular cross section taken perpendicular to a longitudinal axis extending from its distal end 108 to its proximal end 110. The plug 102 can also include a cavity 114 formed in its proximal end portion 106. The cavity 114 can extend from an opening in the proximal end 110 to within the distal end portion 104. The plug 102 can be fabricated from any suitable material, such as a rigid plastic material.

[032] FIG. 2 illustrates a coupling mechanism 116 of the catheter 100. The coupling mechanism 116 can include a biasing member in the form of a spring 118 and a shaft 120. The biasing member is configured to provide a biasing force that urges the sealing member 128 and the plug 102 to respective closed positions sealing the proximal and distal openings of the catheter 100. The spring 118 can be a coiled, helically-shaped piece of elastic and/or resilient material, such as a helical metallic (e.g., stainless steel) spring. The shaft 120 can be coupled to a proximal end portion 122 of the spring 118, such as by an intermediate member 126, and can extend through the spring 118, such as along a central longitudinal axis of the spring 118, and beyond a distal end portion 124 of the spring 118. The features of the coupling mechanism 116 illustrated in the figures are not necessarily drawn to scale, and in some cases, the shaft 120 can be significantly longer than the spring 118. In some cases, the shaft 120 can extend beyond the distal end portion 124 of the spring 118 by at least, or by no more than, half the length of the spring 118. In some cases, the shaft 120 can extend beyond the distal end portion 124 of the spring 118 by at least, or by no more than, the length of the spring 118. In some cases, the shaft 120 can extend beyond the distal end portion 124 of the spring 118 by at least, or by no more than, one and a half times the length of the spring 118. In some cases, the shaft 120 can extend beyond the distal end portion 124 of the spring 118 by at least, or by no more than, twice, or three times, or four times, or five times, or ten times, or fifteen times, or twenty times the length of the spring 118.

[033] In alternative embodiments, other types of biasing members can be used. For example, the biasing member can comprise an elastomeric material, such as elastomeric tubing or a bellows spring (described below).

[034] FIGS. 3A and 3B illustrate side and end views, respectively, of a proximal sealing member 128 of the catheter 100. The sealing member 128 can comprise any suitable material, with silicone being one exemplary suitable material. The sealing member 128 can have a generally cylindrical shape, such that the sealing member 128 appears generally rectangular in a side view and generally circular in an end view.

[035] FIG. 4 illustrates a side view of an end cap 130, which can form a proximal end portion of the assembled self-sealing infusion catheter 100. The end cap 130 can include a main body having a distal end portion 132, an intermediate tapered portion 134, an intermediate neck portion 136, and a proximal ridge portion 138. Each of the distal end portion 132, tapered portion 134, neck portion 136, and ridge portion 138 can be hollow or annular, and thus a channel can extend through the end cap 130 from a proximal end 142 of the end cap 130 to a distal end 140 of the end cap. The distal end portion 132, tapered portion 134, neck portion 136, and ridge portion 138 can have generally circular cross sections taken perpendicular to a longitudinal axis extending from the distal end 140 to the proximal end 142.

[036] The distal end portion 132 can have a generally cylindrical shape. The tapered portion 134 can have a generally frustoconical shape having a diameter that tapers from an interface 144 between the tapered portion 134 and the distal end portion 132 to an interface 146 between the tapered portion 134 and the neck portion 136. The neck portion 136 can have a generally cylindrical shape. The ridge portion 138 can have a generally cylindrical shape having an outside diameter larger than an outside diameter of the neck portion 136. The ridge portion 138 can include one or more threads formed on its exterior surface. Together, the ridge portion 138, including its threads, and the neck portion 136 can form one part of a luer connection such that a source of a fluid (e.g., a syringe) can be coupled to the assembled catheter 100 in a fluid-tight fashion.

[037] FIG. 5 illustrates a cross-sectional side view of a housing 148 of the catheter 100. Housing 148 can comprise a proximal end portion 150 and a distal end portion 152 coupled to one another by an intermediate portion 154. Proximal end portion 150 can have an annular, generally cylindrical shape. Distal end portion 152 can have an annular, generally cylindrical shape having an outside diameter less than an outside diameter of the proximal end portion 150. Intermediate portion 154 can have an annular, generally cylindrical or disk shape, and can have an outside diameter about equal to the outside diameter of the proximal end portion 150 and an inside diameter smaller than or about equal to an inside diameter of the distal end portion 152. The proximal end portion 150 and distal end portion 152 can be coupled to opposing sides of the intermediate portion 154 such that an external surface of the proximal portion 150 is generally flush with an external surface of the intermediate portion 154, such that an outer portion 156 of the intermediate portion 154 couples the proximal end portion 150 to the distal end portion 152, and/or such that an inner portion 158 of the intermediate portion 154 forms a ridge 158 extending radially inwardly into a channel extending through the housing 148.

[038] FIG. 6 illustrates a cross-sectional side view of a tube 160 of the catheter 100. Tube 160 can have an annular, generally cylindrical shape. [039] FIGS. 7-11 illustrate a method of assembling the components illustrated in FIGS. 1-6 to form the self-sealing infusion catheter 100. FIG. 7 illustrates that the method can include coupling the sealing member 128 to the coupling mechanism 116, such as by adhesive or other suitable techniques. FIG. 8 illustrates that the method can further include positioning the coupling mechanism 116 such that the spring 118 is positioned within the proximal end portion 150 of the housing 148 and the shaft 120 extends through the intermediate portion 154 and the distal end portion 152 of the housing 148. The spring 118 has a diameter that is larger than the inside diameter of the intermediate portion 154 of the housing 148, such that the spring 118 can bear against a surface of the intermediate portion 154 and the spring 118 cannot be moved through the intermediate portion 154. The proximal end portion 122 of the spring 118 can extend beyond the proximal end portion 150 of the housing 148 such that the sealing member 128 is positioned outside of the housing 148.

[040] FIG. 9 illustrates that the method can further include positioning the end cap 130 over the proximal end 122 of the spring 118 and the sealing member 128 such that the sealing member 128 fits within the neck portion 136 of the end cap 130. An outside diameter of the sealing member 128 can be configured so that the sealing member 128 can fit within the neck portion 136 such that an external surface of the sealing member 128 engages an internal surface of the neck portion 136 to form a fluid-tight seal between the sealing member 128 and the neck portion 136. An inside diameter of the distal end portion 132 of the end cap 130 can be configured so that the distal end portion 132 can fit over the proximal end portion 150 of the housing 148, and the method can further include coupling the end cap 130 to the housing 148 in this configuration, such as by an adhesive or other suitable technique. In some cases, the spring 118 is compressed such that it has a residual amount of compression in this configuration, biasing the sealing member 128 toward the ridge portion 138.

[041] FIG. 10 illustrates that the method can further include positioning one end of the tube 160 within the distal end portion 152 of the housing 148. An outside diameter of the tube 160 can be configured so that the tube 160 can fit within the distal end portion 152 of the housing 148. An inside diameter of the tube 160 can be configured so that the shaft 120 of the coupling mechanism 116 can extend through the tube 160. A length of the tube 160 can be configured such that, with the components in this configuration, the distal end of the tube 160 is situated near to the distal end of the shaft 120. The length of the tube 160 can be configured such that, with the components in this configuration, the distal end of the shaft 120 extends beyond the distal end of the tube 160. The method can further include coupling the tube 160 to the distal end portion 152 in this configuration, such as by an adhesive or other suitable technique.

[042] FIG. 11 illustrates that the method can further include positioning the plug 102 such that a distal end portion of the shaft 120 is situated within the cavity 114 of the plug 102, and coupling the shaft 120 to the plug 102 in this configuration, such as by adhesive or other suitable technique, to form the self-sealing infusion catheter 100. In this configuration, the tapered shape of the proximal end portion 106 of the plug 102 can help the plug to form a seal at the distal end portion of the tube 160 as the plug 102 is brought into contact with the tube 160. The tapered shape of the distal end portion 104 of the plug 102 can help mitigate damage to native tissues as the catheter 100 is maneuvered through a patient's tissues. Together, the housing 148, end cap 130, and tube 160 can form a main body of the self-sealing infusion catheter 100.

[043] The self-sealing infusion catheter 100 can be used to introduce fluids into a patient's bloodstream. In one exemplary method, the catheter 100 can be maneuvered through a patient's tissues and/or vasculature to position the distal end portion of the tube 160 and the plug 102 at a delivery location. A source of fluid to be delivered (e.g., a syringe) can then be coupled to the end cap 130, such as by a luer connection making use of the associated components of the end cap 130 (described above). The source can then be actuated to deliver the fluid into the end cap 130 and push against the sealing member 128. As the pressure exerted by the fluid against the sealing member 128 increases, the spring 118 of the coupling mechanism 116 is compressed, the sealing member 128 moves distally toward the distal end portion 132 of the end cap 130, and the plug 102 moves distally away from the distal end portion of the tube 160. [044] In some cases, additional valves and/or sealing mechanisms can be coupled to the catheter 100 or incorporated therein. For example, in some cases, an additional valve can be incorporated into a luer connection as described above, incorporated into the spring 118, or incorporated into components external to the catheter 100. In some cases, such an additional valve can further help to seal the catheter 100 against fluid leaks. In a specific embodiment, an additional valve can be a duck bill valve, which can seal around a syringe introduced into the catheter 100.

[045] When the pressure exerted by the fluid exceeds a first threshold value, the spring 118 is compressed to the extent that the sealing member 128 is no longer situated within the neck portion 136 of the end cap 130 and the fluid can flow past the sealing member 128, through the housing 148 and the spring 118, through the tube 160, and out of the distal end portion of the tube 160. Upon delivery of a desired amount of fluid, the source of the fluid (e.g., the syringe) can be actuated to decrease the pressure exerted by the fluid against the sealing member 128. As the pressure exerted by the fluid against the sealing member 128 decreases, the spring 118 of the coupling mechanism 116 expands, the sealing member 128 moves proximally toward the neck portion 136 of the end cap 130, and the plug 102 moves proximally toward the distal end portion of the tube 160. When the pressure exerted by the fluid falls below a second threshold value, the sealing member 128 can re-enter and become situated within the neck portion 136 to seal the proximal end of the catheter 100 and the plug 102 can re-enter and become situated within the distal end portion of the tube 160 to seal the distal end of the catheter 100. In many cases, the first and second threshold values can be the same or about the same. In some cases, however, the first threshold value can be greater than the second threshold value, for example, in cases where the pressure exerted by the fluid against the sealing member 128 is resisted by friction between the sealing member 128 and the neck portion 136. The source of the fluid can then be disconnected from the catheter 100. In this configuration, the spring 118 can remain in compression (e.g., it can have the residual amount of compression, as described above) to ensure that the sealing member 128 remains within the neck portion 136 to prevent the catheter from leaking, and the plug 102 can prevent any native tissues or fluids such as blood from entering the tube 160 from the patient.

[046] In some cases, the self-sealing infusion catheter 100 can be used to introduce a plurality of fluids into a patient's bloodstream sequentially. For example, after disconnecting the source of the fluid from the catheter 100 as described above, a source of a second fluid can be coupled to the catheter 100 and the process of introducing the fluid and disconnecting the source can be repeated to introduce the second fluid. In some cases, the self-sealing infusion catheter can be used to introduce third, fourth, and/or additional fluids into a patient's bloodstream in this manner. In some cases, the catheter 100 can be used to introduce a first fluid comprising heparin into a patient's bloodstream, and then introduce a second fluid comprising saline into the patient's bloodstream.

[047] FIGS. 12-18 illustrate components of another embodiment of a self-sealing infusion catheter 200. The catheter 200 generally comprises an elongate tube 202, a cap 208, a shaft 218, a sealing mechanism 224, and a plug 226. FIG. 12 illustrates an elongate tube 202 having a proximal end portion 204 and a distal end portion 206. In some cases, the elongate tube 202 can be a 5F single lumen tube. The proximal end portion 204 of the elongate tube 202 can be coupled to an adapter or cap 208, and the distal end portion 206 of the elongate tube 202 can have an opening or port (not shown) formed therein. The cap 208 can comprise a main body 210 having a notch 212 formed therein, a proximal neck portion 214, and a proximal rim portion 216. The notch 212 can allow the cap 208 to be coupled to an introducer device. The cap 208 can have an opening or port (not shown) and the elongate tube 202 can be coupled to the cap 208 such that an opening in the proximal end of the tube 202 (not shown) is in fluid communication with the opening in the cap 208. The elongate tube 202 can be coupled to the cap 208 by an adhesive or other suitable technique.

[048] FIG. 13 illustrates an elongate shaft, or wire, 218 having a proximal end portion 220 and a distal end portion 222. The proximal end portion 220 of the shaft 218 can be coupled to a sealing mechanism 224 (more clearly shown in FIG. 14) and the distal end portion 222 of the elongate shaft 218 can be coupled to a plug 226 such as by adhesive or other suitable techniques. The plug 226 can have a shape similar to that of plug 102, such that it has a proximal tapered portion to help seal the distal end portion 206 of the tube 202, and a distal tapered portion to help reduce trauma to native tissues when the catheter is introduced into a patient's body. FIG. 14 illustrates that the sealing mechanism 224 can include a distal support element 228, which is functionally similar to intermediate portion 154. A biasing member in the form of a spring 230 can be coupled to a proximal surface of the distal support element 228 and can extend proximally away from the support element 228. The spring 230 can be a hollow, bellows-shaped piece of elastic material, such as a hollow, bellows-shaped plastic spring. The elongate shaft 218 can extend through an opening (not shown) in the distal support element 228 and through the hollow spring 230, and can be coupled to a proximal end of the spring 230 (not shown), such as by adhesive or other suitable techniques.

[049] The sealing mechanism 224 can further include an annular proximal portion 232, which can be rigidly coupled to the distal support element 228 by one or more intermediate elements 234. The annular proximal portion 232 and intermediate elements 234 are functionally similar to the proximal end portion 150 of the housing 148 and the end cap 130. The proximal portion 232 can include a relatively wide opening 236, a relatively narrow neck 238, a relatively wide locking portion 240, a tapered portion 242, and external threads 244. The tapered portion 242 and threads 244 are functionally similar to the tapered portion 134 and threads of the end cap 130. The threads 244 can form one part of a luer connection such that a source of a fluid (e.g., a syringe) can be coupled thereto in a fluid-tight fashion. The proximal end of the spring 230 can be coupled to a sealing member (not shown) situated within the tapered portion 242 of the sealing mechanism 224, and the spring 230 can bias the sealing member toward the relatively narrow proximal end portion of the tapered portion 242 such that an external surface of the sealing member engages an internal surface of the tapered portion 242 to form a fluid-tight seal between the sealing member and the tapered portion 242, thereby sealing the sealing mechanism 224. In some cases, the spring 230 is compressed such that it has a residual amount of compression in this configuration, biasing the sealing member into the tapered portion 242.

[050] FIG. 15 illustrates the catheter 200 in a near-assembled configuration. FIG. 15 illustrates that a method of assembling the catheter 200 can include passing the plug 226 through the tube 202 until the sealing mechanism 224 is proximate to the cap 208. The cap 208 can then be moved proximally until the rim portion 216 passes over the relatively wide opening 236 and is situated and seated within the neck 238, such that a fluid-tight seal is formed between the cap 208 and the sealing mechanism 224. In some embodiments, the cap 208 can be coupled to the sealing mechanism 224 using an adhesive or other suitable technique to improve the seal between the two components. Together, the tube 202, cap 208, and the sealing mechanism 224 can form a main body of the self-sealing infusion catheter 200.

[051] The self-sealing infusion catheter 200 can be used to introduce fluids into a patient's bloodstream. In one exemplary method, the catheter 200 can be maneuvered through a patient's tissues and/or vasculature to position the distal end portion 206 of the tube 202 and the plug 226 at a delivery location. FIG. 16 illustrates that a source of fluid to be delivered (e.g., a syringe) 246 can then be coupled to the sealing mechanism 224, such as by a luer connection making use of the associated components of the sealing mechanism 224 (described above). The source 246 can then be actuated to deliver the fluid into the sealing mechanism 224 and push against the sealing member (not shown). As the pressure exerted by the fluid against the sealing member increases, the spring 230 of the sealing mechanism 224 is compressed, the sealing member moves distally toward the distal support element 228 of the sealing mechanism 224, and the plug 226 moves distally away from the distal end portion 206 of the tube 202, as shown in FIG. 17.

[052] When the pressure exerted by the fluid exceeds a first threshold value, the spring 230 is compressed to the extent that the sealing member is no longer situated to seal the sealing mechanism 224 and the fluid can flow past the sealing member, through the sealing mechanism 224, through the tube 202, and out of the distal end portion 206 of the tube 202. Upon delivery of a desired amount of fluid, the source of the fluid (e.g., the syringe) 246 can be actuated to decrease the pressure exerted by the fluid against the sealing member. As the pressure exerted by the fluid against the sealing member decreases, the spring 230 of the sealing mechanism 224 expands, the sealing member moves proximally into the tapered portion 242 of the sealing mechanism 224, and the plug 226 moves proximally toward the distal end portion 206 of the tube 202, as shown in FIG. 18.

[053] When the pressure exerted by the fluid falls below a second threshold value, the sealing member can re-enter and become situated within the tapered portion 242 to seal the proximal end of the catheter 200 and the plug 226 can re-enter and become situated within the distal end portion 206 of the tube 202 to seal the distal end of the catheter 200. In many cases, the first and second threshold values can be the same or about the same. In some cases, however, the first threshold value can be greater than the second threshold value, for example, in cases where the pressure exerted by the fluid against the sealing member is resisted by friction between the sealing member and the tapered portion 242. The source of the fluid 246 can then be disconnected from the catheter 200. In this configuration, the spring 230 can remain in compression (e.g., it can have the residual amount of compression, as described above) to ensure that the sealing member remains within the tapered portion 242 to prevent the catheter from leaking, and the plug 226 can prevent any native tissues or fluids such as blood from entering the tube 202 from the patient.

[054] FIG. 21 A illustrates another embodiment of a self-sealing infusion catheter 500. The catheter 500 generally comprises a plug or distal sealing member 502, a coupling mechanism 516, a proximal sealing member 528, an end cap 530, a housing 548, and a tube 560, which are functionally similar to the respective components of the catheter 100, with the following differences. In catheter 500, the proximal sealing member 528 is not directly coupled to the coupling mechanism 516, and is coupled to the end cap 530 in the position shown in FIG. 21A. FIGS. 21B and 21C illustrate side and end views, respectively, of the proximal sealing member 528 of the catheter 500. As shown in FIGS. 21A-C, the proximal sealing member 528 has a slit 562 at its center. The slit 562 can be a very narrow cut through the entire thickness of the sealing member 528. The proximal sealing member 528 can comprise any suitable material, with synthetic latex being one exemplary suitable material.

[055] The self-sealing infusion catheter 500 can be used to introduce fluids into a patient's bloodstream. In one exemplary method, the catheter 500 can be maneuvered through a patient's tissues and/or vasculature to position the distal end portion of the tube 560 and the plug 502 at a delivery location. A source of fluid to be delivered (e.g., a syringe) can then be coupled to the end cap 530, such as by a luer connection. The source of the fluid can include a distal projection or tip which can extend through the slit 562 of the proximal sealing member 528 and contact a proximal end portion of the coupling member 516 when the source is coupled to the end cap 530. The tip of the source can be configured such that when the source is coupled to the end cap 530, the tip pushes against the coupling member 516, compressing the spring 518 and moving the plug 502 distally away from the distal end portion of the tube 560.

[056] In some cases, the sealing member 528 can form a fluid-tight seal around the tip of the source of the fluid when the tip extends through the sealing member 528. The source can then be actuated to deliver the fluid through the tip of the source into the end cap 530, through the catheter 500, and out of the distal end portion of the tube 560 into the patient' s bloodstream. In an alternative embodiment, the sealing member 528 can act as a one-way valve and the source can be actuated to deliver the fluid from a portion of the source proximal to the sealing member 528, through the sealing member 528, through the catheter 500, and out of the distal end portion of the tube 560 into the patient's bloodstream. For example, the sealing member 528 can form a duck bill valve which can seal around the tip of the source to allow fluid to flow into the end cap 530 but prevent fluid from flowing out of the end cap 530.

[057] Upon delivery of a desired amount of fluid, the source of the fluid (e.g., the syringe) can be disconnected from the end cap 530, such that the tip of the source no longer extends through the sealing member 528 and no longer compresses the spring 518. When the source is disconnected from the end cap 530, the plug 502 moves proximally toward the distal end portion of the tube 560 to seal the distal end portion of the tube 560 and prevent fluid leaking into or out of the distal end of the catheter 500. Further, when the source is disconnected from the end cap 530, the sealing member 528 can form a fluid tight seal to seal the end cap 530 and prevent fluid leaking out of the proximal end of the catheter 500. When the source is disconnected from the end cap 530, the spring 518 can remain in compression (e.g., it can have a residual amount of compression, as described above) to ensure that the plug 502 can prevent any native tissues or fluids such as blood from entering the tube 560 from the patient.

[058] The technologies disclosed herein improve upon prior catheters and methods of introducing fluids into a patient' s body. In particular, the technologies disclosed herein can reduce or prevent introduction of blood into a distal end of a fluid introducing device, in order to reduce blood stagnation and/or clotting therein. For example, the technologies disclosed herein can include a biasing member (e.g., a spring) configured to provide a biasing force that urges a distal sealing member (e.g., a plug) to seal a distal end portion of a catheter when a fluid is not being introduced through the catheter. For example, in some alternative embodiments, a self-sealing infusion catheter comprises the same components as catheter 100, but does not include a proximal sealing member. Further, the biasing member can be configured to provide a biasing force that urges a proximal sealing member to seal a proximal end portion of the catheter when a fluid is not being introduced through the catheter. The technologies disclosed herein can also facilitate more rapid fluid introduction than prior technologies.

[059] FIG. 19 illustrates another embodiment of a self-sealing infusion catheter 300, which is similar to catheter 100 and includes an introducer tube 302 similar to tube 160, but which does not include a shaft similar to shaft 120 extending through the introducer tube 302 or a plug similar to plug 102 for sealing the end of the tube 302. In another alternative embodiment, a self-sealing infusion catheter is similar to catheter 200 and includes an introducer tube similar to tube 202, but does not include a shaft similar to shaft 218 extending through the introducer tube or a plug similar to plug 226 for sealing the end of the tube 202. These alternative embodiments offer simpler designs than catheters 100 and 200. [060] FIG. 20 illustrates another embodiment of a self-sealing infusion catheter 400. Catheter 400 is similar to catheter 100 and includes an introducer tube 402 similar to tube 160, but includes a tube 404 in place of shaft 120 and a plug 406 in place of plug 102. The tube 404 has at least one lumen 405 extending along its length and the plug 406 has at least one opening 407. Each of the lumen extending along the length of the tube 404 is in fluid communication with a respective opening in the plug 406, such that fluids or other materials can be passed through the lumen, out the openings, and into the patient's body. Each of the lumen is coupled to a controller unit at the proximal end of the catheter 400, which can control materials passing through the lumen, out the openings, and into the patient's body. In some cases, the catheter 400 allows multiple fluids to be introduced into the patient's body simultaneously. In some cases, the catheter 400 allows a guidewire to extend through the catheter and into the patient's body as a fluid is simultaneously introduced into the patient' s body. In another alternative embodiment, the catheter 400 is similar to catheter 200 rather than catheter 100, the tube 402 is similar to tube 202 rather than tube 160, the tube 404 is in place of shaft 218 rather than shaft 120, and the plug 406 is in place of plug 226 rather than plug 102.

[061] For purposes of this description, certain aspects, advantages, and novel features of the embodiments of this disclosure are described herein. The disclosed methods, apparatuses, and systems should not be construed as limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed embodiments, alone and in various combinations and subcombinations with one another. The methods, apparatuses, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed

embodiments require that any one or more specific advantages be present or problems be solved.

[062] Although the operations of some of the disclosed methods are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed methods can be used in conjunction with other methods.

[063] As used herein, the terms "a", "an" and "at least one" encompass one or more of the specified element. That is, if two of a particular element are present, one of these elements is also present and thus "an" element is present. The terms "a plurality of and "plural" mean two or more of the specified element. As used herein, the term "and/or" used between the last two of a list of elements means any one or more of the listed elements. For example, the phrase "A, B, and/or C" means "A," "B," "C," "A and B," "A and C," "B and C" or "A, B and C." As used herein, the term "coupled" generally means physically coupled or linked and does not exclude the presence of intermediate elements between the coupled items absent specific contrary language.

[064] In view of the many possible embodiments to which the principles disclosed herein may be applied, it should be recognized that the illustrated embodiments are only preferred examples and should not be taken as limiting the scope of the disclosed technology. Rather, the scope of the disclosed technology is at least as broad as the following claims. I therefore claim all that comes within the scope and spirit of these claims.

Claims

We claim:

1. A fluid delivery device for delivering a fluid into a patient's bloodstream, comprising:

a main body portion comprising a proximal opening configured to receive the fluid and a distal opening configured to expel the fluid;

a plug configured to seal the distal opening; and

a biasing member;

wherein when the fluid is not being introduced into the proximal opening, the biasing member biases the plug to seal the distal opening; and

wherein when the fluid is being introduced into the proximal opening and exceeds a predetermined pressure, the plug can move away from the distal opening against the bias of the biasing member, thereby allowing the fluid to flow outwardly through the distal opening.

2. The fluid delivery device of claim 1 , further comprising an inner sealing member coupled to the biasing member;

wherein when the fluid is not being introduced into the proximal opening, the biasing member biases the inner sealing member to seal the proximal opening; and

wherein when the fluid is being introduced into the proximal opening and exceeds the predetermined pressure, the inner sealing member can move away from the proximal opening against the bias of the biasing member, thereby allowing the fluid to flow through the proximal opening and into the main body.

3. The fluid delivery device of claim 2, wherein the inner sealing member is configured such that when the fluid exceeds the predetermined pressure, the inner sealing member moves closer to the distal opening than when the fluid is not being introduced into the proximal opening.

4. The fluid delivery device of claim 3, wherein when the fluid is not being introduced into the proximal opening, the biasing member is compressed such that it has at least a residual amount of compression biasing the inner sealing member toward the proximal opening.

5. The fluid delivery device of any one of claims 1-4, wherein the plug comprises a tapered proximal portion having a proximal diameter and a distal diameter, wherein the distal diameter is larger than the proximal diameter.

6. The fluid delivery device of any one of claims 1-5, wherein the plug comprises a tapered distal portion having a proximal diameter and a distal diameter, wherein the proximal diameter is larger than the distal diameter.

7. The fluid delivery device of any one of claims 1-6, wherein the biasing member comprises a helical spring.

8. The fluid delivery device of any one of claims 1-6, wherein the biasing member comprises a bellows spring.

9. The fluid delivery device of any one of claims 1-8, further comprising an elongated rod having a proximal end connected to the biasing member and a distal end connected to the plug, wherein the rod is configured to transfer the biasing force of the biasing member to the plug.

10. The fluid delivery device of any one of claims 2-9, wherein the plug and the inner sealing member are coordinated to seal and unseal the distal and proximal openings of the device, respectively, at substantially the same time.

11. A method of delivering a fluid into a patient's bloodstream, comprising: inserting a self-sealing infusion catheter into the patient's bloodstream to position a distal opening of the catheter at a delivery location, wherein the distal opening is sealed by a plug, the plug being biased to a sealing position by a biasing member;

coupling a source of the fluid to a proximal opening of the catheter;

actuating the source to deliver the fluid to the proximal opening of the catheter such that the fluid exerts a pressure against the biasing force of the biasing member, thereby moving the plug to an unsealed position such that the plug no longer seals the distal opening; and

allowing the fluid to flow into the catheter through the proximal opening, through the catheter, and out of the catheter through the distal opening into the patient' s bloodstream.

12. The method of claim 11, wherein prior to actuating the source, the proximal opening is sealed by an inner sealing member, and wherein actuating the source moves the inner sealing member to an unsealed position such that the inner sealing member no longer seals the proximal opening.

13. The method of claim 12, wherein moving the inner sealing member comprises compressing the biasing member.

14. The method of claim 13, wherein allowing the fluid to flow comprises allowing the fluid to flow through the biasing member.

15. The method of claim 13 or claim 14, wherein actuating the source comprises increasing the pressure exerted by the fluid against the inner sealing member and thereby increasingly compressing the biasing member.

16. The method of claim 15, wherein when the pressure exerted by the fluid against the inner sealing member exceeds a first threshold value, the inner sealing member no longer seals the proximal opening.

17. The method of claim 16, further comprising, upon delivery of a desired amount of the fluid, actuating the source of the fluid to decrease the pressure exerted by the fluid against the inner sealing member, thereby allowing the biasing member to expand, allowing the inner sealing member to move proximally back to its sealed position, and allowing the plug to move proximally back to its sealed position.

18. The method of claim 17, wherein when the pressure exerted by the fluid against the inner sealing member falls below a second threshold value, the proximal opening is sealed by the inner sealing member and the distal opening is sealed by the plug.

19. The method of claim 18, wherein the first threshold value and the second threshold value are substantially the same.

20. The method of claim 18 or claim 19, wherein the source of the fluid is a first source of a first fluid, and wherein the method further comprises:

uncoupling the first source of the first fluid from the proximal opening; and coupling a second source of a second fluid to the proximal opening.