US20070021770A1 - Apparatus and Method for Percutaneous Sealing of Blood Vessel Punctures - Google Patents

Abstract

A device for promoting hemostasis in a blood vessel puncture is employed with an introducer that accesses the puncture through an incision. The introducer has an open distal end positionable at the puncture, an external portion with an open proximal end, and an axial channel therebetween. The device includes a hollow catheter, dimensioned to pass through the introducer channel, having a distal end to which is attached an expansible compression element, which may be an inflatable balloon, a collapsible prong assembly, or a resilient foam pad. The compression element is collapsed when the distal end of the catheter is enclosed within the introducer. When the catheter and the introducer are located the desired distance from the puncture, the introducer is displaced axially relative to the catheter to expose the compression element to the subcutaneous tissue, whereupon the compression element is expanded. Pressure is applied to the compression element through the introducer to promote hemostasis by the compression of subcutaneous tissue adjacent the puncture. The device preferably includes a locator member passing into the blood vessel through the puncture. The locator member may be either a guide wire, or a hollow tube with a locating balloon, disposed near the portion of the tube insertable into the vessel. A dissolvable locating tip element, connected to the distal end of the catheter, may be used to maintain the position of the device while hemostasis takes place after the locator member is removed.

Description

CROSS-REFERENCE TO RELATED APPLICATION
• This application is a continuation-in-part of co-pending application Ser. No. 08/528,892; filed Sep. 15, 1995; issuing as U.S. Pat. No. 5,645,566.
FEDERALLY FUNDED RESEARCH OR DEVELOPMENT
• Not Applicable
BACKGROUND OF THE INVENTION
• The present invention relates generally to the field of apparatus and methods for sealing wounds in the blood vessels of humans or animals. More specifically, the invention relates to a guided vascular compression device for percutaneously sealing arterial or venous punctures subsequent to surgical procedures, by promoting in situ hemostasis.
• Ad A large number of medical therapeutic and diagnostic procedures involve the percutaneous introduction of instrumentation into a vein or artery. For example, percutaneous transluminal coronary angioplasty (PTCA), most often involving access to the femoral artery, is performed hundreds of thousands of times annually, and the number of other such vessel-piercing procedures performed, e.g., percutaneous coronary angiography and atherectomy, has exceeded two million per year.
• In each event, the closing and subsequent healing of the resultant vascular puncture is critical to the successful completion of the procedure. Traditionally, the application of external pressure to the skin entry site by a nurse or physician has been employed to stem bleeding from the wound until clotting and tissue rebuilding have sealed the perforation. In some situations, this pressure must be maintained for half at hour to an hour or more, during which the patient is uncomfortably immobilized, often with sandbags and the like. With externally applied manual pressure, both patient comfort and practitioner efficiency are impaired. Additionally, a risk of hematoma exists since bleeding from the vessel may continue until sufficient clotting effects hemostasis. Also, external pressure devices, such as femoral compression systems, may be unsuitable for patients with substantial amounts of subcutaneous adipose tissue, since the skin surface may be a considerable distance from the vascular puncture site, thereby rendering skin compression inaccurate and thus less effective.
• More recently, devices have been proposed to promote hemostasis directly at the site of the vascular perforation. One class of such puncture sealing devices features intraluminal plugs, as disclosed in U.S. Pat. No. 4,852,568—Kensey; U.S. Pat. No. 4,890,612—Kensey; U.S. Pat. No. 5,021,059—Kensey et al.; and U.S. Pat. No. 5,061,774—Kensey. This class of device is characterized by the placement of an object within the bloodstream of the vessel to close the puncture.
• Another approach to subcutaneous puncture closure involves delivery of tissue adhesives to the perforation site, as disclosed in U.S. Pat. No. 5,383,899—Hammerslag. Some likelihood exists of introducing the adhesive so employed disadvantageously into the bloodstream. U.S. Pat. No. 4,929,246—Sinofsky discloses the concept of applying pressure directly to an artery, and relies on the directing of laser energy through an optical fiber to cauterize the wound.
• Yet another proposed solution to obviate the reliance on skin surface pressure is disclosed in U.S. Pat. No. 5,275,616—Fowler, wherein a cylindrical plug is inserted along the shaft of a catheter segment extending from the skin surface to the blood vessel. The catheter is then removed so that the plug can expand as fluid is drawn into the plug from the vessel and surrounding tissue. Unless pressure is applied, however, bleeding may occur around the plug into the subcutaneous tissue. Another approach that similarly deposits a plug into the tissue channel is disclosed in U.S. Pat. No. 5,391,183—Janzen et al., which discloses a variety of plug delivery devices including threaded plug pushers and multilegged channels. As in the other disclosed methods for introducing a foreign plug into the incision, the Janzen et al. plug material, generally resorbable, is not removed from the patient once installed. Such permanent placement of foreign material into the body may result in inflammation or scar formation in the long term.
• Furthermore, many of the prior art devices rely on tactile sensation alone to indicate to the surgeon the proper placement of the puncture closing instrumentation, and may require upstream clamping of the blood vessel to reduce intraluminal pressure to atmospheric at the puncture site.
• As the foregoing description of the prior art demonstrates, none of the heretofore proposed solutions fulfills the need for a relatively simple, non-cautery apparatus and method for subcutaneously applying pressure directly to the vicinity of the vessel puncture by means of a pressure element that is removed from the patient once sealing of the puncture is achieved. There is a further need for a puncture sealing system that features use of instruments already in place at the access site so that the position for possible reentry is not lost, and the time required for the physician to change instrumentation is minimized. There is a still further need for a system that maintains pressure on the puncture site by lightweight mechanical means, thereby relieving the patient from the discomfort of external compression means, and freeing hospital personnel from constant surveillance of cumbersome external pressure structures for the duration of the hemostasis. There is also a need for a hemostatic device that can be effectively employed regardless of the thickness of the tissue between the skin and the puncture site, by applying localized pressure close to the puncture site, rather than remote, diffused pressure to the skin surface.
SUMMARY OF THE INVENTION
• It is an object of this invention to provide a method and apparatus for sealing post-surgical vascular punctures that overcome the foregoing deficiencies.
• It is a further object to apply pressure directly to the vicinity of the vascular puncture access site utilizing a subcutaneous pressure element that is removed permanently from the patient once hemostasis is achieved.
• It is another object to employ an introducer instrument already in place at the access site to minimize instrumentation changing time, and to maintain access during an initial clotting period to facilitate possible reentry.
• It is yet another object to maintain adequate hemostatic pressure on an adipose or fatty tissue layer above the puncture site in order to close the puncture naturally, to reduce the potential for pseudo-aneurysm formation, and to maintain such pressure by lightweight, non-labor intensive, mechanical means, thereby reducing patient discomfort.
• The present invention involves a method for sealing a puncture site in a blood vessel, and apparatus for performing that method, wherein use is made of an introducer sheath (commonly referred to in the medical community as an “introducer”) which is usually already in place inside the puncture site when a medical practitioner has completed a procedure that requires intravascular access. Locator means, preferably either a locator tube (having an inflatable locating balloon), or a standard guidewire, is passed through the introducer and into the lumen of the vessel. Alternatively, a dissolvable locating tip can be provided at the distal end of catheter. The locating tip is inserted into the lumen of the vessel, using a guidewire, and maintains the distal end of the catheter in its proper position in the puncture site.
• A semi-rigid catheter, including an expandable compression element at its distal end, and either two axial lumens (used in a compression balloon embodiment) or a single axial lumen (used in other embodiments), is inserted along the locator means fully into the introducer so that the expandable compression element at the distal end of the catheter is contained in an unexpanded state within the distal end of the introducer when the introducer is in a first or distal position relative to the catheter.
• The introducer and the catheter are partially withdrawn together (moved proximally) from the puncture site until a preferred location above the vessel is achieved, the relative axial positions of the introducer and the catheter remaining unchanged, so that the introducer remains in its first or distal position relative to the catheter. This location is chosen to provide for a layer of fatty tissue above the puncture site between the compression element and the vessel. The extent of partial withdrawal is determined by the tactile sense of the practitioner, aided by a marker on a locator tube for the embodiment employing a locating balloon as the locator means, or by fluoroscopic viewing of a contrast medium, for the embodiments employing a guidewire (with or without a dissolvable locating tip) as the locating means.
• When the location is achieved, the introducer is moved to a second or proximal position relative to the catheter until the expandable compression element is revealed and expanded to bear on the fatty tissue layer.
• In another embodiment, the expandable compression element comprises an expandable prong assembly including a resilient spanning sheet for compressing the fatty tissue layer. In still another embodiment, the expandable compression element comprises a foam pad element bearing directly on the fatty tissue layer upon expansion when deployed from the introducer.
• Once the compression element (balloon, prongs or foam tip) is in place, a lightweight holding arrangement is employed to maintain hemostatic pressure. The holding arrangement comprises an adhesive skin patch and fastener strips or bands bringing downward pressure on a sheath cuff clamped to the introducer. After an initial period of hemostasis, (approximately one to five minutes), the locator means (locator balloon tube or guidewire) is removed from the puncture and the apparatus. After another five to twenty-five minutes of pressure on the puncture, the expandable distal end element (compression balloon, prongs or foam) is collapsed, and the introducer and catheter are permanently removed from the patient.
• These and other features and advantages of the present invention will be more readily apparent from the Detailed Description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is an elevational view, partially in cross section, illustrating a first preferred embodiment of the present invention;
• FIG. 1A is an elevational view, partially-in cross section, illustrating the initial position in a puncture site of the distal portion of the apparatus ofFIG. 1;
• FIG. 1B is an elevational view, partially in cross section, illustrating the apparatus ofFIG. 1A in a preferred operational position;
• FIG. 1C is an elevational view, partially in cross section, illustrating the apparatus ofFIG. 1A with the compression balloon revealed and not yet inflated;
• FIG. 1D is a cross sectional view taken along lines1D-1D ofFIG. 1, illustrating the dual lumen configuration of a catheter element of the apparatus ofFIG. 1;
• FIG. 2 is an elevational view, partially in cross section, of a second preferred embodiment of the present invention, showing the compression mechanism of this embodiment in a retracted state near a vascular puncture site;
• FIG. 2A is a perspective view of the embodiment ofFIG. 2, showing the compression mechanism in an expanded state;
• FIG. 2B is a view similar to that ofFIG. 2, showing the a compression mechanism deployed, in its expanded state, at a vascular puncture site;
• FIG. 3 is an elevational view, partially in cross section, of a third preferred embodiment of the present invention, showing the compression mechanism of this embodiment in a retracted state near a vascular puncture site;
• FIG. 3A is a view, similar to that ofFIG. 3, illustrating the compression mechanism in an expanded state;
• FIG. 4 is a perspective view of a fourth preferred embodiment of the present invention;
• FIG. 4A is an elevational view, partially in cross section, illustrating the initial position in a puncture site of the introducer and guidewire elements of the apparatus ofFIG. 4;
• FIG. 4B is a view similar to that ofFIG. 4A, but showing a catheter contained within the introducer when the introducer is in a first axial position relative to the catheter;
• FIG. 4C is an elevational view, partially in cross section, illustrating the apparatus ofFIG. 4A in a preferred operational position;
• FIG. 4D is an elevational view, partially in cross section, illustrating the apparatus ofFIG. 4A with the compression balloon revealed and not yet inflated, the introducer having been moved to a second axial position relative to the catheter;
• FIG. 4E is a perspective view, partially in cross section, illustrating the compression balloon of the apparatus ofFIG. 4D in an inflated state;
• FIG. 4F is an elevational view, partially in cross section, illustrating the apparatus ofFIG. 4E with the guidewire element withdrawn;
• FIG. 5 is an elevational view, partially in cross section, illustrating a modification of the embodiment ofFIG. 1;
• FIG. 6 is an elevational view of a modification of the fourth preferred embodiment ofFIGS. 4 through 4F, having an optional dissolvable locating tip at the distal end of the catheter;
• FIG. 7 is an elevational view of the modified fourth preferred embodiment ofFIG. 6, showing the present invention deployed at a vascular puncture site, with the locating tip inserted into the lumen of a blood vessel;
• FIG. 8 is an elevational view of a modification of the third preferred embodiment ofFIGS. 3 and 3A, having an optional dissolvable locating tip; and
• FIG. 9 is an elevational view of an alternative form of a dissolvable locating tip.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• 1. Structure of the Apparatus
• A percutaneous blood vessel sealing device, or percutaneoushemostatic device10, which applies hemostatic sealing pressure directly to tissue adjacent a vascular puncture site, without employing implanted materials, is shown inFIG. 1.
• In each exemplary embodiment described herein, an introducer sheath (“introducer”)12, well known in the art, is present in anincision14 that extends from theskin surface16 to a blood vessel (artery or vein)18 of a patient at the site of ablood vessel puncture20. Theintroducer12 has normally been inserted previously to provide access to thevessel18 for instrumentation (not shown) used in performing a vascular procedure immediately preceding the need to seal thepuncture20. The initial position of anintroducer12 so inserted is most clearly illustrated inFIG. 4A, which shows a tapereddistal end22 of theintroducer12 at apuncture site24, inserted within avascular puncture20. Typically, theintroducer12 will have a size of approximately 7 French (2.3 mm in diameter), and a length of approximately 130 mm, although a size as large as 14 French (4.7 mm in diameter) may be used for larger punctures.
• A workingchannel26, best seen inFIG. 1D, extends axially from theproximal end28 of theintroducer12 through its tapereddistal end22. In the first preferred embodiment ofFIGS. 1 through 1D, ahollow locator tube30 extends coaxially through theintroducer12 and into thevessel18 through thepuncture20. Guided by thelocator tube30 into theintroducer working channel26 is asemi-rigid catheter32 having a catheterproximal end33, and a catheter distal end34 (FIG. 1A). Theintroducer12 is movable axially with respect to thecatheter32, and is disposed initially at a first axial position, or distal position, in which the catheterdistal end34 is enclosed or sheathed within thedistal end22 of theintroducer12.
• Thecatheter32 is a dual-lumen device having a first axial lumen36 (FIG. 1D) which encompasses thelocator tube30 when thecatheter32 is inserted into the workingchannel26 of theintroducer12. A secondaxial lumen38 is provided with an inflation orifice40 near its distal end, the inflation orifice communicating with the interior of acompression balloon42 that concentrically surrounds a portion of the length of thecatheter32 extending proximally from itsdistal end34. Thecompression balloon42 is initially enclosed, in an uninflated state, within thedistal end22 of theintroducer12, as illustrated inFIG. 1A. The opposite (proximal) end of the secondaxial lumen38 communicates with a compression balloon inflation port44 through aninflation tube45, as shown inFIGS. 1 and 4. Overall, thecatheter32 has an outer diameter sufficiently small to be freely insertable into theintroducer12, and a length that is greater than that of theintroducer12, i.e., in the range of about 130 mm to about 750 mm.
• At theproximal end28 of theintroducer12 is a well-known luer type lock fitting46 configured to mate with a catheter proximal end luer fitting48 when theintroducer12 and thecatheter32 are in a final operational position, as determined by manipulation of thelocator tube30, as will be described below. Thelocator tube30 has an inflatable intravascular locatingballoon50 at its distal end portion, shown inFIG. 1A in an uninflated state. The interior of the locatingballoon50 is in fluid communication with the hollow interior of thelocator tube30 through a suitable inflation orifice (not shown), as is well known in conventional balloon catheters and the like.
• Although the luer locks46,48 may be employed for both the locator balloon embodiment (FIGS. 1 through 1D) and for embodiments (described below) featuring expandable compression elements other than thecompression balloon42, a version using no luer locks will be described below that is specifically adapted for use with thecompression balloon42. Both the luer and non-luer versions are suitable for embodiments employing either theinflatable locating balloon50 or a guidewire locating means, to be described-below.
• Returning now toFIGS. 1A through 1C, a progression of locating positions for thedevice10 is illustrated.FIG. 1A shows thelocator tube30, having theuninflated locating balloon50 near its distal end, inserted into thevessel18 through theintroducer12 and thevascular puncture20. It is advantageous to construct thelocator tube30 so that a length of tube extends distally beyond the location of the locatingballoon50 into thevessel18 to facilitate re-access through thevascular puncture20, if required. The entire apparatus10 (including theintroducer12 and the catheter32) is in its initial position relative to the vessel; that is, thedistal tip22 of theintroducer12 is located adjacent to or within thepuncture20, while theintroducer12 is in its above-described first axial position or distal position relative to thecatheter32, in which the catheterdistal end34 and theuninflated compression balloon42 are enclosed within thedistal end22 of theintroducer12.
• FIG. 1B illustrates thedevice10 after the locatingballoon50 has been inflated by fluid introduced into it via thelocator tube30. The entire device10 (including theintroducer12 and the catheter32) has been go partially withdrawn from thepuncture site24 in the direction of the arrow52 (i.e., in the proximal direction), to a “preferred operational position”, in which the locatingballoon50 is lodged against aninterior wall54 of thevessel18. Theintroducer12 remains in its first or distal position, in which the portion of thecatheter32 carrying theuninflated compression balloon42 is enclosed within thedistal end22 of theintroducer12.
• InFIG. 1C, theintroducer12 has been moved axially, relative to thecatheter32, in the direction of the arrow52 (i.e., proximally), to its second axial position, or proximal position. The movement of theintroducer12 to this second or proximal position uncovers theuninflated compression balloon42.
• The compression stage of thedevice10 is illustrated next inFIG. 1. Thecompression balloon42, inflated via the second axial lumen38 (FIG. 1D), rests in an optimal position to effect natural hemostasis, viz., above alaminar portion56 of the fatty tissue adjacent thepuncture site24. An optimal distance from thevessel18 to the catheterdistal end34 is in the range of 2 mm to 10 mm. This distance will dispose a layer offatty tissue56 between thevessel18 and thecatheter32, minimizing the potential for pseudo-aneurysm. Theintroducer luer lock46 is shown engaged with thecatheter luer lock48, assuring that a holding force applied to theintroducer12 will be transmitted as well to thecatheter32. In addition, avisible marker band57 on the exterior of the locatingtubing30 may advantageously be provided to align the proximal ends of theintroducer12 and thecatheter32 in correspondence with the location of the distal ends22,34 thereof when thelocator balloon50 is lodged against theinner wall54 ofvessel18.
• Anadhesive skin patch58 with asheath cuff60 clamped onto the external portion of theintroducer12 to apply downward force (in the direction of thearrow62, i.e., distally) on theintroducer12 is shown inFIGS. 1 and 4. Fastener strips64 secure theadhesive patch58 to thesheath cuff60. The fastener strips64 may be elastic bands with suitable adhesive areas, or hook and loop strips (such as the type marketed under the trademark VELCRO) that adhere to areas of complementary material on thepatch58. Pressure maintained by theintroducer sheath cuff60 on thecatheter32 provides hemostatic pressure on thecompression balloon42 to bear on thetissue layer56 for a first period of time, whereupon the locatingtube30 is withdrawn (thelocator balloon50 having first been deflated), and a second period of time elapses, after which all instrumentation is removed from the patient as will be noted when the method for sealing thepuncture20 is described in detail below.
• Another embodiment of the present invention is illustrated inFIGS. 2, 2A, and2B, which show a collapsible prongassembly compression element66 attached to the catheterdistal end34. Theprong assembly66 is radially compressed or collapsed when enclosed within theintroducer12, when the introducer is in its first or distal position. Theprong assembly66 expands radially when theintroducer12 is partially withdrawn from the vessel18 (FIGS. 2A and 2B), by moving theintroducer12 to its second or proximal position in a manner similar to the partial withdrawal ofintroducer12 in the direction ofarrow52 as described previously in connection with the compression balloon embodiment.
• Theprong assembly66 comprises a plurality of spaced-apartresilient prongs68, the proximal ends of which are attached to thecatheter32, and the distal ends of which are attached to a collapsible spanning film sheet ordam70, shown expanded inFIGS. 2A and 2B. The sheet ordam70 allows the application of hemostatic pressure on thetissue56 above thevessel18. Acentral aperture72 in the sheet ordam70 permits the locator tube (not shown) to project through thecatheter32 into thevessel18 as described previously. Since there is no compression balloon to be inflated, a catheter with a singleaxial lumen36 is adequate for this application. Materials for the spanning sheet ordam70 may include polyurethane and polyethyleneterephthalate (PET).
• Still another embodiment of the invention is illustrated inFIGS. 3 and 3A, which show a foampad compression element74 attached to the catheterdistal end34. Thefoam pad element74 is compressed when enclosed within theintroducer12 when the introducer is in its first or distal position. The foampad compression element74 then expands when theintroducer12 is partially withdrawn from thevessel18, as shown inFIG. 3A, by moving theintroducer12 to its second or proximal position, as described above with respect to the first and second embodiments. Hemostatic pressure is similarly exerted on thetissue56 above thevessel18. Anaxial channel76 in thefoam pad74 permits the locator tube (not shown) to project through thecatheter32 into thevessel18, as described previously. As with the expanding prong embodiment above, since there is no compression balloon to be inflated, a catheter with a singleaxial lumen36 is adequate for this embodiment. Materials for thefoam pad74 may include various polymeric foams, such as polyurethanes, as are well-known in the art. Thefoam pad74 may be impregnated with a coagulant such as thrombin or protamine to effect local hemostasis.
• The foregoing embodiments, featuring both the luer locking of theintroducer12 with thecatheter32, and a variety ofexpandable compression elements42,66,74 at the catheterdistal end34, employ alocator tube30 with a locatingballoon50 to determine the optimal operational location for theapparatus10. In lieu of a locatingballoon50, aguidewire78 may be utilized for the location determination of theapparatus10, as illustrated inFIGS. 4 through 4F.
• InFIG. 4A, astandard guidewire78, typically 3 French (1 mm in diameter), shown coaxially located within theintroducer12, has adistal end82 extending out of the introducerdistal end22 into thepuncture20 of thevessel18.
• Thecatheter32 is shown inFIG. 4B having been inserted into theintroducer12 and guided to thedistal end22 of the introducer by theguide wire78. At thedistal end34 of thecatheter32 is a radiopaque marker84 for viewing under fluoroscopy, as shown inFIG. 4D.
• FIG. 4C shows an optimal location for catheterdistal end34, radiopaque contrast medium (not shown) having been introduced into thecatheter lumen36, and theapparatus10 having been partially withdrawn from thevessel18 in the direction of the arrow52 (i.e., proximally). An extravasation85 of the radiopaque contrast medium is shown marking the desired distance between thevessel18 and the catheterdistal end34, as will be explained when the method for sealing the puncture is described below.
• Theintroducer12 is shown inFIG. 4D having been moved, in the direction of thearrow52, to its second or proximal position to reveal theuninflated compression balloon42 in position for inflating.FIG. 4E illustrates theapparatus10 with thecompression balloon42 inflated and in place above thefatty layer56 to apply hemostatic pressure for a first period of time in order to effect initial closure ofpuncture site24.FIG. 4F shows theapparatus10 after theguidewire78 has been removed from theapparatus10 and pressure is applied for a second period of time to close thepuncture20.
• In analogous fashion, theguidewire78 and radiopaque positioning of an expandable compression element at thedistal end34 of thecatheter32 may be employed with the prong assembly and foam pad embodiments described above in connection with thelocator tube30. For introducing the radiopaque or contrast medium (not shown) into thecatheter lumen36, a standard hemostatic “Y”86 is used, as shown inFIG. 4. The “Y”86 has amain leg88 for receiving theguidewire78 into theaxial lumen36 of thecatheter32, while a side port90 of the “Y”86 is used for introducing the contrast medium into the same lumen.
• A modification of the first (compression balloon) embodiment of the present invention is shown inFIG. 5, where anapparatus110 has anintroducer112 having no luer connection with acatheter132. Since thecuff60 applies downward force in the direction of thearrow62 only to theintroducer112 and not to thecatheter132, the distal end122 of theintroducer112 must bear directly on thecompression balloon42 to exert hemostatic pressure on theballoon42. Although this modification is suitable only for the compression balloon embodiment of this invention, both thelocator tube30 and theguidewire78 may be utilized in this modification for optimal positioning of the catheterdistal end34.
• FIGS. 6 and 7 illustrate a modification of the fourth preferred embodiment (that ofFIGS. 4 through 4F). In accordance with this modification, a dissolvable or resorbable locatingtip element140 is fixed to thedistal end34 of thecatheter32, distally from thecompression balloon42. The locatingtip element140 is an elongate, tubular member, having a generally cylindricalmain portion142 and a tapereddistal end tip144. The diameter of the cylindricalmain portion142 is preferably about 1.3 to 4.0 mm, and the overall length of the locatingtip140 element is preferably about 1 to 4 cm, the dimensions of aparticular locating tip140 being selected in accordance with such factors as the dimensions and location of the puncture site, its “dwell time” (see below), and the preferences of the physician. The locatingtip140 element is hollow and open-ended to allow theguidewire78 to pass through it.
• The locatingtip element140 is preferably used in conjunction with locating means such as theguidewire78 or thelocator tube30. As shown inFIG. 7, the locatingtip element140 is dimensioned so that it can be inserted into theblood vessel lumen18 through thepuncture site20, and maintains the location of theapparatus10 during use, after theguidewire78 has been withdrawn (see below). The locatingtip element140 is made of a material that is biocompatibly (non-toxically) dissolved in the blood stream during a period of between about 10 and 60 minutes (the “dwell time”), during which time partial resorption of the material into the subcutaneous tissue results in the detachment of the locatingtip element140 from thecatheter32. The detachment leaves a portion of the locatingtip element140 outside of the blood vessel, to be completely dissolved into the subcutaneous tissue.
• Suitable materials for the locatingtip element140 may include, for example a number of well-known polymers, methyl cellulose, carboxymethyl cellulose, carbowaxes, and gelatin (particularly pigskin gelatin). Among the suitable polymers are polylactic glycolic acids, polyvinyl pyrrolidone, polyvinyl alcohol, polyproline, and polyethylene oxide.
• The dissolvablelocating tip element140 may be employed with other embodiments of the invention, particularly the compressible foam pad embodiment ofFIGS. 3 and 3A. In this embodiment, as shown inFIG. 8, afoam pad74′ is attached to thedistal end34 of thecatheter32, and has adistal end146. A dissolvablelocating tip element140′, of the type described above, is attached to, and extends distally from, thedistal end146 of thefoam pad74′.
• It will be appreciated that the dissolvable locatingtip element140,140′ may be modified and adapted for use as a locating tip for catheters and other devices that may be used in a wide variety of applications. For example, an alternative dissolvablelocating tip element150 is shown inFIG. 9. In this alternative form, the dissolvable locatingtip element150 comprises acylindrical portion152 attached to the distal end of a surgical instrument154 (e.g., a catheter). Projecting distally and coaxially from thecylindrical portion152 is a slendertubular portion156, terminating in a tapereddistal end tip158. The distal end of the cylindrical portion defines anannular shoulder160 surrounding the juncture with thetubular portion156. The entiredissolvable locating tip150 may have an axial passage162 through its length to receive a guidewire or the like (not shown).
• The dissolvablelocating tip element150 ofFIG. 9 may be inserted into a puncture site in a blood vessel, in the manner similar to that discussed above with respect toFIGS. 6 and 7. In this embodiment, however, only thedistal tip end158 and an adjacent portion of thetubular portion156 enter the blood vessel. Thecylindrical portion152 remains outside the vessel, with theshoulder160 functioning as a compression element, much as does thefoam pad74,74′, described above in connection withFIGS. 3, 3A, and8. In this case, the compression element, being integral with and of the same dissolvable material as the locating tip, likewise dissolves in the patient's tissue after hemostasis has occurred.
• 2. Method for Sealing Vascular Punctures
• A brief review of a typical vascular entry procedure may be of value in describing the puncture closure technique of the present invention. To initiate one of the common operations such as the PTCA (Percutaneous Transluminal Coronary Angioplasty) mentioned above, a piercing cannula is inserted into the skin of a patient at an angle of from 25 to 45 degrees until it punctures a blood vessel, e.g., the femoral artery. The vessel may be located one centimeter or more beneath the surface of the skin. A guidewire is inserted through the cannula into the vessel, the cannula is withdrawn, and a catheter introducer sheath is inserted over the guidewire into the puncture site.
• The practitioner then uses the introducer to gain access to the vascular lumen for the instrumentation used to perform the particular procedure. At the conclusion of the procedure, the introducer is the last device remaining in the puncture, which must then be sealed.
• The method of the present invention provides a rapid, permanent, inexpensive sealing of a puncture in a blood vessel, with no foreign implants remaining in the patient. The method can be understood with reference to the drawing figures and the previous description of the apparatus of this invention.
• InFIG. 1A, anintroducer sheath12 is shown in apuncture site24 at the conclusion of a vascular procedure. According to one embodiment of the present invention, alocator tube30 having aninflatable locating balloon50 adjacent its distal end is inserted axially through theintroducer12, into apuncture20 and extending theuninflated locating balloon50 into the lumen of avessel18.
• Adual lumen catheter32 is passed over thelocator tube30 so that a first lumen36 (FIG. 1D) of thecatheter32 receives thelocator tube30. Thelocator tube30 maintains alignment of thecatheter32 with thepuncture20 and allows repeated access into thevessel18, if necessary. Thecatheter32, having aninflatable compression balloon42 at itsdistal end34, is inserted fully into theintroducer12 until itsdistal end34, including theuninflated compression balloon42, is at thedistal end22 of theintroducer12. At this stage, thelocator tube30 is pushed or pulled until a marker band57 (shown inFIG. 1) is aligned with theproximal end33 of thecatheter32. Themarker band57 is preselected to establish a fixed relationship with thecatheter32 so that a preferred distance may be maintained between thevessel18 and thedistal end34 ofcatheter32 as will be explained below. Theintroducer12 being in its first or distal position, theuninflated compression balloon42 is fully enclosed and contained within the workingchannel26 of theintroducer12, as described above.
• The practitioner then inflates the locatingballoon50 via thelocator tube30, partially withdrawing theintroducer12, thecatheter32 and thelocator tube30 from thepuncture20 in the direction of thearrow52, until the locatingballoon50 lodges against the inner wall of thevessel18 at thepuncture20, as illustrated inFIG. 1B. Since the position of the catheterdistal end34 relative to the introducerdistal end22 remains unchanged, thedistal end34 of the catheter is now at the location predetermined by the placement of themarker band57, preferably about 5 mm to 15 mm from thepuncture20. This distance will allow a layer of fattysubcutaneous tissue56 to lie between the catheterdistal end34 and thepuncture20.
• Once the catheterdistal end34 is in the desired location, theintroducer12 is further withdrawn in the direction of thearrow52, by moving it to its second or proximal position relative to thecatheter32, as described above, to expose theuninflated compression balloon42, as shown inFIG. 1C. Theluer fittings46,48 at the proximal ends of thecatheter32 and theintroducer12, respectively, are now connected to each other to lock thecatheter32 and theintroducer12 into a fixed position relative to one another, and thecompression balloon42 is then inflated, as illustrated inFIG. 1, via a second catheter lumen38 (FIG. 1D). Thecompression balloon42 is then pressed down against thefatty layer56 above thepuncture site24, while gentle traction is maintained on the locatingballoon50, thus compressing theextravascular fatty tissue56 between theballoons42,50. Thefatty tissue56 advantageously minimizes the potential of pseudo-aneurysm formation and promotes efficient hemostasis.
• To assist in maintaining pressure on thevessel18, anintroducer cuff60 is clamped onto theintroducer12 and secured to anadhesive patch58 means of elastic or hook and loop fastening strips64 (FIGS. 1 and 4). When theintroducer12 is locked with thecatheter32 by theluer fittings46,48, the downward force provided by the fastening strips64 is transmitted from theintroducer12 through thesemi-rigid catheter32 to thecompression balloon42, maintaining hemostatic pressure on thepuncture site24 throughfatty tissue56.
• After a first period of time (approximately 5 to 15 minutes), initial clotting of thepuncture20 will have occurred. The locatingballoon50 is then deflated and thelocator tube30 withdrawn from theapparatus10, leaving only a small (e.g., approximately 1 mm in diameter) portion of theoriginal puncture20 to clot. Thecompression balloon42 remains in place for an additional (second) period of time (approximately 5 to 25 minutes), providing hemostasis to thepuncture20, after which thecompression balloon42 is deflated and retracted proximally into theintroducer12, theluer fittings46,48 having first been disconnected. The sealing process having been completed, theapparatus10 is completely removed from the patient.
• The foregoing method uses anintroducer12 that is already positioned at the access site so that position is not lost in changing instruments, bleeding does not occur while devices are positioned, and thelocator tube30 maintains the access location for re-access if needed during the initial clotting of thepuncture20. Furthermore, employment of the present invention requires minimal physician time and greatly reduces staff time and involvement previously devoted to maintaining supradermal pressure for long periods of hemostasis. In addition, the need for operating room time may be reduced by the removal of the locator tube theintroducer12 and thecatheter32 after the patient is returned to go the patient's room. Overall, patient discomfort is significantly lessened through the use of the foregoing method as compared with the traditional manual external compression techniques.
• Similar steps are followed for implementing the method of the present invention with the second embodiment of the apparatus described above. In the second embodiment, the compression element at catheterdistal end34 comprises thecollapsible prong assembly66, as shown inFIGS. 2, 2A, and2B. In this second embodiment, once the introducerdistal end22 is in its initial (first or distal) position (about 5 to 15 mm from the vessel18) as shown inFIG. 2, the movement of theintroducer12 to its second or proximal position releases theprong assembly66 from confinement within theintroducer12, allowing theindividual prongs68 of theprong assembly66 to expand, as illustrated inFIG. 2A. A resilient spanning sheet ordam70, supported by the ends of theprongs68, then allows the application of hemostatic pressure on thefatty tissue layer56, as described earlier in connection with the compression balloon embodiment. The locator tube (not shown) passes through and is withdrawn from theaperture72 in the spanningfilm70.
• A third embodiment of the method, following steps substantially identical to the above described procedures, involves the use of thecompressible foam pad74 shown inFIGS. 3 and 3A as the compression element at thedistal end34 of thecatheter32.
• In this third embodiment, when thecatheter32 is in the preferred location as shown inFIG. 3, theintroducer12 is moved from its first or distal position to its second or proximal position (in the direction of the arrow52) to uncover thefoam pad74, allowing it to expand, as illustrated inFIG. 3A. The expandedfoam pad74 exerts hemostatic pressure upon thefatty tissue layer56, as described previously. The locator tube (not shown) passes through and is withdrawn from thepad channel76 formed axially in thefoam pad74. If deemed desirable by the practitioner, a coagulant agent such as collagen, thrombin or protamine may be delivered to the vicinity of the puncture site through thepad channel76 which communicates with the catheteraxial lumen36. Alternatively, thefoam pad74 may be saturated with the agent prior to deployment.
• The method employed with the apparatus described above may also use a guidewire78 (FIG. 4) to perform the locating functions provided by thelocator tube30 in the previous embodiments. All three of the compression elements, viz., thecompression balloon42, theexpandable prong element66 and thefoam pad74, may be utilized with theguidewire78. For purposes of illustration,FIGS. 4 through 4F, showing only thecompression balloon42 alternative, may be viewed with the understanding that the method to be described in conjunction therewith applies to all three guidewire78 embodiments.
• Referring now toFIG. 4A, theintroducer12 is shown as it remains in thepuncture20 after a vascular access procedure. A conventionalsurgical guidewire78 is extended through theintroducer12 so that itsdistal end82 extends into the lumen of thevessel18. Thedual lumen catheter32 is passed over theguidewire78 so that a first lumen36 (FIG. 1D) of thecatheter32 receives theguide wire78. Theguidewire78 maintains alignment of thecatheter32 with thepuncture20 and allows re-access into thevessel18 if it becomes necessary. As described earlier, thecatheter32, having aninflatable compression balloon42 at itsdistal end34, is inserted fully into theintroducer12 until itsdistal end34, including theuninflated compression balloon42, is enclosed within the workingchannel26 at thedistal end22 of theintroducer12, as shown inFIG. 4B.
• A radiopaque contrast medium (not shown) is introduced into the catheterfirst lumen36, as illustrated inFIG. 4. Amain leg88 of a conventional hemostasis “Y”86 may be passed over theguidewire78 and attached to theproximal end33 of thecatheter lumen36. The contrast medium is then introduced into thecatheter lumen36 via a side port90 of the “Y”86, and viewed by the practitioner using conventional fluoroscopic techniques. To aid in locating the position of the catheterdistal end34, a radiopaque marker84 may be provided at the tip of the catheter distal end34 (FIG. 4D).
• As the practitioner views the vascular scene under fluoroscopy, theintroducer12 with thecatheter32 is partially withdrawn in the direction of thearrow52 from thepuncture20. Withdrawal is continued until contrast medium in thecatheter lumen36 escaping from around theguidewire78 into thevessel18 is observed to form an extravasation cloud85, signifying that theintroducer12 and thecatheter32 have exited thepuncture20. When the practitioner is satisfied through fluoroscopy that the catheterdistal end element34 is the preferred distance of about 5 to 15 mm from thevessel18, withdrawal of thecatheter32 is halted, as shown inFIG. 4C.
• The remainder of the closure procedure is essentially the same as described above after the preferred position of thecatheter32 was determined through thelocator tube30 method. Theintroducer12 is moved from its first or distal position relative to thecatheter32 to its second or proximal position, to expose the uninflated compression balloon as shown inFIG. 4D. Thecompression balloon42 is then inflated to bear on thefatty tissue layer56 as shown inFIG. 4E. The locating means (in this embodiment guidewire78) is then withdrawn from the apparatus after an initial period of clotting (FIG. 4F). As noted previously, the method employing theguidewire78 may be effectively adapted for use with the expandable prong element and foam tip embodiments of the present invention.
• Still another method of the invention is illustrated inFIG. 5, wherein theapparatus110 differs from theapparatus10 in that theintroducer112 and thecatheter132 are not luer-locked together.FIG. 5 shows the position of thecatheter132 aligned with avisible marker band57 on thelocator tube30, just as in the first embodiment described above. It will be readily understood that the method of this “luerless”apparatus110 may be equally utilized with theguidewire78 as with thelocator tube30 for the compression balloon embodiment of this invention.
• When the preferred location of the expandedcompression balloon42 has been achieved as shown inFIG. 5, by applying either the guidewire or the locator tube methods previously explained, force must be applied from above to thecompression balloon42 to maintain hemostatic pressure on thefatty tissue layer56. The practitioner advances theintroducer112 downward in the direction of thearrow62 until the introducerdistal end22 makes contact with the surface of thecompression balloon42. This hemostatic pressure is then maintained by securing theintroducer sheath cuff60 to theskin patch58 via the fastener strips orbands64. It will be noted that no downward pressure is being exerted on thecatheter132 itself, since it has no mechanical interlock with theintroducer112, as in the previous described embodiments.
• Although certain exemplary embodiments of the invention have been described hereinabove, it will be appreciated that a number of variations and modifications may suggest themselves to those skilled in the pertinent arts. For example, a coagulant agent may be applied to any of the above-described compression elements. Such variations and modifications are considered within the spirit and scope of the invention as defined in the claims that follow.

Claims (28)

1-13. (canceled)

14. A locating device for a catheter employed to provide percutaneous sealing of a puncture in a blood vessel, the catheter having a distal end locatable adjacent the puncture, the device comprising:

a locating element on the distal end of the catheter so as to extend distally therefrom, the locating element being dimensioned to permit its entry into the puncture, the locating element being formed from a biocompatible material that dissolves in the bloodstream.

15. The locating device ofclaim 14, wherein the locating element comprises a tubular portion dimensioned to permit its entry into the puncture.

16. The locating device ofclaim 15, wherein a distal end of the tubular portion is tapered.

17. The locating device ofclaim 14, wherein the locating element has an axial passage through its length to receive a guidewire.

18. The locating device ofclaim 14, wherein the locating element comprises:

a cylindrical portion; and

a tubular portion extending distally from the cylindrical portion, thereby defining a shoulder at the juncture between the tubular portion and the cylindrical portion, the tubular portion being dimensioned to permit its entry into the puncture.

19. The locating device ofclaim 18, wherein the distal end of the tubular portion is tapered.

20. The locating device ofclaim 18, wherein the locating element has an axial passage through its length to receive a guidewire.

21. The locating device ofclaim 14, wherein the locating element dissolves in the bloodstream during a period of approximately ten to sixty minutes.

22. The locating device ofclaim 21, wherein the locating element is made of a material selected from the group consisting of methyl cellulose, carboxymethyl cellulose, carbowax, gelatin, polylactic glycolic acids, polyvinyl pyrrolidone, polyvinyl alcohol, polyproline, and polyethylene oxide.

23. The locating device ofclaim 18, wherein the locating element dissolves in the bloodstream during a period of approximately ten to sixty minutes.

24. The locating device ofclaim 23, wherein the locating element is made of a material selected from the group consisting of methyl cellulose, carboxymethyl cellulose, carbowax, gelatin, polylactic glycolic acids, polyvinyl pyrrolidone, polyvinyl alcohol, polyproline, and polyethylene oxide.

25. The locating device ofclaim 24, further comprising an expandable compression member located on the catheter proximal of the locating element for sealing the puncture in the blood vessel.

26. A device for promoting hemostasis in a blood vessel puncture where the puncture is accessed subcutaneously through a sheath having an axial channel, comprising:

a catheter to be received within the axial channel, the catheter having a distal end; and

an expansible compression means coupled to the distal end, the expansible compression means having a collapsed position when enclosed by the sheath, and an expanded position when exposed to the subcutaneous tissue,

wherein the expansible compression means compresses the subcutaneous tissue adjacent the puncture to promote hemostasis at the puncture.

27. The device ofclaim 26 wherein the catheter further comprises an axial lumen, wherein the expansible compression means is in fluid communication with the axial lumen and is inflatable by a fluid introduced through the axial lumen, the expansible compression means having a collapsed position when uninflated and an expanded position when inflated.

28. The device ofclaim 26 wherein the compression means is a foam pad having a distal end.

29. The device ofclaim 29 wherein the foam pad is made of natural a polymer.

30. The device ofclaim 29 further comprising a locating member coupled to the foam pad distal end.

31. A device for promoting hemostasis in a blood vessel puncture where the puncture is accessed subcutaneously through a sheath having an axial channel, comprising:

a catheter to be received within the axial channel, the catheter having a distal end and a lumen; and

a foam pad coupled to the distal end, the foam pad having a collapsed position when enclosed within the sheath, and an expanded position when exposed to the subcutaneous tissue;

wherein the foam pad, in the expanded position, compresses the subcutaneous tissue adjacent the puncture to promote hemostasis at the puncture.

32. The device ofclaim 31 wherein the foam pad further comprises an axial passage to receive a guidewire.

33. The device ofclaim 32 wherein the foam pad is made of a natural polymer.

34. The device ofclaim 33 further comprising a locating member extensible through the catheter lumen, the distal end of the catheter, and the foam pad axial passage, the locating member having a distal portion extensible into the interior of the blood vessel through the puncture.

35. The device ofclaim 34 wherein the locating member further comprises:

a hollow tube extensible axially through the catheter lumen, the distal end of the catheter, and the foam pad axial passage; and

a locating balloon coupled to the distal portion of the locating member, the locating balloon inflatable through the hollow tube when positioned in the interior of the blood vessel.

36. The device ofclaim 34 wherein the locating member further comprises a wire extensible axially through the catheter lumen, the catheter distal end, the foam pad axial passage, and into the interior of the blood vessel.

37. The device ofclaim 31 further comprising:

a radiopaque marker coupled to the catheter distal end; and

means for introducing a contrast medium into the catheter lumen.

38. The device ofclaim 31 further comprising a pressure applying means coupled to an external portion of the sheath.

39. The device ofclaim 38 wherein the catheter is coupled to the sheath so that the pressure applying means applies downward force to the sheath and catheter when the catheter is diposed within the axial channel.

40. The device ofclaim 38 wherein the pressure applying means comprises:

a clamping device secured to the external portion of the sheath; and

a skin patch coupled to the clamping device and adhesively attachable to the surface of the skin.

Images