Package for an active medical device

Abstract: A package 10 for an active medical device 11 comprising a film member 15 having a pocket 16 which defines a recess 13 shaped to receive the active medical device; a flange 17 about the recess 13 and a wall 18 with an opening 20 for providing access to the outside of the pocket 16; and a lid 12 covering the recess 13 to maintain a sterile field therein. Also disclosed is a method for assembling the package 10 and a method of testing the active medical device 11 while maintaining it in a sterile field within the package.

Description: This invention relates to a package for an active medical device and to a method of assembly and testing thereof. More particularly, the invention is concerned with a structure that contains the active medical device and allows testing without compromising the sterile environment provided by the package. Disposable medical devices generally are distributed in groups of like size and type which are typically carried in an over carton in a number, for example a dozen or more, of individually packaged, identical devices. A package can be removed from the over carton and opened to obtain a single disposable device. Individual packaging maintains a sterile environment for each disposable medical device. Consequently, the package for each should be inexpensive, easy to open without contamination of the product and structurally adequate to protect the sterility of the product prior to use. Commonly used packaging for disposable medical devices includes two components; a flat top or cover with printed product information such as, for example, product size, type, name of manufacturer, instructions and the like. The top or cover is usually a thin sheet of extrusion coated paper having a polyethylene layer and a heat sealable lacquer layer. The paper is called Tyvek (registered trade mark) paper and the polyethylene is added for tear resistance. The other or second component of a typical package is a drawn semi rigid pocket which has a recess for receiving the product and a flange for supporting the top or cover. The pocket preferably is thermally formed from a semi-rigid polymer sheet, for example polystyrene, which is heated and drawn such that the depth of the recess is no more than one and one-half times the width. Products which are wider than they are deep have to be packed sideways, or the package has to be drawn less than required for efficient use of the drawn polymer material. Typically, the flange is the thickest part of the formed pocket in that it is not drawn and the corners of the recess are the thinnest area because they are stretched the most. A ratio of flange thickness to corner thickness of six to one is about the maximum amount of thinning that can be accomplished with an economical starting thickness for the polymer sheet. The flange protects the device and provides support during opening. The cover and flange are heat sealed to securely enclose the product within the recess of the pocket, but a portion along an edge is usually left unsealed in order to provide an area where the top can be peeled from the flange. In particular, the unsealed portion of the edge of the top can be fanned away from the edge of the flange and then grasped and peeled away from the heat sealed areas about the rest of the flange. The product remaining within the recess is supported thereby during peeling. After removal of the top or cover, the product can be accessed without having violated the sterile field of the product, but the use of gloved hands is necessary to maintain sterility. Since the product and package are typically sterilized after assembly but before use, the package has to maintain a sterile environment until the described opening procedure is performed. A package in accordance with the preamble of claim 1 is known from EP-A-0220534. Active medical device may include optical fibres or fibre optic chemical sensors used in vivo as probes; such devices are sensitive to changes in gas or ion concentrations. U.S. Patent No. 4,200,110 discloses a fiber optic probe with an ion permeable membrane enclosure about the distal ends of a pair of optical fibres. Change in colour of a pH sensitive dye is detected. U.S. Patent Re 31,879 discloses a method for measuring concentration of an analyte in a sample that changes the colour and/or the intensity of light emitted from a fluorescent indicator attached to an optical fibre. U.S. Patent No. 5,047,208 discloses an optical sensor for blood gas measurement comprising a pH sensitive absorption dye between the end of an optical fibre and a mirror. The mirror is located by a tube which carries a mirror spaced from and coaxially aligned with the fibre so the dye is located in the space. These and other patents are typical of the prior art disclosures of microscopic constructions used for in vivo blood analysis. Blood gas sensors are typically packaged in a vessel filled with solution and then sealed in a sterility protecting package as described. The solution maintains the chemicals of the sensor fresh and ready to be used. Optical and electrical signals may be transmitted and returned through miniature wave-guides or conductors which pass through a lumen of the blood sensor catheter during use in vivo. The ability to access those miniature conductors before delivery to verify that the sensors are viable and may be used reliably is important to the manner in which active medical devices are handled in their distribution and ultimate application. In accordance with the present invention there is provided a package for an active medical device having conductors between the distal and proximal ends thereof comprising: a film member having a pocket formed therein to define a recess shaped to receive the active medical device and having a flange in a plane about the recess; a wall of the recess formed as part of the pocket, the wall having at least one flat portion generally perpendicular to the plane of the flange; and a lid covering the recess of the pocket and enclosing the active medical device, the lid being associated with the flange of the film member and thereby containing the active medical device within a sterile field in the recess; characterized in that an opening is provided in the flat portion for providing access from the recess to the outside of the pocket; and a junction is mounted in the opening through the flat portion of the wall of the pocket so as to assure the sterile field within the lidded recess, the junction including test means for the conductors of the medical device so that electrical and optical transmissions may pass through the junction without removal of the lid or breach of the sterile field. The junction preferably includes an inner part and an outer part which conjugate over the opening to seal the opening and ensure sterility within the recess. The inner part preferably has a central web therein as part of the test means so the active medical device may fit thereto in position to transmit optical signals from light conductors. The central web most preferably has thereabout a plurality of spaced apart electrically conductive pins as another part of the test means which distally couple with the test linkage proximally received. A window of transparent material in the central web permits optical signal transmission therethrough. The inner part preferably includes a band with a brim thereabout so the band fits through the opening and the brim faces the wall about the opening. The outer part preferably includes a collar with a rim thereabout so that the collar conjugates with the band of the inner part that extends through the opening and the rim abuts in tight facing relation the wall about the opening. The brim most preferably joins the band to support a gasket thereabout and the gasket is preferably of a resilient material for compression between the wall and the rim when the inner and outer parts are conjugate. In a preferred embodiment threads about the band of the inner part that extends through the opening mate with complimentary threads on the collar of the outer part so that the inner and outer parts may be drawn axially together to compress the gasket against the wall. The invention also provides a method for assembling a package for an active medical device comprising the following steps: making an opening in a wall of a recess defined by a pocket in a film member of the package, which recess is shaped to receive the active medical device; inserting a band of an inner part of a junction through the opening in the wall; placing a gasket flush against the wall and about the band; installing an outer part of the junction coaxially about the band whereat it extends beyond the opening to hold the gasket tightly against the wall to form a sterile barrier; and placing a lid against a flange of the film member to cover the recess and thereby contain the active medical device within a sterile field in the recess. The added step of threading a collar onto the band to secure the outer and inner parts may be included. The invention further provides a method of testing an active medical device in a package that provides a sterile environment comprising the following steps: placing the active medical device in a recess within the package, attaching the active medical device to a junction for transmission in and out of the package of electrical and optical signals through the junction, the junction being mounted in an opening in a flat portion of a wall of the recess; covering the recess with a lid to form a sterile field in the package; applying electrical and optical signals to the junction from outside the package, and receiving modified signals from the active medical device through the junction. The invention will be more particularly described with reference to a preferred embodiment as illustrated in the accompanying drawings, in which: Figure 1 is a perspective view of the package pocket showing the lid removed above the recess thereof and the active medical device in its packed position before use and connected for testing; Figure 2 is a partial top view of the package for the active medical device of Figure 1 as would be seen if the lid were completely removed; Figure 3 is a partial side view in cross section of the package and the active medical device of Figure 1 as would be seen if the cross section were taken along line 3-3 in Figure 1; Figure 4 is an enlarged view in cross section of the portion of the package similar to Figure 3 and showing the detail of the junction for the active medical device passage through an opening in a wall of the package; Figure 5 is an enlarged distal end view of the inner part of the junction as would be seen from inside the package; Figure 6 is an enlarged proximal end view of the inner part of the junction or the side that faces the wall of the package; Figure 7 is an enlarged proximal end view of the outer part of the junction as would be seen from outside the package; and Figure 8 is an enlarged distal end view of the outer part of the junction or the side that abuts the wall of the package. Figure 1 of the accompanying drawings illustrates a package 10 for an active medical device 11 with its conductors between the distal and proximal ends thereof, and shows a perspective view of the package 10 with a lid 12 positioned above a recess 13 thereof. As used herein the terms distal and proximal are with respect to the leading end of the active medical device 11, i.e. the part that enters the patient; this is common usage in the medical field. The active medical device 11 is depicted in its packed position before use and is attached to a junction 14 ready for testing. The lid 12 maintains a sterile field within the package 10 and about the active medical device 11. The package 10 illustrated in Figure 1 has a film member 15 having a pocket 16 formed therein to define the recess 13 shaped to receive the active medical device 11. The film member 15 preferably is a polymer sheet that has been vacuum formed with heat and pressure. The preferred material is a semi-rigid and transparent sheet of plastic less than 1 mm thick. The film member 15 includes a flange 17 in a plane about the recess 13 and a wall 18 of the recess 13 is most preferably formed as part of the pocket 16. The wall 18 includes at least one flat portion 19 generally perpendicular to the plane of the flange 17. An opening 20 is preferably D shaped with a straight edge 21 and is punched or cut into the flat portion 19 for providing access from the recess 13 to the outside of the pocket 16, as shown in Figure 3. The lid 12 covers the recess 13 of the pocket 16 and encloses the active medical device 11. The lid 12 is most preferably gas permeable for use with gas sterilization and Tyvek (registered trade mark) material is typically used. The lid 12 is associated with the flange 17 of the film member 15 and is sealed thereto by heat or solvent activated adhesive thereby containing the active medical device 11 within a sterile field in the recess 13 therein. The preferred embodiment of the present package 10 is designed to receive one side of a connector for an in vivo blood gas sensing catheter which has optical fibres and electrical conductors that terminate proximally in the connector which is adapted to be attached to monitoring instrumentation. In such an application, the proximal end of the connector is attached to the inside portion of the junction 14 in the package 10 as shown in Figures 1, 2 and 3. The junction 14 permits the transmission of optical and electrical signals even though the package 10 is sealed and the sterile field therewithin has not been breached. Specifically, the aforesaid connector has a conjugating part with terminal face features and is keyed to align the terminal face features. The terminal face features include conductors for electrical circuits and optical paths in the in vivo blood gas sensing catheter. A connection 22 occurs between the conjugating part and the junction 14 herein when the active medical device 11 of the preferred embodiment is packaged and has the features fully conjugated. The junction 14 is in the preferred embodiment mounted through the flat portion 19 of the wall 18 of the pocket 16 to maintain the sterile field within the lidded recess 13. Figure 2 is a partial top view of package 10 for the active medical device 11 of Figure 1 as would be seen if the lid 12 were completely removed. Figure 3 is a partial side view in cross section of package 10 and the active medical device 11 of Figure 1 as would be seen if the cross section were taken along line 3-3 in Figure 1. The positioning of the connector conjugating part is shown as it would appear in the preferred embodiment if the active medical device 11 were attached to the junction 14. Figure 4 is an enlarged view in cross section of the portion 19 of the package 10 and is similar to Figure 3 in showing the details of the junction 14 for the active medical device 11 where the junction 14 passes through the opening 20 in the wall 18 of the package 10, as seen in Figure 4. An inner part 23 and an outer part 24 conjugate over the opening 20 to seal the opening 20 and ensure sterility within the recess 13. The inner and outer parts 23 and 24 are moulded rigid transparent polymer and form the preferred embodiment of the junction 14. The junction 14 preferably includes test means 25 for the conductors of the active medical device 11 so that electrical and optical transmissions may pass through the junction 14 without removal of the lid 12 or breach of the sterile field. Specifically as shown in Figure 5, an enlarged distal end view of the inner part 23 of the junction as would be seen from inside the package 10, and Figure 6, an enlarged proximal end view of the inner part 23 of the junction 14 or the side that faces the wall 18 of the package 10, the inner part 23 may have a central web 26 therein as part of the test means 25 so that the active medical device 11 can fit thereto in position to transmit optical signals from light conductors. In Figure 5 a bottom slot 27 is provided on the band 28 distally to receive the key of the conjugating part and as used herein bottom is with reference to the package 10 as shown in the Figures, particularly Figure 1. In Figure 6 a section 29 of the band 28 facing proximally is removed to position the band 28 relative to the opening 20 straight edge 21. The central web 26 has thereabout a plurality of spaced apart electrically conductive pins 30 as another part of the test means 25 which distally couple with the test linkage proximally received. The preferred plurality of spaced apart electrically conductive pins 30 are conductive metal such as brass, bronze tin plated, silver plated or gold plated; specifically, part number 1364H as made and sold by Prestincert Fasteners Division of Belling Lee Limited of Middlesex, England. In the inner part 23 there are six spaced apart electronically conductive pins 30 that are parallel to one another with three above and three below the central web 26, as shown in Figures 4, 5 and 6. The spaced apart electrically conductive pins 30 are best seen in side cross section 29 in the enlarged view of Figure 4 wherein an enlarged centre bead 31 sits in a countersunk hole 32 in inner part 23 and is held therein by heat staking, glue or press fit as desired for assembly ease. A window 33 of transparent material is located in the central web 26 to permit optical signal transmission therethrough. The inner part 23 includes the band 28 with a brim 34 thereabout so that the band 28 fits through the opening 20 and the brim 34 faces the wall 18 about the opening 20 as seen in Figure 4. The outer part 24 may include a collar 35 with a rim 35a thereabout so the collar 35 conjugates with the band 28 of the inner part 23 that extends through the opening 20 and the rim 35a abuts in tight facing relation to the wall 18 about the opening 20 also in Figure 4. The brim 34 most preferably joins the band 28 to support a gasket 36 thereabout and the gasket 36 may be of a resilient material, such as soft silicone rubber, for compression between the wall 18 and the rim 35a when the inner and outer parts 23 and 24 are conjugate. Threads 37 about the band 28 of the inner part 23 that extends through the opening 20 may in the preferred embodiment mate with complimentary threads 38 on the collar 35 of the outer part 24 so that the inner and outer parts 23 and 24 may be drawn axially together to compress the gasket 36 against the wall 18, as shown in Figure 4. Adhesive or high frequency welding may be used to secure the threaded joint between the inner and outer parts 23 and 24. Figure 7 is an enlarged proximal end view of the outer part 24 of the junction 14 as would be seen from outside the package 10. There are three notches 39 shown in Figure 7, spaced about the collar 35 which may be engaged by a spanner tool to compress the gasket 36 by tightening the threads 37 and 38 between the collar 35 and band 28. Figure 8 is an enlarged distal end view of the outer part 24 of the junction 14 showing the side that abuts the wall 18 of the package 10.

Claims: A package (10) for an active medical device (11) having conductors between the distal and proximal ends thereof comprising: a film member (15) having a pocket (16) formed therein to define a recess (13) shaped to receive the active medical device (11), and having a flange (17) in a plane about the recess (13); a wall (18) of the recess (13) formed as part of the pocket (16), the wall (18) having at least one flat portion (19) generally perpendicular to the plane of the flange (17); and a lid (12) covering the recess (13) of the pocket (15) and enclosing the active medical device (11), the lid (12) being associated with the flange (17) of the film member (15) and thereby containing the active medical device (11) within a sterile field in the recess (13); characterized in that an opening (20) is provided in the flat portion (19) for providing access from the recess (13) to the outside of the pocket (16); and a junction (14) is mounted in said opening (20) through the flat portion (19) of the wall (18) of the pocket (16) so as to assure the sterile field within the lidded recess (13), the junction (14) including test means (25) for the conductors of the medical device (11) so that electrical and optical transmissions may pass through the junction (14) without the removal of the lid (12) or breach of the sterile field. A package (10) according to Claim 1, wherein the junction (14) includes an inner part (23) and an outer part (24) which conjugate over the opening (20) to seal the opening (20) and ensure sterility within the recess (13). A package (10) according to claim 1 or 2 wherein the test means (25) is on the inner part (23) and comprises a central web (26) including a window (33) of transparent material for permitting optical signal transmission therethrough so the active medical device (11) can fit thereto in position to transmit light signals from the conductors. A package (10) according to claim 3, wherein the transparent window (33) has thereabout a plurality of spaced apart electrically conductive pins (30) as another part of the test means (25) which pins distally couple with the test equipment. A package (10) according to any one of claims 2 to 4, wherein the inner part (23) includes a band (28) with a brim (34) thereabout so that the band (28) fits through the opening (20) and the brim (34) faces the wall (18) about the opening (20), and the outer part (24) includes a collar (35) with a rim thereabout so that the collar (35) conjugates with the band (28) of the inner part (23) that extends through the opening (20) and the rim abuts in tight facing relation the wall (18) about the opening (20). A package (10) according to claim 5, wherein the brim (34) joins the band (28) to support a gasket (36) thereabout, the gasket (36) being of a resilient material for compression between the wall (18) and the brim (34) when the inner and outer parts (23) and (24) are conjugate. A package (10) according to claim 6, wherein threads (37) about the band (28) of the inner part (23) that extends through the opening (20) mate with complimentary threads (38) on the collar (35) of the outer part (24) so that the inner and outer parts (23 and 24) may be drawn together along their align axis to compress the gasket (36) against the wall (18). A method for assembling a package (10) for an active medical device (11) comprising the following steps: making an opening (20) in a wall (18) of a recess (13) defined by a pocket (16), in a film member (15) of the package (10), which recess (13) is shaped to receive the active medical device; inserting a band (28) of an inner part (23) of a junction (14) through the opening (20) in the wall (18); placing a gasket (36) flush against the wall (18) and about the band (28); installing an outer part (24) of the junction (14) coaxially about the band (28) where it extends beyond the opening (20) to hold the gasket (36) tightly against the wall (18) to form a sterile barrier; and placing a lid (12) against a flange (17) of the film member (15) to cover the recess (13) and thereby contain the active medical device (11) within a sterile field in the recess (13). A method according to claim 8 which includes the added step of threading a collar (35) on to the band (28) to secure the outer and inner parts of the junction (14). A method of testing an active medical device (11) in a package (10) that provides a sterile environment comprising the following steps: placing the active medical device (11) in a recess (13) within the package (10); attaching the active medical device (11) to a junction (14) for transmission in and out of the package (10) of electrical and optical signals through the junction (14), the junction (14) being mounted in an opening (20) in a flat portion (19) of a wall (18) of the recess (13); covering the recess (13) with a lid (12) to form a sterile field in the package (10); applying electrical and optical signals to the junction (14) from outside the package (10), and receiving modified signals from the active medical device (11) through the junction (14).

Inventors: HENDRY STUART P, IRVINE MICHAEL P, MARKLE DAVID REED, HENDRY, STUART P., IRVINE, MICHAEL P., MARKLE, DAVID REED
Applicants: BIOMEDICAL SENSORS LTD
Application year: 1993
Main classification: A61B19
IPC codes: A61B19, A61B5, B65D81