Suction device
11013839 · 2021-05-25
Assignee
Inventors
- Bjarne Andersen (Fredrikssund, DK)
- Malin Bringsved (Gothenburg, SE)
- Sofia Frantzich (Mölnlycke, SE)
- Ulf Johannison (Landvetter, SE)
- Johan Uveborn (Askim, SE)
- Karsten Videbaek (Jyllinge, DK)
Cpc classification
B29K2075/00
PERFORMING OPERATIONS; TRANSPORTING
A61M2207/00
HUMAN NECESSITIES
International classification
A61M1/00
HUMAN NECESSITIES
B29C45/76
PERFORMING OPERATIONS; TRANSPORTING
A61M35/00
HUMAN NECESSITIES
Abstract
The present invention relates to a suction device. The suction device comprises an attachment portion adapted to be attached to a wound cover member. The suction device comprises a fluid inlet which is at least partially circumscribed by the attachment portion. The suction device also comprises a fluid outlet. The suction device further comprising a connection portion adapted to, at least during one operation condition of the suction device, provide a fluid communication between the fluid inlet and the fluid outlet. The connection portion comprises an inspection portion that is transparent to thereby facilitate the positioning of the suction device relative to the wound cover member.
Claims
1. A suction device comprising an attachment portion adapted to be attached to a wound cover member, said suction device comprising a fluid inlet being at least partially circumscribed by said attachment portion, said suction device also comprising a fluid outlet, said suction device further comprising a connection portion adapted to, at least during one operation condition of said suction device, provide a fluid communication between said fluid inlet and said fluid outlet, wherein said connection portion comprises a duct wall at least partially defining a connection duct from said inlet to said outlet, said connection portion comprising a partition wall extending at least partially from said duct wall, wherein said fluid inlet extends in a circumferential direction, said fluid inlet further extending in an axial direction being substantially perpendicular to said circumferential direction, wherein said partition wall does not extend in the circumferential direction.
2. The suction device according to claim 1, wherein said fluid outlet extends in a longitudinal direction (L), said partition wall extending in a partition wall extension (E.sub.PW) that is substantially parallel to said longitudinal direction (L).
3. The suction device according to claim 1, wherein a projection of at least a portion of said partition wall, in said axial direction and towards said inlet, is located within said inlet.
4. A kit for a negative pressure wound therapy system, said kit comprising: a suction device according to claim 1; a wound cover member adapted to be attached over a wound.
5. The kit according to claim 4, wherein said wound cover member comprises a wound cover film.
6. The kit according to claim 4, wherein said kit further comprises fluid communication means adapted to provide a fluid communication between said fluid outlet and a negative pressure source.
7. A method comprising: providing a cover member, providing the suction device according to claim 1, providing said cover member with an opening, positioning said suction device such that said fluid inlet aligns with said opening in said cover member.
8. The method according to claim 7, further comprising: applying suction to said suction device.
9. A fluid communication assembly comprising the suction device according to claim 1, i) wherein the fluid outlet comprises a first channel that is in fluid communication with a first conduit configured to provide a fluid communication with a negative pressure source; and ii) wherein the fluid outlet further comprises a second channel that is in fluid communication with a second conduit configured to provide a fluid communication to a source of air for introducing an air volume into the suction device.
10. The fluid communication assembly according to claim 9, wherein the fluid communication assembly further comprises the negative pressure source, wherein the first conduit is in fluid communication with the negative pressure source.
11. The fluid communication assembly according to claim 9, wherein the source of air is ambient air.
12. The fluid communication assembly according to claim 9, wherein the first channel and the second channel enters the connection portion on a respective side of the partition wall.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples.
(2) In the drawings:
(3)
(4)
(5)
(6)
(7)
(8)
(9) It should be noted that the appended drawings are not necessarily drawn to scale and that the dimensions of some features of the present invention may have been exaggerated for the sake of clarity.
(10) Definitions
(11) Haze measure: As used herein, the phrase “haze measure” (also known as “haze value” or “transmission haze”) refers to its ordinary meaning in the art, and describes the amount of light that is scattered as it passes through a material. As used herein, the “haze measure” is calculated as the ratio of diffuse light transmittance over total light transmittance. (See Equation 2 in Example 1 hereinbelow)
(12) Surface roughness: As used herein, the term “surface roughness” refers to its ordinary meaning in the art, and provides a measure of the texture of a surface based on vertical deviations of a surface from its ideal form.
(13) In particular the area surface roughness parameters S.sub.a (average deviation from average surface plane), S.sub.dq (average angle of surface slopes) as well as S.sub.dr (percentage of increased area compared to a plane) may be determined in accordance with the following standards: ISO 25178-2:2009 and ISO 25178-3:2009. See also Example 3 hereinbelow.
(14) Inspection portion: As used herein, the phrase “inspection portion” (also referred to as “inspection window”) refers to a portion that is characterized by optical properties that allow, for example, a user or an optical device, using light in the visible light spectrum, to see through to the other side of the inspection portion. The inspection portion may be one continuous portion. Alternatively, the inspection portion may be comprised of more than one part. In embodiments in which the inspection portion is comprised of more than one part, the more than one part(s) may be equal or unequal in surface area to each other.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
(15) The invention will, in the following, be exemplified by embodiments. It is to be understood, however, that the embodiments are included in order to explain principles of the invention and not to limit the scope of the invention defined by the appended claims.
(16)
(17) The negative pressure system illustrated in
(18) The implementation of the wound cover assembly 14 illustrated in
(19) The wound cover member 18 is generally adapted to be attached to the skin surrounding the wound. Purely by way of example, the wound cover member 18 may comprise a wound cover film. The wound cover member 18 may preferably be attached to the skin by an adhesive. Examples of adhesives that may be used include, but are not limited to, acrylic adhesives and/or silicone gel adhesives. In some embodiments, the adhesive or adhesives is/are already incorporated as part of the wound cover film. In some embodiments, the adhesive or adhesives is/are applied to the wound cover member during use. Purely by way of example, the adhesive sold under the trademark Mepiseal® by Mölnlycke Healthcare AB may be used for attaching the wound cover member to the skin surrounding the wound.
(20)
(21) The fluid communication assembly 20 may preferably comprise a suction device 22 and a conduit assembly 24 comprising one or more conduits. The implementation of the fluid communication assembly 20 illustrated in
(22) The
(23) A purpose of introducing the air volume can be, for example, to monitor and/or dissolve a blockage or obstruction that could possibly occur in the first conduit 24′. Purely by way of example, the negative pressure wound therapy system 10 may preferably comprise a dosing feeder (not shown) adapted to feed a volume of air into the volume at least partially enclosed by the wound cover member 18 upon request by an operator and/or on a regular basis. As a non-limiting example, the pressure of the air volume introduce via the second conduit 24″ may be an atmospheric pressure. Purely by way of example, the dosing feeder may comprise a valve (not shown) located in or on the negative pressure source 12.
(24) The wound cover member 18 comprises a wound cover member opening 26 allowing a fluid passage through the wound cover member 18. Purely by way of example, the wound cover member opening 26 may be pre-cut in the wound cover member 18. As another non-limiting example, the wound cover member opening 26 may be obtained after the wound cover member 18 has been arranged over the wound filler 16. For instance, the wound cover member opening 26 may be cut by a cutting tool such as a knife or a scalpel.
(25) The suction device 22 comprises a fluid inlet 28 and a fluid outlet 30. In order to obtain the desired negative pressure in the area of a wound 11, it is generally desired that the fluid inlet 28 covers the wound cover member opening 26.
(26)
(27) Moreover, the
(28)
(29) As may be gleaned from
(30)
(31) To this end, although purely by way of example, the inspection portion may have a haze measure that is equal to or less than 50%.
(32) Alternatively, the haze measure may be equal to or less than any one of the following upper limits: 45%, 40%, 35%, 30% and 25%. As another option, the haze measure may be equal to or less than 32%.
(33) Moreover, the inspection portion 38 may preferably have a total light transmittance of at least 50%, alternatively at least 60%. As another option, the total light transmittance may be at least 70%.
(34) The definition of the haze measure and the total light transmittance, as well as a test method for obtaining a measured value thereof, is presented in Example 1 hereinbelow.
(35) The above discussed properties of the inspection portion 38, i.e. the haze measure and possibly also the total light transmittance, may be obtained in a plurality of ways. Purely by way of example, the material of the inspection portion 38 may be different from the material of the attachment portion 32.
(36) As a non-limiting example, at least the inspection portion 38 may be made of polyurethane. Moreover, the inspection portion 38 may have a thickness that is within the range of 0.2 to 1.5 mm, alternatively within the range of 0.4 to 1.0 mm. As another non-limiting example, the thickness of the inspection portion 38 may be within the range of 0.7 to 0.9 mm.
(37) Furthermore, although purely by way of example, the inspection portion 38 may have a surface roughness, when using a measure that is the average angle of surface slopes S.sub.dq, that is less than or equal to S.sub.dq 20°. Alternatively, the inspection portion 38 may have a surface roughness that is less than or equal to S.sub.dq 17 °.
(38) Optionally, although purely by way of example, the inspection portion 38 may have a surface roughness, when using a surface roughness measure that is the percentage of increased area compared to a plane S.sub.dr, that is less than or equal to S.sub.dr 5%. Alternatively, the inspection portion 38 may have a surface roughness that is less than or equal to S.sub.dr 3.5%.
(39) As another non-limiting option, an implementation of the inspection portion 38 may have a surface roughness that is less than or equal to S.sub.dq 20° as well as less than or equal to S.sub.dr 5%.
(40) Moreover, it is envisaged that an implementation of the inspection portion 38 has a surface roughness, when measured as the average deviation from average surface plane S.sub.a, that is less than or equal to 1500 nm. It is further envisaged that implementations of the inspection portion have a surface roughness measure S.sub.a that is less than or equal to 1500 nm in addition to a surface roughness measure of S.sub.dq less than or equal to 20° and/or a surface roughness measure of S.sub.dr less than or equal to 5%.
(41) Examples of surface roughness data for an embodiment of a suction device 22 is presented in Example 3 hereinbelow.
(42) In the
(43) According to an implementation of the inspection portion 38, at least the outer surface 38″ has a surface roughness measure within any one of the above discussed surface measure roughness limits, viz the measure that is the average angle of surface slopes S.sub.dq and/or the measure that is the percentage of increased area compared to a plane S.sub.dr and/or the measure that is the average deviation from average surface plane S.sub.a.
(44) Moreover, the inner surface 38′ may be sufficiently smooth such that the inspection portion 38 provides appropriate transparency characteristics.
(45) According to a non-limiting implementation of the inspection portion 38, the inner surface 38′ may have a surface roughness measure that corresponds to the surface measure limits of the outer surface 38″.
(46) As another option, each one of the inner surface 38′ and the outer surface 38″ has a surface roughness measure within any one of the above discussed limits.
(47) As another non-limiting example, at least the attachment portion 32 and the connection portion 36, including the inspection portion 38, of the suction device 22 may form a unitary component. For instance, both the attachment portion 32 and the connection portion 36 may be made of polyurethane. Optionally, the entire suction device 22 is made of polyurethane. Instead of, or in addition to polyurethane, at least a portion of the suction device 22 may be made of at least one of the following materials: other types of urethanes, silicone, transparent hydrocolloid, PVC, hydrogel, copolyester, polyethylene, TPS (thermoplastic elastomers based on styrene) or TPO (thermoplastic olefins) i.e. blends of polyethylenes and polypropylenes.
(48) Purely by way of example, the suction device 22 may be flexible. This may be achieved by for instance making at least portions of the suction device 22 of one or more flexible materials, such as polyurethane, silicone, transparent hydrocolloid, soft PVC, hydrogel, copolyester, polyethylene.
(49) Although characteristics indicative of the transparency have been discussed hereinabove with reference to the inspection portion 38, it is also envisaged that embodiments of the suction device 22 may comprise one or more additional portions that is/are transparent. Purely by way of example, such portions may have one or more of the transparency indicative characteristics, such as at least one of the following: the haze measure, the total light transmittance, the material, the thickness and the surface roughness, that have been discussed hereinabove.
(50) As a non-limiting example, an embodiment of the suction device is envisaged wherein substantially the entire suction device is transparent (not shown).
(51) In a similar vein as has been discussed hereinabove, the inspection portion 38 of a suction device 22 in which the attachment portion 32 and the connection portion 36 form a unitary component may have a thickness that is within the range of 1.5 to 0.2 mm, alternatively within the range of 1.0 to 0.4 mm. As another alternative, the thickness may be within the range of 0.7 to 0.9 mm.
(52) Irrespective of whether the inspection portion 38 is of a different material than the material of the attachment portion 32 or if the inspection portion 38 and the attachment portion 32 both are portions of a unitary component, the inspection portion 38 may have a surface area of at least 10 mm.sup.2. As other examples, the inspection portion 38 has a total surface area of at least 15 mm.sup.2, at least 25 mm.sup.2, at least 50 mm.sup.2 or at least 70 mm.sup.2.
(53) Moreover, although purely by way of example, the inspection portion may have a total surface area that is equal to or less than or equal to 100 mm.sup.2, alternatively less than or equal to 80 mm.sup.2.
(54) As a non-limiting example, the portion of the suction device 22 that encloses the inspection portion 38 may be less transparent than the inspection portion 38. Purely by way of example, in an embodiment of the suction device 22, the haze measure of the portion of the suction device 22 that encloses the inspection portion 38 may be higher than the haze measure of the inspection portion 38.
(55) Moreover, the inspection portion 38 may be a continuous portion. As another alternative, the inspection portion 38 may be discontinuous, i.e. comprising two or more sub-portions. The one or more sub-portions may for example be separated from one another by one or more portions with a relatively low transparency of the connection portion 36.
(56) Purely by way of example, the inspection portion 38 may configured so as to have a magnifying effect such that at least a portion of the fluid inlet 28, when looked upon through the inspection portion 38, is magnified by the inspection portion 38.
(57) An implementation of such an inspection portion is illustrated in
(58)
(59) Moreover,
(60) As a non-limiting example, in an embodiment of the suction device 22, the thickness of the partition wall 42 may be within the range of 0.4 to 1.0 mm. As another example, the thickness may be within the range of 0.5 to 0.8 mm.
(61)
(62) The structural strength of an embodiment of a suction device 22 comprising a partition wall 42 has been tested by applying a negative pressure to the suction device. The result of the test is presented in Example 4 hereinbelow.
(63) The suction device 22 may be manufactured by injection moulding wherein a curable material is injected into a mould. Purely by way of example, the curable material may comprise polyurethane. As a non-limiting example, at least 80% of the curable material consists of polyurethane.
(64) Once the curable material has cured and the cast moulding has been removed from the mould, at least the inspection portion 38 may be post-treated such that the desired see-through characteristic of the inspection portion is obtained. Purely by way of example, the inspection portion 38 may be polished such that the surface roughness within any one of the above discussed limits may be obtained on the outer surfaces delimiting the inspection portion 38.
(65)
(66) Moreover,
(67) Purely by way of example, the mould inspection portion 50 has a surface roughness, when using a surface roughness measure that is the average angle of surface slopes S.sub.dq, of less than or equal to S.sub.dq 15°. Instead of, or in addition to above discussed surface roughness measure, the mould inspection portion 50 could have a surface roughness, when using a surface roughness measure that is the percentage of increased area compared to a plane S.sub.dr, of less than or equal to S.sub.dr 4%. As another alternative, the surface roughness of the mould inspection portion 50 may be less than or equal to S.sub.dr 3.5%.
(68) Moreover, it is envisaged that an implementation of mould inspection portion 50 may have a surface roughness, when measured as the average deviation from average surface plane S.sub.a, that is less than or equal to 1500 nm. Purely by way of example, an implementation of the mould inspection portion 50 may have a surface roughness measure of S.sub.a less than or equal to 1500 nm in addition to a surface roughness measure less than or equal to S.sub.dq 15° and/or a surface roughness measure less than or equal to S.sub.dr 4%.
(69) As a non-limiting example, an appropriate surface roughness of the mould inspection portion 50 may be achieved by polishing the mould inspection portion 50 using a diamond paste with particles the size of which are 1 micron or less.
(70) As such, by using a mould 44 such as the one illustrated in
(71) Moreover, for at least some implementations of the mould 44 that has relatively smooth mould inspection portion 50 as has been discussed hereinabove, at least 50% of the mould cavity wall that is located outside of the mould inspection portion may for instance have a surface roughness greater than S.sub.a 1500 nm. The relatively large surface roughness of a relatively large portion of the mould cavity wall implies that the cast mould, once cured, can be released from the mould 44 in a straightforward way.
(72) The mould core 49 may also have a surface roughness, at least in a mould core inspection portion 51 that corresponds to the inspection portion 38 of the suction device 22, of less than or equal to S.sub.dq 15°. Instead of, or in addition to the above discussed surface roughness measure, the mould core inspection portion 51 could have a surface roughness of less than or equal to S.sub.dr 4%. As another alternative, the surface roughness of the mould core inspection portion 51 may be less than or equal to S.sub.dr 3.5%.
(73) As another non-limiting example, a relatively large portion, e.g. more than 50%, of the area of the portion of the mould core 49 that is located outside the mould core inspection portion 51 may have a surface roughness of more than S.sub.dq 15°, alternatively of more than S.sub.dr 4%.
(74) Finally, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice.
EXAMPLE 1
(75) In order to determine the haze measure of inspection portion of a suction device, the test method proposed hereinbelow may be used.
(76) The below test method generally follows the test procedure as presented in ASTM D1003, procedure B. The test procedure is illustrated in
(77) A photomultiplier detector 56 is located inside the sphere and protected from direct light by a baffle. The geometry used is unidirectional illumination with diffuse viewing.
(78) A suction device should be tested in the condition that it is intended to assume when the suction device is to be attached to a wound cover member. As such, if the suction device is to be sterilized in a certain manner prior to being attached to the wound cover member, the suction device should consequently be sterilized in the same manner prior to being subjected to the haze measure and/or total light transmittance measurements that are presented hereinbelow.
(79) Typical methods used to sterilize a suction device may comprise ethylene oxide gas sterilization, gas plasma technology, steam sterilization, gamma irradiation, and electron beam irradiation. If there is no specific sterilization method associated with a suction device, the sterilization method as outlined in Example 2 hereinbelow could be employed.
(80) A deviation from the ASTM D1003, procedure B, standard is occasioned by the fact that the size of the inspection portion of a suction device may be smaller than the size of the entrance port 58 of the sphere. As such, a lens 60 is placed between the light source 62 (including the monochromator) and the sphere 54.
(81) The lens is a convex lens with a focal distance of 8 cm. The distance between the lens and the sample is 4 cm and the distance between the lens and the light source is approximately 1 m.
(82) The lens 60 limits the illuminated area at the entrance port 58 of the sphere to a square shaped area of approximately 4 mm.sup.2. The incident light reaches the sample surface at an angle of 8° to the normal direction of the sample surface. The angle of 8° is set by the sphere manufacturer since the sphere is also intended to be used for reflection measurements.
(83) Further, the entrance port 58 is covered with a circular aperture with a diameter of 2 mm. The focus of the lens 60 is, however, not located at the entrance port, but inside the sphere 54. This means that an undisturbed light beam, i.e., when there is no sample at the entrance port 58, will diverge after passing the focus of the lens and illuminate a circular area, due to the circular aperture at the entrance port, with a diameter of approximately 7 mm at the exit port 62.
(84) The size of the square shaped exit port 62 is 1 cm.sup.2. Light passing through the entrance aperture will fall on the exit port 62 only and not on the sphere wall 64 when no sample was placed at the entrance. A light trap at the exit port 56 will absorb all light entering the sphere 54.
(85) Spectra are obtained between 300 and 800 nm, i.e. the spectra covers the visible region between 380 and 780 nm. Total transmission spectra are acquired with a highly and diffusively reflecting Spectralon reference at the exit port 62. Diffusively scattered spectra were acquired with a light trap at the exit port 62.
(86) Integrated values of the total and diffuse transmittance τ.sub.Total and τ.sub.Diffuse, respectively, were calculated according to Eq. 1 below.
(87)
(88) wherein: S(λ) is the relative spectral power distribution of CIE Standard Illuminant D65 as given in Table 1 in ISO/CIE 10526:1999 and is representing daylight; V(λ) represents the spectral luminous efficiency of a human eye as given in Table 1 in ISO/CIE 10527:1991; τ(λ) is the transmission spectrum (total or diffuse transmission), and λ is the wavelength
(89) The total light transmittance is defined as τ.sub.Total.
(90) The haze measure is calculated according to Eq. 2 below
(91)
(92) Where τ.sub.Total and τ.sub.Diffuse are defined by and calculated according to eq. 1 above. A sample is examined twice and the haze measure is calculated as the average value of the haze measures obtained from the two examinations.
(93) A suction device according to the invention and as depicted in
(94) TABLE-US-00001 Tested area τ.sub.Total (%) Haze measure (%) Attachment portion 85 79 Inspection portion 73 32
EXAMPLE 2
Sterilization Method
(95) Sterilization in accordance with sterigenics cycle 38 may be used for the sterilization of a suction device. The cycle settings for a sterigenics cycle 38 are presented hereinbelow.
(96) TABLE-US-00002 Sterigenics Parameter Unit cycle 38 Jacket temp ° C. 38 Evacuation pressure mbar 255 Evacuation time hh:mm 01:00 Pre Humidification mbar — Pre Humidification hh:mm — Leak Rate mbar/ 15 mbar/10 min minutes Steam injection mbar — Number of steam Number — pulses Steam injection mbar — pressure increase during pulses Steam dwell hh:mm 00:15 Steam dwell pressure mbar 275 First Nitrogen injection 345 (final pressure) Eo Injection ° C. >20 temperature Eo Dwell time hh:mm 04:00 Estimated Gas mg/l 650-750 concentration Temperature during ° C. 40 Eo Dwell Chamber Pressure mbar 790 during Dwell Eo Evacuation mbar 250 Pressure Eo Evacuation Time hh:mm 00:19 N2 or Air Washes Number N2/3 N2 or Air Injection mbar 900 pressure Evacuation Pressure mbar 250
(97) Moreover, it should be noted that pre humidification is used on Sterigenics cycles, usually 12-24 hours, temperature degree of 40 Celsius and humidity >60 RH %. Additionally, aeration room is used on Sterigenics cycles, usually 96 hours, 40 degree of Celcius.
EXAMPLE 3
Surface Roughness Measurments
(98) A suction device according to the invention and as depicted in
(99) The surface roughness of the inspection portion of three individual suction device samples where determined using the following area surface roughness measures: S.sub.a (average deviation from average surface plane), S.sub.dq (average angle of surface slopes) as well as S.sub.dr (percentage of increased area compared to a plane). Moreover, the surface roughness of the attachment portion of one of the samples was measured. Each one of the above area surface roughness measures was determined in accordance with the following standards: ISO 25178-2:2009 and ISO 25178-3:2009.
(100) Each one of the suction device samples was produced by a method for producing a suction device in accordance with the present disclosure, i.e. using a mould with a relatively smooth mould inspection portion 50. The surface roughness of the mould inspection portion 50 of the mould that was used for producing the suction device samples is presented hereinbelow.
(101) Each one of the three individual samples was sterilized in accordance with the sterilization procedure outlined in Example 2 hereinabove prior to the surface roughness measurements.
(102) In order to measure the surface roughness, a Bruker NPFlex optical profiler, using 10× magnification and VSI (vertical scanning inferometry) mode was used. For each one of the three individual samples, an area of the outer surface 38″ was analysed. The measured area was 620×470 μm. Each sample is examined twice and the below surface roughness measures are calculated as the average value of the surface roughness measures obtained from the two measurements.
(103) TABLE-US-00003 Sample # S.sub.a (nm) S.sub.dq (°) S.sub.dr (%) Inspection portion 1 1320 17.1 3.7 Inspection portion 2 1213 18.9 5.0 Inspection portion 3 1485 14.4 3.1 Attachment portion 1686 20.5 5.8
(104) Moreover, the surface roughness was measured for a mould 48 with a mould inspection portion 50 as illustrated in
(105) The following surface roughness measurements were obtained for the mould inspection portion 50.
(106) TABLE-US-00004 Item S.sub.a (nm) S.sub.dq (°) S.sub.dr (%) Mould inspection portion 1432 15.0 3.4
EXAMPLE 4
Structural Strength of a Suction Device
(107) A suction device according to the invention and as depicted in
(108) The device was adhered to a flat surface by an adhesive and was connected to a negative pressure source via the device's fluid outlet. In this example, a pump was used as the negative pressure source. Negative pressure was applied at −200 mm Hg for 2 hours. No collapse or indentation of the device at the inspection portion was observed during the time in which negative pressure was applied. Thus, the integrity of the device was maintained under negative pressure.