Patent Application
20070000014
The present invention relates generally to protective garments for use with gloves, for example surgical gowns used with surgical gloves.
Protective garments, such as coveralls and gowns, designed to provide barrier protection to a wearer are well known in the art. Such protective garments are used in situations where isolation of a wearer from a particular environment is desirable, or it is desirable to inhibit or retard the passage of hazardous liquids and biological contaminates through the garment to the wearer.
In the medical and health-care industry, particularly with surgical procedures, a primary concern is isolation of the medical practitioner from patient fluids such as blood, saliva, perspiration, etc. Protective garments rely on the barrier properties of the fabrics used in the garments, and on the construction and design of the garment. Openings or seams in the garments may be unsatisfactory, especially if the seams or openings are located in positions where they may be subjected to stress and/or direct contact with the hazardous substances.
Gloves are commonly worn in conjunction with protective garments, particularly in the medical industry. Typically, the gloves are pulled up over the cuff and sleeve of a gown or garment. However, the interface between the glove and the protective garment can be an area of concern. For example, a common issue with surgical gloves is glove “roll-down” or slippage resulting from a low frictional interface between the interior side of the glove and the surgical gown sleeve. When the glove rolls down or slips on the sleeve, the wearer is at greater risk of exposure to patient fluids and/or other contaminants.
An additional problem associated with the use of surgical gloves is that as a result of the gloves being pulled up over the cuff and sleeve of the gown, a phenomenon known as “channeling” occurs. That is, the sleeve of the gown is bunched up under the glove as a result of pulling and rolling the glove up over the cuff and sleeve. Channels may develop along the wearer's wrist which may become accessible to patient fluids running down the outside of the sleeve of the gown. Such fluids may enter the channels and work down along the channels between the outer surface of the gown and inner surface of the surgical glove. The fluids may then contaminate the gown cuff, which lies directly against the wearer's wrist or forearm, particularly if the cuff is absorbent or fluid pervious.
Surgeons and other medical personnel have attempted to address concerns with the glove and gown interface in different ways. For example, it has been a common practice to use adhesive tape wrapped around the glove portion extending over the gown sleeve to prevent channels and roll down of the glove on the sleeve. This approach unfortunately has some drawbacks. Many of the common adhesives utilized in tapes are subject to attack by water and body fluids and the seal can be broken during a procedure. Another approach has been to stretch a rubber band around the glove and sleeve. This practice is, however, awkward to implement and difficult to adjust or to vary the pressure exerted by the rubber band other than by using rubber bands of different sizes and tensions, which of course necessitates having a variety of rubber bands available for use. Yet another approach has been to incorporate a band of elastomeric polymer on the gown around the sleeve just above the cuff to provide a surface for the glove to cling to. This approach has also proved less than completely satisfactory.
A need exists for an improved device and method for providing an effective sealing interface between a glove and sleeve of a protective garment, wherein the device is easily incorporated with the protective garment and economically cost effective to implement. A further need exists for a gown sleeve that provides a more effective barrier to fluid while retaining a glove.
The present invention provides a protective garment incorporating an effective and economical mechanism for improving the interface area between the sleeves of the garment and a glove pulled over the sleeves. The improvement inhibits the proximal end of the glove from rolling or sliding back down the garment sleeves once the wearer has pulled the gloves on. In this way, the garment according to the invention addresses at least certain of the disadvantages of conventional garments discussed above. The improvement also provides a better barrier to fluid penetration.
It should be appreciated that, although the present invention has particular usefulness as a surgical gown, the invention is not limited in scope to surgical gowns or the medical industry. The protective garment according to the present invention has wide application and can be used in any instance wherein a protective coverall, gown, robe, etc., is used with gloves. All such uses and garments are contemplated within the scope of the invention.
In an embodiment of the invention, a protective garment is provided having a garment body. The garment may be, for example, a surgical gown, a protective coverall, etc. The garment body includes sleeves, and the sleeves may have a cuff disposed at the distal end thereof. The cuffs may be formed from or include an elastic material, and may be liquid retentive or liquid impervious. The garment further includes a mechanism for improving the interface area between the sleeves of the garment and a glove pulled over the sleeves.
In one embodiment, the sleeve is formed with a film layer on the outside, where it may be contacted by a glove. The film may extend for the entire length of the sleeve or may cover a half or a quarter of the sleeve, provided it covers the area where a glove would normally contact a sleeve. This film may be of a type to enhance (increase) surface friction between the glove and garment and also increases the fluid penetration barrier properties of the sleeve. Desirably, this film may be a “low-tack” or tack-supressed film that has a relatively low level of stickiness or adhesiveness.
The “low-tack” film applied to the sleeve is desirably an inherently low-tack film with high friction characteristics so as to prevent glove roll-down while not causing the sleeves to adhere to the gown body when the gown is folded.
Embodiments of the protective garment according to the invention are described below in greater detail with reference to the appended figures.
Reference will now be made in detail to one or more examples of the invention depicted in the figures. Each example is provided by way of explanation of the invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment may be used with another embodiment to yield still a different embodiment. Other modifications and variations to the described embodiments are also contemplated within the scope and spirit of the invention.
The garment 10 is depicted as a surgical gown for illustrative purposes only. The garment 10 may be any type or style of protective covering that is generally worn about the body and includes sleeves.
The terms “lower” or “distal” are used herein to denote features that are closer to the hands of the wearer. The terms “upper” or “proximal” are used to denote features that are closer to the shoulder of the wearer.
It should be appreciated that the type of fabric or material used for garment 10 is not a limiting factor of the invention. The garment 10 may be made from a multitude of materials, including nonwoven materials suitable for disposable use. For example, gown embodiments of the garment 10 may be made of a stretchable nonwoven material so that the gown is less likely to tear during donning or wearing of the gown. A material particularly well suited for use with the present invention is a three-layer nonwoven polypropylene material known as SMS. “SMS” is an acronym for Spunbond, Meltblown, Spunbond, and includes the process by which the three layers are constructed and then laminated together. See for example U.S. Pat. No. 4,041,203 to Brock et al. One particular advantage is that the SMS material exhibits enhanced fluid barrier characteristics. It should be noted, however, that other nonwovens as well as other materials including wovens, films, foam/film laminates, and combinations thereof may be used to construct the garment of the present invention.
It is also contemplated that the garment may include a liquid impervious film to inhibit fluid absorption into the garment material. Examples of this include laminates of spunbond, film and SMS that, by nature of the inclusion of the internal film layer, are even more impervious to the passage of liquids than SMS gowns.
The sleeves 16 may incorporate a cuff 26 attached to the distal end 22 thereof. The cuff 26 also has a distal end 28 and a proximal end 30. The configuration and materials used in the cuff 26 may vary widely. For example, short, tight-fitting cuffs made from a knitted material may be provided. The cuff 26 may be formed with or without ribs. The cuff may be formed of a liquid repellant material or a liquid retentive material. Cuffs suitable for use with garments according to the present invention are described in U.S. Pat. Nos. 5,594,955 and 5,680,653, both of which are incorporated herein in their entirety for all purposes.
As shown for example in
Many types of protective gloves, particularly elastic synthetic or natural rubber surgical gloves, have a thickened bead or region at the open proximal end 36. This thickened portion or bead is intended to strengthen the glove 32 and provide an area of increased elastic tension to aid in holding the glove 32 up on the sleeve 16.
According to one embodiment of the invention, the garment 10 includes a film layer 40 formed on the outside of the sleeves 16 from the proximal end 30 of the cuff 26 (
The film 40 may extend up the sleeve 16 a distance greater than the proximal end 36 of the glove 32 extends when the glove is normally donned. The dimensions of the film area may vary as the size of the gown may also vary. As shown in
It should be appreciated that the film 40 can take on many different configurations.
The inventors have surprisingly found that a relatively uniform film of a low-tack, high-friction polymer is quite effective and lends itself easily to modern manufacturing techniques. The film 40 may be formed on the sleeve in various known ways and from a variety of materials. For example, a film compatible with the sleeve material may be applied directly to the sleeve in a co-extrusion or adhesive process or other processes known to those skilled in the art.
The film 40 may be formed of an inherently low-tack or tack-supressed material with high frictional characteristics. This type of film increases slip resistance between the glove and sleeve 16 and may be applied directly onto the exterior surface 24 of the sleeve to form the film 40. In general, the film could be any polymer that is sufficiently soft and pliable so as to cling to the inside surface of the glove 32 but at the same time should not have too high a tack level (e.g., level of stickiness or adhesiveness) so as to cause the garment sleeve 16 to stick to the garment body 12 or to itself (i.e. blocking) when the garment 10 is folded, hence the term “low-tack”. Blocking is the tendency for thin film faces to adhere to each other and it is important that the films used herein do not “block”. For example, the film 40 may be formed of a material such as a Kraton® polymer or Kraton® polymer blend that has some pressure-sensitive adhesive properties. To fit within the definition of “low-tack”, the Kraton® polymer should not have an “aggressive” initial adhesive quality that instantly creates a level of tack that would make it difficult to remove or readjust a glove or re-separate a sleeve portion that is folded over upon itself. When the film is formed from polymer blends that include tackifying agents such as, for example, tackifying resins, it is desirable to use relatively lower levels of tackifying resins or other agents such as fillers or the like to reduce or “suppress” the initial tack of the material. Importantly, the “low-tack” materials should be capable of providing slip resistance without forming a permanent bond between the sleeve portion and the glove during the time the glove is in contact with the film 40 covering the exterior portion of the sleeve during normal room temperature conditions (e.g., 20° C. and 50% relative humidity) and contact pressures. Typically, this time can range from less than an hour to several hours (e.g., 3 hours, 4 hours, 5 hours or more). It is contemplated that the contact time without permanent bonding under such conditions can be more than 10 or 12 hours.
The term “high frictional characteristics” means that one or more of the the peak load, the average load, the dynamic coefficient of friction and the static coefficient of friction of the fabric having the film is higher (i.e., greater) than the same fabric without a film when measured generally in accordance with ASTM D 1894. Desirably, all these measure are greater for the fabric having the film. In some instances, it is satisfactory for at least two of these measures to be greater for the fabric having the film. For example, the difference for a single measure (e.g., peak load, the average load, the dynamic coefficient of friction or the static coefficient of friction) may be at least from about 30 percent to about twice as great. The difference may be three (3) times as great or more. As another example, the difference may be five (5) times as great to ten (10) times as great. As yet another example, the difference may be fifteen (15) times as great. It is contemplated that ever greater differences may be satisfactory provided the “low-tack” properties of the film are maintained.
Polymers such as metallocene based polyolefins are suitable examples of acceptable film formers. Other suitable surface films include, for example, ethylene vinyl acetate copolymers, styrene-butadiene, cellulose acetate butyrate, ethyl cellulose, synthetic rubbers including, for example, Kraton® block copolymers, natural rubber, polyurethanes, polyethylenes, polyamides, flexible polyolefins, and amorphous polyalphaolefins (APAO). A number of multilayer films such as those available from Pliant Corp. of Schaumburg, Ill., are suitable for use. These include film laminates having a polypropylene core and a metallocene polypropylene or a Kraton® polymer outer layer. Suitable films also include those known as “microporous films” and particularly stretch-thinned laminate (STL) microporous films.
The film may have a thickness of between a positive amount and 2 mils, desirably between about 0.5 and 1.5 mils, more desirably between 0.7 and 1.1 mils.
Other materials may be added to the film to provide particular characteristics. These optional materials may include, for example, tackifying resins, dyes, pigment or other colorants. Colorants, for example, may be used to give the film area a visually perceptible color such as yellow, green, red or blue (e.g. Sudan Blue 670 from BASF). These colors may be used to indicate the protection level accorded by the gown according to, for example, the standards of the Association for the Advancement of Medical Instrumentation (AAMI), e.g., ANSI/AAMI PB70:2003. A user would thus be able to select a gown for a surgical procedure where the sleeve color corresponded to or indicated the fluid protection level of the gown.
Tackifying resins may be added to the extrudable films to provide tackified films. The tackifying resins and tackified extrudable compositions as disclosed in U.S. Pat. No. 4,787,699, hereby incorporated by reference, are suitable. Any tackifier resin can be used which is compatible with the polymer being used and can withstand the high processing (e.g., extrusion) temperatures. If the polymer (e.g., block copolymer) is blended with processing aids such as, for example, polyolefins or extending oils, the tackifier resin should also be compatible with those processing aids. Generally, hydrogenated hydrocarbon resins are preferred tackifying resins, because of their better temperature stability. REGALREZ® and ARKON® P series tackifiers are examples of hydrogenated hydrocarbon resins. ZONATAK® 501 lite is an example of a terpene hydrocarbon. REGALREZ® hydrocarbon resins are available from Hercules Incorporated. ARKON® P series resins are available from Arakawa Chemical (U.S.A.) Incorporated. Other tackifying resins which are compatible with the other components of the composition and can withstand the high processing temperatures, can also be used.
In order to validate the superiority of the inventive garment sleeve film in the retention of gloves, testing was carried out on a variety of films and “control” sleeves without film. The coefficient of testing (COF) was done according the ASTM testing method D1894 and the fabric was tested against the inside surface of a market leading latex glove (Biogel Surgical glove by Regent) in order to gain a more realistic picture of the sleeve's performance. The testing was done using the outside surface of each gown or example fabric, dry, with the fabric oriented in the machine direction, as it would be orientated on a wearer.
In Table 1 below, gown A (Ultra® gown from Kimberly-Clark Corporation) is a commercially available gown with sleeves made from two 1.0 osy (33.9 gsm) propylene SMS layers glued together. Gown B (MicroCool® gown from Kimberly-Clark Corporation) has a 0.6 osy (20.3 gsm) polypropylene spunbond layer over a film and polypropylene SMS fabric with the spunbond on the outside. Gown C (from Kimberly-Clark Corporation) has a 0.75 mil film on a polypropylene SMS fabric with the film on the outside. Gown D (Astound® gown from Cardinal Healthcare) has 1.6 osy (54.3 gsm) polypropylene SMS sleeves. Gown E (Proxima® gown from Medline Manufacturing) has 2.1 osy (71.1 gsm) spunlace sleeves. The next four are examples of a polypropylene (PP) core film having Kraton® G1657 SEBS polymeric or metallocene polyethylene (mPE) outerlayers. Two different thicknesses were tested, as indicated. An example of highly breathable stretch thin laminate (HBSTL) is given as well as an example similar to a gown B sleeve but without the spunbond outer layer. The film of gown B is a stretch thinned laminate and has a skin layer made of a blend of random copolymer polypropylene from Basell North America, polypropylene and calcium carbonate.
This data shows that the exemplary materials had a much higher coefficient of friction in all areas than any of the competitive, commercially available gowns. These materials had a peak load above 90, a static load above 0.5, dynamic load above 0.44, and average load above 85, more desirably the films should have a peak load above 100, static and dynamic loads above 0.6 and an average load above 100. (Note that peak and average loads are in units of grams and the static and dynamic loads are unitless.) Gowns having the film according to the invention thus have a much higher ability to retain gloves and avoid slip down and roll down.
In order to validate the superiority of the inventive garment sleeve, testing was carried out on a variety of films and a “control” sleeve without film.
The control was a sleeve made from 1.7 osy (58 gsm) SMS made from polypropylene. Three samples of sleeves of the same 1.7 osy SMS material had film added to them; sample one had a metallocene polyethylene film extending away from the cuff for 4 inches (11 cm), sample two had a metallocene polyethylene film extending away from the cuff for 6 inches (16 cm), and sample three had a Kraton® G1657 SEBS polymer film extending away from the cuff for 4 inches (11 cm). The four sleeves were tested using human subjects and an experimental protocol designed to simulate tasks performed by medical personnel in an operating room. During and after the protocol, measurements of glove location were taken for comparison. The subjects' opinions were also solicited for a qualitative indication of gown preference. A total of 47 subjects tested the gowns.
The protocol was as follows:
1. Acclimate for 10 minutes. Review Survey Questions.
2. Have the subjects wash and dry their hands using the following procedure:
Results of the testing protocol were as follows:
Average movement (slip-down) measured from the starting point was, for the control: 42 mm, for sample 1: 12 mm, for sample 2: 12 mm, and for sample 3: 9 mm. This indicates a significant advantage for the sleeves with film over the sleeve without film.
Qualitative survey responses were also gathered. The areas of inquiry were “cuff stays in place”, “acceptability of glove slip-down”, “how well to protect from fluid”, “gown acceptability”. The gown sleeves were preferred by the subjects for each category respectively in the following order: 3, 1, 2, control; 1, 3, 2, control; 1, 2, 3, control; 3, 1, 2, control. This again shows the performance and acceptability of the film sleeves was better than the sleeve without film.
It should be appreciated by those skilled in the art that various modifications and variations can be made to the embodiments of the present invention described and illustrated herein without departing from the scope and spirit of the invention. The invention includes such modifications and variations coming within the meaning and range of equivalency of the appended claims.
