Patent Publication Number: US-2022233824-A1

Title: Low profile passive protector for an i.v. catheter

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
     Not Applicable 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates generally to a universal passive protector for an IV catheter, and more specifically to a universal passive protector being specifically configured and adapted to allow for quick and easily assembly thereof. 
     2. Related Art 
     It is well known in the medical profession that various medical treatments and procedures oftentimes require the insertion or withdrawal of fluid from a patient. Intravenous needles are commonly employed to achieve such insertion or withdrawal of fluid. However, in some instances, the needle may be required to remain in the patient for an extended period of time, such as when introducing or withdrawing large amounts of fluid. Under these circumstances, metal needles are typically unfavorable due to their rigid structure and sharp distal tip which can cause trauma to the patient&#39;s vein. In view of the disadvantages associated with metal needles, medical professionals commonly use a catheter for such applications. 
     A conventional catheter typically includes a generally flexible tube having a hard/rigid distal tip. The catheter is typically inserted into a patient&#39;s vein using a catheter introduction device. Various catheter introduction devices have been developed and include through-the-needle catheters, as well as over-the-needle catheters. A through-the-needle catheter is inserted into an anatomical passage of the patient through the use of a cannula, which typically includes an elongate, metal needle which punctures the skin, tissue and vein wall to provide a path for placement of the catheter in the vein. When the needle pierces the vein, blood will “flashback” through the needle and into a flashback chamber typically located at the proximal end of the needle. Thus, the “flashback” is an indication to the medical technician that the needle has been properly inserted into the vein. At this point, the catheter is maintained stationary within the vein and the needle is withdrawn and removed from the catheter. The needle may have score lines formed therein to allow a medical technician to tear or pull the needle apart to remove the needle from the catheter once the catheter is removed from the patient. 
     Over-the-needle catheters are also commonly used by medical technicians, and typically include a thin catheter having a hub attached to its proximal end. The catheter is advanced over a rigid cannula, such as a needle, with the cannula and catheter being simultaneously advanced into a desired anatomical passage of a patient. Once the catheter has been inserted into the anatomical passage of the patient, the cannula is typically removed from the catheter by retracting the cannula through the catheter. The action of retracting the cannula can undesirably expose the medical technician as well as the patient to accidental contact with the cannula, particularly the piercing tip of the needle. Such accidental needle sticks are a serious concern in view of such diseases as Acquired Immune Deficiency Syndrome (“AIDS”), which can be transmitted through the exchange of bodily fluids with an infected person. In particular, a needle that has been used to place a catheter in the vein of an AIDS infected person may be a vehicle for transmission of the disease to the medical technician. 
     A number of protective devices have been developed recently to help reduce the incidence of disease and transmission through needle sticks. Many of the protective devices employ a protective, elongate sheath into which the needle is retracted as the needle is withdrawn from the patient. Along these lines, when the needle is withdrawn, its sharp distal tip is safely enclosed within the sheath, which is typically formed from a rigid material. 
     Operation of the protective devices generally includes an actuation mechanism connected to the needle, which is operated by the fingers of the medical technician. The technician uses various structures on the protective device to push against or pull on for retracting the needle within the sheath. However, in many protective devices, the flashback chamber is positioned in a manner which makes it difficult for the medical technician to easily grasp and manipulate the protective device in its intended manner. Such difficulty may lead to improper operation of the protective device, which may lengthen the process of inserting the catheter, or compromise the protective nature of the device. 
     Another deficiency associated with conventional protective devices pertains to the manufacture and assembly thereof. Conventional protective devices may include several components that require tedious and time-consuming assembly. As such, the cost and time associated with assembling conventional protective devices may be significant. 
     Accordingly, there is a need in the medical field for an improved protective device that is easy to assemble, and once assembled, is safe and easy to use. The present disclosure addresses this need, as will be discussed in more detail below. 
     BRIEF SUMMARY 
     According to an aspect of the disclosure, there is provided a low-profile universal passive protector for an IV catheter. The protector includes a connector having a tubular body and a pair of arms each being pivotally connected to the tubular body. The tubular body defines an end face, and the connector includes a cavity extending from the end face to the pair of arms. An elongate sheath defines a longitudinal axis, and the elongate sheath is snap engageable to the tubular body. A spring is insertable within the cavity of the connector and is configured to extend between at least one of the pair of arms and the elongate sheath when received within the cavity. A slider is moveably coupled to the sheath. The slider includes a flashback chamber formed therein. A hypodermic needle is connected to the slider and is in fluid communication with the flashback chamber. The slider is moveable along the sheath between a first position and a second position, with the hypodermic needle being drawn into the sheath as the slider moves from the first position toward the second position. 
     The slider may include a vent opening in fluid communication with the flashback chamber. The protector may additionally include a plug in the vent opening. The plug may be configured to restrict flow of liquid therethrough and to allow gas to pass therethrough. 
     The slider may include a transparent section in alignment with the flashback chamber to allow a user to view into the flashback chamber through the transparent section. The slider may be formed as a single integral body. 
     The protector may additionally include an over-the-needle catheter removeably disposed on the hypodermic needle. The over-the-needle catheter may include a hub and a tube connected to the hub, with the pair of arms being pivotable from an open position to a closed position to capture the hub within the pair of arms. 
     The connector may include a finger-press plate connected to the tubular body. The finger-press plate may extend beyond the slider in a direction perpendicular to the longitudinal axis to define a plate height when the slider is engaged with the elongate sheath and the elongate sheath is engaged with the tubular body. 
     Each of the pair of arms may include an opening formed therein. The hypodermic needle may be configured to pass through the openings of the pair of arms when the slider is in the first position. The hypodermic needle may be removed from the openings of the pair of arms when the slider is in the second position. 
     According to another embodiment, there is provided a method of assembling a low-profile universal passive protector for an IV catheter. The method includes inserting a spring into a connector having a tubular body and a pair of arms each being pivotally connected to the tubular body, with the spring being inserted into the tubular body of the connector. The method further includes positioning a sliding assembly in alignment with the connector. The sliding assembly including a slider and a hypodermic needle connected to the slider. The slider includes a flashback chamber therein, and the hypodermic needle is in fluid communication with the flashback chamber. The method also includes connecting an elongate sheath to the sliding assembling and the tubular body. The slider is slidably coupled to the sheath, and the sheath is connected to the connector via snap engagement. 
     The spring may be compressed in response to the elongate sheath being connected to connector. Compression of the spring may result in a force being imparted on the pair of arms to bias the pair of arms toward an open position. 
     The method may also include the step of connecting an over the needle catheter to the pair of arms. 
     The sliding assembly may be positioned relative to the connector such that the needle passes through both of the pair of arms. 
     The sliding assembly may be positioned relative to the connector such that the needle passes through the spring. 
     The flashback chamber may include an opening, and the step of connecting the sliding assembly to the sheath may include connecting the slider such that the opening to flashback chamber is positioned in a cavity formed in the sheath. 
     The sheath may be connected to the connector such that at least a portion of the sheath is received within the tubular body. 
     According to another embodiment, there is provided the method of assembling a low-profile universal passive protector for an IV catheter includes inserting a spring into a connector having a pair of pivoting arms. The method additionally includes positioning a sliding assembly adjacent the connector, with the sliding assembly including a slider and a hypodermic needle connected to the slider. The slider includes a flashback chamber therein, and the hypodermic needle is in fluid communication with the flashback chamber. The method further comprises connecting an elongate sheath to the connector and the sliding assembly. The elongate sheath is connected to the connector via snap engagement to compress the spring between the elongate sheath and at least one of the pair of pivoting arms. The elongate sheath is slidably connected to the sliding assembly. 
     The presently contemplated embodiments will be best understood by reference to the following detailed description when read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which: 
         FIG. 1  is an upper perspective view of a low-profile universal passive protector constructed in accordance with an embodiment of the present disclosure, the universal passive protector having a cover coupled thereto and extending over a hypodermic needle and an over-the-needle catheter; 
         FIG. 2  is an upper perspective view of the universal passive protector and cover, with the cover removed from the universal passive protector to expose the hypodermic needle and the over-the-needle catheter; 
         FIG. 3  is a rear, exploded, upper perspective view of the universal passive protector; 
         FIG. 4  is a front, exploded, upper perspective view of the universal passive protector; 
         FIG. 5  is a top, exploded view of the universal passive protector; 
         FIG. 6  is a top plan view of the universal passive protector; 
         FIG. 7  is a side view of the universal passive protector; 
         FIG. 8  is a bottom view of the universal passive protector; 
         FIG. 9  is an exploded side sectional view of the universal passive protector; 
         FIG. 10  is an assembled side sectional view of the universal passive protector; 
         FIG. 11  is an upper perspective view showing use of the universal passive protector for inserting a catheter into a patient; 
         FIG. 12  is an upper perspective view of the universal passive protector with the slider and needle in a deployed configuration; 
         FIG. 13  is an upper perspective view of the catheter detached from the sheath and inserted in a patient; and 
         FIG. 14  is an upper perspective view of the catheter detached from the sheath and the hypodermic needle retracted within the sheath. 
     
    
    
     Common reference numerals are used throughout the drawings and the detailed description to indicate the same elements. 
     DETAILED DESCRIPTION 
     The detailed description set forth below in connection with the appended drawings is intended as a description of the presently preferred embodiments of the disclosure, and is not intended to represent the only form in which the present devices may be developed or utilized. It is to be understood, however, that the same or equivalent functions may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the disclosure. It is further understood that the use of relational terms such as first, second, and the like are used solely to distinguish one from another entity without necessarily requiring or implying any actual such relationship or order between such entities. 
     Various aspects of the present disclosure are directed toward a low-profile passive protector  10  that may be specifically configured and adapted to allow for quick and easy assembly thereof. In particular, the various components of the protector  10  may be sized and configured to allow for snap-lock engagement therebetween. Furthermore, certain components of the protector  10  may be formed as a single integral unit to reduce the overall number of components, thereby reducing the number of steps that may be required to assemble the protector  10 . Accordingly, the protector  10  may be assembled quicker and in a less costly manner than conventional passive protectors  10 . 
     Referring now to  FIGS. 1 and 2 , there is shown a low-profile universal passive protector  10  for use in inserting an over-the-needle catheter  12  into a patient. The universal passive protector  10  includes a hypodermic needle  14  that is configured to be withdrawn into a sheath  16  in response to movement of a slider  18  along the sheath  16  from a deployed position to a retracted position. The universal passive protector  10  may include a detachable cover  20  that may be placed over the needle  14  and catheter  12  before using the protector  10  to protect a medical professional from an inadvertent needle stick.  FIG. 1  shows the cover  20  extending over the needle  14  and catheter  12 , while  FIG. 2  shows the cover  20  as having been removed to expose the needle  14  and catheter  12 . 
     The catheter  12  defines a proximal end portion  22 , a distal end portion  24 , and a catheter passageway extending between the proximal and distal end portions  22 ,  24 . The catheter  12  includes a hub  26  positioned adjacent the proximal end portion  22 . A catheter  12  tube, formed of a soft, flexible material, is attached to the hub  26 . The catheter  12  tube is configured to be inserted into a patient&#39;s vein, thereby providing a path for intravenous injection or aspiration of the patient. Along these lines, the hub  26  is configured to be engageable with injection/aspiration devices via a threaded luer lock. 
     The protector  10  includes a connector  28  that is configured to engage with the catheter  12  on one end and with the sheath  16  on the other end. In particular, the connector  28  includes a tubular body  30  and a pair of arms  32  each being pivotally connected to the tubular body  30 . The tubular body  30  includes an end face  34  and an inner surface  36  extending from the end face  34  to define a cavity extending into the tubular body  30  from the end face  34 . The inner surface  36  may include a first region and a second region separated by an internal shoulder, which may be used to facilitate snap engagement with the sheath  16 , as will be described in more detail below. 
     The tubular body  30  shown in the exemplary embodiment is quadrangular in configuration. In this regard, the word “tubular” as used herein refers to a structure having a wall that circumnavigates an opening, recess, or void. The word “tubular” does not refer to any specific shape or structure. Thus, the tubular body  30  may be other shapes (e.g., circular) in addition to being quadrangular. 
     The arms  32  are pivotally connected to the tubular body  30  and are moveable between a closed position and an open position. The arms  32  move closer together as they move from the open position toward the closed position, and away from each other as they move from the closed position toward the open position. According to one embodiment, each arm  32  includes a primary arm body  38  having a proximal segment coupled to the tubular body  30 , and a distal segment configured to capture the hub  26  of the catheter  12  when the arms  32  are in the closed position. The arms  32  are connected to the tubular body  30  such that the primary arm bodies  38  are arranged in generally opposed relation to each other and define a hub receiving cavity therebetween. Each arm  32  additionally includes a secondary arm body  40  coupled to the primary arm body  38  and extending into the hub receiving cavity. According to one embodiment, one secondary arm body  40  includes a slot while the other secondary arm body includes a pin or post which resides within the slot to interlock the secondary arm bodies  40  to each other. The secondary arm bodies  40  may each include a central aperture, opening, slot, etc., formed therein to accommodate passage of the needle  14  therethrough. The central apertures are co-axially aligned with each other when the arms  32  are in the closed position, to thereby allow the needle  14  to extend through each aperture. When the needle  14  is captured within the sheath  16 , and the arms  32  transition to the open position, the apertures move into a non-aligned configuration, which effectively prevents the needle  14  from leaving the sheath  16 . 
     The foregoing describes an exemplary embodiment of the arms  32 . A more detailed discussion of the arms  32  is presented in U.S. Pat. No. 6,981,965, entitled Universal Passive Protector for an IV Catheter, the content of which is expressly incorporated herein by reference. 
     The protector  10  additionally includes a spring  42  that is insertable into the tubular body cavity and is configured to bias the arms  32  toward the open position. The spring  42  may extend between the arms  32  and the sheath  16  when the sheath  16  is connected to the connector  28 . 
     The tubular body  30  may be snap engageable with the sheath  16 , which is an elongate member defining a longitudinal axis  44 . The sheath  16  includes a pair of opposed side walls  46 , a bottom wall  48 , and a sheath cavity  50  extending into the sheath  16  from between the pair of side walls  46  along the length of the sheath  16 . The sheath  16  may include a first end portion  52  configured to be snap engageable to the connector  28 . In particular, the first end portion  50  may include a first end surface  54  and a pair of inclined surfaces  56 . Each inclined surface  56  may extend from an upper surface  58  of a respective side wall  46 . The end of each inclined surface  56  adjacent the first end surface  54  may be intersect the upper surface  58  of the side wall  46 , while the opposite end of the inclined surface  56  may be spaced away from the upper surface  58  of the side wall to define a shoulder. The shoulders may be used to facilitate snap engagement with connector  28 , as will be described in more detail below. The first end portion  52  may also include an inclined surface  65  extending from the bottom wall  48  to define a lower shoulder spaced from the first end surface  54 . The lower shoulder may be additionally be used for facilitating snap engagement with the connector  28 . 
     The sheath  16  may include a second end portion  53  opposite the first end portion  52 , which is adapted to lock the slider  18  in response to the slider  18  being moved to a retracted position relative to the sheath  16 . In particular, the sheath  16  may include a pair of locking tabs  55 , each of which extends laterally outward from a respective side wall  46  of the sheath  16 . Each locking tab  55  may include an inclined surface, which intersects the side wall  46  and then extends away from the side wall  46  in a direction from the first end portion of the sheath  16  to the second end portion  53  of the sheath  16 . The sheath  16  may also include a pair of abutments  57  spaced from the locking tabs to define a stop groove  59  therebetween. A portion of the slider  18  may pass over the locking tabs and become captured in the stop groove  59  to lock the position of the slider  18  relative to the sheath  16 . 
     The exemplary embodiment of the sheath  16  defines a substantially quadrangular cross section, although those skilled in the art will appreciate that the sheath  16  may define a variety of alternative cross-sectional shapes without departing from the spirit and scope of the present disclosure. For instance, the sheath  16  may also be round (e.g., circular). 
     The sheath  16  may be formed by injection molding or via other manufacturing techniques known in the art. 
     A slider  18  is slidably connected to the sheath  16  and is rigidly connected to the needle  14 , such that movement of the slider  18  relative to the sheath  16  also results in movement of the needle  14  relative to the sheath  16 . The slider  18  may be coupled to the sheath  16  and configured in a manner such that the slider  18  extends slightly above the upper surfaces  58  of the sheath  16  to and defines a slider upper surface  60 . The slider  18  may also extend beyond the sides of the sheath  16  to define a pair of side surfaces  62 . Each side surface  62  of the slider  18  may have a slight concave configuration and a plurality of ridges to enhance the ergonomic gripability of the slider  18 . Along these lines, it is contemplated that a user will grip the slider  18  with the user&#39;s thumb and index finger being placed on respective side surfaces  62 . 
     The slider  18  additionally includes a flashback chamber  64  formed therein and in fluid communication with the needle  14  to allow blood or other bodily fluid that passes through the needle  14  to flow into the flashback chamber  64 . A portion of the slider upper surface  60  may include a transparent section  63  that is in alignment with the flashback chamber  64  to allow a user to view into the flashback chamber  64  through the transparent section. In one embodiment, the flashback chamber  64  is located in a lower portion of the slider  18  (e.g., below the upper surface  60 ) and is positioned within the sheath  16  cavity when the slider  18  is connected to the sheath  16 . The slider  18  may also include a flashback inlet  66  connectable to the needle  14  and configured to form a fluid pathway between the needle  14  and the flashback chamber  64  when the needle  14  is connected to the flashback chamber  64 . The slider  18  may further include a vent opening  68  in communication with the flashback chamber  64 . A plug  70  is insertable within a vent opening  68  to prevent blood from exiting the flashback chamber  64 . The plug  70  is preferably configured to allow gases to pass therethrough, while restricting the passage of liquids therethrough. 
     The slider  18  may also include a pair of locking tabs  74  configured to be received within a respective stop groove  59  on the sheath  16  when the slider  18  is in the retracted position. Each locking tab  74  may extend inwardly from a respective side wall of the slider  18 . 
     According to one embodiment, the slider  18  is formed as a single, integral body. The slider  18  may be molded to form the unique contours and include the features (e.g., the flashback chamber  64 , flashback inlet  66 , and vent opening  68 ) discussed above. Forming the slider  18  as a single, integral unit may simply assembly of the protector  10 . 
     The slider  18  is connectable to the sheath  16  such that the slider  18  is moveable along the length of the sheath  16  between a first, extended position and a second, retracted position. The slider  18  is rigidly connected to the needle  14  such that movement of the slider  18  from the extended position toward the retracted position causes the needle  14  to retract into the sheath  16  cavity. The slider  18  and sheath  16  may be cooperatively configured to lock the slider  18  in place when the slider  18  is moved into the retracted position so as to maintain the needle  14  within the sheath  16  for preventing inadvertent needle sticks. 
     The connector  28  may also include a finger-press plate  72 , which may extend beyond the slider  18  to define a plate height when the slider  18  is engaged with the elongate sheath  16  and the elongate sheath  16  is engaged with the tubular body  30 . The finger-press plate  72  may be specifically sized and configured to serve as a push-off point for the medical professional&#39;s index finger when transitioning the slider  18  from the extended position toward the retracted position. 
     The slider  18 , which includes the flashback chamber  64 , may be specifically sized and configured to define a low-profile relative to the finger-press plate  72  to allow the medical professional&#39;s index finger to easily interface with the finger-press plate  72 . In this regard, the slider  18  may not interfere with the medical professional&#39;s index finger when the slider  18  is positioned adjacent the finger-press plate  72  (i.e., when the slider  18  is in the extended position). The slider  18  may be configured such that the slider  18  may be of a low-profile configuration, wherein the flashback chamber  64  does not extend above a finger-press plate  72  (e.g., no portion of the slider  18  may extend above the top of the finger-press plate  72 —no portion of the slider  18  may traverse a transverse upper plane of the finger-press-plate  72 ). Thus, the flashback chamber  64  may not substantially impede the user&#39;s gripability of the protector  10  and operation thereof (e.g., movement of the slider  18  along the sheath  16 ). 
     With the basic structure of the components of the protector  10  described above, the following is a discussion of an exemplary method of assembling the protector  10 . 
     The needle  14  may be connected to the slider  18  by attaching the needle  14  to the flashback inlet  66  to define a sliding assembly. The needle  14  may include an insertion end forming a sharp tip configured to be inserted into the patient, and an attachment end configured to be attached to the slider  18 . An adhesive may be used to create a sufficient bond or interconnection between the needle  14  and the slider  18 . 
     The over-the-needle catheter  12  may be connected to the connector  28  by inserting the hub  26  of the catheter  12  between the arms  32  when the arms  32  are in the open position. The arms  32  are then squeezed toward the closed position to capture the hub  26  therebetween. Squeezing the arms  32  to the closed position also results in the openings in the arms  32  to become aligned with each other. 
     The arms  32  may remain squeezed together to maintain engagement between the catheter  12  and the connector  28 . The spring  42  may be inserted into the tubular body  30 . The insertion end of the needle  14  may be inserted through the tubular body  30 , through the spring  42 , through the aligned openings in the arms  32 , and through the over-the-needle catheter  12 . Insertion of the needle  14  causes the slider  18  to move toward the connector  28 . A front end of the slider  18  may extend over the tubular body  30  and may be disposed adjacent to or in abutment with the finger-press plate  72 . 
     The sheath  16  may be connected to the slider  18  and the connector  28 . In particular, the sheath  16  may be aligned relative to the slider  18  such that the flashback chamber  64  is positioned between the pair of side walls  46  of the sheath  16 . The sheath  16  may be inserted in the slider  18 , with the side walls  46  of the sheath  16  being received within respective channels formed in the slider  18  on opposite sides of the flashback chamber  64 . The front end of the sheath  16  is further advanced into the tubular body  30  of the connector  28  until the shoulders on the sheath  16  pass over the shoulders in the tubular body  30 , which effectuates snap engagement between the tubular body  30  and the sheath  16 . In particular, once the shoulders of the sheath  16  are in abutment with the shoulders on the tubular body  30 , the sheath  16  is restricted from being removed from the tubular body  30  in a direction opposite to insertion. 
     To insert the catheter  12  into the patient&#39;s vein using the protector  10 , a medical professional grasps the protector  10  and aligns the distal, piercing end of the needle  14  with the patient&#39;s vein. The medical professional then punctures the patient&#39;s skin with the needle  14  and guides the needle  14  into the vein. When the needle  14  has penetrated the vein, the flashback chamber  64  fills with blood. The medical professional inserts the needle  14  into the vein deep enough so that the distal end of the catheter  12  traverses a wall of the vein. 
     When the catheter  12  has been safely inserted into the vein, the technician grasps the opposed sides of the sider between the professional&#39;s thumb and middle finger, while the technician&#39;s index finger resides on top of the slider  18  and against the finger-press plate. The low-profile configuration of the flashback body reduces interference with the professional&#39;s index finger when the slider  18  is in the extended position. In this regard, the professional has greater control over the device, which minimizes shaking of the needle  14  within the patient, and allows the user to more easily push/press against the finger-press plate for moving the slider. 
     The professional then pulls the slider  18  from the extended position toward the retracted position, which in turn, causes the needle  14  to retract into the sheath  16 . When the slider  18  reaches the retracted position, the slider  18  may be locked in place on the sheath  16 . Furthermore, when the needle  14  is completely retracted into the sheath  16 , the arms  32  are no longer restrained by the needle  14 , and thus spring  42  into the open position. The catheter  12  is thus released from the arms  32  and is ready to engage with an injection or aspiration device. The needle  14  is safely stowed within the sheath  16  and the arms  32  block the needle  14  to prevent the needle  14  from exiting the sheath  16 . In this regard, the protector  10  employs a redundant locking/needle  14  capturing system including the engagement between the slider  18  and lock as well as the blockage of the needle  14  by the arms  32 . 
     Additional information regarding use of the catheter is described in U.S. Pat. No. 8,956,328, entitled Low Profile Passive Protector For An I.V. Catheter, the content of which is expressly incorporated herein by reference. 
     The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present disclosure only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects. In this regard, no attempt is made to show more details than is necessary for a fundamental understanding of the disclosure, the description taken with the drawings making apparent to those skilled in the art how the several forms of the presently disclosed disclosure may be embodied in practice.