Patent Publication Number: US-6902083-B1

Title: Method for dispensing medical items

Description:
This application is a divisional of application Ser. No. 08/879,997 filed Jun. 20, 1997, now U.S. Pat. No. 6,019,249 which claims the benefit of U.S. Provisional Application No. 60/045,137 filed Apr. 30, 1997. 

   This invention relates to devices for dispensing medical items. Specifically, this invention relates to a dispenser for dispensing varied types of medical items in a system which controls and tracks the use of medical items. 
   BACKGROUND ART 
   Medical items used in the treatment of patients often need to be tracked. Such medical items may include medications as well as medical devices and appliances. Such medical items come in various forms and sizes. For example, medications may be in the form of pills, capsules or caplets which are orally ingested. Alternatively, medications may be in liquid form. Liquid medications may be ingested, injected or applied topically to the patient. Similarly, medical devices vary from tiny machines which are implantable in the patient to larger items such as syringes, suction tubes and the like. 
   In the past the use of medical items by patients has been tracked manually. Medical providers would maintain paper records of inventories of medical items. As medical items were used for or by a patient, the use would be recorded. Paperwork was generated both for purposes of tracking the patient&#39;s treatment as well as for inventory and billing purposes. The manual tracking of medical items by patients particularly in large facilities became complex. 
   In recent years automated systems for controlling, dispensing and tracking the use of medical items have been developed. An example of such a system is shown in U.S. patent application Ser. No. 08/361,783 filed Dec. 16, 1994 and which is owned by the Assignee of the present invention. Such automated systems enable a medical technician to avoid much of the paperwork associated with tracking the use of medications, maintaining adequate inventories and billing patients. In such systems information concerning patients, medical items prescribed for the patients and medical items available for use by patients are stored in a data store. A user of the system, which is generally a health care provider such as a nurse or physician, uses a display terminal to select a patient and the medical items for the patient. In response to the user&#39;s input at the display terminal, the requested medical items are dispensed from a dispenser. The health care provider takes the item for use by the patient. 
   In the system owned by the Assignee of the present invention, the dispense of a medical item for a patient is recorded for several purposes. Information representative of the use of the item is stored in correlation with the patient&#39;s medical information for tracking the course of treatment and recovery. The use of the medical item is also recorded for billing purposes. This enables the patient&#39;s account to be charged for the value of the medical item. The use of the medical item is also recorded for purposes of tracking available inventories at various locations. This is done to assure that adequate supplies of medical items are available for dispense where they are needed. The disclosure of U.S. Ser. No. 08/361,783 is incorporated herein by reference as if fully rewritten herein. 
   The use of automated systems for dispensing medical items has resulted in a need for dispensers which can dispense medical items accurately and reliably in response to electrical signals. Such dispensers optimally should be capable of dispensing a wide range of medical items having various sizes and configurations. 
   Medical science is advancing rapidly. As science advances new and different types of medical devices and medications become available. Dispensers for medical devices must optimally be adaptable to new and different configurations of medical devices. Dispensers must be frequently refilled. Therefore it is desirable for such dispensers to be readily reloaded. Inventory of the items in dispensers must be frequently taken. There is a need for facilitating visual verification of the type and quantity of items which are in inventory in a dispenser mechanism. 
   Dispensers which are capable of dispensing various types of medical items may present difficulties because certain items are fragile and subject to breakage. It is sometimes desirable to dispense several medical items together as part of a kit. Such a system is disclosed in U.S. patent application Ser. No. 08/756,623 filed Nov. 26, 1996 which is owned by the Assignee of the present invention and the disclosure of which is incorporated herein by reference. Alternatively, health care providers may wish to dispense several different types of medical items in rapid succession, in which case several items will be delivered into a delivery location. If a fragile item is dispensed along with other items there is a possibility of breakage. Breakage is undesirable as it not only wastes a valuable medical item but may also contaminate the dispenser and may place it out of service until it can be cleaned. Thus, there is a need for medication dispensers that can dispense several types of medical items including fragile items together while minimizing the risk of breakage. 
   There is also a need to carefully monitor the use of narcotics. Steps are required by law to minimize the risk of theft of such items. It is desirable for medication dispensers to provide enhanced security which minimizes the risk that medical items may be taken from the dispenser through improper means. While enhanced security is desirable, authorized personnel who replenish medications or who service the dispenser should have ready access to the medications and dispenser mechanisms within the dispenser. 
   Thus, there exists a need for a dispenser for medical items that is capable of dispensing a wide variety of medical items, that reliably and accurately dispenses such items it in response to electrical signals, that is easy to use and which provides enhanced security for preventing unauthorized access. 
   DISCLOSURE OF INVENTION 
   It is an object of the present invention to provide a dispenser for medical items. 
   It is a further object of the present invention to provide a dispenser for medical items that reliably dispenses requested medical items in response to electrical signals. 
   It is a further object of the present invention to provide a dispenser for medical items that provides enhanced security. 
   It is a further object of the present invention to provide a dispenser for medical items that is capable of dispensing items of various types and sizes. 
   It is a further object of the present invention to provide a dispenser for medical items that includes dispenser modules that can be readily reloaded either in the dispenser or at remote locations. 
   It is a further object of the present invention to provide a dispenser for medical items that makes it easier to take inventory of the number of medical items remaining in the dispenser. 
   It is a further object of the present invention to provide a dispenser for medical items that includes interchangeable dispenser modules. 
   It is a further object of the present invention to provide a dispenser for medical items that minimizes the risk of damage to items being dispensed. 
   It is a further object of the present invention to provide a dispenser for medical items that provides two independent ways for authorized personnel to gain access to the medical items and mechanisms housed in the dispenser. 
   Further objects of the present invention will be made apparent in the following Best Modes for Carrying Out Invention and the appended claims. 
   The foregoing objects are accomplished in a preferred embodiment of the invention by a dispenser apparatus that dispenses medical items. The dispenser apparatus includes an enclosure which bounds an interior area. The enclosure includes an opening to the interior area and a movable door which is movable between positions opening and closing the opening. 
   A plurality of dispenser modules are movably mounted on the enclosure. The dispenser modules are movable between first and second positions. In the first position the dispenser modules are housed within the enclosure and in the second position the dispenser modules extend through the opening when the door is in the open position. In the preferred form of the invention the dispenser modules in the second position may be replenished with medical items or disengaged from the dispenser and taken to a remote location for replenishment. 
   In a preferred form of the invention each dispenser module includes a holder for holding medical items and a dispenser mechanism for dispensing the items in the holder in response to electrical signals. The medical items are dispensed from each dispenser module at a dispense location. The dispenser modules are each mounted on guides which enable dispenser modules to be interchangeably positioned in the enclosure. When a dispenser module is in the first position within the enclosure, the dispense location of the module is positioned adjacent to a path. The path extends in the dispenser to a delivery area from which dispensed medical items may be taken by a user. The path includes at least one energy absorbing carom surface which slows and absorbs energy from dispensed items moving towards the delivery area to minimize the risk of breakage. 
   The dispenser modules and the path are configured to provide enhanced security. The configurations of the dispenser modules and the enclosure are such that improper efforts to gain access to the medical items will cause the path to be blocked. Holders and guides which are readily movable or disengaged from the dispenser modules when in the second position, cannot be moved or disengaged when the modules are in the first position. 
   The door of the dispenser includes a secure lock mechanism. In a preferred embodiment two independent modes are provided to enable authorized personnel to move the lock to an open condition. The modes include unlocking the lock in response to electrical signals. The lock may also be opened manually in the event that an electrical failure or malfunction of the electronic control system. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1  is a front plan view of a dispenser for dispensing medical items of a preferred embodiment of the invention. 
       FIG. 2  is a schematic cross sectional view of the dispenser taken along the line  2 — 2  in FIG.  1 . 
       FIG. 3  is a view similar to  FIG. 2  with the dispenser door in the open position and a dispenser module in an extended position. 
       FIG. 4  is a view similar to  FIG. 3  showing the dispenser modules removed from the dispenser. 
       FIG. 5  is a top plan view of a first type of dispenser module configured for dispensing solid medications. 
       FIG. 6  is a partially sectioned front view of the dispenser module shown in FIG.  5 . 
       FIG. 7  is a side view of the dispenser module shown in FIG.  5 . 
       FIG. 8  is a top plan view of a reference surface of the dispenser module shown in  FIG. 5  with indicia thereon for indicating the number of medical items remaining in each holder of the dispenser module. 
       FIG. 9  is a side view of a guide used in connection with a dispenser module shown in FIG.  5 . 
       FIG. 10  is a top view of the outer end of the guide shown in FIG.  9 . 
       FIG. 11  is a cross sectional view of the guide taken along line  11 — 11  in FIG.  9 . 
       FIG. 12  is a top plan view of a dispenser module similar to that shown in  FIG. 5  configured for dispensing larger medical items. 
       FIG. 13  is a transparent partial plan view of the dispenser shown in FIG.  1  and the path taken by dispensed medical items. 
       FIG. 14  is a top plan view of a second type of dispenser module used for dispensing medical items which include liquid medications. 
       FIG. 15  is a side cross sectional view of the front portion of the dispenser module shown in  FIG. 14  with the medications not shown. 
       FIG. 16  is a top plan view of the dispenser shown in  FIG. 14  with the medications and dividers removed. 
       FIG. 17  is a front plan view of a first follower used in connection with the dispenser module shown in  FIGS. 14-16 . 
       FIG. 18  is a front plan view of a second follower used in connection with the dispenser module shown in  FIGS. 14-16 . 
       FIG. 19  is a side view of a guide used in connection with the dispenser shown in  FIGS. 14-16 . 
       FIG. 20  is a partial side view of the lock used in connection with the door of the dispenser mechanism. 
       FIG. 21  is a top view of the lock shown in FIG.  20 . 
       FIG. 22  is a front transparent view of the lock shown in FIG.  20  and the door of the enclosure. 
       FIG. 23  is an enlarged view of the lock shown in FIG.  22 . 
       FIG. 24  is a top plan view of a portion of a dispenser module of the type shown in  FIG. 5  configured to dispense medical items which are in the form of small cylindrical containers. 
       FIG. 25  is a top plan view of a portion of a dispenser module similar to that shown in  FIG. 5  configured to dispense cylindrical containers of a larger size than those in FIG.  24 . 
       FIG. 26  is a top plan view of a portion of a dispenser module similar to that shown in  FIG. 5  configured to dispense ampules and cylindrical containers. 
       FIG. 27  is a front isometric view of a helix guide of the type shown in FIG.  26 . 
       FIG. 28  is a front isometric view of a medication limiter of the type shown in FIGS.  24 - 26 . 
   

   BEST MODES FOR CARRYING OUT INVENTION 
   Referring now to the drawings and particularly to  FIG. 1 , there is shown therein a dispenser apparatus for dispensing medical items of a preferred embodiment of the present invention generally indicated  10 . The dispenser is used as part of the system which is described in co-pending application Ser. No. 08/361,783 filed Dec. 16, 1994, the disclosure of which is incorporated herein by reference. Dispenser  10  includes an enclosure  12 . The enclosure bounds an interior area generally indicated  14  as shown in FIG.  2 . 
   Enclosure  12  has a door  16  movably mounted thereon. Door  16  is movable between a closed position shown in  FIGS. 1 and 2  and an open position which is shown in FIG.  3 . In the open position the door enables access through an opening generally indicated  18 , to the interior area  14 . 
   Dispenser  10  further includes a delivery area generally indicated  20 . Medical items dispensed from dispenser  10  are accessible to a user in the delivery area as later described in detail. 
   As shown in  FIG. 2 , enclosure  12  further includes a lock  22  thereon. Lock  22  which is later described in detail is operative to hold door  16  in a closed position. Lock  22  includes two independently actuatable unlocking mechanisms which enable changing the lock from a locked to an unlocked condition so door  16  may be opened. 
   As shown in  FIGS. 2 and 3 , enclosure  12  has mounted thereon a plurality of dispenser modules  24 . Dispenser modules  24  are movably mounted on guides  26  in enclosure  12 . Guides  26  preferably comprise transversely disposed pairs of guides which enable dispenser modules  24  to move in sliding engagement thereon. Each of the dispenser modules further includes thereon a pair of disposed guide tracks which engage the guides  26  in slidable relation. Guides  26  may be conventional types which operate in a manner hereinafter described. It should be understood that although in  FIGS. 2 and 3  only five spaces are shown for dispenser modules  24 , in other embodiments of the invention additional guides and dispenser modules may be used. 
   Shown positioned within enclosure  12  in  FIG. 2  is a first type of dispenser module  28  and a second type of dispenser module  30 . Dispenser module  28  which is described in detail later, is preferably configured for dispensing medical items such as medications of the pill or caplet type. Dispenser  30  is of a type that dispenses medical items that are housed in cylindrical containers, including containers which hold liquid medications. The dispenser mechanism in dispenser module  30  is preferably the type shown in U.S. patent application Ser. No. 08/361,783 filed Dec. 16, 1994 which is incorporated herein by reference. It should be understood that dispenser modules  28  and  30  are exemplary, and that other types of medication dispensing modules may be used in other embodiments. The dispenser modules are preferably interchangeable on guides  26 . In  FIGS. 2 and 3 , only two dispenser modules  24  are shown for purposes of simplicity. Dispenser modules may be mounted on each pair of guides  26 . 
   The dispenser modules  24  are controlled by electrical signals which are delivered through a plurality of wiring harnesses generally indicated  32 . Wiring harnesses  32  extend in the interior area  14  of enclosure  12 . Each wiring harnesses  32  terminates in a connector end  34 . Connector ends  34  are engageable with coupling ends on the dispenser modules and provide a quick connect/disconnect electrical coupling for connecting each wiring harness to a dispenser module. 
   Dispenser modules  28  and  30  each include a pair of spring-loaded latching levers adjacent to the front ends thereof. Latching levers  36  extend on dispenser module  28 . Similarly, a latching lever  38  extends on dispenser module  30 . The latching levers  36  and  38  are movably mounted about pivots  40  and  42 , respectively. The latching levers are biased downwardly by springs to engage latching pins  44  which extend adjacent to each of guides  26 . The engagement of the latching levers with the latching pins holds the dispenser modules in position to dispense medical items within enclosure  12 . Latching levers  36  each include a release portion  46 . Release portion  46  is manually movable to cause latching lever  36  to disengage from a latching pin  44 . Latching lever  36  and release portion  46  are shown in greater detail in FIG.  7 . Latching levers  38  also include release portions  48  which are operative to move the latching lever  38  to disengage from a latching pin. When the dispenser modules are disengaged from the latching pins the dispenser modules may be moved outwardly through opening  18  on guides  26 . 
   Dispenser module  28  includes a dispense location generally indicated  50 , which is adjacent to a front end thereof. Dispense location  50  is where medical items are dispensed from the dispenser module  28 . Dispenser module  30  also includes a dispense location generally indicated  52 . Dispense location  52  is similarly located adjacent to a front end of dispenser module  30 . When the dispenser modules are positioned in the dispenser, dispense locations  50  and  52  extend adjacent to a path generally indicated  54 . Path  54  extends from the dispense locations on the dispenser modules to the delivery area  20 . Delivery area  20  includes a pocket generally indicated  56 . 
   Path  54  is bounded in an area adjacent to the dispenser modules by an interior surface  58  of door  16 . In the operative position of the dispenser modules the dispense locations thereof are disposed not only upwardly, but also in closer proximity to the interior surface of the door with increasing proximity to the top of the dispenser. This minimizes the risk that medical items dispensed from a dispenser module located vertically above other dispenser modules will engage or otherwise interfere with the lower dispenser modules or items being dispensed therefrom. 
   The preferred embodiment of the invention is enabled to be used with various types and sizes of medical items. When several medical items are being dispensed together as part of a kit, such as disclosed in U.S. patent application Ser. No. 08/756,623 filed Nov. 26, 1996 the disclosure of which is incorporated herein by reference, several items may be dispensed from the dispense locations into path  54  simultaneously. Such medical items will all move downward in path  54  and collect in pocket  56  of the delivery area. Several medical items may also collect in pocket  56  when medical items are dispensed in rapid succession. Because certain medical items may be fragile or subject to breakage, there is a risk that medical items may impact one another and break or otherwise be damaged. 
   The risk of damage to dispensed medical items is minimized in a preferred embodiment of the present invention by an angled carom surface  60  at a lower end of path  54 . Carom surface  60  is positioned in a throat area generally indicated  62 , wherein path  54  narrows horizontally (see FIG.  13 ). Carom surface  60  is covered with material which absorbs energy from medical items landing thereon. Carom surface  60  is angled and has a low surface friction value to assure that medical items which land thereon will not stick or be hung up on the carom surface. This feature is particularly useful for lightweight items. 
   Items which have engaged the carom surface fall downwardly through an elbow area  64  in path  54  and are directed into pocket  56 . To minimize possible damage due to forward momentum from engagement with carom surface  60  and the surface bounding elbow area  64 , pocket  56  includes a stop surface  66  which is coated with energy absorbing material. The interior surface of door  16  includes a guide  58  attached thereto. Guide  58  is preferably comprised of plastic material and directs medical items in the path  54  to engage carom surface  60 . The guide  58  provides smoother and quieter dispensing operation and minimizes the risk of damage to dispensed medical items. 
   As can be appreciated from  FIG. 13 , medical items such as ampules  68 , vials  70  and cards  72  with pills or capsules attached thereto are directed by the guide  58  on the inside of door  16  to fall downwardly into engagement with carom surface  60 . Upon engagement with carom surface  60 , much of the downward momentum gained by the medical items while falling through the upper portions of path  54  is lost to the energy absorbing material on the carom surface. Thereafter the medical items slide off the carom surface and slide on the generally low friction plastic surface bounding elbow area  64  until they reach the pocket  56  in delivery area  20 . Relatively heavy medical items such as ampules  68  and vials  70  may gain further forward momentum as they pass through the elbow area. The risk of damage due to collisions with such items is minimized by the energy absorbent stop surface  66 . Medical items which land near the sides of the carom surface engage the curved side walls of the elbow area which further reduces forward momentum. The dispensed medical items collect in pocket  56  until removed by a user. 
   The configuration of path  54  provides enhanced security against improper access to the medical items in the dispenser modules  24 . The opening to delivery area  20  is relatively small to restrict access into the interior area of the dispenser. Elbow area  64  is turned and throat area  62  is sufficiently small that a person attempting to pass a hand or tool upwardly therein to reach the dispenser modules would find it difficult to do so. Attempts by such a person to dislodge medications held in the dispenser modules are not likely to disengage the latching levers from latching pins  44  because there are two latches holding each dispenser module in position. However, if a dispenser module is unlatched the dispenser module will move forwardly on guides  26  due to the force of gravity. An unlatched dispenser module will move in a forward direction until it engages the guide  58  which comprises an interior face of the door. A dispenser module in this position blocks the path  54 . This prevents an unauthorized person from gaining access through the path to the medical items housed on the dislodged dispenser module or on dispenser modules located above the dislodged dispenser module. The unlatched dispenser module renders the dispenser module at least partially inoperative and its improper position is apparent to a person opening the door to the dispenser. This provides an indication of tampering. Each of the dispenser modules  28  and  30  includes further features for preventing the unauthorized access to medications therein which are hereinafter described. 
   A fundamental aspect of the preferred embodiment of the present invention is that the dispenser modules  24  are selectively movable for purposes of loading the dispenser modules with medical items or inventorying items housed thereon. As shown in  FIG. 3 , with lock  22  in an unlocked condition door  16  may be moved to an open position. In the open position of door  16  the dispenser modules  24  may be moved outwardly on guides  26 . The dispenser modules may be moved outwardly through the opening  18  after unlatching the latching levers from the latching pins  44  in the enclosure. 
   In  FIG. 3 , dispenser module  28  is shown in the outward position. In the outward position the medical items in the holders on the dispenser modules may be inventoried or replenished in a manner hereinafter discussed. After the activities related to dispenser module  28  have been completed, it may be moved back inward into the enclosure until the latching levers  36  again engage pins  44  and another dispenser module, such as dispenser module  30 , may be moved outward through the opening. 
   The guides  26  on which the dispenser modules  24  are mounted preferably include stops. The stops limit the outward travel of the dispenser modules through the opening to a distance sufficient for purposes of replenishment or inventorying the medical items thereon. The guides normally hold the dispenser modules through the guide tracks, and limit movement of the modules to sliding motion along the direction of the guides. However as shown in  FIG. 4 , in a preferred embodiment of the invention the guides  26  enable the dispenser modules to be completely released from the enclosure using conventional release mechanisms in connection with guides  26  and the guide tracks. The quick disconnect capability of the connector ends  34  on to wiring harnesses  32  enable the dispenser modules  24  to be electrically disconnected from the dispenser  10 . This enables the dispenser modules to be taken to a remote location for replenishment, inventory purposes, a modification in configuration or for repair. The same or substitute dispenser modules may be reinstalled in connection with the guides and placed back in service in the dispenser  10 . 
   One embodiment of dispenser module  28  is now described with reference to  FIGS. 5 through 11 . Dispenser module  28  includes a plurality of holders thereon for holding a plurality of different types of medical items. Each holder includes a spiral member or helix  74 . Each helix is selectively rotatable by a dispenser mechanism which includes a rotating mechanism generally indicated  76 . Each rotating mechanism preferably includes an electric motor  82  (only a portion of which is shown) and a spool  78 . Spool  78  includes tabs thereon for releasibly holding the helix  74 . Each helix also has a free end  80  which is positioned adjacent to the dispense location indicated  50  which is at the front of the module  28 . 
   As shown in  FIG. 6 , each spool  78  has in connection therewith a cam  83  and a cam operated switch  84 . The cam and cam switch enable monitoring the rotational position of the helix  74 . This enables the electric motors which are part of the rotating mechanisms  76  to accurately make one rotation in response to electrical signals delivered thereto. As will be appreciated by those skilled in the art, the rotation of each helix  74  one turn causes a medical item held thereon to be moved towards dispense location  50  adjacent the free end  80  of the helix. A medical item is preferably positioned in nested relation in each turn of the helix  74 . As a result, with each rotation of the helix by the rotating mechanism one medical item is moved outwardly to disengage the free end  80  of the helix and to fall into path  54  when the dispenser module is mounted in the dispenser. 
   It should be appreciated that although all six of the helixes  74  shown in dispenser  28  in  FIG. 5  are of the same size and pitch, various sized helixes may be used. Different sized and pitched helixes may be used for dispensing different sized medical items. For example, a larger helix suitable for handling larger sized medical items will have fewer turns for a given length. As a result, such a helix will hold fewer medical items within the given length. A smaller helix will be suitable for handling smaller medical items and will have more turns and thus hold a larger number of medical items within the given length. As later discussed, this feature is used to advantage in a preferred form of the present invention by providing indicia on the dispenser module indicative of the number of medical items remaining in a helix. 
   A novel aspect of the preferred embodiment of the present invention is that each helix is secured in position by a u-shaped holder guide  86 . Each holder guide includes a first portion  88  which extends in a longitudinal direction in an interior area of the helix  74 . Each holder guide further includes a second portion  90 . Second portion  90  extends in the longitudinal direction in an exterior area of the helix  74 . In the preferred form of the invention second portion  90  includes an engaging end  92  which is movably positionable in an opening in a wall that extends adjacent to helix  74 . 
   As shown in  FIG. 5 , a guide wall  94  extends adjacent to each helix  74  and is fixably attached to dispenser module  28 . Guide wall  94  in the embodiment shown serves to help guide and position the medical items held on helix  74  as they are moved forward thereon. As best shown in  FIG. 6 , holder guide  86  includes a closed end portion  96 . Closed end portion  96  is generally u-shaped and connects the first and second portions of the holder guide. Free end  80  of helix  74  passes through the holder guide as the helix rotates. 
   Guide wall  94  includes a pair of notches  98  at its forward end. Closed end portion  96  in the operative position extends through one of notches  98 . Guide wall  94  also includes a tab  100  adjacent to its outward end. Tab  100  includes a pair of apertures  102 . Holder guide  86  also extends through one of the apertures  102 . This further helps to position the holder guide in a proper location as well as to constrain its movement. 
   Unauthorized persons attempting to obtain the medical items housed within the dispenser  10  may seek to dislodge the medical items held on the helixes  74 . The holder guides  86  are operative to minimize the chance that this may occur. The first portion  88  of the holder guides which extends in the interior area of the helix prevents the helix from being disengaged from the holder guide  86 . In addition, the closed end portion  96  prevents significant movement of the helix outwardly so that few if any medical items can be dislodged by using a tool that attempts to pull outwardly on the helix. A further aspect of the holder guides is that the engagement of the closed end portion  96  in one of notches  98  and apertures  102  makes it difficult to engage the holder guide when it is in position within the enclosure. 
   If by chance the engaging end  92  is disengaged from the opening to which it is releasibly attached by a person attempting to compromise the dispenser, the holder guide is constrained to move forwardly by the aperture  102 . Any such attempted forward movement of the holder guide is limited by engagement of the holder guide with the interior surface  58  of the door  16  when the door is in the closed position. As a result, in the unlikely event that an unauthorized person is successful in dislodging the holder guide, the distance that the helix may be moved is very limited and the number of medical items that could be obtained in this manner is limited. 
   Authorized personnel who open the door  16  of the enclosure are enabled to readily remove the holder guide. This is accomplished because in the open position of the door the holder guide is enabled to be moved forwardly through the aperture  102  an unlimited amount. This is done when reconfiguring the dispenser module  28  by installing a different sized helix. It should be noted that the purpose of the multiple notches  98  and apertures  102  on guide wall  94  is to enable the holder guide  86  to be selectively positioned so as to extend in the proper location in the interior area of the helix. In addition, multiple openings are provided for engaging end  92  so it may be positioned in alignment with the notches and apertures in which the holder guide is positioned. This enables an authorized person to rapidly change the size and type helixes used in the dispenser module  28 . 
   Dispenser module  28  further includes a plurality of guides  104 . Each guide  104  which is shown in greater detail in  FIGS. 9-11 , is selectively positionable in disposed parallel relation with each guide wall  94 . Each guide  104  is operative to help guide medical items supported on the adjacent helix  74  outwardly towards the free end of the helix. 
   Dispenser module  28  includes a supporting surface generally indicated  106  which in the embodiment of the invention shown, extends across the bottom of the dispenser module  28 . Supporting surface  106  includes a plurality of first slots  108  which are uniformly spaced thereon. Supporting surface  106  further includes second slots  110  disposed rearwardly and in alignment with each of first slots  108 . 
   Dispenser module  28  further includes support brackets  112 . Support brackets  112  include a vertically extending wall portion which extends adjacent to spool  78 . Support bracket  112  further includes a generally horizontally extending wall portion which includes third slots  114  therein. Third slots  114  extend in aligned relation with second slots  110 . In addition, third slots  114  extend downwardly a portion of the length of the vertically extending wall portion. 
   Guide  104  includes a hook portion  116  adjacent a first end. Guide  104  further includes a rear tab  118  and a finger portion  120 . The downward and rearward configuration of tab portion  116  is operative to minimize the risk that guide  104  when engaged on dispenser module  28 , can be disengaged by unauthorized persons attempting to gain access to the medical items in the dispenser. This is because the hook portion  116  when engaged in a first slot  108 , cannot be readily moved out of engagement with the slot unless the guide is moved substantially upwardly adjacent to the rear tab  118  and finger portion  120 . In the operative position of the dispenser module within enclosure  12  such upward movement is prevented either by an adjacent dispenser module, or in the case of an uppermost dispenser module by an interior wall bounding the enclosure. 
   As will be appreciated from  FIGS. 5 and 6 , guides  104  are selectively engaged with slots  108 ,  110  and  114  so that guide  104  extends a desired distance transversely disposed from corresponding guide wall  94 . The distance that guide  104  is disposed from the guide wall depends on the physical size of the medical item held on the adjacent helix  74 . 
   The installation of guide  104  requires that portion  116  be first engaged in one of first slots  108 . Because of the configuration of hook portion  116  the engagement of the hook portion requires that the end of guide  104  including the finger portion be substantially raised relative to the supporting surface  106 . Once the hook portion is engaged with a first slot  108 , the opposed end of guide  104  is moved downwardly. As this is done rear tab  118  engages an aligned second slot  110 . Finger portion  120  extends in an aligned third slot  114  and it is engaged to the vertically extending wall portion. This engagement at three points holds the guide  104  in position. 
   Conversely, the removal of the guide requires first raising the end of the guide containing rear tab  118  and finger  120 . Only after the end of guide  104  opposed from hook portion  116  has been sufficiently raised can the hook portion be disengaged from first slot  108 . This is readily accomplished when the dispenser module  28  is in the position shown in FIG.  3 . However when the dispenser module is in the operative position within the enclosure as shown in  FIG. 2 , any upward movement of the guide  104  at the end adjacent to finger  120  is restricted by the adjacent dispenser modules and/or the interior wall of the enclosure. As a result, any person attempting to gain unauthorized access to the medical items within the dispenser using a tool in the path  54 , will find it difficult to achieve access to the medical items by dislodging guides  104 . 
   As shown in  FIG. 10 , guides  104  include a tapered front portion  105 . Tapered portion  105  is positioned above hook portion  116  when the guide is in the operative position. As shown in  FIG. 11 , guide  104  includes elongated protuberances  107 . The protuberances  107  serve to support medical items and minimize frictional resistance to movement. A tab portion  109  of the guide  104  also includes protuberances thereon which facilitate manually engaging the guide during installation and removal. 
   A further fundamental advantage of the preferred form of dispenser module  28 , is that supporting surface  106  serves as a reference surface with indicia thereon which helps a user to readily determine the number of medical items being held in a helix.  FIG. 8  shows indicia generally indicated  122  which extend on supporting surface  106 . Indicia  122  are spaced in aligned, side by side relation and correspond with the pitch of the turns in one of three different sized helixes. As can be appreciated from  FIG. 8 , the helixes which are attached to spool  78  extend adjacent to and above indicia  122 . The turns of the helix are positioned such that a user reviewing the indicia from above is able to observe the numbers corresponding to the helix through the turns of the helix. This makes it apparent which of the three sizes of helixes is installed. The indicia  122  are positioned so that the first number which is exposed is indicative of the number of medical items which are being held in the helix. This enables the user to quickly observe how many medical items are remaining on the helix for inventory purposes. 
   The use of the indicia in the preferred embodiment avoids the need for a user to have to count medical items held in a helix. This greatly reduces the time necessary for purposes of taking inventory. Further, the indicia presents the advantage that nothing must be changed when a helix which serves as a holder for the medical items is replaced with a different sized helix, which may need to be done for purposes of reconfiguring the system. In a preferred embodiment of the invention the indicia corresponding to different sized helixes may be presented in contrasting colors to make more apparent the number of items remaining to be dispensed. 
   As previously discussed, the preferred embodiment of dispenser module  28  may be configured in numerous ways to accommodate different sizes and types of medical items. An alternatively configured dispenser module generally indicated  128  is shown in FIG.  12 . Dispenser module  128  is identical to dispenser module  28  except in the specific details noted. Dispenser module  128  includes a holder generally indicated  124  for relatively large sized medical items. Holder  124  includes a first helix  126  disposed to the right as shown in  FIG. 10 and a  second helix  130  disposed to the left as shown in FIG.  12 . Helix  126  is turned by a dispenser mechanism which includes a spool  132  supported on a first support bracket  134 . Helix  130  is turned by a spool  136  of the dispenser mechanism which is supported on a support bracket  138 . It should be noted that support brackets  134  and  138  are mirror images of one another. 
   Spools  132  and  136  are each driven by a rotating mechanism in increments of one turn in a manner previously discussed. However the rotating mechanisms are configured to rotate in opposite directions. Medical items which extend across holder  124  and engage each of helixes  126  and  130  are moved uniformly in an outward direction until they disengage the free ends of the helixes and fall into path  54  of the dispenser. 
   Dispenser module  128  is configured to hold larger sized medical items than those which are held in the three other holders and associated helixes thereon. For example, holder  124  may be used to hold and dispense cards with a plurality of capsules and pills. Alternatively, holder  124  may be used to dispense medical items such as syringes or medical appliances. 
   It is a fundamental advantage of the preferred embodiment of the present invention that the dispenser modules may be configured for holding and dispensing medical items of various sizes, including those items which extend a substantial width. The only limiting factor for purposes of dispensing items is the width of items that are enabled to pass through the throat area  62  of the path  54  and into the pocket  56 . Of course, in modified versions of the invention which are specifically adapted for dispensing large items the dispenser module of the type shown in  FIG. 12  can be used for dispensing very large items such as catheters and suction tubes which extend the full width of the dispenser module. 
   Alternative configurations for portions of dispenser modules are shown in  FIGS. 24-26 . It should be understood that these are alternative configurations for portions of dispenser modules which are otherwise similar to dispenser modules  28  and  128 . 
     FIG. 24  shows a support bracket  184  similar to support bracket  112  which is attached to a dispenser module. A motor (not shown) is operative to rotate a helix  186 . A holder guide  188  similar to holder guide  86  extends in the interior of the helix  186  and is supported on a guide wall  190  in the manner previously described. 
   A guide  192  is positioned adjacent to helix  186 . Guide  192  is similar to guides  104 . Guide  192  is positioned to engage medical items  194 . Medical items  194  are generally cylindrical items such as vials, ampules or other similar types of containers. 
   A limiting member  196  is positioned on holder guide  188  in the area inside the helix  186 . Limiting member  196  which is shown in more detail in  FIG. 28 , includes an opening  198  therethrough. Opening  198  is sized to accept the holder guide in relatively close fitting relation. 
   The limiting member  198  functions to occupy a sufficient area within the interior of the helix so that the medical item  194  positioned at the front of the helix cannot fall through the central opening of the helix. This ensures that a medical item will be dispensed only upon the proper rotation of helix  186 . The limiting member  196  is particularly useful when the items being dispensed are relatively small compared to the inside diameter of the helix. The limiting member  196  may be readily removed to reconfigure the dispensing module to handle other types of medical items for which the limiting member is not required. 
     FIG. 25  shows a configuration for a porion of a dispensing module similar to that shown in  FIG. 24  which is used for dispensing larger medical items  200 . In the configuration shown in  FIG. 25  a helix  202  having a pitch suited to the size of items  200  is used. A guide  204  is also positioned to accommodate the size of the larger medical items. 
   An alternative configuration for a portion of a dispensing module is shown in FIG.  26 . In this configuration medical items  206  are dispensed. Medical items  206  are shown as relatively large ampules, but this is but one of several types of medical items that may be dispensed using this alternative configuration. Items  206  are positioned in a suitably sized helix  208 . A holder guide  210  extends adjacent to the helix  208 . Holder guide  210  is similar to holder guides previously described. The holder guide  210  may extend through the interior of the helix. As shown in  FIG. 26 , the holder guide may also serve to position and hold the medical items  206  below the holder guide in the helix. 
   A wall  212  is positioned adjacent to the helix  208  and supports the holder guide  210  in a manner similar to that previously described. A helix guide  214  is positioned adjacent to helix  208  on a side opposite wall  212 . The helix guide  214  which is shown in greater detail in  FIG. 27  is used in lieu of a guide wall. The helix guide  214  includes a pair of hook portions  216  and a pair of back tabs  218  which enable the helix guide to be selectively positioned in the first and second slots of the supporting surface of the dispenser module. 
   The helix guide provides support for helix  208  to hold it in proper position. It also operates to maintain the medical items  206  in a desirable position with one end disposed upward from the supporting surface. Positioning the medical items in this manner increases dispensing reliability. As also indicated in  FIG. 26 , the dispenser configuration used with elongated items  206  can be included in a dispensing module with a configuration similar to those shown in  FIGS. 24 and 25  for dispensing items  220 . 
   Dispenser module  30  is shown in greater detail in FIG.  14 . Dispenser module  30  includes a plurality of holders which hold generally cylindrical containers having a circular cross section. These cylindrical containers may include ampules  68  and vials  70 . Of course, other types of medical items including cartridges may be housed and dispensed. In  FIG. 14  ampules  68  are held in a holder  140  and vials  70  are held in a holder  142 . Module  30  includes a third holder  144 , however the medical items held therein are obscured by a movable cover  146 . It should be understood that each of the holders  140 ,  142  and  144  have a mechanism associated therewith as described in co-pending U.S. patent application Ser. No. 08/361,783, the disclosure of which is incorporated herein by reference. As shown in  FIG. 15 , the dispensing mechanism includes a movable front gate member  222  and a back gate member  224 . These gate members move in coordinated relation to dispense the medical items from the holder one at a time in a controlled fashion in response to electrical signals. Dispensed medications pass from the dispense location  52  at the front of each holder in the dispenser module  30 , and into the path  54  in the dispenser when the dispenser module is in the operative position. 
   As shown in  FIG. 15 , a guide  226  is selectively positionable in guide slots  228  so the dispenser may dispense items of various diameters. A thin flexible limiting member  230  extends between the guide  226  and a top plate  147 . Member  130  prevents medical items from being dislodged and passing out of the holder through the area between guide  226  and top plate  147 . 
   As best shown in  FIG. 4 , cover  146  is slidably and pivotally mounted about pivots  148 . Cover  148  further includes downward depending locking tabs  150  which engage locking pins  152 . 
   As shown in  FIGS. 4 and 14 , in the downward position of cover  146 , the cover extends above and across the holders on dispenser module  30 . Cover  146  is enabled to be moved to an up position by rotating it in a clockwise direction about pivots  148 . This can only be accomplished by moving the cover  146  forward against the biasing force of a spring  154  so that locking tabs  150  disengage from the pins  152 . This can be readily accomplished when dispenser module  30  is in the extended position out of the opening  18  of the dispenser and/or is disconnected from the dispenser as shown in FIG.  4 . 
   When dispenser module  30  is positioned within the interior area  14  of enclosure  12  as shown in  FIG. 2 , the cover  146  cannot be moved to an up position. This is because movement of the cover is prevented by either an adjacent dispenser module when the dispenser module  30  is in other than the uppermost position in the dispenser. When the dispenser module  30  is in the uppermost position as shown in  FIG. 2 , movement of the cover  146  to the up position is prevented by engagement with the components of enclosure  12  and the lock  22 . This configuration makes it difficult for an unauthorized person attempting to gain access to the medical items housed in the dispenser module to do so by extending a tool through the path  54 . This further increases the security of the preferred embodiment of the invention. 
   As shown in  FIG. 14 , medications in the holders are guided to move in a stack downwardly towards the dispensing mechanism, which is not shown because it is positioned under the cover  146  in FIG.  14 . The stack is guided to move downwardly by the biasing force of gravity guided by walls  156  which bound the sides of the enclosures. The medical items are further guided by movably positionable guides  158 . A guide is shown in detail in FIG.  19 . Guides  158  extend upwardly from a supporting surface  160  which extends across the bottom of each holder and supports the stack of medical items thereon. 
   As best shown in  FIG. 16  which shows a holder in dispenser module  30  without the cover, the supporting surface includes a plurality of slots  162  and apertures  163 . Guides  158  include tabs  165  which are selectively positionable in such slots  162  and projections  161  which are selectively positionable in apertures  163 . This enables positioning the guide  158  a desired transverse distance from an adjacent wall  156 . 
   A follower  164  is used in connection with a stack of vials  70  to assure that the vials move downwardly as they are dispensed. The follower  164  is a generally cylindrical weighted member that is rotatably movable in engaged relation with the medical items in the stack. 
   As best shown in  FIG. 17 , follower  164  includes a plurality of axially spaced annular grooves  166 . Annular grooves  166  are sized for accepting guide  158  therein. Follower  164  is of sufficient diameter and weight, and grooves  166  are configured, so that the force of gravity will cause the follower  164  to overcome any resistance to movement that may be caused by the engagement of guide  158  in a groove. This enables the follower to move downwardly and to apply a downward force to the medical items in the stack. This helps to assure their proper dispense. It should be noted that follower  164  has a slightly greater diameter on an end disposed from the grooves  166 . This enables the axis of the follower to remain parallel to the supporting surface while in engagement with a lip  167  on the guide  158 . 
   As will be appreciated with reference to  FIG. 14 , annular grooves  166  in follower  164  are spaced in a manner that corresponds to the spacing of slots  162  and apertures  163 . This enables the follower to be used with various sizes of medical items regardless of where the guide  158  may be positioned. The follower  164  has been found to be particularly advantageous when small or lightweight medical items are to be dispensed and it is desirable to provide additional biasing force on the stack to be sure that the medical items do not become caught on guides  158  or walls  156  in a manner which will prevent their proper dispense. 
   An alternative follower  232  is shown in FIG.  18 . Follower  232  is about the full width of the interior of a holder between side walls  156 . Follower  232  may be used in dispensing relatively long medical items which do not require any guides  158  to be positioned in the holder. 
   While the preferred embodiment of the present invention includes features which provide greater security against access to the medical items stored therein by unauthorized personnel, it is important that authorized personnel have ready access to the interior area  14  of enclosure  12  for purposes of replenishing medical items, taking inventory or repairing dispenser modules. The preferred embodiment of the present invention includes the lock  22  which selectively enables or prevents the opening of door  16 . 
   As best shown with reference to  FIG. 21 , door  16  has an attached connection therewith a locking post indicated  168 . Locking post  168  is sized for engagement in a slot  170  which extends in the body of lock  22 . A movable locking pawl  172  is mounted adjacent to slot  170 . 
   When door  16  is moved from the open to the closed position, locking post  168  moves into slot  170 . As locking post  168  moves into the slot it engages the locking pawl  172  and moves it to a position shown in  FIG. 21  where a portion of the pawl blocks the escape of the locking post from the slot  170 . Upon reaching the locking position, the pawl  172  is held by a spring-loaded detent or similar conventional mechanism. 
   A fundamental advantage of the preferred embodiment of the present invention is that lock  22  once in a locked condition, may be moved to an unlocked condition by two independent unlocking mechanisms. This is advantageous because an authorized user is enabled to open door  16  using one of two secure methods. The first unlocking mechanism includes an electrically actuated solenoid  174 . In response to an electrical signal, solenoid  174  is operative to move an actuator  176  of the solenoid in an inward direction relative to the solenoid, as shown in FIG.  21 . Actuator  176  rotates a member- 178  which is operative to release pawl  172 . The release of pawl  172  enables locking post  168  to move out of slot  170  and door  16  to be opened. 
   Lock  22  further includes a second unlocking mechanism which includes a mechanism that is operative to unlock the lock in response to manual manipulation. The second unlocking mechanism includes a lock cylinder  180 , which has a member  182  in connection therewith. Member  182  is enabled to be rotated by insertion of a proper key (not shown) into lock cylinder  180 . Upon rotation of the key in the lock cylinder, member  182  engages actuator  176  and moves it in a manner similar to that achieved by solenoid  174 . This enables unlocking lock  22  with a key. 
   In the system of the preferred embodiment, an authorized user who is entitled to have access to the interior area of dispenser  10  inputs data into a display terminal which identifies the user as authorized to open the dispenser. The user then inputs appropriate commands. In response to the input of the proper commands, the display terminal outputs electrical signals which are eventually transmitted to solenoid  174 , which changes lock  22  from a locked to an unlocked condition. This is generally the manner in which an authorized user will gain access to the interior area of the dispenser. 
   In the event of a malfunction which renders the display terminal inoperative or otherwise prevents the actuation of solenoid  174 , an authorized user is provided with a key for lock cylinder  180 . The insertion of the key enables opening the door  16  to accomplish the desired activity. Of course, in other embodiments enhanced security may be provided by including two different key locks and an appropriate mechanism for tying together the key locks so that both must be turned by different keys in order to open the door  16 . It should also be understood that while the preferred method of mauual manipulation used for unlocking the lock  22  is a key, in other embodiments other manually manipulatable locking mechanisms may be used. These may include for example, combination locks. 
   A sensing switch indicated  234  is positioned in the interior of the dispenser. When the door  16  is closed the switch is in contact with a strike  236 . When the door opens the strike no longer contacts the switch. The switch  234  is operative to indicate to the display terminal and the rest of the system whether the door is open or closed. The switch may be used to verify whether valid or invalid access has been gained to the dispenser. 
   If electronic access to the dispenser has been granted, the switch  234  verifies that the door  16  is opened. Likewise, it verifies that the door is closed when a user authorized to have access to the dispenser indicates to the display terminal they have completed their activity inside the dispenser. If key access is attained, a signal is generated by switch  234  which is received at the display terminal. The programming of the system preferably requires verification either immediately or subsequently that such key access is authorized. 
   Switch  234  also provides a signal which can be used to provide an indication that the dispenser has been accessed. This can be done with the system which includes the display terminal to indicate at devices or terminals connected to the system that the dispenser has been opened. Alternatively or in addition, switch  234  can be connected to a totally separate security system which monitors access to the dispensers in the system. 
   As will be appreciated from the foregoing description the preferred embodiment of the dispenser of the present invention provides flexibility in terms of reliably dispensing a wide variety of sizes and types of medical items. The dispenser is constructed to provide enhanced security against access to the medical items stored therein by unauthorized persons. However authorized persons are readily enabled to gain access to the dispenser. 
   Thus, the new dispensing apparatus for medical items achieves the above stated objectives, eliminates difficulties encountered in the use of prior devices and systems, solves problems and attains the desirable results described herein. 
   In the foregoing description certain terms have been used for brevity, clarity and understanding, however no unnecessary limitations are to be implied therefrom because such terms are for descriptive purposes and are intended to be broadly construed. Moreover, the descriptions and illustrations herein are by way of examples and the invention is not limited to the exact details shown and described. 
   In the following claims any feature described as a means for performing a function shall be construed as encompassing any means capable of performing the recited function and shall not be deemed to be limited to the particular means shown in the foregoing description or mere equivalents thereof. 
   Having described the features, discoveries and principles of the invention, the manner in which it is constructed and operated, and the advantages and useful results attained; the new and useful structures, devices, elements, arrangements, parts, combinations, systems, equipment, operations, methods, processes and relationships are set forth in the appended claims.