Abstract:
A vial docking station for simultaneously sliding the spouts of a plurality of liquid medicament vials into an engaged position with matching receptacles of a like plurality of liquid reconstitution diluent bags.

Description:
TECHNICAL FIELD  
         [0001]    The invention relates to a vial docking station for simultaneously sliding the spouts of a plurality of liquid medicament vials into an engaged position with matching receptacles of a like plurality of liquid reconstitution diluent bags.  
         BACKGROUND OF THE ART  
         [0002]    In hospital pharmacies, a common activity is to prepare several intravenous delivery bags with saline solutions for example to be mixed with various liquid medicaments to the specification of doctors. Often, the liquid medicines are provided in vials or glass bottles with a rubber sheet diaphragm across the spout of the bottle sealed with a metal rim and removable seal. The liquid medicines can be accessed by hypodermic needle for example, piercing through the rubber diaphragm and withdrawing liquid medicine into a hypodermic needle. Also commonly in hospitals, the vials are provided in measured doses by the drug manufacturer and the hospital pharmacy prepares intravenous solutions by engaging the spouts of the vials with matching receptacles on the sealed sterile diluent bags. The receptacles include sliding or telescoping means to engage a piercing needle on the receptacle and release the medicine from the vials into the saline solution in the diluent bag by permitting air to pass one way into the vial and thereby releasing the liquid through the needle.  
           [0003]    Manually engaging the vials with receptacles of diluent bags involves many risks including physical injury or biological contamination from sharp needles, contamination of adjacent atmosphere with powerful or toxic medicines, and exposure of pharmacy workers to long term low concentrations of drugs. In order to address these risks, the prior art includes various mechanical devices to ensure safe engagement of vials with the receptacles and includes mechanical devices that can be positioned under exhaust hooks to avoid contamination.  
           [0004]    U.S. Pat. No. 5,037,390 to Raines et al. shows a method of preparing diluent solution bags from a number of different vials of medicines of different sizes. The fluid medicament from the vials is conducted through a perforated needle in a one way valve into a manifold, which conducts the mixture of medicines to a diluent bag for delivery to the patient.  
           [0005]    U.S. Pat. No. 6,070,761 to Bloom et al. shows a complex automatic system for mixing medicines for multiple vials that are delivered through needles into a plastic cassette with various channels and vials are mixing and delivering the medicament to an automatic delivery system.  
           [0006]    Simple manual mechanisms for engaging a diluent bag with piercing needle and vials minimizing the risk of injury and exposure are shown in several patents such as U.S. Pat. No. 5,826,713 to Sunago et al., U.S. Pat. No. 5,478,337 to Okamoto et al. and U.S. Pat. No. 5,364,386 to Fukuoka et al. Apart from the examples mentioned above, it is considered well known to those in the relevant art that various devices are available for connecting vials containing medicaments with flexible diluent bags containing saline solutions.  
           [0007]    A significant disadvantage of the prior art devices is the high cost and mechanical complexities. Due to these disadvantages, many hospital pharmacies rely on the physical labour of pharmacists to connect vials with receptacles individually. This method leads to fatigue and mistakes, personal injury and exposure to biological hazards as well as concentrated medicines which impose unacceptable risks to workers in hospital pharmacies as a result.  
           [0008]    An unrecognised, but major cause of illness and some times death is human error in preparing medicines, which are delivered in the wrong concentration or to the wrong patient.  
           [0009]    It is an object of the present invention to provide a simple low cost reliable tool for engaging vials of various sizes to diluent bags thus avoiding human contact and physical exertion as much as possible.  
           [0010]    It is a further object of the invention to provide a mechanical system wherein vials of different sizes can be prepared in a ready position and double-checked before mixing for example with bar code readers in an optical checking system.  
           [0011]    It is a further object of the invention to provide optional manually operated vial docking station and pneumatic or hydraulically operated version without significant modification to the mechanism.  
           [0012]    Further advantages of the invention will be apparent from the following detailed description and accompanying drawings.  
         DISCLOSURE OF THE INVENTION  
         [0013]    The invention provides a vial docking station for simultaneously sliding the spouts of a plurality of liquid medicament vials into an engaged position with matching receptacles of a like plurality of liquid reconstitution diluent bags. The vial docking station has a support frame that can be mounted to a wall or within an exhaust hood to reduce the risk of exposure.  
           [0014]    The frame has a stationary bag mounting block with a series of spaced apart receptacle mounts. The mounts are C-shaped for suspending the diluent bags from their flexible inlet tube and receptacles below the mounting block. For different sizes or designs of receptacles, the mounts can include replaceable inserts or ferrules of different designs.  
           [0015]    A header block is slidably mounted to the frame and has an equal number of plungers that are used to hold vials in an upturned position and to force the vial spout into sliding engagement with the receptacle. Each plunger is spring loaded or biased to firmly hold and guide the base of an associated vial in a ready position. In this position the vial is upturned to flow out under gravity when the seal diaphragm is pierced with the needle of the receptacle. The vial spout is aligned with the receptacle ready to be forced into sliding engagement with the plungers. Each plunger is manually individually operable between the ready position and a retracted position wherein the vial base is manually lifted against the force of gravity and spring load to be disengaged from the plunger.  
           [0016]    Plunger clamps are disposed on the header block, for releasably clamping each plunger to move with the header block. A manually operated or mechanically operated actuation mechanism is mounted to the frame and engages the plunger clamps and the moveable header block for moving the header block progressively from the ready position forward to the engaged position, and rearward to a withdrawn position and for actuating the plunger clamps during movement between the ready position and the withdrawn position.  
           [0017]    The plungers have a head with a conical self-centering vial base mating socket and a rod slidably mounted to the header block. The plunger head is spring loaded toward the bag mounting block to hold the vials ready in an upturned position above the bag receptacles.  
           [0018]    The plunger clamp has a lock lever pivotally mounted to the header block for rotation about an axis transverse to the plunger rod. The rod extends through an aperture through the lock lever and the lock lever can move between a free sliding position and a clamped position wherein lock lever is disposed relative to the plunger rod with peripheral edges of the aperture gripping an outer surface of the rod. The offset aperture therefore binds or grips the cylindrical rod.  
           [0019]    Further advantages of the invention will be apparent from the following detailed description and accompanying drawings. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0020]    In order that the invention may be readily understood, two embodiments of the invention are illustrated by way of example in the accompanying drawings.  
         [0021]    [0021]FIG. 1 is a front elevation view of a manually operated embodiment of the invention showing a rectangular frame with bag mounting block suspending four diluent bags by their receptacles and including four vials in an inverted or upturned position aligned with the receptacles, the vials being of different sizes adapted with the spring loaded plungers.  
         [0022]    [0022]FIG. 2 is a perspective view of the manual embodiment shown in FIG. 1.  
         [0023]    [0023]FIG. 3 is a detailed view of the manual embodiment with the crank shaft, cam shaft and lock levers positioned on the movable header block spring loaded upwardly from the stationary bag mounting block.  
         [0024]    [0024]FIGS. 4, 5,  6 , and  7  show the progressive downward motion of the crank arm of the manual embodiment which is manually rotated clockwise to simultaneously force the movable headed block downwardly and clamp the plungers to move with the header block by releasing the lock levers to bind with the cylindrical rods of the plunger.  
         [0025]    [0025]FIGS. 8 and 9 show detailed view of the lock lever of the manual embodiment spring loaded to an upward position and pivoted to allow the plunger rod to slide freely (in FIG. 8) and to bind the slide rod (shown in FIG. 9).  
         [0026]    [0026]FIG. 10 shows a pneumatically or hydraulically actuated embodiment of the invention (similar to the view of the manual embodiment of FIG. 2 but shown from the rear rather than front view) with a single central actuating cylinder engaging the movable header block.  
         [0027]    [0027]FIG. 11 shows a detailed view of the end cam followers engaging a pin mounted to the frame for rotating the cam shaft as the cam shaft and header beam move downwardly thereby releasing the spring loaded lock levers to bind on the rods of the plunger.  
         [0028]    [0028]FIGS. 12, 13, and  14  show the progressive rotation of the cam shaft with cam follower engaging the pin projecting from the frame side wall and showing the releasing of the lock levers spring loaded to a position which binds at an angle to the rod of the plunger.  
         [0029]    [0029]FIGS. 16 and 17 show detailed sectional views of the cam shaft with cam lobe that engages and disengages the lock lever in FIG. 16 showing the lock lever disengaged from the plunger rod, whereas FIG. 17 shows the binding between the aperture in the lock lever and the cylindrical plunger rod.  
     
    
       [0030]    Further details of the invention and its advantages will be apparent from the detailed description included below.  
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0031]    With reference to FIGS. 1 and 2, the invention provides a manually operated vial docking station that accommodates vials  1  of different common sizes and simultaneously slides the spout of the inverted or upturned vials  1  into an engaged position with matching receptacles  2  of a spaced apart series of diluent bags  3 .  
         [0032]    The vial docking station includes in the embodiment illustrated a rectangular frame  4  for hanging on a wall in a vertical position. It will be understood that different embodiments can be provided for table top use or in a horizontal position with equal advantage. The frame  4  includes a horizontal bag mounting block  5  with a spaced apart series of receptacle mounts  6 . The embodiment illustrated shows the bag mounting block  5  fixed in position to side walls  7 . The stationary portions of the frame also include middle beam  8  and top beam  9 .  
         [0033]    A slidable header block  10  is manually operated with crank arm  11  in a manner, which will be described in detail below. The header block  10  slides on vertical pins  12  and is spring loaded to an upward position against middle beam  8  with springs  13 .  
         [0034]    The header block  10  also includes plungers  14  that are clamped and unclamped to move simultaneously up and down with the header block  10  thereby exerting force on the bottom of the vials  1  sufficient to slidably engage the spout of the vials in the receptacles  2 .  
         [0035]    The plungers  14  include a head  15  and a rod  16 . The rods are guided but otherwise free to slide through middle beam  8  and slide through header block  10  when unclamped. Clamps on the header lock  10  that secure the rods  16  to the header block  10  are actuated by the manual motion of the crank arm  11  once the vials are manually placed in position shown in FIGS. 1 and 2. A spring  17  engaging a collar  18  on the slidable rods  16  together with the gravitational force of the weight of the plunger  14  hold the vials  1  in a ready position. The operator grasps the plunger head  15  and lifts upward to a withdrawn position against the force of the spring  17  to insert and remove the vials  1 . In the embodiment shown the plunger heads  15  have a conical self centering socket  19  for locating and holding the base of any size of vial  1 .  
         [0036]    [0036]FIGS. 4, 5,  6 , and  7  show the manual embodiment of the invention in a sectional view through middle beam  8  and movable header block  10 . The header block  10  is mounted to middle beam  8  of the frame on pins  12  with spring  13  to slide up and down during manual operation of the crank arm  11  in a clockwise direction progressing from FIG. 4 through FIG. 7.  
         [0037]    Rotation of the crank arm  11  rotates crank shaft  20  and lever arm  21 , which engages cam follower  22  thereby rotating cam shaft  23 . Rotation of the cam shaft  23  with cam lobe  28  releases spring loaded lock lever  24  to the position shown in FIGS. 6 and 7 binding on the rod  16  extending through lock lever  24 . Further rotation of the lever arm  21  engages a top surface of the header block  10  pushing the plungers  14  downwardly to the engaged position as shown in FIG. 7.  
         [0038]    To recap therefore the header block  10  mounts to the frame with series of plungers  14 , each of which is biased to engage the base of an associated vial  1  in a ready position as shown in FIGS. 1 and 2.  
         [0039]    Each plunger  14  is manually individually operable between the ready position shown in FIG. 1 and a retracted position for disengaging the vial base from the plunger  14 .  
         [0040]    The plunger clamping position is illustrated in FIGS. 8 and 9 in detail. Plunger rods  16  engage through the movable header block  10  and are spring loaded to a downward position with springs  17 . FIGS. 8 and 9 show the details of plungers clamps disposed on the header block  10  to releasably clamp each plunger rod  16  and inhibit relative motion between the plunger  14  and the header block  10 . The manual actuation mechanism comprising crank arm  11 , crank shaft  20  and lever arm  21  as described above serve to engage the plunger clamps, the header block  10  or the bag mounting block  5  and move the header block  10  relative to the bag mounting block  5  from the ready position shown in FIG. 1 to the engaged position shown in FIG. 7 and rearwardly withdraw the header block  10  under the force of lift springs  13  automatically disengaging the plunger clamps.  
         [0041]    As seen in FIGS. 8 and 9, the plunger clamps comprise a lock lever  24 , which is pivotally mounted on pin  25  to rotate about an axis transverse to the plunger rod  16 . The rod  16  extends through an aperture  26  extending through the lock lever  24 . The lock lever  24  moves between the free sliding position shown in FIG. 24 and clamped position shown in FIG. 9. In the clamped position, the lock lever  24  is disposed relatively to the plunger rod  16  such as peripheral edges of the aperture  26  grip the outer cylindrical surface of the rod  16 . The lock lever  24  is spring loaded to the upward position of FIG. 9 by spring  27 . Since the aperture  26  in the sliding free position shown in FIG. 8 closely matches the outer cylindrical surface of the rod  16 , only a slight offset motion (as illustrated in FIG. 9) is required in order to tightly bind the rod  16  in the aperture  26  and prevent movement relative to the header block  10 . Rotation of the cam shaft  24  mounted to the header block  10  causes the cam lobe  28  to rotate (as shown between FIG. 8 and FIG. 9) in a counter clockwise motion thereby freeing the spring  27  to pivot the lock lever  24  about pin  25 .  
         [0042]    As best seen in the progression shown in FIGS. 4, 5,  6 , and  7 , the cam shaft  23  includes a cam follower  22  for rotating the cam shaft  23  as the header block  10  progresses between the ready position, a fully engaged position and a withdrawn position. In the withdrawn position, the vials  1  can be removed by raising the plunger  14  manually and lifting the empty vial from engagement with the receptacle  2 . At this point, the bag  3  with sealing solution and mixed medicament can be delivered to patient care providers.  
         [0043]    As seen in the progression between FIGS. 4, 5,  6 , and  7 , manual rotation of the crank shaft  20  with crank arm  11  rotates lever arm  21 , which serves two functions. Firstly, interaction with cam follower  22  and lever arm  21  serves to rotate cam shaft  23  thereby releasing cam lobe  28  from engagement with lock lever  24 . As shown in FIGS. 6 and 7, releasing lock lever  24  results in binding of the plunger rods  16  with the lock lever  24  as best seen in FIGS. 8 and 9. Further, manual rotation of the lever arm  21  as shown in FIGS. 6 and 7 pushes on the top surface of the header block  10  and brings the header block  10  with attached plungers downward against the force of spring  13  compressed between the header block  10  and stationary middle block  8 .  
         [0044]    [0044]FIGS. 10 through 17 disclose a second embodiment of the invention that is not manually operated but rather is operated primarily through use of a pneumatic or hydraulic cylinder  29 . As shown in FIG. 10, the cylinder actuates motion of the header block  10  sliding it vertically with respect to the stationary middle block  8  in a manner similar to that described above in respect of the manually operated embodiment.  
         [0045]    In the mechanically operated embodiment, the mounting of the bags  3  in the bag mounting block  5  and the motion of the plungers  14  is identical to that described above. However, in the mechanically operated version there is no crank shaft  20 , lever arm  21  or crank arms  11 . The functions performed by these manually operated elements to rotate the cam shaft  23  and move the header block  10  are performed as follows.  
         [0046]    FIGS.  12 ,  13 , 14 , and  15  show the progressive motion of the plunger  14  as the plunger rod  16  is clamped with lock lever  24  through the action of rotating cam shaft  23  thereby releasing engagement between the cam lobe  28  and lock lever  24 , in a manner similar to that described above. FIGS. 16 and 17 show means by which the rods  16  and lock levers  24  are engaged and disengaged under the action of spring  27  as the lock lever  24  rotates about pin  25 .  
         [0047]    However, as seen in the detail of FIG. 11 as well as FIGS. 12 through 15, the rotation of the cam shaft  23  is performed in a different manner. The up and down motion of the header block  10  is controlled by the stroke of the cylinder  29 . Due to the possibility of physical injury to operators using an automated device, it is likely necessary to ensure that both of the operator&#39;s hands are out of the way of the plungers  14  and header block  10  before the cylinder  29  is activated. Therefore conventional twin push buttons are recommended for safety reasons.  
         [0048]    The progression shown in FIGS. 12 through 15 and detail of the end view of the cam shaft  23  in FIG. 11 indicate that each of the frame side walls  7  include a pin  30 . In the mechanical operated embodiment, the cam follower  22  mounted to the cam shaft  23  is located at the two ends of the cam shaft  23  and has a different profile to interact with the pin  30  projecting from the frame side wall  7 . As shown in the progression through FIGS. 12, 13,  14  and  15 , the interaction between the moving cam surface of cam follower  22  with the stationary pin  30  results in a simple mechanism which rotates the cam shaft  23  and thereby engages and disengages the cam lobe  28  from the top surface of each lock lever  24 .  
         [0049]    As described above, the invention includes both a manually operated version in FIGS.  1 - 9  and a mechanically operated version in FIGS.  10 - 17 , both of which utilize many common features such as plungers  14 , movable header block  10  and lock levers  24 . The invention overcomes the disadvantages of the prior art in enabling simple accommodation of various different sizes of vials simultaneously as shown in FIG. 1 with a simple mechanism that is inexpensive and easy to operate.  
         [0050]    Although the above description relates to a specific preferred embodiment as presently contemplated by the inventor, it will be understood that the invention in its broad aspect includes mechanical and functional equivalents of the elements described herein.