Abstract:
An infusion pump for transferring fluid through tubing of an administration set connected to the pump, where the pump includes a housing and a pumping mechanism mounted to the housing. The pumping mechanism includes a plurality of pumping fingers, a motor for sequentially, reciprocally moving the plurality of pumping fingers, and an occlusion sensor configured to detect reverse loading of the tubing to the pumping mechanism. In operation, the occlusion sensor causes at least one of a triggering of an alarm and prevention of the operation of the pumping mechanism when the sensor detects that the administration set tubing is reverse loaded to the pumping mechanism.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a system for protecting against misloading of an infusion system, and more particularly, to a system including misloading protection features that enable the proper connection of an administration set to an infusion pump. 
       BACKGROUND 
       [0002]    Infusion systems deliver fluids, including nutrients and medications, to a patient. Such systems include pumps programmed to supply these fluids to patients in predetermined dosages and at designated time intervals. Errors in administration of the fluids through an infusion system can result from many causes including misloading or misconnection of an administration set to the system. These issues can lead to over or under infusion of the fluids to the patient, missed treatments or delayed treatments that can significantly affect a patient&#39;s health and recovery. As a result, guidelines have been established to enhance the safety of infusion systems. 
         [0003]    There are several safety checks that clinicians typically perform such as “line management” or “line tracing” to help eliminate misconnections or misloading. Setting up such infusion systems and detailed connection management procedures imposes a time burden on the clinician and is prone to errors, particularly as the complexity of a patient&#39;s overall infusion system increases. That is, the multiple administrations sets, medications, junctions, access ports, pump channels in infusion systems, increases the amount of time required to perform infusion system safety checks and also introduces additional opportunities for error. 
         [0004]    Accordingly, there is a need for a system that facilitates proper connection of an administration set to an infusion system while reducing human error. 
       SUMMARY 
       [0005]    The present infusion pump includes misloading protection features that guide the proper connection of an administration set to an infusion pump while helping to minimize human error. 
         [0006]    In an embodiment, an infusion pump for transferring fluid through tubing of an administration set is provided where the pump includes a housing and a pumping mechanism mounted to the housing. The pumping mechanism includes a plurality of pumping fingers, a motor for sequentially, reciprocally moving the plurality of pumping fingers, and an occlusion sensor configured to detect reverse loading of the tubing to the pumping mechanism. The occlusion sensor causes the motor to turn off when the occlusion sensor detects the reverse loading of the tubing to the pumping mechanism. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view showing an infusion pump according to an embodiment of the present invention; 
           [0008]      FIG. 2  is a perspective view showing the infusion pump of  FIG. 1  where the door is in the open position; 
           [0009]      FIG. 3  is a perspective view showing an embodiment of an administration set that is connected to the infusion pump of  FIG. 1 ; 
           [0010]      FIG. 4  is a fragmentary, perspective view showing tubing of the administration set of  FIG. 3  inserted through and clamped by a slide clamp of the infusion pump of  FIG. 1 ; and 
           [0011]      FIG. 5  is a fragmentary, front view of an embodiment of a pumping mechanism associated with the infusion pump of  FIG. 1 , where the pumping mechanism includes an occlusion sensor and a valve. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    Referring to  FIGS. 1-5 , an infusion delivery system including an infusion pump  50  is used to deliver fluids, such as medications or nutrients, to a patient in predetermined quantities and at periodic time intervals. The infusion pump  50  may be a small portable pump or a larger pump, such as the infusion pump disclosed in U.S. Pat. No. 5,018,945, which is incorporated herein by reference. As shown in  FIG. 1 , the infusion pump  50  includes a housing  52 , a door  54  pivotally connected to the housing and a display  56  and a keypad  58 , among other inputs, on the door. The display  56  and the keypad  58  are used to program the infusion pump, and more specifically, a processor  60  in the pump to set the fluid delivery amount and time interval, which in turn, is communicated to pumping mechanism  62 . 
         [0013]    Fluids move to and from the infusion pump  50  through a fluid administration set  64  shown in  FIG. 3 . The administration set  64  is attached to the pump  50  by routing a portion of the tubing  66  of the administration set  64  between the door  54  and the housing  52 . Preferably, the administration set  64  includes a drip chamber  68  directly connected to a fluid container (not shown), such as an intravenous fluid bag, a slide clamp  70  used to clamp a portion of the tubing  66  and control the flow of the fluid through the tubing, a roller clamp  72  also used to control the flow of the fluid, a Y-site connector  74  and a luer lock or luer slip  76  at an end of the administration set  64  where the luer lock is connected to a needle inserted in a patient for delivering the fluid to the patient. A portion of the administration set tubing  66 , and more specifically, the portion of the tubing  66  between the slide clamp  70  and the roller clamp  72 , is inserted in channels  78  defined by the housing  52  and positioned over the pumping mechanism  62 . As described below, the pumping mechanism  62  includes a series of reciprocating pumping fingers  80  that contact the tubing  66  for controlling the amount of the fluid delivered to the patient. 
         [0014]    During administration of a fluid to a patient, it is critical to prevent free flow of the fluid to the patient. Free flow occurs when a fluid is allowed to flow unrestricted to the patient resulting in too much of the fluid to be supplied to the patient, i.e., an over infusion. To help prevent free flow of the fluid through the administration set  64 , the slide clamp  70  is attached to the tubing  66  of the administration set. As shown in  FIG. 4 , the slide clamp  70  includes a body  82  having a central opening  84  with a wide portion  86  and a narrow portion  88 . The tubing  66  is moved into the narrow portion  88  of the slide clamp opening  84  to clamp or crimp the tubing and prevent free flow of the fluid through the tubing. This is particular critical when the administration set  64  is being inserted in or otherwise attached to the infusion pump  50  to deliver a fluid to the patient. 
         [0015]    Referring now to  FIG. 5 , another issue that results from the set up of the infusion pump  50  is a reverse loading condition where the administration set  64  is connected to the infusion pump so that the fluid flow is in a reverse or opposite direction to the desired fluid flow direction, i.e., from the fluid container to the patient. With reverse loading, the fluid flows from the patient to the fluid container thereby posing a health risk to the patient. To overcome reverse loading, an embodiment of the present infusion pump  50  includes an occlusion sensor or pressure sensor  90  associated with the pumping mechanism  62  and a valve  92  associated with pumping finger  80   c  of the pumping fingers  80 . 
         [0016]    In the illustrated embodiment, the administration set is connected to the infusion pump  50  so that the slide clamp  70  is open while the roller clamp  72  is closed. A tube misload sensor  80   b  performs an initial check to detect and determine if the tubing  66  of the administration set is misloaded on the pumping mechanism as described above. If the tubing  66  is loaded properly, a designated rate, preferably a high flow rate, such as 999 milliliters per hour (mL/hr), is programmed into the processor  60  of the infusion pump  50  to allow quick pressure build up in the pumping mechanism  62  to minimize sensor detection time. Also, the valve  92  occludes or blocks the flow of fluid through the tubing  66  adjacent to pumping finger  80   c.  Next, the processor  60  sends a signal to the pumping fingers  80  to run quickly through a pumping sequence from pumping finger  80   a  to pumping finger  80   c.  When there is normal loading of the administration set  64  to the infusion pump  50 , the occlusion sensor  90  detects a downstream occlusion at pumping finger  80   c.  Alternatively, if there is reverse loading of the administration set  64 , i.e., the roller clamp  72  is linked to the top side of the pumping mechanism  62  (connected to the tubing prior to pumping finger  80   a ), the occlusion sensor  90  detects an upstream occlusion due to the roller clamp  72 . Since the signals associated with normal loading and reverse loading of the administration set  64  are different, the occlusion sensor  90  is able to detect when the administration set  64  is reverse loaded. After the initial loading check, if the administration set  64  is properly or normally loaded, the motor  96  does a short reverse run, i.e., the pumping finger sequence goes from pumping finger  80   c  to pumping finger  80   a,  to avoid a bolus to the patient. A start key on the keypad  58  of the infusion pump  50  is then pressed which causes the valve  92  associated with pumping finger  80   c  to unocclude the tubing  66  of the administration set  64  and allow normal infusion or flow of the fluid. If reverse loading of the administration set  64  to the infusion pump  50  is detected by the occlusion sensor  90 , the occlusion sensor sends a signal to the processor  60 , which in turn, triggers an alarm  61  ( FIG. 1 ), such as an audio indicator, a visual indicator, a tactile indicator or any combination of these indicators or cues, to alert a user that the administration set is reverse loaded. It should be appreciated that any suitable alarms or indicators may be used to alert the user. The processor  60  may also prevent operation of the infusion pump  50  when reverse loading is detected by the occlusion sensor  90 . For example, the processor  60  may deactivate or shut off the pumping mechanism motor  96  ( FIG. 2 ). 
         [0017]    In another embodiment, the administration set  64  is loaded or connected to the infusion pump  50  where both the slide clamp  70  and the roller clamp  72  are opened or in an open position. Similar to the embodiment above, the tube misload sensor  80   b  determines if the tubing  66  of the administration set  64  has been misloaded on the pumping mechanism  62 . If the tubing  66  is loaded properly, a designated flow rate, and preferably a high flow rate, such as a flow rate of 999 milliliters per hour (mL/hr), is set or programmed into the processor  60  to allow quick pressure build up in the pumping mechanism  62  to minimize sensor detection time. The pumping mechanism  62  then does a short reverse run where the pumping finger sequence goes from pumping finger  80   c  to pumping finger  80   a  and is held for a short period of time and then released. As described above, there are two possible loading conditions, normal loading and reverse loading. With normal loading, the administration set tubing  66  positioned between pumping finger  80   a  and pumping finger  80   c  is refilled with the fluid. With reverse loading, the tubing  66  between pumping finger  80   a  and pumping finger  80   c  is not refilled with the fluid. In this regard, the misload sensor  80   b  is able to detect force or pressure. Therefore, since the signals associated with normal loading and misloading are different, the sensor  80   b  can also detect when the administration set  64  is normally loaded or reverse loaded and trigger an alarm or other suitable indicator as described above if reverse loading is detected. It should be appreciated that the misload sensor  80   b  is preferably a highly pressure sensitive sensor to detect the force/pressure difference between normal loading and misloading of the administration set  64 . 
         [0018]    The present infusion pump  50  includes misloading protection features that help prevent free reverse loading of an administration set to the pump. The protection features of the present infusion pump enable users to properly set up of the infusion pump and deliver fluid to a patient while minimizing human error. 
         [0019]    While the principles of the present infusion pump have been described above in connection with specific apparatus and applications, it is to be understood that this description is made only by way of example and not as a limitation on the scope of the claims following below.