METHOD FOR CALIBRATING A SYRINGE PUMP, SYRINGE PUMP AND APPARATUSES

Abstract

The present disclosure describes a medical syringe pump and a method for calibrating a medical syringe pump. In some cases the medical syringe pump is configured and/or prepared to execute the method according to the present disclosure, or has been calibrated accordingly. This disclosure also describes a blood treatment apparatus which comprises such syringe pump or is connected to such syringe pump. Furthermore, the present disclosure describes a digital storage medium and/or a computer program product as a computer program.

Claims

1-25. (canceled)

26. A method for calibrating a medical syringe pump, the syringe pump comprising: a syringe receptacle configured to receive a syringe comprising a syringe cylinder and a plunger that is movable within the syringe cylinder between a first end position and a second end position, wherein the plunger is connected to a plunger rod; a slide movable in motor steps and having a toggle for receiving a section of the plunger rod or for connecting thereto, wherein a section of the slide is arranged to be movable maximally between a first end stop and a second end stop relative to the syringe receptacle, and wherein the syringe pump is configured to move the slide in motor steps; a counting device for counting the number of motor steps by which the slide is being moved; a first sensor and a second sensor, both arranged along a shifting path of the plunger or along a travel or movement path of the slide; a control device configured for moving the slide according to control instructions; a storage device; and an input device for entering control instructions and/or other data by a user, wherein the method for calibrating the syringe pump comprises: a) moving, at a first speed, a section of the slide to a position between the first sensor and the second sensor; b) moving, at a second speed, the toggle by the slide such that the plunger, when a syringe is inserted, would reach or come to a first end position, or until a predetermined section of the slide, reaches the first end stop, wherein, when the predetermined section of the slide reaches or passes by the position of the second sensor, the number of motor steps given or output for or at this position by the counting device is determined as a first count value, and wherein, when the plunger reaches the first end position or when the section of the slide reaches the first end stop, the motor steps, which have been counted by the counting device until reaching the position of the first end position or of the first end stop are determined as a second count value; c) calculating a calibration value for the second sensor based on the first count value and the second count value; d) storing, by the storage device, the calibration value for the second sensor; e) moving the toggle at the second or a third speed towards the second end position; f) determining the number of motor steps output by the counting device as a third count value upon reaching the position of the first sensor or passing it by the predetermined section of the slide; g) calculating a calibration value for the first sensor based on the third count value; and h) storing, by the storage device, the calibration value for the first sensor.

27. The method of claim 26, further comprising entering at least information about a particular type of the syringe using the input device and storing this information by the storage device.

28. The method of claim 26, further comprising resetting the counting device to zero or to a predetermined start value or number.

29. The method of claim 26, wherein the calculating the calibration value for the first sensor is also based on a further value from the group consisting of: the first count value, the second count value, and the calibration value of the second sensor.

30. The method according to claim 26, wherein to proceed according to step a) the section of the slide is first moved towards the first end stop, and wherein moving the section of the slide at the second speed continues after either the position of the second sensor or the first end stop is reached, wherein, after the position of the second sensor or of the first end stop has been reached, the section of the slide is automatically moved by a predetermined number of motor steps towards the second end stop, prior to being subsequently further moved according to step b).

31. The method according to claim 26, wherein the first speed is higher than the second speed and/or than the third speed.

32. The method according to claim 26, wherein the third speed is higher than or identical to the second speed.

33. The method according to claim 26, wherein the determined number of motor steps is offset with a compensation value and therefore is entered or included compensated in the calculation of the calibration values of the first sensor and/or the second sensor according to steps c) and g).

34. The method according to claim 26, wherein the corrected calibration values of the first sensor and/or of the second sensor are verified or checked for plausibility.

35. The method according to claim 26, wherein the first sensor and/or the second sensor is a magnet field sensor, an optoelectronic sensor, and/or part of a resistance trail or path which functions according to the principle of a potentiometers.

36. The method according to claim 26, wherein the slide comprises a permanent magnet being movable to the section of the slide in a constant distance.

37. The method according to claim 26, wherein the information about the particular syringe type includes at least the distance between the first end position and the second end position and/or a correction factor and/or an offset.

38. The method according to claim 26, wherein the predetermined section of the slide includes a permanent magnet, and wherein the moving, at the second speed, the toggle by the slide is performed until the permanent magnet reaches the first end stop.

39. A medical syringe pump, comprising a syringe receptacle configured to receive a syringe comprising a syringe cylinder and a plunger that is movable within the syringe cylinder between a first end position and a second end position, wherein the plunger is connected to a plunger rod; a slide movable in motor steps and having a toggle for receiving a section of the plunger rod or for connecting thereto, wherein a section of the slide is arranged to be movable maximally between a first end stop and a second end stop relative to the syringe receptacle, and wherein the syringe pump is configured to move the slide in motor steps; a counting device for counting the number of motor steps by which the slide is being moved; a first sensor and a second sensor, both arranged along a shifting path of the plunger or along a travel or movement path of the slide; a control device configured for moving the slide according to control instructions; a storage device; and an input device for entering control instructions and/or other data by a user, wherein the control device is configured to execute a calibration method comprising: a) moving, at a first speed, a section of the slide to a position between the first sensor and the second sensor; b) moving, at a second speed, the toggle by the slide such that the plunger, when a syringe is inserted, would reach or come to a first end position, or until a predetermined section of the slide, reaches the first end stop, wherein, when the predetermined section of the slide reaches or passes by the position of the second sensor, the number of motor steps given or output for or at this position by the counting device is determined as a first count value, and wherein, when the plunger reaches the first end position or when the section of the slide reaches the first end stop, the motor steps, which have been counted by the counting device until reaching the position of the first end position or of the first end stop are determined as a second count value; c) calculating a calibration value for the second sensor based on the first count value and the second count value; d) storing, by the storage device, the calibration value for the second sensor; e) moving the toggle at the second or a third speed towards the second end position; f) determining the number of motor steps output by the counting device as a third count value upon reaching the position of the first sensor or passing it by the predetermined section of the slide; g) calculating a calibration value for the first sensor based on the third count value; and h) storing, by the storage device, the calibration value for the first sensor.

40. The syringe pump of claim 39, wherein the calibration method further comprises: entering information about a particular type of the syringe using the input device; and storing the information about the particular type of the syringe by the storage device.

41. The syringe pump of claim 39, wherein the calibration method further comprises resetting the counting device to zero or to a predetermined start value or number.

42. The syringe pump of claim 39, wherein the calculating the calibration value for the first sensor is also based on a further value from the group consisting of: the first count value, the second count value, and the calibration value of the second sensor.

43. The syringe pump of claim 39, wherein to proceed according to step a) the section of the slide is first moved towards the first end stop, and moving the section of the slide at the second speed continues after either the position of the second sensor or of the first end stop is reached, wherein, after the position of the second sensor or of the first end stop has been reached, the section of the slide is automatically moved by a predetermined number of motor steps towards the second end stop, prior to being subsequently further moved according to step b).

44. The syringe pump of claim 39, wherein the first speed is higher than the second speed and/or than the third speed.

45. The syringe pump of claim 39, wherein the third speed is higher than or identical to the second speed.

46. The syringe pump of claim 39, wherein the determined number of motor steps is offset with a compensation value and therefore is entered compensated in the calculation of the calibration values of the first sensor and/or the second sensor according to step c) and g).

47. The syringe pump of claim 39, wherein the thus corrected calibration values of the first sensor and/or of the second sensor are verified or checked for plausibility.

48. The syringe pump of claim 39, wherein the first sensor and/or the second sensor is a magnet field sensor or an optoelectronic sensor.

49. The syringe pump of claim 39, wherein the slide comprises a permanent magnet being movable in a constant distance to the section of the slide.

50. The syringe pump of claim 39, wherein the information about the particular syringe type includes at least the distance between the first end position and the second end position and/or a correction factor and/or an offset.

51. The syringe pump of claim 39, wherein the syringe pump comprises a heparin syringe pump.

52. The syringe pump of claim 39, wherein the syringe pump is calibrated according to steps a) through h) of the calibration method.

53. The syringe pump of claim 39, wherein the predetermined section of the slide includes a permanent magnet, and wherein the moving, at the second speed, the toggle by the slide is performed until the permanent magnet reaches the first end stop.

54. A blood treatment apparatus comprising, or being connected in signal communication to, the medical syringe pump of claim 39.

55. The blood treatment apparatus according to claim 54, designed as a peritoneal dialysis apparatus, a hemodialysis apparatus, a hemofiltration apparatus, a hemodiafiltration apparatus, or an apparatus for the chronic renal replacement therapy or continuous renal replacement therapy.

56. A digital storage medium with electronically readable control signals configured to interact with a programmable computer system such that the machine-induced steps of a method according to claim 26 are prompted.

57. The digital storage medium of claim 56, wherein the digital storage medium comprises a floppy disk, a CD, a DVD, or an EPROM.

58. A computer program product, as a signal wave or program code stored on a machine-readable storage medium, for prompting the machine-induced steps of the method according to the present invention according to claim 26, when the computer program product runs on a computer.

59. The computer program product of claim 58, wherein the computer program product comprises the program code stored on the machine-readable storage medium.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0085] The present disclosure is exemplarily explained below with regard to the accompanying drawings in which identical reference numerals refer to the same or similar components. In the figures, the following applies:

[0086] FIG. 1 shows a conventional syringe;

[0087] FIG. 2 shows an embodiment of the syringe pump according to the present disclosure in a schematically simplified top view;

[0088] FIG. 3 shows the execution of an exemplary embodiment of the method according to the present disclosure in a flow diagram; and

[0089] FIG. 4 shows the execution of an exemplary embodiment of the method according to the present disclosure in a summary.

DETAILED DESCRIPTION

[0090] FIG. 1a and FIG. 1b show, each from the side, a conventional syringe 1, e.g. fillable with heparin, which may be a disposable syringe and/or a pre-filled syringe. FIG. 1a shows said syringe in an empty state, FIG. 1b shows it in a completely filled state or the state it takes when it is completely filled.

[0091] The syringe 1 comprises a syringe cylinder 2 and a plunger 5.

[0092] The syringe cylinder 2 comprises an optional luer cone 3 integrally formed on its head side and a syringe flange 4 formed on the opposite end.

[0093] The plunger 5 is usually made of elastomer material and is plug-shaped. It is positioned in the interior of the syringe cylinder 2 and is connected to a plunger rod 6 enabling it to be axially movable within the syringe cylinder 2.

[0094] The plunger 5 ends with a usually oval or round push plate 7 when viewed from the top. The push plate 7 is shown from the side in FIG. 1a and FIG. 1b.

[0095] In FIG. 1a, the plunger 5 is in a first end position B, in FIG. 1b in a second end position C. The plunger 5 arrives at or assumes the first end position B when the syringe content is completely emptied by moving the plunger 5. The plunger 5 arrives at the second end position C when the syringe 1 is filled to the maximum.

[0096] The shifting path of the plunger 5 within the syringe 1 is thus limited by both end positions B and C. The maximum displacement path to be maintained when the syringe 1 is used as intended is herein referred to as h.sub.max which is not to be exceeded in order to prevent the plunger 5 from being pulled out of the syringe cylinder 2 and the possible contamination risk associated therewith.

[0097] FIG. 2 shows an embodiment of a syringe pump 100 according to the present disclosure comprising a syringe receptacle with a syringe cavity 101. It further comprises a movable slide 103 having a toggle 105 being movable together with said slide 103, wherein the toggle 105 is fixed stationary or integrally relative to the slide or is a stationary or integral part thereof.

[0098] A motor 107 moves, e.g. via a spindle 109, the slide 103 in motor steps. The direction in which the travel or movement path of the slide 103 extends is indicated by double arrow.

[0099] The movement of the slide 103 comes leftwards (with regard to FIG. 2), i.e. towards the luer cone 3, to a halt or standstill latest when a first end stop A is reached, which is indicated by a dashed line.

[0100] The movement of the slide 103 comes rightwards (with regard to FIG. 2), i.e. towards the push plate 7, to a halt latest when a second end stop D is reached, which is likewise indicated by a dashed line.

[0101] The end stops A and D are to be understood as mechanical final stops of the slide 103: moving the slide over or beyond these points A and D is technically impossible, even when no syringe 1 is inserted in the syringe pump 100.

[0102] The end stops A and D are each outside the first and second end position B respectively C, described with regard to FIG. 1.

[0103] At the syringe receptacle, a first sensor 111 and a second sensor 113 are stationary connected to e.g. a housing of the syringe pump 100.

[0104] The slide 103 in turn may comprise a permanent magnet 115 which may serve to detect, in known manner, in interaction or alternation with the first sensor 111 and/or the second sensor 113, when the slide 103 reaches the position of the first sensor 111 or of the second sensor 113 or passes by. The first and the second sensor 111 or 113 are therefore configured as Hall sensors. Evaluation devices required for determining or evaluating the signals received from the Hall sensors are provided.

[0105] As an alternative to configuring the sensors 111 and 113 as Hall sensors, one or both sensors may be designed as light barriers, wherein combinations of a Hall sensor and a light barrier are likewise contemplated by the present disclosure.

[0106] Further contemplated by the present disclosure is that both sensors 111 and 113, or any one of them, being stationary with the slide 103, move together with the slide 103 when it is being moved. In such embodiments, the permanent magnet 115 may be positioned at the syringe receptacle.

[0107] The syringe pump 100 further comprises a counting device 120, a control device 130, a storage device 140 and an input device 150 or is respectively connected thereto in signal communication, as indicated in FIG. 2.

[0108] FIG. 2 shows the syringe pump 100 according to the present disclosure having a syringe 1 inserted therein. This shared or joint illustration serves for a better explanation of the interaction of the syringe pump 100 and the syringe 1 during the intended use of the syringe pump 100 or the syringe 1. It is however not required to insert the syringe 1 in the syringe pump 100 for calibrating.

[0109] For the experimental determination of the offset for the automatic calibration process, the reference syringe was previously inserted in several syringe pumps of the same type and the average value detected therefrom has been stored in the storage device. This process for determining the offset is not part of the intended use of the syringe pump. For calibration however, the offset according to step a) may be stored or entered or accordingly read out.

[0110] FIG. 3 shows the execution of an embodiment of the method according to the present disclosure in a flow diagram, wherein the steps denoted with S refer to steps of the syringe pump 100 relating to the slide and the steps denoted with Z refer to steps relating to the input device 150 (or by the latter), the counting device 120 or the storage device 140. The following applies:

[0111] Step Z1 is optional and relates to entering at least information about a particular type of the syringe 1 using the input device 150. The above offset may be included thereto.

[0112] Step Z2 is likewise optional and relates to reading out the information about a particular type of the syringe 1 (e.g. h.sub.max) stored in the storage device 140.

[0113] Step S1 relates to moving the toggle 105 by the slide 103 in a position between the first end position B and the second end position C, in particular in a position between the first sensor 111 and the second sensor 113, in case this position has not been already reached. This may take place in particular at a first speed. This may be between 100 s/microstep and 1000 s/microstep, preferably 500 s/microstep.

[0114] A microstep is a step size of the pump motor; the term may stand for a rotation measure or for a linear measure.

[0115] Step S2 relates to moving the toggle 105, particularly at a second speed, by the slide 103 such that the plunger with an inserted syringe would reach the first end position B or until a predetermined section of the slide 103, e.g. the permanent magnet 115 has reached the first end stop A. Said second speed may be between 1000 s/microstep and 10000 s/microstep, preferably 5000 s/microstep. Alternatively, the second speed may be between 1000 s/microstep and 2000 s/microstep, in particular 1400 s/microstep.

[0116] When the predetermined section of the slide 103, e.g. the permanent magnet 115, reaches or passes by the position of the second sensor 113 according to step Z3, the motor steps, upon or when reaching or passing by this position, are set or determined, e.g. by the counting device 120, as a first count value ZW1 and are stored as position of the second sensor 113. Optionally, the counting device 120 is reset to 0 afterwards.

[0117] In step S3 the toggle 105 is moved by the slide 103 further on towards the first end position B or the second end stop A.

[0118] Hence, in step Z4 when the plunger 5 reaches the first end position B or when the slide 103 reaches the first end stop A, a second count value ZW2 detected by the counting device 120 is determined. This may be stored as position of the end position B or as position of the end stop A.

[0119] Step Z5 relates to calculating, e.g. using the counting device 120 or another device programmed for this purpose, a calibration value K2 of the second sensor 113 based on both previous count values ZW1 and ZW2. This calibration value K2 for the second senor 113 is stored by the storage device 140.

[0120] Step Z6 is optional and relates to resetting the counting device 120, e.g. to 0.

[0121] In step S4 the toggle 105 is moved by the slide 103, in particular at the a.m. second speed or at a third speed, towards the second end position C. The third speed may be between 10000 s/microstep and 50000 s/microstep, preferably 20000 s/microstep.

[0122] Step Z7 relates to detecting or determining the position of the first sensor 111 by the counting device 120. Said position is determined starting from the first end position B or from the first end stop A until the predetermined section of the slide 103, e.g. the permanent magnet 115, reaches or passes by the position of the first sensor 111, by a third count value ZW3 which is optionally stored e.g. as position of the first sensor 111.

[0123] In step Z8 a calibration value K1 for the first sensor 111, is now determined for example based on the set value ZW3. In some embodiments this calibration value K1 may be calculated additionally with reference to the already set and stored lengths and/or positions. This calibration value K1 for the first sensor 111 is likewise stored by the storage device 140.

[0124] FIG. 4 shows the execution of an exemplary embodiment of the method according to the present disclosure in a summary.

[0125] The summary further illustrates the set count values ZW1, ZW2 and ZW3. Said values are each set or determined when the here exemplary permanent magnet 115 reaches and/or passes the sensor 111, 113 in the direction indicated by the respective arrow or when the first end position A is reached. These count values ZW1, ZW2 and ZW3 may be used for determining the calibration values K1 and K2, which specify the position of the Hall sensors relative to the first end stop A (or relative to the first end position B).

[0126] Alternatively, it is possible to set the counting device 120 to zero upon or when reaching the respective positions and thus to directly consider or accept the determined count values as calibration values.

LIST OF REFERENCE NUMERALS

[0127] 1 syringe [0128] 2 syringe cylinder [0129] 3 luer cone [0130] 4 syringe flange [0131] 5 plunger [0132] 6 plunger rod [0133] 7 press plate [0134] 100 syringe pump [0135] 101 syringe cavity [0136] 103 slide [0137] 105 toggle or pin [0138] 107 motor [0139] 109 spindle [0140] 111 first sensor [0141] 113 second sensor [0142] 115 permanent magnet [0143] 120 counting device [0144] 130 control device [0145] 140 storage device [0146] 150 input device [0147] A first end stop [0148] B first end position [0149] C second end position [0150] D second end stop [0151] Sx n.sup.th method step on the syringe pump side [0152] Zx n.sup.th method step on the side of the input device, storage device or counting device [0153] K1 calibration value of the first sensor 111 [0154] K2 calibration value of the second sensor 113 [0155] ZW1 first count value [0156] ZW2 second count value [0157] ZW3 third count value [0158] h.sub.max maximum displacement of the plunger or of the plunger rod inside the syringe cylinder when the syringe is used as intended; the maximum displacement is determined such that an undesirable pulling or withdrawal of the plunger out of the cylinder is avoided