QUALITY ASSURANCE SYSTEM AND METHOD FOR POINT-OF-CARE TESTING

• US 20090119047A1
• Filed: 09/15/2008
• Published: 05/07/2009
• Est. Priority Date: 09/13/2007
• Status: Active Grant

• Current Assignee: Abbott Point Of Care Incorporated (Abbott Laboratories)
• Original Assignee: i STAT Corporation (Abbott Laboratories)
• Inventors: BROUWER, Eric, BREEZE, Steven, ZELIN, Michael P.
• Granted Patent: US 8,510,067 B2
• Time in Patent Office: Days
• US Class Current: 702/82
• CPC Class Codes: G01K 3/04 in respect of time
• CPC Class Codes: G01N 2035/00089 Magazines
• CPC Class Codes: G01N 27/3274 Corrective measures, e.g. error detection, compensation for temperature or hematocrit, calibration coding of calibration information G01N33/48771
• CPC Class Codes: G01N 27/4163 checking the operation of, or calibrating, the measuring apparatus G01N27/3274, G01N27/4175 and G01N33/0006 take precedence
• CPC Class Codes: G01N 31/229 for investigating time/temperature history

Abstract

An improved quality assurance system and method for point-of-care testing are disclosed. The present invention provides quality assurance for laboratory quality tests performed by a blood analysis system or the like at the point of patient care without the need for running liquid-based quality control materials on the analysis system. Quality assurance of a quantitative physiological sample test system is performed without using a quality control sample by monitoring the thermal and temporal stress of a component used with the test system. Alert information is generated that indicates that the component has failed quality assurance when the thermal and temporal stress exceeds a predetermined thermal-temporal stress threshold. Alternatively, the present invention provides quality assurance for laboratory quality tests performed by a blood analysis system or the like at the point of patient care by minimizing the need for running liquid-based quality control materials on the analysis system.

Claims

1. A system for performing quality assurance of a quantitative physiological sample test system without using a quality control sample, comprising:

a thermal and temporal stress monitor module,

wherein the thermal and temporal stress monitor module is configured to monitor thermal and temporal stress of a component used with the test system; and

a quality assurance failure alert module in communication with the thermal and temporal stress monitor module,

wherein the quality assurance failure alert module is configured to generate alert information indicating that the component has failed quality assurance when the thermal and temporal stress exceeds a predetermined thermal-temporal stress threshold.

2. The system of claim 1, wherein the physiological sample comprises one of blood, plasma, serum, saliva, urine, cerebrospinal fluid, and amended forms thereof.

3. The system of claim 1, wherein the quality control sample comprises a liquid control.

4. The system of claim 1, wherein the component is used with the test system when the thermal and temporal stress does not exceed the predetermined thermal-temporal stress threshold.

5. The system of claim 1, wherein the thermal and temporal stress monitor module is separate from the test system and in a substantially same thermal environment as the test system.

6. The system of claim 1, wherein the thermal and temporal stress monitor module is integrated with the test system.

7. The system of claim 1, wherein the thermal and temporal stress monitor module is configured to monitor a temperature-time indicator associated with the component.

8. The system of claim 1, wherein the thermal and temporal stress monitor module comprises at least one of an electrically conductive wax, a temperature-dependent liquid crystal, a shift in baseline calibration potential of a potentiometric sensor, a liposomal release of an enzyme inhibitor, a liposomal release of an electrically conductive liquid, a liposomal release of an elevated ion concentration, a liposomal release of a molecule or ion capable of electrochemical detection, a thermistor, a thermocouple, a thermal ink, a temperature-dependent chemical reaction, a temperature-dependent color changing patch, and a temperature-dependent phase change of a material.

9. The system of claim 1, wherein the component comprises a sample testing cartridge.

10. The system of claim 1, wherein the test system comprises a blood analysis system.

11. The system of claim 10, wherein the blood analysis system comprises a portable component reader.

12. The system of claim 1, wherein the component comprises a blood testing cartridge.

13. The system of claim 12, wherein the blood testing cartridge comprises a single-use blood testing cartridge.

14. The system of claim 12, wherein the blood testing cartridge includes at least one electrochemical sensor.

15. The system of claim 1, wherein the component comprises a sensor.

16. The system of claim 15, wherein the sensor comprises one of an electrochemical sensor, an optical sensor, a luminescence sensor, a fluorescence sensor, an amperometric sensor, a potentiometric sensor, a conductimetric sensor, a wave guide, an evanescence sensor, a biosensor, a surface plasmon resonance sensor, an acoustic wave sensor, and a reflectance sensor.

17. The system of claim 1, wherein the component is stored in a refrigerated enclosure below a predetermined temperature.

18. The system of claim 17, wherein the component is removed from the refrigerated enclosure prior to use with the test system, and

wherein the component is allowed to attain ambient temperature prior to being used with the test system.

19. The system of claim 1, wherein the test system is configured to perform a test to determine an analyte.

20. The system of claim 19, wherein the analyte comprises one of sodium, potassium, chloride, calcium, glucose, lactate, creatinine, urea, hematocrit, prothrombin time, activated clotting time, activated partial thromboplastin time, troponin I, troponin T, creatine kinase MB, brain natriuretic peptide, NTproBNP, C-reactive protein, pO2, PCO2, and pH.

21. The system of claim 1, wherein the component is associated with a batch of substantially similar components, and

wherein the quality assurance failure alert module is configured to generate alert information indicating that the batch has failed quality assurance when the thermal and temporal stress of the component exceeds the predetermined thermal-temporal stress threshold.

22. The system of claim 1, wherein the test system is configured to perform at least one failsafe check prior to use of the component.

23. The system of claim 22, wherein the failsafe check comprises at least one of verification that an ambient temperature is within a predetermined range, verification that the component is not faulty, and verification that the test system is not faulty.

24. The system of claim 23, wherein the verification that the test system is not faulty comprises at least one of testing electrical integrity of an electrical connector associated with the test system, and testing operational integrity of operational amplifiers associated with the test system.

25. The system of claim 1, wherein the test system comprises:

an electronic simulator,

wherein the electronic simulator is configured to simulate signals produced by the component.

26. The system of claim 25, wherein the electronic simulator is configured to generate simulation signals for testing at least one of electrical integrity of an electrical connector associated with the test system and operational integrity of operational amplifiers associated with the test system.

27. The system of claim 1, wherein the test system comprises:

a display module,

wherein the display module is configured to display alerts in accordance with the alert information.

28. The system of claim 27, wherein the test system is configured to suppress display of test results when the component has failed quality assurance.

29. The system of claim 1, wherein the system comprises:

a log module in communication with the quality assurance failure alert module,

wherein the log module is configured to maintain a log of the thermal and temporal stress of a plurality of components.

30. The system of claim 1, wherein the predetermined thermal-temporal stress threshold is generated in accordance with a total allowable error of the test system.

31. The system of claim 1, wherein the predetermined thermal-temporal stress threshold comprises a plurality of combinations of thermal stress and temporal stress.

32. The system of claim 1, wherein the predetermined thermal-temporal stress threshold comprises a predetermined temperature-time profile.

33. A system for evaluating thermal and temporal stress quality assurance of a quantitative electrochemical physiological sample test system, comprising:

a first electrochemical sensor; and

a second electrochemical sensor,

wherein the first and second electrochemical sensors are contacted with a calibrant fluid,

wherein the first electrochemical sensor is configured to determine a first calibration voltage associated with the concentration of a first analyte in the calibrant fluid in accordance with a first check threshold,

wherein the second electrochemical sensor is configured to determine a second calibration voltage associated with the concentration of a second analyte in the calibrant fluid in accordance with a second check threshold, and

wherein the test system is disqualified from performing a physiological sample test when both the first and second check thresholds are exceeded.

34. The system of claim 33, where the first electrochemical sensor comprises a sodium ion-selective electrode, and

wherein the second electrochemical sensor comprises a calcium ion-selective electrode.

35. A system for thermal and temporal stress quality assurance of a quantitative electrochemical physiological sample test system, comprising:

a plurality of electrochemical sensors,

wherein the plurality of electrochemical sensors are contacted with a calibrant fluid; and

a calibration circuit in communication with the plurality of electrochemical sensors,

wherein the calibration circuit is configured to determine a calibration parameter associated with a concentration of an analyte in the calibrant fluid for each electrochemical sensor of a subset of the plurality of electrochemical sensors in accordance with a predetermined check threshold, and

wherein the calibration circuit is configured to disqualify the test system from performing a physiological sample test when the predetermined check threshold is exceeded for each electrochemical sensor of the subset.

36. The system of claim 35, wherein the subset of electrochemical sensors comprises a calcium ion-selective electrode and a BUN electrode.

37. The system of claim 35, wherein the subset of electrochemical sensors comprises a sodium ion-selective electrode, a calcium ion-selective electrode, and a BUN electrode.

38. The system of claim 35, wherein the calibration parameter comprises a calibration voltage.

39. The system of claim 35, wherein the calibration parameter comprises a calibration voltage drift rate.

40. The system of claim 35, wherein the calibration parameter comprises a combination of a calibration voltage and a calibration voltage drift rate.

41. The system of claim 35, wherein each of the plurality of electrochemical sensors comprises one of a sodium sensor, a potassium sensor, a chloride sensor, a pH sensor, a pO2 sensor, a pCO2 sensor, a lactate sensor, a glucose sensor, a creatinine sensor, a BUN electrode, a calcium sensor, a magnesium sensor, and a hematocrit sensor.

42. A method of quality assurance of a quantitative physiological sample test system performed without running a quality control sample, comprising the steps of:

a.) monitoring thermal and temporal stress of a component used with the test system; and

b.) generating alert information indicating that the component has failed quality assurance when the thermal and temporal stress exceeds a predetermined thermal-temporal stress threshold.

43. The method of claim 42, wherein the predetermined thermal-temporal stress threshold is generated in accordance with a total allowable error of the test system.

44. The method of claim 42, wherein the predetermined thermal-temporal stress threshold comprises a plurality of combinations of temperature and time.

45. The method of claim 42, wherein the component is used with the test system when the thermal and temporal stress do not exceed the predetermined thermal-temporal stress threshold.

46. The method of claim 42, wherein step (a) is performed using at least one of an electrically conductive wax, a temperature-dependent liquid crystal, a shift in baseline calibration potential of a potentiometric sensor, a liposomal release of an enzyme inhibitor, a liposomal release of an electrically conductive liquid, a liposomal release of an elevated ion concentration, a liposomal release of a molecule or ion capable of electrochemical detection, a thermistor, a thermocouple, a thermal ink, a temperature-dependent chemical reaction, a temperature-dependent color changing patch, and a temperature-dependent phase change of a material.

47. The method of claim 42, wherein steps (a) and (b) are performed at one of a hospital central laboratory, a satellite laboratory, a point-of-care location, a patient bedside, a moving vehicle, and a laboratory services vendor.

48. The method of claim 42, wherein the test system comprises a blood analysis system.

49. The method of claim 48, wherein the blood analysis system comprises a portable component reader.

50. The method of claim 42, wherein the component comprises a blood testing cartridge.

51. The method of claim 50, wherein the blood testing cartridge comprises a single-use blood testing cartridge.

52. The method of claim 50, wherein the blood testing cartridge comprises at least one electrochemical sensor.

53. The method of claim 42, wherein the physiological sample comprises one of blood, plasma, serum, saliva, urine, cerebrospinal fluid, and amended forms thereof.

54. The method of claim 42, comprising the step of:

c.) storing the component in a refrigerated enclosure below a predetermined temperature.

55. The method of claim 42, comprising the steps of:

c.) storing the component in a refrigerator below a predetermined temperature;

d.) removing the component from the refrigerator prior to use with the test system; and

e.) allowing the component to attain room temperature prior to being used to perform a test.

56. The method of claim 42, wherein the quality control sample comprises a liquid control.

57. The method of claim 42, wherein the component comprises a sensor.

58. The method of claim 57, wherein the sensor comprises one of an electrochemical sensor, an optical sensor, a luminescence sensor, a fluorescence sensor, an amperometric sensor, a potentiometric sensor, a conductimetric sensor, a wave guide, an evanescence sensor, a biosensor, a surface plasmon resonance sensor, an acoustic wave sensor, and a reflectance sensor.

59. The method of claim 42, wherein the test system performs a test to determine an analyte.

60. The method of claim 59, wherein the analyte comprises one of sodium, potassium, chloride, calcium, glucose, lactate, creatinine, urea, hematocrit, prothrombin time, activated clotting time, activated partial thromboplastin time, troponin I, troponin T, creatine kinase MB, brain natriuretic peptide, NTproBNP, C-reactive protein, pO2, PCO2, and pH.

61. The method of claim 42, wherein the component is associated with a batch of substantially similar components, and

wherein the method comprises the step of:

c.) generating alert information indicating that the batch has failed quality assurance when the thermal and temporal stress of the component exceeds the predetermined thermal-temporal stress threshold.

62. The method of claim 42, wherein the test system performs at least one failsafe check prior to use of the component.

63. The method of claim 62, wherein for the failsafe check the test system performs at least one of the steps of i.) verifying that an ambient temperature is within a predetermined range, ii.) verifying that the component is not faulty, and iii.) verifying that the test system is not faulty.

64. The method of claim 63, wherein for step (iii) the test system performs at least one of the steps of 1.) testing electrical integrity of an electrical connector associated with the test system, and 2.) testing operational integrity of operational amplifiers associated with the test system.

65. The method of claim 42, comprising the step of:

c.) simulating signals produced by the component.

66. The method of claim 65, wherein step (c) comprises at least one of the steps of:

d.) generating simulation signals for testing electrical integrity of an electrical connector associated with the test system; and

e.) generating simulation signals for testing operational integrity of operational amplifiers associated with the test system.

67. The method of claim 42, comprising the step of:

d.) displaying alerts in accordance with the alert information.

68. The method of claim 42, comprising the steps of:

d.) suppressing display of test results when the component has failed quality assurance.

69. The method of claim 42, comprising the step of:

c.) maintaining a log of the thermal and temporal stress of a plurality of components.

70. A method of quality assurance of a quantitative blood sample testing system not requiring running one or more liquid quality control samples, the testing system comprising a point-of-care test reader and a plurality of single-use test devices for performing one or more tests, and wherein each of the tests is performed to a precision of better than about 10%, wherein the method comprises the steps of:

a.) monitoring at least one of the plurality of single-use test devices in accordance with thermal and temporal stress and a predetermined thermal-temporal stress threshold; and

b.) selecting the single-use test devices for testing a blood sample with the point-of-care test reader for which the associated thermal and temporal stress has not exceeded the predetermined thermal-temporal stress threshold.

71. A method of quality assurance of a quantitative blood sample testing system not requiring running a liquid quality control sample or a set of quality control samples, the testing system comprising a re-usable portable reader and a plurality of single-use test devices for performing a selected menu of one or more tests, wherein each of the tests is performed to a precision of better than about 10%, wherein the method comprises the steps of:

a.) determining exposure of each of the single-use test devices to temporal and thermal stress in accordance with a predetermined time-temperature stress threshold by interrogating a time-temperature indicator associated with each single-use test device; and

b.) reporting blood test results for single-use test devices that have not exceeded the time-temperature stress threshold.

72. A method of quality assurance of a quantitative blood sample testing system used for point-of-care testing, the testing system comprising a re-usable portable reader and a single-use test device for performing one or more tests for analytes in the blood sample, wherein each analyte test is performed to a precision of better than about 10%, wherein the method comprises the steps of:

a.) determining exposure of a batch of the single-use test devices to thermal and temporal stress by testing a single test device from the batch with a single control fluid containing a predetermined concentration of at least one analyte in the sample,

wherein the analyte is selected to provide a test result indicative of thermal and temporal stress greater than a predetermined threshold of a total allowable error for the test; and

b.) indicating that the batch of test devices is unsuitable for use in blood sample testing when the test result is greater than the predetermined threshold.

73. The method of claim 72, wherein the one or more tests comprise determination of an analyte, and

wherein the analyte comprises at least one of sodium, potassium, chloride, calcium, glucose, lactate, creatinine, urea, hematocrit, prothrombin time, activated clotting time, activated partial thromboplastin time, troponin I, troponin T, creatine kinase MB, brain natriuretic peptide, NTproBNP, C-reactive protein, pO2, PCO2 and pH.

74. The method of claim 72, wherein the test result indicative of thermal and temporal stress comprises at least one of calcium, creatinine, and urea.

75. The method of claim 72, wherein the single quality control fluid comprises a known amount of at least one test analyte for a test that is indicative of thermal and temporal stress of a sub-system.

76. The method of claim 75, wherein the test analyte is comprises at least one of calcium, creatinine and urea.

77. A method of quality assurance of a quantitative sample testing system, the sample testing system including a re-usable reader and a single-use test device, wherein each test is performed to a precision of better than about 10%, and wherein the method comprises the steps of:

a.) automatically determining a probable exposure of a batch of the single-use test devices with respect to thermal and temporal stress,

wherein a single device from the batch is tested with a single control fluid containing a predetermined concentration of at least one analyte in the sample,

wherein the analyte is selected to provide a test result indicative of thermal and temporal stress beyond a predetermined threshold of a total allowable error for the test; and

b.) reporting the batch of single-use test devices is unsuitable for use in blood sample testing when the test result is beyond the predetermined threshold.

78. A method of characterizing a manufacturing lot of single-use test devices with respect to end-user quality assurance, wherein the single-use test devices are configured to perform one or more tests to a precision of better than about 10%, wherein the method comprises the steps of:

a.) determining the performance of a first portion of the lot in the absence of thermal and temporal stress with respect to an allowable total error for each test;

b.) applying thermal and temporal stresses to one or more other portions of the lot;

c.) determining performance of each portion with respect to the allowable total error for each test;

d.) determining differences in performance between the first and other portions; and

e.) determining a thermal and temporal stress threshold for use by a reader capable of using the lot of single-use test devices to determine whether the single-use test devices have been exposed to a thermal and temporal stress beyond a predetermined threshold.

79. A method of thermal stress quality assurance of a quantitative electrochemical physiological sample test system, comprising the steps of:

a.) contacting first and second electrochemical sensors with a calibrant fluid;

b.) determining a first calibration voltage associated with a concentration of a first analyte in the calibrant fluid in accordance with a first thermal check threshold;

c.) determining a second calibration voltage associated with the concentration of a second analyte in the calibrant fluid in accordance with a second thermal check threshold; and

d.) disqualifying the test system from performing a physiological sample test when both the first and second thermal check thresholds are exceeded.

80. The method of claim 79, wherein the first electrochemical sensor comprises a sodium ion-selective electrode, and

wherein the second electrochemical sensor comprises a calcium ion-selective electrode.

81. A method of thermal stress quality assurance of a quantitative electrochemical physiological sample test system, comprising the steps of:

a.) contacting a plurality of electrochemical sensors with a calibrant fluid;

b.) determining a calibration parameter associated with a concentration of an analyte in the calibrant fluid for each electrochemical sensor of a subset of the plurality of electrochemical sensors in accordance with a predetermined thermal check threshold; and

c.) disqualifying the test system from performing a physiological sample test when the predetermined thermal check threshold is exceeded for each electrochemical sensor of the subset.

82. The method of claim 81, wherein the subset of electrochemical sensors comprises a calcium ion-selective electrode and a BUN electrode.

83. The method of claim 81, wherein the subset of electrochemical sensors comprises a sodium ion-selective electrode, a calcium ion-selective electrode, and a BUN electrode.

84. The method of claim 81, wherein the calibration parameter comprises a calibration voltage.

85. The method of claim 81, wherein the calibration parameter comprises a calibration voltage drift rate.

86. The method of claim 81, wherein the calibration parameter comprises a combination of a calibration voltage and a calibration voltage drift rate.

87. The method of claim 81, wherein each of the plurality of electrochemical sensors comprises one of a sodium sensor, a potassium sensor, a chloride sensor, a pH sensor, a pO2 sensor, a pCO2 sensor, a lactate sensor, a glucose sensor, a creatinine sensor, a BUN electrode, a calcium sensor, a magnesium sensor, and a hematocrit sensor.

88. A method of quality assurance of a quantitative physiological sample test system performed without running a quality control sample, comprising the steps of:

a.) monitoring thermal and temporal stress of a component of the test system; and

b.) determining suitability of using the component with the test system to perform the physiological sample test in accordance with the thermal and temporal stress of the component and a predetermined thermal-temporal stress threshold.

89. A system for performing quality assurance of a quantitative physiological sample test system without using a quality control sample, comprising:

a thermal and temporal stress monitor module,

wherein the thermal and temporal stress monitor module is configured to monitor thermal and temporal stress of a component used with the test system, and

wherein the component is associated with a batch of substantially similar components; and

a quality assurance failure alert module in communication with the thermal and temporal stress monitor module,

wherein the quality assurance failure alert module is configured to generate alert information indicating that the batch has failed quality assurance when the thermal and temporal stress of the component exceeds a predetermined thermal-temporal stress threshold.

90. A method of quality assurance of a quantitative physiological sample test system performed without running a quality control sample, comprising the steps of:

a.) monitoring thermal and temporal stress of a component used with the test system,

wherein the component is associated with a batch of substantially similar components; and

b.) generating alert information indicating that the batch has failed quality assurance when the thermal and temporal stress of the component exceeds a predetermined thermal-temporal stress threshold.

91. A system for performing quality assurance of a quantitative physiological sample test system without using a quality control sample, comprising:

a thermal stress monitor module,

wherein the thermal stress monitor module is configured to monitor thermal stress of a component used with the test system;

a temporal stress monitor module in communication with the thermal stress monitor module,

wherein the temporal stress monitor module is configured to monitor temporal stress of the component used with the test system; and

a quality assurance failure alert module in communication with the thermal stress monitor module and the temporal stress monitor module,

wherein the quality assurance failure alert module is configured to generate alert information that the component has failed quality assurance when the thermal and temporal stress exceed a predetermined thermal-temporal stress threshold.