Fluid dose, flow and coagulation sensor for medical instrument

• US 5,710,622 A
• Filed: 06/07/1995
• Issued: 01/20/1998
• Est. Priority Date: 08/31/1993
• Status: Expired due to Term

• Current Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Original Assignee: Boehringer Mannheim Corporation (Roche Holding AG)
• Inventors: Murphy, William J., Storvick, David E., Neel, Gary T., Young, Morris J., Parker, James R., Kennedy, Daniel L., Collins, Rick L., Thomeczek, Charles L. Jr., Lennert, George R.
• Primary Examiner(s): Nasser, Robert L.
• Application Number:
  US08/478,409
• Time in Patent Office: 958 Days
• Field of Search: 128/630, 128/632, 128/633, 128/634, 128/635, 128/653.1, 128/657, 128/664-7, 128/672, 128/677, 128/680-3, 128/687, 128/637, 73/53.01, 356/39-41
• US Class Current: 356/39
• CPC Class Codes: G01N 11/06 by timing the outflow of a known quantity
• CPC Class Codes: G01N 21/0303 Optical path conditioning in cuvettes, e.g. windows; adapted optical elements or systems; path modifying or adjustment G01N21/031 - G01N21/15 take precedence
• CPC Class Codes: G01N 21/0332 with temperature control control of temperature G05D23/00; cryostats F17C3/08
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: G01N 33/4905 Determining clotting time of blood by chemical methods G01N33/86, C12Q1/56
• CPC Class Codes: G01N 35/00594 Quality control, including calibration or testing of components of the analyser
• CPC Class Codes: G01N 35/00693 Calibration

Abstract

A method of immunizing the operation of an instrument which determines a characteristic of a biological fluid or a control against noise. The instrument includes a surface upon which a user deposits a sample of biological fluid or control the characteristic of which is to be determined. The instrument irradiates the sample and detects radiation from the sample to determine the characteristic. The method comprises monitoring the detected radiation a first time to determine if the detected radiation is increasing or decreasing, forming a first change in detected radiation from said first monitoring, subsequently monitoring the detected radiation a second time to determine if the detected radiation is increasing or decreasing, forming a second change in detected radiation from said second monitoring, forming an overall change in detected radiation from the first and second monitorings, establishing a first threshold, establishing a second threshold, comparing the first change to the first threshold, comparing the second change to the first threshold, if the magnitudes of both the first and second changes are greater than the first threshold, comparing the overall change in radiation to the second threshold, and determining the characteristic if the magnitudes of the first and second changes are greater than the first threshold and the overall change is greater than the second threshold.

Claims

1. A method of determining a characteristic of a biological fluid or a control using an instrument, the instrument including a surface upon which a user deposits a sample of biological fluid or control the characteristic of which is to be determined, the instrument irradiating the sample and detecting radiation from the sample to determine the characteristic, the method comprising the steps of monitoring the detected radiation a first time to determine if the detected radiation is increasing or decreasing, forming a first change in detected radiation from said first monitoring, subsequently monitoring the detected radiation a second time to determine if the detected radiation is increasing or decreasing, forming a second change in detected radiation from said second monitoring, forming an overall change in detected radiation from the first and second monitorings, establishing a first threshold, establishing a second threshold, comparing the first change to the first threshold, comparing the second change to the first threshold, if the magnitudes of both the first and second changes are greater than the first threshold, comparing the overall change in radiation to the second threshold, and determining the characteristic if the magnitudes of the first and second changes are greater than the first threshold and the overall change is greater than the second threshold.

2. The method of claim 1 further comprising the step of determining if the detected radiation is negative relative to a reference at the beginning of the first time, at the end of the first time, at the beginning of the second time, and at the end of the second time.

3. The method of claim 2 wherein the end of the first time is the beginning of the second time.

4. A method of immunizing the operation of an instrument which determines a characteristic of a biological fluid or a control using an instrument, the instrument including a surface upon which a user deposits a sample of biological fluid or control the characteristic of which is to be determined, the instrument irradiating the sample and detecting radiation from the sample to determine the characteristic, the method comprising the steps of establishing first, second and third thresholds, monitoring the detected radiation a first time to determine if the detected radiation is increasing or decreasing, forming a first change in detected radiation from said first monitoring if the magnitude of the detected radiation during the first time is greater than the first threshold, subsequently monitoring the detected radiation a second time to determine if the detected radiation is increasing or decreasing, forming a second change in detected radiation from said second monitoring if the magnitude of the detected radiation during the second time is greater than the first threshold, comparing the first and second changes to the second threshold if the magnitudes of the detected radiation during both the first and second times are greater than the first threshold, forming an overall change in detected radiation from the first and second monitorings, comparing the overall change to the third threshold if the magnitudes of the detected radiation during both the first and second times are greater than the first threshold and the magnitudes of both the first and second changes are greater than the second threshold, and determining the characteristic if the magnitudes of the detected radiation during the first and second times are greater than the first threshold, the magnitudes of the first and second changes are greater than the second threshold, and the overall change is greater than the third threshold.