Enhanced monitoring device for surgical gloves and other barriers

• US 5,389,097 A
• Filed: 06/22/1994
• Issued: 02/14/1995
• Est. Priority Date: 05/25/1990
• Status: Expired due to Fees

• Current Assignee: William H. Marshall
• Original Assignee: Novatec Medical Products, Inc.
• Inventors: Maxham, Mark, Williams, Robert E., Bennett, John K., Marshall, William H.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US08/277,984
• Time in Patent Office: 237 Days
• Field of Search: 606/32, 606/34, 340/540
• US Class Current: 606/34
• CPC Class Codes: A61B 42/30 Devices for detecting perforations, leaks or tears
• CPC Class Codes: G01M 3/187 for flexible or elastic containers
• CPC Class Codes: G01M 3/40 by using electric means, e.g. by observing electric discharges

Abstract

A monitoring device for detecting adulteration of an article used in critical use applications such as a surgical glove where the gloves are worn by the surgeon and are exposed to the body fluids of a patient. The device includes the detection of a particular value of electrical condition, preferably resistance or impedance, as well as the first and second derivatives of electrical condition. These values are monitored in a substantially continuous manner and are smoothed and filtered to determine when a hole or thin spot in the glove occurs. In addition, the device includes an autoranging function which maintains the measured voltage in a prescribed range, thus allowing the device to operate at a higher level of accuracy for a greater period of time than a device without the feature. Also, the device warns the health care professional when the electrical properties of the gloves have degraded to a point where the device may no longer reliably detect holes in the gloves.

Claims

1. Apparatus for detecting adulteration of an article that is used as a barrier to prevent transmission of disease or other dangerous fluid between first and second persons, comprising:

an electronic circuit including a current source, first and second leads coupled to said current source for electrical attachment to the first and second persons, a detection circuit means coupled to said first and second leads, and an alarm coupled to said detection circuit means to alert either the first or second person of a condition of adulteration of the article;

said current source providing a current to said first and second leads such that a series connection is made comprising the first person, the article, and the second person such that said article has an electrical condition;

said detection circuit means monitoring the rate of the rate of change of the electrical condition of the article for detecting adulteration of the article and generating a signal indicative thereof; and

said alarm receiving said adulteration indicating signal for providing an alarm when said detection circuit means detects a condition of adulteration of the article.

2. The apparatus of claim 1, wherein said detection circuit means further monitors the electrical condition and the rate of change of the electrical condition of the article in detecting adulteration and/or near-adulteration of the article.

3. The apparatus of claims 1 or 2, wherein the electrical condition monitored by said detection circuit means is resistance.

4. The apparatus of claims 1 or 2, wherein said current provided by said current source is a time-varying current;

and

wherein the electrical condition monitored by said detection circuit means is impedance.

5. The apparatus of claims 1 or 2, wherein said current is at a microamperage level.

6. The apparatus of claim 2, wherein said electrical condition includes voltage and current;

and

said detection circuit means periodically measures the voltage across the article and uses said voltage and the amount of said current to compute values representing the electrical condition of the article.

7. The apparatus of claim 6, wherein said detection circuit means periodically adjusts said current according to said measured voltage to maintain said voltage in a prescribed range.

8. The apparatus of claim 6, wherein said detection circuit means periodically calculates values for the rate of change and the rate of the rate of change of the electrical condition using said electrical condition values.

9. The apparatus of claim 8, wherein said detection circuit means stores an initial electrical condition value before a subsequent electrical condition value is computed and calculates a value for an initial rate of change of electrical condition by subtracting said subsequent electrical condition value from said initial electrical condition value.

10. The apparatus of claim 9, wherein said detection circuit means stores said initial value of the rate of change of the electrical condition before a subsequent value for the rate of change of the electrical condition is computed and calculates a value for the rate of the rate of change of the electrical condition by subtracting said subsequent value for the rate of change of the electrical condition value from said initial value for the rate of change of the electrical condition.

11. The apparatus of claim 10, wherein said detection circuit means arms if said electrical condition value is less than a first value and if either said value for the rate of change of the electrical condition is greater than a second value or said value for the rate of the rate of change of the electrical condition is greater than a third value.

12. The apparatus of claim 11, wherein means are provided for programming said second and third values to a level of protection.

13. The apparatus of claim 11, wherein said detection circuit means asserts said indicating signal if said detection circuit means is armed and a subsequent electrical condition value drops below a fourth value during a preset period of time.

14. The apparatus of claim 11, wherein said detection circuit means unarms after a period of time if during said period of time no electrical condition values have dropped below a fourth value.

15. The apparatus of claim 11, wherein said detection circuit means executes smoothing and/or filtering function or functions on a plurality of said computed electrical condition values, and wherein said detection circuit means uses said filtered electrical condition values in detecting a condition of adulteration or near adulteration of the article.

16. A method for detecting adulteration of an article which is used as a barrier to prevent transmission of disease between first and second persons, comprising the steps of:

providing current through a circuit comprised of the first person, the article, and the second person;

detecting an electrical condition, the rate of change of electrical condition, and the rate of the rate of change of electrical condition of the article; and

providing an alarm in response to a predesignated change in one or more of the electrical condition, the rate of change of electrical condition, or the rate of the rate of change of electrical condition of the article such that a condition of adulteration of the article is detected.

17. The method of claim 16, wherein the electrical condition monitored in said step of detecting is resistance.

18. The apparatus of claim 16, wherein said provided current is a time-varying current;

and

wherein the electrical condition monitored in said step of detecting is impedance.

19. The method of claim 16, wherein:

said electrical condition includes voltage and current; and

said step of detecting includes periodically measuring the voltage across the article and using said voltage and the amount of said provided current to compute values representing the electrical condition of the article.

20. The method of claim 19, wherein said step of detecting further includes periodically adjusting said provided current according to said measured voltage to maintain said voltage in a prescribed range in spite of deterioration of the electrical condition of said article with time.

21. The method of claim 19, wherein said step of detecting includes periodically calculating values for the rate of change and the rate of the rate of change of the electrical condition using said electrical condition values.

22. The method of claim 21, wherein said step of detecting includes arming of said alarm if said electrical condition value is less than a first value and if either said value for the rate of change of the electrical condition is greater than a second value or said value for the rate of the rate of change of the electrical condition is greater than a third value.

23. The method of claim 22, wherein:

said second and third values are programmed based on desired level of protection.

24. The method of claim 22, wherein said step of alarm providing is performed if said step of detecting has armed said alarm and a subsequent electrical condition value drops below a fourth value during a preset period of time.

25. The method of claim 22, wherein said step of detecting includes unarming after a preset period of time if during a preset period of time no electrical condition values have dropped below a fourth value.

26. The method of claim 22, said step of detecting includes further executing smoothing and/or filtering function or functions on a plurality of said computed electrical condition values to produce filtered electrical condition values;

wherein said filtered electrical condition values are used to detect a condition of adulteration of the article.

27. A method for detecting adulteration of an article that is used as a barrier to prevent transmission of disease between persons, comprising the steps of:

providing current through a circuit comprised of a first lead, the article, and a second lead to produce an electrical condition across said article;

detecting the electrical condition, the rate of change of electrical condition, and the rate of the rate of change of electrical condition of the article; and

providing an alarm in response to a predesignated change in one or more of the electrical condition, the rate of change of electrical condition, or the rate of the rate of change of electrical condition of the article such that a condition of adulteration of the article is detected.

28. Apparatus for detecting adulteration of a glove used in critical use applications where gloves are worn by a health care worker who is exposed to the body fluids of a patient, comprising:

an electronic circuit including a current source, first and second leads coupled to the current source for electrical attachment to the health care worker and to the patient, detection circuit means coupled to said first and second leads, and an alarm coupled to said detection circuit means to alert the health care worker of a condition of adulteration of a glove;

said current source providing a current to said first and second leads such that a series connection is made comprising said first lead, the health care worker, said gloves, and the patient to create an electrical condition across said gloves;

said detection circuit means monitoring the electrical condition, the rate of change of the electrical condition, and the rate of the rate of change of the electrical condition of a glove for detecting adulteration and/or near-adulteration of a glove and generating a signal indicative thereof; and

said alarm receiving said adulteration signal for providing an alarm when said detection circuit means detects a condition of adulteration of a glove.

29. Apparatus for detecting adulteration of a glove used in critical use applications where gloves are worn by a health care worker who may be exposed to the body fluids of a patient, comprising:

an electronic circuit including a current source, first and second leads coupled to said current source for electrical attachment to the health care worker and to the patient, detection circuit means coupled to said first and second leads, and an alarm coupled to said detection circuit means to alert the health care worker of a condition of adulteration of a glove;

said current source providing a current to said first and second leads such that a series connection is made comprising said first lead, the health care worker, said gloves, and the patient;

said detection circuit means monitoring the rate of the rate of change of the electrical condition of the gloves for detecting adulteration of a glove and generating a signal indicative thereof; and

said alarm receiving said indicating signal for providing an alarm when said detection circuit means detects a condition of adulteration of a glove.

30. The apparatus of claim 29, wherein said detection circuit means further monitors the electrical condition and the rate of change of the electrical condition of the gloves in detecting adulteration of a glove.

31. The structure set forth in claim 29, wherein:

a signal is provided at regular intervals to provide a periodic sign of proper operation.

32. Apparatus for detecting adulteration of an article which is used as a barrier to prevent transmission of disease between first and second persons, comprising:

an electronic circuit including a current source, first and second leads coupled to said current source for electrical attachment to the first and second persons, a detection circuit means coupled to aid first and second leads, and an alarm coupled to said detection circuit means to alert either the first or second person of a condition of adulteration of the article;

said current source providing a voltage and current to said first and second leads such that a series connection is made comprising the first person, the article, and the second person;

said detection circuit means periodically measuring said voltage across the article and using said voltage and the amount of said current to compute values representing an electrical condition of the article;

wherein the electrical condition monitored by said detection circuit means is resistance;

OR

wherein said current provided by said current source is a time-varying current and the electrical condition monitored by said detection circuit means is impedance;

said detection circuit means periodically adjusting said current according to said measured voltage to maintain said voltage in a prescribed range in spite of said barrier losing electrical characteristics with time;

said detection circuit means executing a smoothing function on a plurality of said computed electrical condition values to produce smoothed electrical condition values;

said detection circuit means periodically calculating values for the rate of change and the rate of the rate of change of the electrical condition using said smoothed electrical condition values;

said detection circuit means storing an initial electrical condition value before a subsequent electrical condition value is computed and calculating a value for the initial rate of change of the electrical condition by subtracting said subsequent electrical condition value from said initial electrical condition value;

said detection circuit means storing the initial value of the rate of change of the electrical condition when a subsequent value for the rate of change of the electrical condition is computed and calculating a value for the rate of the rate of change of the electrical condition by subtracting said subsequent value for the rate of change of the electrical condition value from said initial value for the rate of change of the electrical condition;

said detection circuit means arming if said electrical condition value is less than a first value and if either said value for the initial rate of change of the electrical condition is greater than a second value or said value for the rate of the rate of change of the electrical condition is greater than a third value;

wherein said second and third values are programmable based on perceived risk;

said detection circuit means unarming after a preset period of time if during said preset period of time no electrical condition values have dropped below a fourth value;

said detection circuit means asserting said indicating signal if said detection circuit means is armed and a subsequent electrical condition value drops below said fourth value during a preset period of time;

said alarm receiving said indicating signal for providing an alarm when said detection circuit means detects a condition of adulteration of the article.