OPTICAL IMAGING SYSTEM FOR AIR BUBBLE AND EMPTY BAG DETECTION IN AN INFUSION TUBE

• US 20130201471A1
• Filed: 03/14/2013
• Published: 08/08/2013
• Est. Priority Date: 10/19/2010
• Status: Active Grant

• Current Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Original Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Inventors: Bui, Tuan, Munro, James F.
• Granted Patent: US 9,128,051 B2
• Time in Patent Office: Days
• US Class Current: 356/73
• CPC Class Codes: G01N 21/59 Transmissivity G01N21/25 takes precedence

Abstract

An optical imaging system for use with an infusion tube having a drip chamber and an output tube. The drip chamber includes a first portion with a drip tube, a second portion with an exit port, and a third portion between the first and second portions. The optical imaging system includes: an illumination system with at least one light source for emitting light, an optical system, and a memory element storing computer executable instructions. The optical system receives the light transmitted by the output tube or the second portion and transmits data characterizing the received light. The system includes at least one processor configured to execute the computer executable instructions to: detect, using the data, an air bubble in the output tube or the second portion; and determine a volume of the detected air bubble.

Claims

1. An optical imaging system for use with an infusion tube having a drip chamber and an output tube, wherein the drip chamber includes a first portion with a drip tube, a second portion with an exit port, and a third portion located between the first and second portions, the optical imaging system comprising:

an illumination system with at least one light source for emitting first light;

an optical system for;

receiving the first light transmitted by the output tube or the second portion; and

,

transmitting first data characterizing the received first light;

a memory element configured to store computer executable instructions; and

,

at least one processor configured to execute the computer executable instructions to;

detect, using the first data, an air bubble in the output tube or the second portion; and

,

determine a volume of the detected air bubble.

2. The optical imaging system of claim 1, wherein the at least one processor configured to execute the computer executable instructions to:

compare the volume to a threshold value; and

,

for a volume exceeding the threshold value, generate and transmit an air alarm signal.

3. The optical imaging system of claim 1, wherein:

detecting an air bubble in the output tube or the second portion includes detecting, during a predetermined time period, a plurality of air bubbles sequentially passing through the output tube or the second portion;

determining a volume of the detected air bubble includes determining a respective volume for each air bubble in the plurality of air bubbles as said each air bubble is detected; and

,

determining a volume of the detected air bubble includes calculating a running total of the respective volumes as the respective volumes are determined.

4. The optical imaging system of claim 3, wherein the at least one processor configured to execute the computer executable instructions to:

determine that the respective volume for a last air bubble passing in sequence through the output tube or the second portion increases the running total beyond a predetermined maximum value; and

,

generate and transmit an air alarm signal.

5. The optical imaging system of claim 3, wherein the at least one processor configured to execute the computer executable instructions to:

compare the running total to a threshold value; and

,

for a running total exceeding the threshold value, generate and transmit an air alarm signal.

6. The optical imaging system of claim 2, wherein the threshold value includes a predetermined maximum value for a single air bubble.

7. The optical imaging system of claim 1, wherein:

the at least one processor is configured to execute the computer executable instructions to identify, using the first data, respective boundaries of the air bubble; and

,

determining the volume of the air bubble includes;

fitting a parametric function to the respective boundaries of the air bubble; and

,

integrating the parametric function to obtain the volume of the air bubble.

8. The optical imaging system of claim 1, wherein:

the at least one light source is for emitting second light;

the optical system is for;

receiving the second light transmitted by the first portion of the drip chamber; and

,

transmitting, to the at least one processor, second data characterizing the received second light; and

,

the at least one processor configured to execute the computer executable instructions to;

generate, using the second data, a plurality of successive images of the first portion of the drip chamber, during a predetermined time period;

determine, using the plurality of successive images, an absence of a drop pendant from the end of the drip tube, during the predetermined time period; and

,

generate and transmit an empty bag alarm signal.

9. The optical imaging system of claim 8, wherein the at least one processor configured to execute the computer executable instructions to:

generating an image of the end of the drip tube;

identify, using the image, a boundary of the end of the drip tube; and

,

use the boundary as at least one reference plane for determining the absence of the drop.

10. The optical imaging system of claim 1, wherein:

the at least one light source is for emitting third light;

the optical system is for;

receiving the third light transmitted by the third portion of the drip chamber; and

,

transmitting, to the at least one processor, third data characterizing the received third light; and

,

the at least one processor configured to execute the computer executable instructions to;

create an image of the third portion of the drip chamber;

determine, using the image;

an absence of fluid in the third portion of the drip chamber;

or,

a fluid level in the third portion below a predetermined level; and

,

generate and transmit an empty bag alarm or the air alarm signal.

11. The optical imaging system of claim 1, wherein:

the at least one light source consists of a single light source;

or,

the at least one light source consists of three light sources.

12. An optical imaging system for use with an infusion tube having a drip chamber including a first portion with a drip tube, a second portion with an exit port, and a third portion located between the first and second portions, the optical imaging system comprising:

an illumination system including at least one light source for emitting light;

an optics system including;

first, second, and third lenses for receiving and transmitting the light transmitted through the first, second, and third portions, respectively; and

,

first, second, and third image sensors for;

receiving the light from the first, second, and third lenses, respectively; and

,

generating and transmitting data characterizing the light received from the first, second, and third lenses;

a memory element for storing computer executable instructions; and

,

at least one processor configured to execute the computer executable instructions to generate, using the data, first, second, and third images of the first, second, and third portions, respectively.

13. The optical imaging system of claim 12, wherein:

the first portion includes a drop pendant from the drip tube and the third portion includes a meniscus for fluid in the drip chamber; and

,

the at least one processor configured to execute the computer executable instructions to calculate a volume of the drop using the first image and calculate a level for the meniscus using the third image.

14. The optical imaging system of claim 12, wherein:

the second portion includes an air bubble; and

,

the at least one processor configured to execute the computer executable instructions to calculate a volume of the air bubble using the second image.

15. The optical imaging system of claim 12, wherein:

the at least one light source consists of a single light source;

or,

the at least one light source consists of three light sources.

16. A method of imaging an infusion tube having a drip chamber and an output tube, wherein the drip chamber includes a first portion with a drip tube, a second portion with an exit port, and a third portion located between the first and second portions, comprising:

storing computer readable instructions in a memory element;

emitting first light from at least one light source;

receiving, using an optical system, the first light transmitted by the output tube or the second portion;

transmitting, using the optical system, first data characterizing the received first light; and

,

executing, using at least one processor, the computer executable instructions to;

detect, using the first data, an air bubble in the output tube or the second portion; and

,

determine a volume of the detected air bubble.

17. The method of claim 16, further comprising executing, using the at least one processor, the computer executable instructions to:

compare the volume to a threshold value; and

,

for a volume exceeding the threshold value, generate and transmit an air alarm signal.

18. The method of claim 16, wherein:

detecting an air bubble in the output tube or the second portion includes detecting, during a predetermined time period, a plurality of air bubbles sequentially passing through the output tube or the second portion;

determining a volume of the detected air bubble includes determining a respective volume for each air bubble in the plurality of air bubbles as said each air bubble is detected; and

,

determining a volume of the detected air bubble includes calculating a running total of the respective volumes as the respective volumes are determined.

19. The method of claim 18, further comprising executing, using the at least one processor, the computer executable instructions to:

determine that the respective volume for a last air bubble passing in sequence through the output tube or the second portion increases the running total beyond a predetermined maximum value; and

,

generate and transmit an air alarm signal.

20. The method of claim 18, further comprising executing, using the at least one processor, the computer executable instructions to:

compare the running total to a threshold value; and

,

for a running total exceeding the threshold value, generate and transmit an air alarm signal.

21. The method of claim 17, wherein the threshold value includes a predetermined maximum value for a single air bubble.

22. The method of claim 16, further comprising executing, using the at least one processor, the computer executable instructions to identify, using the first data, respective boundaries of the air bubble;

and, wherein;

determining the volume of the air bubble includes;

fitting a parametric function to the respective boundaries of the air bubble; and

,

integrating the parametric function to obtain the volume of the air bubble.

23. The method of claim 16, wherein:

the at least one light source is for emitting second light; and

,

the optical system is for;

receiving the second light transmitted by the first portion of the drip chamber; and

,

transmitting, to the at least one processor, second data characterizing the received second light; and

,

the method further comprising executing, using the at least one processor, the computer executable instructions to;

generate, using the second data, a plurality of successive images of the first portion of the drip chamber, during a predetermined time period;

determine, using the plurality of successive images, an absence of a drop pendant from the end of the drip tube, during the predetermined time period; and

,

generate and transmit an empty bag alarm signal.

24. The method of claim 23, further comprising executing, using the at least one processor, the computer executable instructions to:

generating an image of the end of the drip tube;

identify, using the image, a boundary of the end of the drip tube; and

,

use the boundary as at least one reference plane for determining the absence of the drop.

25. The method of claim 16, wherein:

the at least one light source is for emitting third light; and

,

the optical system is for;

receiving the third light transmitted by the third portion of the drip chamber; and

,

transmitting, to the at least one processor, third data characterizing the received third light; and

,

the method further comprising executing, using the at least one processor, the computer executable instructions to;

create an image of the third portion of the drip chamber;

determine, using the image;

an absence of fluid in the third portion of the drip chamber;

or,

a fluid level in the third portion below a predetermined level; and

,

generate and transmit an empty bag alarm or the air alarm signal.

26. The method of claim 16, wherein:

the at least one light source consists of a single light source;

or,

the at least one light source consists of three light sources.

27. A method of imaging an infusion tube having a drip chamber including a first portion with a drip tube, a second portion with an exit port, and a third portion located between the first and second portions, comprising:

storing computer readable instructions in a memory element;

emitting light using at least one light source;

receiving and transmitting, using first, second, and third lenses, the light transmitted through the first, second, and third portions, respectively;

receiving, using first, second, and third image sensors, the light from the first, second, and third lenses, respectively;

generating and transmitting, using the first, second, and third image sensors, data characterizing the light received from the first, second, and third lenses; and

,

executing, using at least one processor, the computer executable instructions to generate, using the data, first, second, and third images of the first, second, and third portions, respectively.

28. The method of claim 27, wherein:

the first portion includes a drop pendant from the drip tube and the third portion includes a meniscus for fluid in the drip chamber; and

,

the method further comprising executing, using the at least one processor, the computer executable instructions to calculate a volume of the drop using the first image and calculate a level for the meniscus using the third image.

29. The method of claim 27, wherein:

the second portion includes an air bubble; and

,

the method further comprising executing, using the at least one processor, the computer executable instructions to;

calculate a volume of the air bubble using the second image.

30. The method of claim 27, wherein:

the at least one light source consists of a single light source;

or,

the at least one light source consists of three light sources.