Burn patient resuscitation system

• US 8,597,273 B2
• Filed: 04/03/2012
• Issued: 12/03/2013
• Est. Priority Date: 03/19/2007
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Salinas, Jose, Kramer, George C., Drew, Guy A.
• Primary Examiner(s): Sirmons, Kevin C
• Assistant Examiner(s): CARPENTER, WILLIAM R
• Application Number:
  US13/438,434
• Publication Number:
  US 20120283631A1
• Time in Patent Office: 609 Days
• Field of Search: 600/582, 604/31, 604/65, 604/66, 604/131, 604/151, 604/503, 604/504
• US Class Current: 604/503
• CPC Class Codes: A61B 5/20 for measuring urological functions restricted to the evaluation of the urinary system A61B5/4375 takes precedence
• CPC Class Codes: A61B 5/412 Detecting or monitoring sepsis
• CPC Class Codes: A61M 2202/0496 Urine
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: G16H 10/60 for patient-specific data, e.g. for electronic patient records
• CPC Class Codes: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

A system for operating a semi-closed loop and/or a closed loop resuscitation of a burn patient in view of patient information and other physiological data gathered by the system. The system in at least one embodiment includes an urine sensor, an infusion pump and a processor that controls the operation of the infusion pump at least in part from a signal received from the urine sensor.

Claims

1. A system for use in resuscitating a patient comprising:

a urine sensor;

an infusion pump; and

a processor connected to said urine sensor and said infusion pump, said processor having

means for calculating an infusion rate using an infusion rate model based on at least a current infusion rate, a current urinary output, and infusion rate model based constants, the new infusion rate is calculated using the following equation

2. The system according to claim 1, wherein the infusion rate constant decreases based on hours post-burn in at least two steps.

3. The system according to claim 1, wherein the urinary output error is further multiplied by at least one of a modifier based on a patient'"'"'s weight, a modifier based on a percentage of a total body surface area burned, and a Gaussian function calculated using an end point of a target urinary output range furthest from the current urinary output.

4. The system according to claim 1, wherein the urinary output error is further multiplied by a Gaussian function calculated using an end point of a target urinary output range furthest from the current urinary output, where the Gaussian function is calculated using

G=1−

Ae<sup>−

(X−

B)2/C2</sup>

where A is set to 1;

X is set to the current urinary output;

B is set to the furthest end point of the target urinary output range; and

C is set to 5.

5. The system according to claim 1, further comprising a timer connected to said processor, said calculating means calculates a new infusion rate when said timer expires after running for a predetermined time.

6. The system according to claim 5, wherein the predetermined time is based on hours post burn.

7. The system according to claim 1, further comprising a display, and

said processor further includes means for driving said display and receiving information from said display of information entered by a user including an infusion rate different than the infusion rate calculated, and

said controlling means operates the infusion pump at the different infusion rate received from the user until a new infusion rate is received or calculated.

8. The system according to claim 1, further comprising a selector with at least two positions including a closed loop position and a semi-closed loop position, said selector is in communication with said processor.

9. The system according to claim 1, further comprising means for notifying medical staff when a problem has arisen with the patient.

10. The system according to claim 1, further comprising means for notifying medical staff when a problem has arisen with the system.

11. The system according to claim 1, wherein said urine sensor includes a drop rate sensor.

12. A system for use in resuscitating a patient comprising:

a urine sensor;

an infusion pump;

a timer; and

a processor connected to said urine sensor, said infusion pump, and said timer, said processor having

means for calculating an infusion rate in response to a signal from said timer and based on at least the current infusion rate, the current urinary output, infusion rate model based constants, the patient'"'"'s weight, the percentage of total body surface area, and a Gaussian function centered on a target urinary output, and

means for controlling operation of said infusion pump based on the calculated infusion rate.

13. The system according to claim 12, wherein the infusion rate model based constants include an infusion rate constant and a urinary output constant.

14. The system according to claim 12, further comprising a display, and

said processor further includes means for driving said display and receiving information from said display of information entered by a user including an infusion rate different than the infusion rate calculated, and

said controlling means operates the infusion pump at the different infusion rate received from the user until a new infusion rate is received or calculated.

15. The system according to claim 12, further comprising a selector with at least two positions including a closed loop position and a semi-closed loop position, said selector is in communication with said processor.

16. The system according to claim 12, wherein said calculating means uses the following equation

17. The system according to claim 16, wherein the Gaussian function is calculated using an end point of a target urinary output range furthest from the current urinary output, where the Gaussian function is calculated using

G=1−

Ae<sup>−

(X−

B)2/C2</sup>

where A is set to 1;

X is set to the current urinary output;

B is set to the furthest end point of the target urinary output range; and

C is set to 5.

18. The system according to claim 12, further comprising means for notifying medical staff when a problem has arisen with at least one of the patient and the system.

19. A system for use in resuscitating a patient comprising:

a urine sensor;

an infusion pump;

receiving means for receiving patient data including percentage of total body surface area burned and time since the patient was burned;

first means for calculating an initial infusion rate based on at least the received patient data;

second means for calculating an urinary output error based on a difference between a target urinary output and a current urinary output provided by said urine sensor;

third means for calculating a new infusion rate based on at least the calculated urinary output error multiplied by a constant calculated in part based on an exponential function with the input of hours post burn for the patient with the result being added to the current infusion rate;

outputting means for outputting the new infusion rate to said infusion pump; and

a timer for controlling the operation of said second means, said third means and said outputting means.

20. The system according to claim 19, further comprising a processor having said receiving means, said first means, said second means, said third means, and said outputting means.