Infusion system and method of use which prevents over-saturation of an analog-to-digital converter

Patent metadata

Field	Value
Publication number	US-10596316-B2
Application number	US-201715648975-A
Country	US
Kind code	B2
Filing date	Jul 13, 2017
Priority date	May 29, 2013
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

To detect air in a fluid delivery line of an infusion system, infusion fluid is pumped through a fluid delivery line adjacent to at least one sensor. A signal is transmitted and received using the at least one sensor into and from the fluid delivery line. The at least one sensor is operated, using at least one processor, at a modified frequency which is different than a resonant frequency of the at least one sensor to reduce an amplitude of an output of the signal transmitted from the at least one sensor to a level which is lower than a saturation level of the analog-to-digital converter to avoid over-saturating the analog-to-digital converter. The signal received by the at least one sensor is converted from analog to digital using an analog-to-digital converter. The at least one processor determines whether air is in the fluid delivery line based on the converted digital signal.

First claim

What is claimed is:

1. An infusion system configured to improve detection of air in a fluid delivery line, the infusion system comprising:
a sensor configured to detect a first signal transmitted in a fluid delivery line;
an analog-to-digital converter electronically connected to the sensor, the analog-to-digital converter configured to convert the detected signal from analog to digital;
a hardware processor connected with the analog-to-digital converter, the hardware processor configured to:
determine that the detected first signal is saturated;
change an operating frequency of the sensor based on the determination of saturation;
transmit a second signal at the changed operating frequency; and
determine air in the fluid delivery line based on the transmitted second signal.

2. The infusion system of claim 1 , wherein the changed operating frequency is different than a resonant frequency of the sensor.

3. The infusion system of claim 1 , wherein the one or more hardware processors are further configured to determine the resonant frequency of the sensor.

4. The infusion system of claim 1 , wherein the one or more hardware processors are further configured to determine a minimum level for received signals.

5. The infusion system of claim 4 , wherein the one or more hardware processors are further configured to change the operating frequency to exceed the minimum level for received signals.

6. The infusion system of claim 1 , wherein the changed operating frequency is within ±50% of the resonant frequency.

7. An method of improving detection of air in a fluid delivery line, the method comprising:
detecting a first signal transmitted in a fluid delivery line;
converting the detected signal from analog to digital;
determining that the detected first signal is saturated;
changing an operating frequency of the sensor based on the determination of saturation;
transmitting a second signal at the changed operating frequency; and
determining air in the fluid delivery line based on the transmitted second signal.

8. The method of claim 7 , wherein the changed operating frequency is different than a resonant frequency of the sensor.

9. The method of claim 7 , further comprising the resonant frequency of the sensor.

10. The method of claim 7 , further comprising determining a minimum level for received signals.

11. The method of claim 10 , further comprising changing the operating frequency to exceed the minimum level for received signals.

12. The method of claim 7 , wherein the changed operating frequency is within ±50% of the resonant frequency.

13. An infusion system configured to improve detection of air in a fluid delivery line, the infusion system comprising one or more hardware processors configured to:
receive a first digital signal corresponding to a first signal detected by a sensor, wherein the first signal is responsive to a transmitted signal in a fluid delivery line;
determine that the first digital signal is saturated;
change an operating frequency of the sensor based on the determination of saturation;
transmit a second signal at the changed operating frequency; and
determine air in the fluid delivery line based on the transmitted second signal.

14. The infusion system of claim 13 , wherein the changed operating frequency is different than a resonant frequency of the sensor.

15. The infusion system of claim 13 , wherein the one or more hardware processors are further configured to determine the resonant frequency of the sensor.

16. The infusion system of claim 13 , wherein the one or more hardware processors are further configured to determine a minimum level for received signals.

17. The infusion system of claim 16 , wherein the one or more hardware processors are further configured to change the operating frequency to exceed the minimum level for received signals.

18. The infusion system of claim 13 , wherein the changed operating frequency is within ±50% of the resonant frequency.

Assignees

• Icu Medical Inc

Inventors

• Dumas Iii John Hicks
• Kotnik Paul T
• Sur Kunal
• Belkin Anatoly S
• Ruchti Timothy L

Classifications

• A61M2205/3327

  Measuring · CPC title

• A61M2205/3306

  Optical measuring means · CPC title

• A61M5/365

  Air detectors (A61M5/1684 takes precedence; in extracorporeal blood circuits A61M1/3626) · CPC title

• A61M2205/702

  automatically during use · CPC title

• A61M5/142

  Pressure infusion, e.g. using pumps · CPC title