SYRINGE PUMP WITH IMPROVED FLOW MONITORING

• US 20140114238A1
• Filed: 10/24/2012
• Published: 04/24/2014
• Est. Priority Date: 10/27/2011
• Status: Active Grant

• Current Assignee: Zyno Medical, LLC
• Original Assignee: Zyno Medical, LLC
• Inventors: Lee, Chaoyoung, Zhang, Mei, Lu, Cunyou
• Granted Patent: US 9,375,531 B2
• Time in Patent Office: Days
• US Class Current: 604/67
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/3375 Acoustical, e.g. ultrasonic, measuring means
• CPC Class Codes: A61M 5/1452 pressurised by means of pistons
• CPC Class Codes: A61M 5/1456 with a replaceable reservoir comprising a piston rod to be moved into the reservoir, e.g. the piston rod is part of the removable reservoir
• CPC Class Codes: A61M 5/16804 Flow controllers
• CPC Class Codes: A61M 5/16831 Monitoring, detecting, signalling or eliminating infusion flow anomalies low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066
• CPC Class Codes: A61M 5/16854 by monitoring line pressure
• CPC Class Codes: A61M 5/16877 Adjusting flow; Devices for setting a flow rate
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence

Abstract

A syringe pump provides a controlled metering of the medicament from a syringe by movement of the syringe plunger while also measuring flow from the syringe with a flow sensor. Simultaneous monitoring of flow command implicit in control of the syringe plunger and an actual flow provides additional safety and detection of irregularities in the delivery of the medicament.

Claims

1. A syringe pump comprising:

a housing adapted to hold a syringe holding a liquid medicament;

a motor drive attached to the housing having a portion adapted to hold a plunger portion of the syringe to move the plunger portion within a tube portion of the syringe according to a motor drive signal to eject the medicament from the syringe;

a flow sensor adjacent to a flow of medicament from the syringe to monitor the flow; and

an electronic controller communicating with the motor drive and the flow sensor to detect a flow error and to deactivate or adjust the motor drive upon detection of the flow error.

2. The syringe pump of claim 1 further including an alarm indicator to a user of the syringe pump and wherein the electronic controller activates the alarm upon detection of a flow error.

3. The syringe pump of claim 2 wherein the flow error is a flow rate outside of a predetermined range.

4. The syringe pump of claim 3 wherein the electronic controller provides a pump speed command to the motor drive and wherein a predetermined range is a function of pump speed command.

5. The syringe pump of claim 4 wherein the flow sensor receives an IV tube passing from the syringe to a patient to operate through the IV without piercing the IV tube.

6. The syringe pump of claim 5 wherein the flow sensor deduces flow from pressure differential along a length of the IV tube.

7. The syringe pump of claim 5 wherein the flow sensor deduces flow through a change in wave speed through the liquid as measured along an axis of the tube.

8. The syringe pump of claim 5 wherein the flow sensor deduces flow through at least one of a change in tubing deformation or moving pattern of minor optical inclusions in the medicament by utilizing at least one optical sensor.

9. The syringe pump of claim 4 wherein the flow sensor is integrated into an IV tube attached to the syringe and communicating with a patient.

10. The syringe pump of claim 9 wherein the flow sensor deduces flow from thermal conduction of the medicament.

11. The syringe pump of claim 9 wherein the flow sensor is a mechanical wheel rotating within the medicament in response to medicament flow.

12. The syringe pump of claim 11 wherein the rotating of the wheel is detectable by at least one of a detecting of change of:

magnetic field, light energy, and capacitance caused by rotation of the wheel.

13. The syringe pump of claim 1 wherein the electronic controller further deduces a flow rate from a pump motor command and data related to a geometry of the syringe.

14. The syringe pump of claim 1 further including a pressure sensor communicating with the electronic controller and indicating a pressure of the medicament within an IV line attached to the syringe.

15. The syringe pump of claim 14 wherein the pressure sensor is a component of the flow sensor.

16. A syringe pump comprising:

a housing adapted to hold a syringe holding a liquid medicament;

a motor drive attached to the housing having a portion adapted to hold a plunger portion of the syringe to move the plunger portion within a tube portion of the syringe according to a motor drive signal to eject the medicament from the syringe;

a sensor providing a signal confirming connection between the syringe and the patient;

an electronic controller communicating with the motor drive and the sensor to detect a disconnection of the syringe from the patient to deactivate the motor drive upon detection of the disconnection.

17. The syringe pump of claim 16 wherein the sensor is selected from the group consisting of at least one of pressure sensor, a piezoelectric transducer, accelerometer, and a MEMS sensor

18. The syringe pump of claim 16 wherein the sensor is positioned at a distal end of an IV line remote from the syringe.

19. The syringe pump of claim 16 wherein the sensor communicates with the electronic controller through one of a wired and wireless connection.

20. A flow sensor for sensing the flow of medicament comprising an optical system positionable next to a lumen of known dimensions for receiving light there from to discerning a moving pattern of minor optical inclusions in the medicament and thereby deduce a flow rate through the lumen.