BACKGROUND

Intravenous (IV) fluid delivery pumps are used to deliver fluid to a patient or to draw out fluid from a patient's body wherein the patient can be a human or animal. A delivery pump may be, for example, a piston-type pump that drives fluid by moving a piston up-and-down relative to fluid contained in a piston chamber. The pump may further include valve actuators on either side of the piston. The piston and the valve actuators may interface with the piston chamber and inlet-side and outlet-side valves on a disposable cassette. The upward stroke of the piston movement creates a pressure differential that forces fluid out of the piston chamber toward the patient.

Such pumps typically include one or more pressure sensors that measure fluid pressure along a fluid pathway. The valves on the disposable selectively control the flow of fluid into and out of the piston chamber. The valves and the actuators that engage therewith are critical components that are subject to wear and failure. The failure of such valves or actuators can result in large flow rate errors, which can be harmful for a patient, and can also result in other problems related to the delivery of fluid to the patient.

Current systems do not provide for the monitoring of proper valve or actuator function. In view of the foregoing, there is a need for improved systems and devices for monitoring proper valve function in a drug infusion piston pump.

SUMMARY

Described herein is a medical fluid infusion system including a pump system configured to deliver a fluid drug to a patient. The system includes a pump, such as a piston pump, for driving fluid to a patient. One or more pressure sensors are configured to measure and detect changes in fluid pressure in a fluid flow line of the infusion system. The changes in fluid pressure, when detected, can be an indication of proper or improper functioning of a valve system of the pump system of the fluid infusion system.

In one aspect, there is disclosed a fluid infusion system for delivery of a fluid medicant to a patient, comprising: a fluid line through which fluid flows toward the patient; a first valve position along the fluid line, wherein the first valve opens to permit fluid flow through the fluid line and closes to prohibit fluid flow through the fluid line; a first pressure sensor positioned along the fluid line, wherein the first pressure sensor measures fluid pressure at a location in the fluid line near the first valve; and a processor coupled to the first pressure sensor, wherein the processor is configured to detect an occurrence of a fluid pressure spike at the first valve, and wherein the processor is configured to compare data associated with the fluid pressure spike to predetermined criteria in order to determine whether the first valve is functioning properly, and wherein the processor emits a signal indicative of whether the first valve is functioning properly.

In another aspect, there is disclosed method of detecting a condition of a valve system in a fluid infusion system with a valve actuator that moves from occluding to non-occluding positions, comprising: detecting a change in fluid pressure that occurs in the fluid line when the valve actuator moves from a non-occluding position to an occluding position; obtaining profile data related to the change in fluid pressure; and comparing the profile data to predetermined criteria to determine a condition of the valve.

The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will be apparent from the description and drawings, and from the claims.

