Patent ID: 9662444
Date: 2017-05-30
CPC Classifications: A61M

Claim:
1. A device to indicate a state of fluid in a fluid supply container of an infusion system, comprising: a fluid lumen having a first end and a second end, the first end fluidly coupled to a fluid container, wherein the fluid lumen defines a flow pathway with a first point along the pathway having a first cross-sectional area that varies relative to a second cross-sectional area at a second point along the pathway moving along the fluid lumen from the first end toward the second end, and wherein the cross-sectional area of any point along the pathway remains constant relative to itself, and wherein the cross sectional area moving along the pathway varies as defined by a predetermined, fixed profile, wherein the second end of the fluid lumen is connected to a drip chamber of a drug infusion system such that fluid flows from the fluid lumen into the drip chamber; wherein the fluid lumen includes a series of elongated, horizontally oriented portions through which fluid flows in a horizontal direction and a series of elongated, vertically oriented portions through which fluid flows in a distal direction, and wherein the horizontally oriented portions and vertically oriented portions are connected by a series of bends in the fluid lumen; a pressure sensor in fluid communication with the fluid lumen so as to measure static fluid pressure in the fluid lumen, the static fluid pressure being based on a column height of fluid in the fluid lumen; and an indicator configured to generate a signal based upon a predetermined change in static fluid pressure as measured by the pressure sensor.