Method and apparatus for regulating intravenous flow of a liquid

Abstract

An intravenous apparatus for administering liquids to a patient, including an elongated supply tube having a first end which is adapted to be connected to a reservoir of liquid. A flow-regulating device is attached to the remote end of the supply tube. A control tube having a length approximately the same as the supply tube is adapted to hang alongside the supply tube. Within the flow-regulating device is a flexible member such as a tube, bladder or diaphragm--with liquid that is being furnished by the supply tube passing interiorly of said flexible member, and there being some means for externally pressurizing said flexible member. A preferred means for pressurizing the flexible member is a column of liquid maintained in the control tube, with the control liquid having the same specific gravity as that of the supply liquid. A check valve is provided so that liquid may temporarily pass out of the supply tube and into the control tube, until a desired height of liquid has been achieved in the control tube. When the flow-regulating device is located very near a needle which is inserted into a patient's arm or leg, ordinary movement of that arm or leg will not change the rate of flow--because the height of liquid (i.e., head) changes simultaneously in both tubes. The flow-regulating device may be quite small, with a typical bladder or tube being about one inch long, and a rigid housing for said bladder being only slightly longer.

Dependencies are inferred from the claim text.