IV catheter with retractable needle and laterally offset biasing element and needle retraction cavity

Inventors

Shaw, Thomas J. • Small, Mark • Zhu, Ni

Assignees

Retractable Technologies Inc

Abstract

An intravenous catheter introducer for medical use having a body, a frontal attachment that is disposed in transverse sliding engagement with a front part of the body, a hub tube assembly that is releasably supported by the frontal attachment, and a retractable catheter insertion needle and needle holder that are biased rearwardly by a spring offset laterally from the needle axis, whereby lateral repositioning of the body relative to the frontal attachment following vascular insertion moves a needle retraction cavity disposed inside the body into substantial coaxial alignment and causes the needle holder to be retracted into the needle retraction cavity.

Core Innovation

The invention relates to an intravenous catheter introducer for medical use comprising a body and a frontal attachment disposed in transverse sliding engagement with a front part of the body. A hub tube assembly is releasably supported by the frontal attachment and includes a hub, a cannula support, and a flexible cannula tube projecting forwardly from the hub. A rearwardly biased needle holder assembly is seated in the frontal attachment and projects forwardly with a base, a tubular needle holder along a first longitudinal axis, and an insertion needle projecting forwardly from the tubular needle holder through the hub tube assembly.

The needle holder assembly further includes a spring support post projecting forwardly from the base along a second longitudinal axis passing through a compressed coil spring disposed around and slidably engaging the spring support post forwardly of the base. The compressed coil spring is configured so that it does not surround the tubular needle holder, and no part of the insertion needle projects through any part of the compressed coiled spring. The body further comprises a needle retraction cavity that is offset laterally from the first longitudinal axis of the insertion needle prior to needle retraction.

Needle retraction is triggered by lateral movement of a body relative to a frontal attachment after vascular insertion. This moves the needle retraction cavity inside the body into coaxial alignment with the needle axis so that the needle holder assembly can retract into the needle retraction cavity. The described embodiment further includes a selectively removable needle cap with a locking member to prevent lateral body motion prior to use, and an annular fluid seal and a recessed, laterally offset elongate opening providing access to the needle retraction chamber.

In addition, an optional fluid sampling tool is documented with a fluid chamber behind the seal, a droplet sampling tip, and a rear filter housing. The fluid sampling tool configuration includes a fluid sample reservoir and a filter housed in a tubular filter housing with a cylindrical bore and a seated filter.

Claims Coverage

The independent claim includes at least three core inventive aspects: the compressed coil spring arrangement that biases a needle holder without allowing the insertion needle to pass through the spring, the laterally offset needle retraction cavity that becomes coaxially aligned with the needle axis via relative lateral movement, and the catheter introducer’s transverse sliding engagement and releasably supported hub tube assembly with an insertion needle projecting through the hub tube assembly.

The independent claim centers on a laterally offset needle retraction cavity and a compressed coil spring arrangement that biases a needle holder assembly while preventing the insertion needle from projecting through the compressed coil spring, combined with a catheter introducer architecture using a body and a frontal attachment in transverse sliding engagement and a releasably supported hub tube assembly.

Stated Advantages

Documented Applications

No documented applications found