A medical insertion device includes an introducer assembly, a needle, and a housing. The introducer assembly includes a dilator coaxially disposed in a sheath, the dilator removably engaged to the sheath in an insertion configuration. The needle is coaxially disposed in the dilator, the needle having a distal tip and a proximal end coupled to a needle hub. The housing may be removably engaged to the dilator. The needle hub is movably disposed in the housing between a first locked position, a second locked position, and a third locked position.

A catheter assembly includes: a catheter having an inner cavity extending along a center axis of the catheter, the catheter comprising, on a distal side, a tapered portion that is tapered in a distal direction; and an inner needle retractably located in the inner cavity. The inner needle comprises, on a distal side, a blade surface that is inclined with respect to a center axis of the inner needle. The tapered portion covers a proximal end portion of the blade surface in an assembled state in which the inner needle is located in the inner cavity, and an inner shape of a distal-most end of the tapered portion conforms to the blade surface.

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.

A medical insertion device includes an introducer assembly, a needle, and a housing. The introducer assembly includes a dilator coaxially disposed in a sheath, the dilator removably engaged to the sheath in an insertion configuration. The needle is coaxially disposed in the dilator, the needle having a distal tip and a proximal end coupled to a needle hub. The housing may be removably engaged to the dilator. The needle hub is movably disposed in the housing between a first locked position, in which the distal tip of the needle extends a first length from a distal end of the dilator, a second locked position, in which the distal tip of the needle extends a second length from the distal end of the dilator less than the first length, and a third locked position, in which the distal tip of the needle is within the dilator.

A medical insertion device includes an introducer assembly, a needle, and a housing. The introducer assembly includes a dilator coaxially disposed in a sheath, the dilator removably engaged to the sheath in an insertion configuration. The needle is coaxially disposed in the dilator, the needle having a distal tip and a proximal end coupled to a needle hub. The housing may be removably engaged to the dilator. The needle hub is movably disposed in the housing between a first locked position, a second locked position, and a third locked position.

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.

A catheter assembly includes: a catheter having an inner cavity extending along a center axis of the catheter, the catheter comprising, on a distal side, a tapered portion that is tapered in a distal direction; and an inner needle retractably located in the inner cavity. The inner needle comprises, on a distal side, a blade surface that is inclined with respect to a center axis of the inner needle. The tapered portion covers a proximal end portion of the blade surface in an assembled state in which the inner needle is located in the inner cavity, and an inner shape of a distal-most end of the tapered portion conforms to the blade surface.

A medical insertion device includes an introducer assembly, a needle, and a housing. The introducer assembly includes a dilator coaxially disposed in a sheath, the dilator removably engaged to the sheath in an insertion configuration. The needle is coaxially disposed in the dilator, the needle having a distal tip and a proximal end coupled to a needle hub. The housing may be removably engaged to the dilator. The needle hub is movably disposed in the housing between a first locked position, in which the distal tip of the needle extends a first length from a distal end of the dilator, a second locked position, in which the distal tip of the needle extends a second length from the distal end of the dilator less than the first length, and a third locked position, in which the distal tip of the needle is within the dilator.

An insertion device for use in assisting with the placement of a medical device within the body of a patient is disclosed. For example, the insertion device can be employed to assist with the placement of an introducer, which provides a conduit for insertion of a catheter into the body. In one embodiment, the insertion device comprises a needle that is removably disposed within a bore defined by the medical device, and a needle retraction assembly. The needle retraction assembly can position the needle in any one of a first position wherein a distal tip of the needle is disposed a predetermined distance distal to a distal end of the medical device, a second position wherein the needle distal tip is disposed distal but proximate to the distal end of the medical device, and a third position wherein the needle distal tip is retracted within the medical device bore.