Abstract This invention pertains to the use of catheters and the sterilized protection of their exterior surface as they are inserted into a patient and particularly for catheters used with intravascular feedings and transfusions and pressure determining systems, suprapubic catheterization and spinal taps. A needle or stylet within the catheter is used for the initial penetration and usually assembled and packaged with the catheter and sheath of this invention. The protective sheath is a very thin plastic tubular member which is a loose sliding fit on the outer diameter of the catheter. This sleeve remains mounted on the catheter as the catheter is inserted into the patient. The loose sheath is disposed to collapse upon itself up to and around the hub of the inserting catheter. As and during its collapse the sheath acts as a guard to prevent contamination of the inserting member as it is advanced into the patient. The sheath member may be approximately one-third larger than the diameter of the catheter on which it is mounted and is approximately one-thousandths of an inch in thickness which is just sufficient to permit heat sealing to form the tube and to provide a reasonable protection against manipulative handling. In its initial mounted condition the end of the sheath is brought to or very near the sharp end of the inserting member.
In combination with a flexible catheter for percutaneous use with a patient there is provided a flexible protective sheath slidably mounted on the midshaft portion, said combination including: (a) a flexible catheter of determined length and having an entering end and a hub end and with that midshaft portion of said catheter forwardly of the hub having a selected outside relatively constant bore; (b) a stiff bore puncturing member slidably carried in the bore of the catheter and removable through the hub end after the desired penetration of the skin of a patient has been achieved, and (c) a very thin flexible plastic sheath of tube-like form whose wall thickness is less than twothousandths of an inch in thickness and formed and sized so as to provide a sliding fit on the outer diameter of the midshaft of the catheter which it is to protect, the tube size being about one-third larger than the midshaft portion of the catheter for which it provides the protection, said sheath in an unmounted condition being open at both ends and when mounted having a length sufficient to extend from the skin-entering end of said catheter to a determined larger stop portion such as the hub of the catheter, said mounted sheath particularly adapted to engage the skin at the point of penetration and to be engaged by the skin at this opening to prevent further forward progress of the sheath whereat said sheath slides on the midshaft of the catheter and to the extent of shortening the sheath length progressively collapses into accordion-like folds as the catheter is caused to enter the entrance into and through the skin, the sheath providing a sliding guard continuously protecting against accidental contact of the outer surface diameter of the uninserted portion of the midshaft of the catheter by the user of the instrument during both the initial and progressive insertion through the skin, said sheath in its folded and unfolded portion remaining on the uninserted portion of the midshaft of the catheter during inserted use in a patient.
Claim 2
Dependent Claim
342 words
In combination with a flexible catheter for percutaneous use with a patient there is provided a flexible protective sheath slidably mounted on the midshaft portion, said combination including: (a) a flexible catheter of determined length and having an entering end and a hub end and with that midshaft portion of said catheter forwardly of the hub having a selected outside relatively constant bore; (b) a stiff bore puncturing member slidably carried in the bore of the catheter and removable through the hub end after the desired penetration of the skin of a patient has been achieved, and (c) a very thin flexible plastic sheath of tube-like form whose wall thickness is less than twothousandths of an inch in thickness and formed and sized so as to provide a sliding fit on the outer diameter of the midshaft of the catheter which it is to protect, the tube size being about one-third larger than the midshaft portion of the catheter for which it provides the protection, said sheath in an unmounted condition being open at both ends and when mounted having a length sufficient to extend from the skin-entering end of said catheter to a determined larger stop portion such as the hub of the catheter, said mounted sheath particularly adapted to engage the skin at the point of penetration and to be engaged by the skin at this opening to prevent further forward progress of the sheath whereat said sheath slides on the midshaft of the catheter and to the extent of shortening the sheath length progressively collapses into accordion-like folds as the catheter is caused to enter the entrance into and through the skin, the sheath providing a sliding guard continuously protecting against accidental contact of the outer surface diameter of the uninserted portion of the midshaft of the catheter by the user of the instrument during both the initial and progressive insertion through the skin, said sheath in its folded and unfolded portion remaining on the uninserted portion of the midshaft of the catheter during inserted use in a patient.
Claim 3
Dependent Claim
20 words
A combination of sheath and catheter as in claim 1 in which the skin puncturing member is a metal stylet.
Claim 4
Dependent Claim
21 words
A combination of sheath and catheter as in claim 1 in which the skin puncturing member is a hollow metal needle.