Patent CA-1184820-A (CA)
Inventor: MARTINEZ FELIX J
IPC: A61M5/00
Filed: 1984-03-30
Granted: 1985-04-02
Abstract: ABSTRACT          Improvements and accessories for a septum closed T-shaped blood access device adapted for implantation into a patient.  The implantable device has a stem portion extending above the skin of the patient and defining a septum closed opening into the device.          The improvements include an improved septum having a         groove in the side thereof encircling the septum and an elastomeric ring carried within the side groove, an improved needle assembly which provides access to the circulatory system through the septum, and a flexible cap for sealing the stem of the implantable device from the outside atmosphere which may be fitted in place or removed without the necessity of specialized tools.          One of the accessories is a septum assembly insertion tool which simultaneously inserts the septum, a pressure plate and a retaining ring into the stem cavity of the implantable device.  Another accessory is specialized forceps clamp for gripping the flanged upper edge of the stem of the implantable device.  The clamp has curved finger holds which permit the stem of the implanted device to be stabilized during insertion of the septum assembly.      Yet another accessory is a back-up septum system for plugging the cavity in the stem of the implanted device above the principal septum when the principal septum begins to fail.  The back-up septum system comprises a specially designed spacer member, a septum conforming generally to the shape of the stem cavity above the retaining ring for the principal septum and a specially designed clamp for holding and compressing the back-up septum within the stem cavity.  The back-up system permits continued access to the circulatory system until assistance can be obtained in replacing the primary septum.          A final accessory is a hemispherical implant cap which protects the stem cavity of the implantable device during implantation of the device in the body.      This application is a division of Canadian Application No. 376,507 filed April 29, 1981.    This application relates to improvements in, and accessories for, implantable septum closed blood access devices of the type disclosed in co-pending Canadian application Serial No. 374,940, filed April 8, 1981.    Various approaches to implanted blood access devices are known, however, none of these have been entirely satisfactory. Shunt techniques have problems of infection, clotting and erosion. The arteriovenous fistula has some advantages over shunts, but there is a need for recurring needle puncture and there are still infection problems as well as other disadvantages.    It is also known to provide implanted blood access devices wherein access to the circulatory system is accomplished by means of a percutaneous spigot valve.    In said co-pending application Serial No. 374,940, there is disclosed an implantable generally tubular T-shaped structure in which the stem of the T is constructed and arranged to cooperate with a needle structure that penetrates a septum seal means at the junction of the stem of the T with the balance of the T structure.  By reason of the structure of the invention, the interior stemmed portion of the T can be rinsed clean and sterilized between each use without elaborate procedures, thus minimizing the likelihood of infection as a result of access to the circulatory system.  The invention thus provides an implantable blood access device which may be semi-permanently installed into the circulatory system and used repeatedly.  This invention also has a low profile body external portion which minimizes the possible catching of clothing and the like on the external portion.    Further features of the invention of said co-pending application Serial No. 374,940 include a specialized septum construction, a cooperating needle carrier structure and a cap which seals the flanged edge of the external.