Safety intravenous cannulas

摘要

A safety intravenous cannula and catheter device is disclosed. The device permits easy insertion of a cannula made of a biocompatible material into the vein with a guide needle and withdrawal of the guide needle into a safety chamber with an in- built locking mechanism with completely prevents removal and/reuse of the needle. The needle before insertion is protected by a biocompatible sheath which when inserted into the vein and after withdrawal of the needle acts as catheter. Similarly, after withdrawal the needle is locked inside a safety chamber in such a manner that at no time does the user come into contact with the needle or in any danger of accidental injury.

主权项

1. A catheter insertion device which comprises in combination:
a cannula assembly having a catheter detachably attached to a catheter holder at the distal end and at least one attachment site at the proximal end, and having a lumen extending from the distal end to the proximal end; a guide needle mounted on a needle hub attached to a flash back chamber of the guide needle for positioning the cannula assembly to an operative position and sliding or moving the guide needle, wherein the catheter is slidably coaxially mounted on the outer circumference of the guide needle wherein the guide needle is in fluid communication with the lumen; a safety transfer chamber assembly detachably connected to the cannula assembly at the attachment site through a front cap, wherein the safety transfer chamber assembly comprises an outer sleeve slidably mounted around an inner sleeve, the needle hub projecting radially outward of the inner and outer sleeves to facilitate gripping thereof and cooperating with the inner sleeve to form a first complementary interlocking mechanism (P) at a first locking position wherein, upon retracting the guide needle from the catheter, the needle hub interacts with the inner sleeve to prevent forward movement of the guide needle and reinsertion thereof in the catheter, further retraction of the needle hub causing the inner sleeve to retract within the outer sleeve, the inner and outer sleeves being equipped with a second complementary interlocking mechanism such that in a fully retracted position of the inner sleeve, the guide needle is completely enclosed within the inner sleeve and the outer sleeve of the safety transfer chamber assembly and the inner sleeve locks with the outer sleeve at a second locking position, thereby preventing further axial or rotational movement of the two sleeves with respect to each other such that reuse of the guide needle is completely prevented.