In-line retractable safety catheter needle insertion assembly

Abstract

Disclosure of methods and apparatus providing bases for design of compact catheter insertion needle retraction safety devices wherein actuators are displaced away from slender needle sheathing bodies to initiate a needle retraction cycle for safely containing a catheter insertion needle after use. Such actuation guards against inadvertent acts, such as depression of an actuator, which may result in untimely needle retraction. Four embodiments of the instant invention are disclosed. In one embodiment, needle retracting energy is stored as a catheter insertion needle is extended for use and is expended to retract the needle into safe containment. Other embodiments comprise power assist mechanisms which store energy during an initial phase of needle retraction to be used to enhance and assist needle retraction during a needle retraction completing phase. In some embodiments, retraction is facilitated by a pair of rigid, elongated, hingedly interconnected arms which are further pivotally coupled to a needle hub assembly and to a device body such that one arm is rotated approximately 180.degree. to retract the needle a distance greater than the length of the so rotated arm to facilitate retraction actuation. One power assist mechanism comprises a part molded as a distortable member of one of the arms. To realize low cost manufacture, the operating device can be made from as few as two injection molded parts. A readily viewable, blood flash chamber permits early detection of evidence of needle entry into a blood vessel.