Abstract: Syringe assemblies are described with at least two co-axially positioned cylinders that move relative to one another by action of a spring. Aspects of the syringe assemblies include a protective unit in which a first cylinder of a first length is attached to a second cylinder of shorter second length. In different embodiments, a protective unit is formed of a single or singularly fabricated cylinder. The different protective units may be used with a syringe in which action of a plunger to push a plunger tip into contact with a distal wall of the syringe cylinder to discharge fluid located inside the syringe but does not immediately release the protective unit relative to the syringe cylinder to shield a needle.

Abstract: Syringe assemblies are described with at least two co-axially positioned cylinders that move relative to one another by action of a spring. Aspects of the syringe assemblies include a protective unit in which a first cylinder of a first length is attached to a second cylinder of shorter second length. In different embodiments, a protective unit is formed of a single or singularly fabricated cylinder. The different protective units may be used with a syringe in which action of a plunger to push a plunger tip into contact with a distal wall of the syringe cylinder to discharge fluid located inside the syringe but does not immediately release the protective unit relative to the syringe cylinder to shield a needle.

Abstract: A catheter for spinal anesthesia has a needle arranged therein. The length of the needle is smaller than the length of the catheter. The rear end of the needle is connected to a handling thread for pulling the needle out of the catheter towards the proximal end. The needle is designed as a hollow needle with a lateral opening. When advancing the tip of the needle into the subarachnoid space, liquor flows through the opening into the catheter, allowing for verification of successful puncture. During puncture of the dura with the tip of the needle, the puncture hole is widened by the front end of the catheter so that the catheter fills the puncture hole completely. After puncture, the needle is withdrawn by pulling the handling thread.

Abstract: An infusion catheter adapter and cap assembly, the catheter adapter has a housing with an input, an output and a side port, normal to the housing axis, which has a cap. The cap is fixedly attached to the housing by a living hinge with a retaining knob. The retaining knob on the living hinge conjugates with a groove on the housing. The groove is formed as a transverse channel defined by two opposing locking fingers. The position of the retaining knob in the groove is further ensured by a recess on the knob which conjugates with a peak in the groove to center and lock the retaining knob in the groove.