Abstract: A valve element adapted to be positioned in the infeed for a catheter is disclosed. By slits in Y arrangement relative to each other, an automatically closable passage opening is formed therein. The passage is especially easy to locate for the catheter tip due to the fact that the valve element is provided on its proximal side with a truncated cone-shaped recess. In addition, due to the recess the flexibility of the gussets of material defined by the slits is enhanced, which gussets sealingly hug the outside of the catheter when the catheter is present The distal face of the valve may be provided also with a truncated cone-shaped recess.

Abstract: To securely introduce the distal tip of a spinal cannula through an epidural cannula into a spinal canal, a mandrel is placed in the epidural cannula. The mandrel is provided with a recess or guideway extending over its length. The guideway is aligned with an axial opening in the epidural cannula, so that the spinal cannula, when pushed forward through the recess, is guided positively to the axial opening and can pass through it unhindered, in order to get into the spinal canal. The mandrel includes a radially offset distal portion which enters and seals a curved, offset portion of the epidural cannula to avoid coring of tissue and to snap fittedly connect the mandrel and epidural cannula.

Abstract: A cannula assembly provides for secure protection of the cannula prior to use and safe disposal after use. A tubular resilient sleeve includes a longitudinal slot. The cannular includes a radial projection which, after use of the cannula, may be inserted within the slot and slid interiorly of the sleeve to lock the cannula in protected position. A cannula shield includes an adapter insertible into the slotted end of the sleeve to spread the slot and facilitate insertion of the cannula into the slot.