UNIEVER DISPOSABLE SPINAL ANESTHESIA NEEDLE／Disposable Spinal Anesthesia Needles (Pencil Point)

Parts Details

Assembly

Pencil Point (Conical-Shape)

Pencil Point
(Bullet-Shape)

Entire needle image

Introducer

*Click to zoom the image

■ Product Specification

Product Name	Disposable Spinal Anesthesia Needle
Needle point Type	Pencil Point
Package & delivery unit	Individually packed and 25 pcs/box E.O.G.sterilized (shelf life 5years)
Product Trade Name	UNIEVER SPINAL ANESTHESIA NEEDLE

■ Standard sizes

G：Gauge / Color Code	Length	Introducer	REF(Code No.)
22G	90mm	–	2120471
24G	90mm	–	2130571
25G	90mm	20G38mm	5290761
26G	90mm	20G38mm	5300661
27G	90mm	22G38mm	5310761
29G	90mm	22G38mm	5320261

*Please inquire at us for sizes out of the above table.

■ Unique opening shape and precise puncture resistance

Our original trapezoidal side hole is registered under #2112670 of the Practical New Ideas of the Japan Patent Office. This shape lets you securely feel the passage through the membrane and also helps achieve very rapid CSF flush back. The side hole located within
2mm from needle tip (except 22G) is efficient to prevent neuronyxis.

■ Puncture (K3 vs. pencil)

Pencil point needles cause puncture resistance that is up to three times greater than the resistance encountered by K-3 lancet point needles. This resistance affects the skin and tissues when the needle passes through. This is why it is recommended that an introducer is used with the non-cutting pencil point needle. On the other hand, the resistance may enable the anesthetist to perceive more distinctively the transit through the arachnoid mater, therefore decreasing the risk of nerve puncture.

■ Puncture cuts
（Cutting vs. non-cutting）

Several studies explain why a non-cutting point needle is less likely to cause PDPH. One of the theories is that the cutting point needle makes a sharp crescent-shaped cut in the arachnoid mater, while the non-cutting point needle makes an opening in the arachnoid mater comparable to a pushed-open clam shell. We have confirmed very similar opening shapes in an in-house experiment using polyamide films.
The sharp crescent-shaped cut took a long time to adhere while the blunt clam shell opening took less time to adhere, despite its large opening surface.

■ Successive images of
CSF leak simulation

Using a measuring cylinder as the spinal cord, red-colored water as CSF, and the polyethylene film as the arachnoid mater, we observed the water leak after needle puncture of the film.
The puncture was considered more invasive when more water leak was observed following removal of the needle.
The red water leak stopped more quickly with the non-cutting needle than with the cutting needle, suggesting a more prompt CSF leak control is possible with a non-cutting needle.

Noncutting needles encounter high puncture resistance due to their blunt tips. To prevent damage to tissues, it is recommended that an introducer be used to secure insertion of the non-cutting needle while decreasing tissue damage.
The introducer can also decrease the risk of needle breakage and help prevent erroneous insertion, especially for fine needles of 25G or less. However, if the introducer is not correctly inserted, the tip of pencil point needle may pass through the spinal canal.

The Greene needle was a noncutting point needle preceding the Whitacre needle. An American anesthetist, Rolland J. Whitacre, M.D., credited Greene’s advances in minimizing trauma to the dural fibers when he developed his innovative needle with conical tip, in collaboration with BD, and published it in 1951. Ever since, the shape and details of the needle have been constantly improved and refined, especially the shapes of the tip and the agent outlet.