Peripheral Nerve Injury due to Injection Needles used for Regional Anesthesia

Abstract

Nerve injury can arise as a complication peripheral nerve block anesthesia. Of the various factors involved, the trauma caused by the injection needle may be of significance. In this experimental study the frequency of fascicular injury was investigated immediately after needling isolated rabbit sciatic nerve preparations, and after intraneural injection with the nerve in situ. Two different injection needles were used, one with a bevel angle of 14 degrees and the other with a 45 degrees bevel angle. Fascicular injury was indicated by a fluorescence microscopy technique, tracing locally applied Evans Blue Albumin, The results show that a 45 degrees-beveled needle less frequently produces fascicular damage and should therefore be recommended for use in clinical anesthesia. It is also concluded that paresthesiae, when necessary, should be elicited gently, and that intraneural injections should be avoided.

Injection Injury of the Sciatic Nerve:Unusual Anatomic Distribution of Nerve Damage

“…A sciatic nerve injection injury may present in three ways: as immediate neuropa thy with instantaneous pain, immediate neu ropathy without instantaneous pain, or de layed paralysis [10,18,19], It was once believed that the injected chemical could dif fuse to the nerve from a distant, properly selected site [10], but this does not occur in cadaver studies [5,18,19], Animal studies indicate that intraneural injection is neces sary and mere perineural injection is insuffi cient to produce nerve damage [2,3,17], The type of chemical is also important [2,3,17], but mechanical trauma of the needle tip alone may cause damage to nerve fascicles [11,13], Needle trauma may produce typically local ized damage as can be seen in injuries occur ring during brachial plexus anesthesia [13].…”

Pathophysiology of Peripheral Nerve Injury During Regional Anesthesia

“…A fascicular injury is more likely to result from nerve contact with sharp-beveled needles than with a blunt-beveled needle, 36 but if penetration of a fascicle is achieved, a sharp-bevelled needle causes greater damage. 37 Needle-tip penetration of the nerve may not itself be the cause of clinical complications, 38 and no functional change is evident in humans after the passage of a needle into the ulnar nerve if local anesthetic is not injected intraneurally.…”

Evaluation of a new fenestrated needle for ultrasound-guided fascia iliaca block

“…Despite the effectiveness of these techniques, there is still not widespread application of lower extremity blocks among anesthesia providers [3]. Possible explanations for the limited use of these nerve blocks include concern about injury when using paresthesia or nerve stimulation techniques [7] or poor success rates when locating the FI using bloss of resistance.Q When a conventional needle is used, successful bthreein-oneQ block requires immediate proximity or actual contact of the injecting needle with the FN. The bfascia iliacaQ block, although not requiring contact with the nerve, depends on accurate placement of the needle bevel within a very thin fascial plane detected by loss of resistance to injection.…”