Intraneural and Perineural Inflammatory Changes in Piglets After Injection of Ultrasound Gel, Endotoxin, 0.9% NaCl, or Needle Insertion without Injection

Abstract

Perineural gel injections cause significant inflammation. The lack of cytokines suggests injectate-related changes rather than mechanical trauma.

Pathophysiology and Etiology of Nerve Injury Following Peripheral Nerve Blockade

“…Animal data suggest that ultrasound gel can lead to inflammation in the subarachnoidal space 47 and peripheral nerves. 48 …”

Comment on the safety of the ultrasound-guided hydrodissection technique for carpal tunnel syndrome

“…Thus, the ultrasound gel is delivered around or inside the nerves during regional anesthesia [1]. Pintaric et al [2] showed that perineural gel injections cause significant inflammation. This inflammation was not due to direct needle trauma, but rather, it was injectate/gelrelated.…”

“…This inflammation was not due to direct needle trauma, but rather, it was injectate/gelrelated. When using a sterile gel as the contact media for perineural injections, the gel carried by the needle further irritates the nerves and causes neurogenic inflammation [2]. For ultrasound-guided procedures, sterile gel is not used as the contact medium between the sheath and the skin.…”

Transversus Abdominis Plane Block: An Updated Review of Anatomy and Techniques

“…In other words, the probe is placed in the gravity-dependent part as a general rule below the needle insertion site for single-shot peripheral nerve blocks [ 65 , 66 ]. Jelly introduction into the central part of the body should be avoided whenever possible, even if it is aseptic [ 67 ], and ultrasound gel itself near peripheral nerves may cause inflammation [ 68 ]. Performing the dual TAP block in this sequence keeps the needle away from gravity-dependent gel contamination.…”