Continuous microspinal anaesthesia: another perspective on mechanisms inducing cauda equina syndrome

Abstract

SummaryContinuous spinal anaesthesia through a microspinal catheter technique has been criticised on several grounds and is now rarely used. This paper reviews the possible causes of the cauda equina syndrome which have been described and, on the basis of research in cadaver preparations, a glass 'spine' model and clinical experience in over 200 cases, suggests how these problems might be avoided. The use of careful insertion techniques, limiting the length of catheter inserted into the subarachnoid space and the use of no stronger than 0.5% bupivacaine solution are recommended.

Minimum effective local anaesthetic dose of isobaric levobupivacaine and ropivacaine administered via a spinal catheter for hip replacement surgery

“…Most published cases have been associated with the use of 5% lidocaine in hyperbaric (7.5%) dextrose. 18 Unfortunately, only a few prospective studies have formally investigated the real incidence of neurological complications. 19 At present we do not have sufficient proof that levobupivacaine or ropivacaine would be safer than lidocaine in this respect.…”

Is continuous spinal analgesia via an epidural catheter appropriate after accidental subarachnoid administration of 15 mL of bupivacaine 0.1% containing fentanyl 2 μg/mL?

“…9;10 Furthermore, from a study of 12 cadavers using videoscopy, it has been suggested that neurological damage in the clinical situation may also be caused by direct nerve damage on insertion of the spinal needle and also by formation of a loop of subarachnoid catheter that tightens on a nerve during its removal. 10 In summary, we have illustrated an important pitfall of supervising a junior trainee anaesthetist from a distance, i.e. an unrecognised dural puncture and the potential for causing a total spinal.…”

Raquianestesia contínua com altas doses de anestésicos locais

“…Since the set has a second orifice 5 mm from its tip, there is no need of introducing it more than 20 mm in the subarachnoid space. Preparations in cadavers for endoscopic studies demonstrated that all catheters introduced over 30 mm in the subarachnoid space developed loops 8 . When the catheter is removed, a loop could get entangled on a nerve root, causing direct trauma to the nerve by strangulation 8 .…”

“…Preparations in cadavers for endoscopic studies demonstrated that all catheters introduced over 30 mm in the subarachnoid space developed loops 8 . When the catheter is removed, a loop could get entangled on a nerve root, causing direct trauma to the nerve by strangulation 8 . In the present case, the catheter was introduced no more than 20 mm, enough for injections, without any problems upon its removal.…”