Reactions 1434 - 12 Jan 2013

SMepivacaine

Motor paralysis, respiratory depression and varioustoxicities: 9 case reports

From a study of 613 patients undergoing spinal pain block,seven women and two men, aged 40–79 years, developedmotor paralysis, respiratory depression and various othertoxicities following administration of mepivacaine.

Five patients underwent medial branch blocks (MBB) withinjections of 2mL of mepivacaine 2% at three points, twopatients underwent transforaminal epidural blocks withinjections of 1mL of mepivacaine 2% at one and two points,respectively, one patient underwent a dorsal root ganglionblock with a 1mL injection of mepivacaine 1% at C2, and thefinal patient underwent an interlaminar epidural block with a1mL injection of mepivacaine 2%. Indications for spinal painblocks included herniated nucleus pulposus, ossification of theposterior longitudinal ligament, spinal stenosis, compressionfracture, spinal instability and cervicogenic headache.Neurological complications of spinal block included motorparalysis in eight of the patients, and respiratory depression inthree patients. Other symptoms included nausea, chestdiscomfort, hypotension, bradycardia and mydriasis[durations of treatments to reaction onsets not stated]. Thecauses of ADRs were a high concentration of mepivacaine infive of the patients, inadvertent vascular injection ofmepivacaine in three patients, and intrathecal leak ofmepivacaine in the remaining patient.

All of the patients symptoms recovered after 1–9 hours. Oneof the patients presented with impotence and fecalincontinence 1 week after discharge, which resolved over2 months with urologic treatment. Two of the patientsreceived a second MBB with 2mL of mepivacaine 2%, withrecurrence of paraplegia.

Author comment: "The probable causes of thesetemporary adverse effects were a high concentration ofmepivacaine in five patients, inadvertent vascular injection inthree patients [and] intrathecal leak of local anaesthetics inone [patient]".Lee H-I, et al. Transient adverse neurologic effects of spinal pain blocks. Journalof Korean Neurosurgical Society 52: 228-233, No. 3, 30 Sep 2012. Available from:URL: http://dx.doi.org/10.3340/jkns.2012.52.3.228 - South Korea 803082110

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Reactions 12 Jan 2013 No. 14340114-9954/10/1434-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved