Reactions 1335 - 22 Jan 2011

SDexamethasone/mepivacaine

Anaphylaxis: case reportA 29-year-old woman developed anaphylaxis during

epidural nerve block with dexamethasone and mepivacainefor low back pain.

The woman, whose history included four uncomplicatedsurgeries under general and epidural anaesthesia, wasscheduled to undergo L4-5 epidural block and lumbar facetblock as an outpatient. After confirmation of the epiduralspace, 0.5% mepivacaine 5mL and dexamethasone 4mgwere gradually injected into the epidural space. Shereported itchy eyes and a runny nose 15 minutes later, andsubsequently developed generalised pruritus. Examinationrevealed blood congestion of both eyelids, nasal discharge,flushing and multiple hives on her extremities and trunk.

Drug-induced anaphylactic shock was suspected, andthe woman started receiving Ringer’s lactate andmethylprednisolone 22 minutes later. She reported nauseaand abdominal pain after another 30 minutes. Her pulsewas faint, and BP unmeasurable. Treatment comprisedhigh-volume Ringer’s lactate, ephedrine, epinephrine[adrenaline], chlorphenamine, famotidine, mexiletine and adopamine infusion. Her systolic BP stabilised after2.5 hours, and her rash resolved. She was admitted to anICU. Her nausea resolved after 3 hours, but abdominal painand pruritus persisted. The following day, 16 hours afterthe epidural block, she reported breathing difficulties, andbegan receiving oxygen via a face mask. Dyspnoea resolvedon second day after the nerve block, but pruritus remained.Three days after the nerve block, a cardiac ultrasoundrevealed mildly reduced wall motion, and an ejectionfraction of 50%. At that time, she was receivingchlorphenamine, famotidine, and pulses of hydrocortisoneand prednisolone. Her symptoms improved, and she wasdischarged from the ICU 4 days after the intervention. Wallmotion had normalised on 1-month follow-up, and herejection fraction was 75%. Her serum histamine levels hadbeen elevated between 30 minutes and 11 hours postonset, while serum tryptase levels had remained normal.

Author comment: We think that the adverse event in thepresent case was non-immunological anaphylaxis caused bythe mepivacaine or dexamethasone used in the epiduralblock.Konishi R, et al. Anaphylactic reaction to epidural block in an outpatient. Masui.The Japanese Journal of Anesthesiology 59: 1287-1290, 10 Oct 2010 [Japanese;summarised from a translation.] - Japan 803048481

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Reactions 22 Jan 2011 No. 13350114-9954/10/1335-0001/$14.95 © 2010 Adis Data Information BV. All rights reserved