Anaesthesia, 2010, 65, pages 646–656 Correspondence . ....................................................................................................................................................................................................................
breaching the dura before the stylet removal. Our case highlights an unusual cause of presumed accidental dural puncture. The loss of resistance technique failed because a fat plug occluded the Tuohy needle. This problem may have been avoided by reinsertion of the stylet in the ligamentum flavum to check the patency of the lumen. B. Pearce A. Holtham University Hospital North, Durham, UK E-mail:
[email protected]
No external funding and no competing interests declared. Published with the patient’s written consent.
References 1 Gleeson CM, Reynolds F. Accidental dural puncture rates in UK obstetric practice. International Journal of Obstetric Anesthesia 1998; 7: 242–6. 2 Cohen S, Sakr A, Groysman R, Bhavsar V, Amar D. Does stylet reinsertion upon reaching ligamentum flavum with an epidural needle reduce the incidence of accidental dural puncture? Anesthesiology 2003; 99: A1161. doi: 10.1111/j.1365-2044.2010.06359.x
Sugammadex in patients with myasthenia gravis
Unterbuchner and colleagues [1] described in their case report the successful reversal of a rocuronium-induced neuromuscular block in a patient with myasthenia gravis. The authors suggest that more evidence is required to examine the use of sugammadex in patients with myasthenia gravis. We would like to report our experience with two patients (with mild generalised muscle weakness, class IIa in myasthenia gravis severity classification system by Osserman and Jenkins [2] and on chronic cholinesterase inhibitor medication) in which we reversed an intense rocuronium-induced neuromuscular block with sugammadex. Both patients were scheduled for short procedures and subsequently gave consent for publication.
After inducing neuromuscular block with rocuronium (0.15 mg.kg)1, which is 25% of the standard dose required for tracheal intubation in normal patients), both patients developed an intense neuromuscular block [3]. At the end of the surgical procedure, monitoring of the neuromuscular function (TOF-Watch SX; MSD ⁄ Shering-Plough Ireland Ltd, Dublin, Ireland) showed no response of the train-of-four and a post-tetanic count was 0. We then reversed the block with 4.0 mg.kg)1 sugammadex. The time from the administration of sugammadex to 90% recovery of the train-of-four ratio was 162 s for the first patient and 135 s for the second. No adverse changes were observed in arterial blood pressure, heart rate or ECG after the administration of sugammadex. The recovery of anaesthesia was uneventful and no signs of residual neuromuscular block or recurarisation were observed. Although there is controversy whether cholinesterase inhibitor medication should be continued until the time of the operation, if patients are reliant on their cholinesterase inhibitor medication it should probably be continued peri-operatively [4]. As sugammadex does not interfere with cholinergic homeostatic regulation, continuation of cholinesterase inhibitors pre-operatively does not affect the efficacy of the reversal of neuromuscular block by sugammadex and therefore optimal muscle function is preserved. Reversal of a rocuronium-induced neuromuscular block by sugammadex will eliminate the risk of residual neuromuscular blockade in these patients with their highly increased sensitivity to nondepolarizing neuromuscular blocking drugs. The combination of rocuronium and sugammadex may avoid the requirement for suxamethonium. Moreover, the use of sugammadex prevents the need for postoperative mechanical ventilation, often the consequence of using non-depolarizing neuromuscular blocking drugs. Reversal of rocuronium-induced intense neuromuscular block by sugammadex in our two patients with
2010 The Association of Anaesthetists of Great Britain and Ireland
myasthenia gravis was rapid, efficient, and without signs of postoperative residual neuromuscular block. We emphasise that in these two patients reversal of the neuromuscular block was initiated at a level of intense neuromuscular block, in contrast to the case described by Unterbuchner and colleagues. These additional cases contribute additional evidence that the combination of rocuronium and sugammadex for neuromuscular block and its reversal is safe and beneficial in myasthenia gravis. H. D. de Boer J. van Egmond J. J. Driessen L. H. J. D. Booij Martini General Hospital, Groningen, Netherlands Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands E-mail:
[email protected]
H.D. de Boer has received a lecture fee from MSD ⁄ Schering-Plough and L.H.D.J Booij was a member of the scientific advisory board of Organon (part of Schering-Plough).
References 1 Unterbuchner C, Fink H, Blobner M. The use of sugammadex in a patient with myasthenia gravis. Anaesthesia 2010; 65: 302–5. 2 Ossenman KE, Jenkens G. Studies on myasthenia gravis. Review of a twentyyear experience in over 1200 patients. The Mount Sinai Journal of Medicine 1971; 38: 497–537. 3 Fuchs-Buder T, Claudius C, Skovgaard LT, Eriksson LI, Mirakhur RK, VibyMogensen J. Good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents II: the Stockholm revision. Acta Anaesthesiologica Scandinavica 2007; 51: 789– 808. 4 Tripathi M, Kaushik S, Dubey P. The effect of the use of pyridostigmine and requirement of vecuronium in patients with myasthenia gravis. Journal of Postgraduate Medicine 2003; 49: 311–5. doi: 10.1111/j.1365-2044.2010.06360.x
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