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Mitochondial disorders and Anaesthesia
- Joshua Adedokun, [Kathryn Naylor] (23 April 2008)
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Joshua Adedokun, Consultant Anaesthetist North Manchester General Hosptial, Manchester, UK, [Kathryn Naylor]
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Editor, We read with interest the review article on mitochondrial disorders and general anaesthesia(1) and commend the authors on their succinct summary of the mitochondrial disorders and their anaesthetic management. We would very much welcome the development of evidence based clinical guidelines from the regional centres to assist in the anaesthetic management of this challenging and diverse group of patients as we were recently involved in managing a case at our district general hospital. A 68 year old lady presented for bilateral first metatarsal osteotomies. She had been diagnosed with mitochondrial cytopathy due to multiple DNA deletions in 1993 following a prolonged period of undiagnosed muscle weakness and visual problems. No further or more detailed diagnosis of her precise mitochondrial disorder has been made. The clinical presentation of her disease comprised peripheral neuropathy, proximal muscle weakness, chronic progressive opthalmoplegia, mild sensory and gait ataxia and chronic lower back pain. The patient had undergone a caesarean section in 1965 and a hysterectomy in 1989 both under general anaesthesia although no records were available at the time of her present procedure. Both procedures were complicated by post operative nausea and vomiting (PONV). An operation to correct bilateral ptosis was carried out in 2007 under local anaesthesia. Pre operative cardio respiratory examination was unremarkable. She had bilateral leg weakness which had been stable for several years. In common with the authors of the above study we found a review of the literature was primarily limited to case reports and small case series however we were concerned about the potential effects of anaesthetic agents on mitochondrial function (2) particularly as we had very limited information about the biochemical defect involved. Our patient wished to avoid general anaesthesia because of previous PONV and in view of the peripheral nature of the surgery, after gaining informed consent, we elected to carry out the procedure under spinal anaesthesia. The patient was nil by mouth for 6 hours prior to surgery and 0.9% saline infusion was commenced pre operatively. In the sitting position under full aseptic conditions a local anaesthetic of 2mls 2% lidocaine was injected at the level of L3/L4. A 24G sprotte needle was used to inject 2.5mls 0.5% heavy bupivacaine and 300microgrammes of diamorphine into the subarachnoid space at the level of L3/L4. The patient was then laid supine and a block to the level of T8 was achieved within 10 minutes. During the operation she was sedated with 2mg midazolam and a propofol target controlled infusion of between 0.5 and 1.0 microg/kg/min. Ondanestron 4mg was given as prophylaxis against PONV. The patient’s blood pressure remained stable throughout and no vasopressors were required. The procedure lasted 90 minutes and recovery was uneventful. The following day there was no residual effects from the spinal anaesthetic and the patient was discharged home. Previous case reports have documented the safe and effective use of spinal anaesthesia in patients with mitochondrial disease (3, 4). In view of the broad and variable nature of these conditions it is difficult to extrapolate this information to other subtypes of mitochondrial abnormalities. Concerns exist surrounding the use of local anaesthetic agents. These drugs have been shown to uncouple oxidative phosphorylation in mitochondria in a rat heart model but it is not known if this effect is seen in neurological tissue either with or without mitochondrial abnormalities (5). There are also issues surrounding the safety of spinal or epidural techniques in patients with lower limb neurological and muscular disease. Demyelination in the spinal cord in patients with mitochondrial encephalomyopathy has been reported and the use of spinal and epidural techniques under these circumstances is controversial(4). In our case intrathecal bupivacaine and diamorphine were both given to a patient with mitochondrial cytopathy and bilateral lower limb neuromuscular disease. No residual effects were seen after anaesthesia. In addition the patient was safely and effectively sedated using a combination of midazolam and propofol target controlled infusion with no detrimental effect on respiratory function. Spinal anaesthesia was chosen in this case as it removed the potential risk associated with volatile anaesthetic agents and neuromuscular blockade. In addition it can provide good post operative analgesia and reduce the increased oxygen demands associated with the stress response to surgery. However the recent review provides evidence that the risk from general anaesthesia at least in the paediatric population may not be as relevant clinically as previously thought. It is likely in the future that increasing numbers of patients will be diagnosed with these conditions and present to both paediatric and adult services. The development of evidence based guidelines would greatly assist anaesthetists with this diverse group of patients. K. Naylor J. Adedokun Joshua.Adedokun@pat.nhs.uk Manchester, UK 1. Footitt EJ, Sinha MD, Raiman JAJ, et al. Mitochondrial disorders and general anaesthesia: a case series and review. Br J Anaesth 2008; 100: 436-41. 2. Morgan P, Hoppel CL, Sedensky MM. Mitochondrial defects and anaesthetic sensitivity. Anaesthesiology 2002;96:1268-70 3. Hsiao PN, Cheung YJ, Tseng HC, et al. Spinal Anaesthesia in MELAS syndrome: A Case with Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis and Stroke Like Episodes. Acta Anaesthesiol Sin 2000;38 : 107-10. 4. Ohara S, Ohama E, Takahashi H, et al. Alterations of oligodendrocytes and demyelination in the spinal cord of patients with mitochondrial encephalomyopathy. Neurol Sci 1988 ;86 : 19-29. 5. Nouette-Gaulain K, Forestier F, Malgar M, et al. Effects of bupivacaine on mitochondrial energy metabolism in heart of rats following exposure to chronic hypoxia. Anaesthesiology 2002;97: 1507-11 Conflict of Interest:None declared |
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