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Glahn KPE, Ellis FR, Halsall PJ, Müller CR, Snoeck MMJ, Urwyler A, Wappler F. Recognizing and managing a malignant hyperthermia crisis: guidelines from the European Malignant Hyperthermia Group. Br J Anaesth 2010; 105:417-20. [PMID: 20837722 DOI: 10.1093/bja/aeq243] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Survival from a malignant hyperthermia (MH) crisis is highly dependent on early recognition and prompt action. MH crises are very rare and an increasing use of total i.v. anaesthesia is likely to make it even rarer, leading to the potential risk of reduced awareness of MH. In addition, dantrolene, the cornerstone of successful MH treatment, is unavailable in large areas around the world thereby increasing the risk of MH fatalities in these areas. The European Malignant Hyperthermia Group collected and reviewed all guidelines available from the various MH centres in order to provide a consensus document. The guidelines consist of two textboxes: Box 1 on recognizing MH and Box 2 on the treatment of an MH crisis.
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Affiliation(s)
- K P E Glahn
- Danish Malignant Hyperthermia Centre, Department of Anaesthesia, University Hospital Herlev, Copenhagen, Denmark.
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Carpenter D, Robinson RL, Quinnell RJ, Ringrose C, Hogg M, Casson F, Booms P, Iles DE, Halsall PJ, Steele DS, Shaw MA, Hopkins PM. Genetic variation in RYR1 and malignant hyperthermia phenotypes. Br J Anaesth 2009; 103:538-48. [PMID: 19648156 DOI: 10.1093/bja/aep204] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Malignant hyperthermia (MH) is associated, in the majority of cases, with mutations in RYR1, the gene encoding the skeletal muscle ryanodine receptor. Our primary aim was to assess whether different RYR1 variants are associated with quantitative differences in MH phenotype. METHODS The degree of in vitro pharmacological muscle contracture response and the baseline serum creatine kinase (CK) concentration were used to generate a series of quantitative phenotypes for MH. We then undertook the most extensive RYR1 genotype-phenotype correlation in MH to date using 504 individuals from 204 MH families and 23 RYR1 variants. We also determined the association between a clinical phenotype and both the laboratory phenotype and RYR1 genotype. RESULTS We report a novel correlation between the degree of in vitro pharmacological muscle contracture responses and the onset time of the clinical MH response in index cases (P<0.05). There was also a significant correlation between baseline CK concentration and clinical onset time (P=0.039). The specific RYR1 variant was a significant determinant of the severity of each laboratory phenotype (P<0.0001). CONCLUSIONS The MH phenotype differs significantly with different RYR1 variants. Variants leading to more severe MH phenotype are distributed throughout the gene and tend to lie at relatively conserved sites in the protein. Differences in phenotype severity between RYR1 variants may explain the variability in clinical penetrance of MH during anaesthesia and why some variants have been associated with exercise-induced rhabdomyolysis and heat stroke. They may also inform a mutation screening strategy in cases of idiopathic hyperCKaemia.
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Affiliation(s)
- D Carpenter
- MH Investigation Unit, Academic Unit Anaesthesia, St James's University Hospital, Leeds LS9 7TF, UK
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Robinson RL, Carpenter D, Halsall PJ, Iles DE, Booms P, Steele D, Hopkins PM, Shaw MA. Epigenetic allele silencing and variable penetrance of malignant hyperthermia susceptibility. Br J Anaesth 2009; 103:220-5. [PMID: 19454545 DOI: 10.1093/bja/aep108] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Tissue-specific monoallelic silencing of the RYR1 gene has been proposed as an explanation for variable penetrance of dominant RYR1 mutations in malignant hyperthermia (MH). We examined the hypothesis that monoallelic silencing could explain the inheritance of an MH discordant phenotype in some instances. METHODS We analysed parent-offspring transmission data from MH kindreds to assess whether there was any deviation from the expected autosomal dominant Mendelian inheritance pattern. We also evaluated informative single-nucleotide polymorphism (SNP) genotypes in a cohort of unrelated MH patients using genomic DNA (gDNA, prepared from leucocytes) and coding DNA (cDNA, prepared from skeletal muscle). Finally, we examined the segregation of specific mutations at the gDNA and cDNA level within MH families where positive RYR1 gDNA genotype/normal MH phenotype discordance had been observed. RESULTS In 2113 transmissions from affected parents, there was a consistent parent-of-origin effect (P<0.001) with affected fathers having fewer affected daughters (20%, 95% CI 17-22%) than affected sons (25%, 95% CI 23-26%) or unaffected daughters (27%, 95% CI 25-30%). No discrepancies were observed between the RYR1 SNP genotypes recorded at the gDNA and cDNA levels. In 14 MH negative individuals from 11 discordant families, the familial mutation was detected in skeletal muscle cDNA in all cases. CONCLUSIONS Epigenetic allele silencing may play a role in the inheritance of MH susceptibility, but this is unlikely to involve silencing of RYR1.
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Affiliation(s)
- R L Robinson
- MH Investigation Unit, Academic Unit of Anaesthesia, St James's University Hospital, Leeds LS9 7TF, UK
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Carpenter D, Morris A, Robinson RL, Booms P, Iles D, Halsall PJ, Steele D, Hopkins PM, Shaw MA. Analysis ofRYR1Haplotype Profile in Patients with Malignant Hyperthermia. Ann Hum Genet 2009; 73:10-8. [DOI: 10.1111/j.1469-1809.2008.00482.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Duke AM, Hopkins PM, Halsall PJ, Steele DS. Mg2+ dependence of Ca2+ release from the sarcoplasmic reticulum induced by sevoflurane or halothane in skeletal muscle from humans susceptible to malignant hyperthermia. Br J Anaesth 2006; 97:320-8. [PMID: 16849381 DOI: 10.1093/bja/ael179] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND In normal resting muscle, cytosolic Mg(2+) exerts a potent inhibitory influence on the sarcoplasmic reticulum (SR) Ca(2+) release channel (ryanodine receptor, RyR1). Impaired Mg(2+)-regulation of RyR1 has been proposed as a causal factor in malignant hyperthermia (MH). The aim of this study was to compare the effects of cytosolic Mg(2+) on SR Ca(2+) release induced by halothane or sevoflurane in normal (MHN) and MH susceptible (MHS) human skeletal muscle fibres. METHODS Samples of vastus medialis muscle were obtained from patients under investigation for MH susceptibility. Single fibres were mechanically skinned and perfused with solutions mimicking the intracellular milieu. Changes in [Ca(2+)](i) were detected using fura-2 fluorescence after application of equimolar halothane or sevoflurane. RESULTS In MHN fibres, concentrations of sevoflurane or halothane as high as 10 mM typically failed to induce SR Ca(2+) release at physiological free [Mg(2+)] (1 mM). However, when [Mg(2+)] was decreased to 0.4 mM, SR Ca(2+) release occurred in 51% (16/33) and 6% (2/33) of MHN fibres after the addition of 1 mM halothane or 1 mM sevoflurane, respectively. Further decreases in [Mg(2+)] increased the proportion of responsive fibres. In the presence of 0.1 mM [Mg(2+)], Ca(2+) release occurred in all fibres (33/33) after the introduction of 1 mM halothane or 1 mM sevoflurane. In MHS fibres, 1 mM halothane or 1 mM sevoflurane-induced Ca(2+) release in 54% (7/13) or 15% (2/13) of fibres, respectively, at 1 mM Mg(2+). A decrease in [Mg(2+)] to 0.2 mM Mg(2+) was sufficient to render 100% of MHS fibres (13/13) responsive to 1 mM halothane or 1 mM sevoflurane. CONCLUSIONS In both MHS and MHN fibres (i) halothane is a more potent activator of SR Ca(2+) release than sevoflurane and (ii) as with halothane, the efficacy of sevoflurane-induced SR Ca(2+) release exhibits a marked dependence on cytosolic [Mg(2+)]. The marked potentiation of SR Ca(2+) release after a moderate reduction in cytosolic [Mg(2+)] suggests that conditions which cause hypomagnesaemia will increase the probability and possibly severity of an MH event. Conversely, maintenance of a normal or slightly increased cytosolic [Mg(2+)] may reduce the probability of MH.
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Affiliation(s)
- A M Duke
- Institute of Membrane and Systems Biology, University of Leeds Woodhouse Lane, Leeds LS2 9JT, UK
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Johi RR, Mills R, Halsall PJ, Hopkins PM. Anaesthetic management of coronary artery bypass grafting in a patient with central core disease and susceptibility to malignant hyperthermia on statin therapy. Br J Anaesth 2003; 91:744-7. [PMID: 14570802 DOI: 10.1093/bja/aeg262] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Central core disease and malignant hyperthermia (MH) are both associated with mutations in the RYR1 gene. We report the anaesthetic management of one such patient presenting for coronary artery bypass grafting. Her medication included aspirin 75 mg, atorvastatin 20 mg, isosorbide mononitrate 60 mg, atenolol 25 mg and glyceryl trinitrite sublingual spray as required. The use of aprotinin, statins and moderate hypothermia in patients with central core disease and known susceptibility to MH has not been documented.
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Affiliation(s)
- R R Johi
- Department of Anaesthesia, William Harvey Hospital, Kennington Road, Ashford, Kent TN23 3AQ, UK.
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Wappler F, Anetseder M, Baur CP, Censier K, Doetsch S, Felleiter P, Fiege M, Fricker R, Halsall PJ, Hartung E, Heffron JJA, Heytens L, Hopkins PM, Klingler W, Lehmann-Horn F, Nivoche Y, Tegazzin V, Tzanova I, Urwyler A, Weisshorn R, Schulte am Esch J. Multicentre evaluation of in vitro contracture testing with bolus administration of 4-chloro-m-cresol for diagnosis of malignant hyperthermia susceptibility. Eur J Anaesthesiol 2003; 20:528-36. [PMID: 12884985 DOI: 10.1017/s026502150300084x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND AND OBJECTIVE The in vitro contracture test with halothane and caffeine is the gold standard for the diagnosis of susceptibility to malignant hyperthermia (MH). However, the sensitivity of the in vitro contracture test is between 97 and 99% and its specificity is 78-94% with the consequence that false-negative as well as false-positive test results are possible. 4-Chloro-m-cresol is potentially a more specific test drug for the in vitro contracture test than halothane or caffeine. This multicentre study was designed to investigate whether an in vitro contracture test with bolus administration of 4-chloro-m-cresol can improve the accuracy of the diagnosis of susceptibility to MH. METHODS Three hundred and fifty-two patients from 11 European MH laboratories participated in the study. The patients were first classified as MH susceptible, MH normal or MH equivocal by the in vitro contracture test according to the European MH protocol. Muscle specimens surplus to diagnostic requirements were used in this study (MH susceptible = 103 viable samples; MH equivocal = 51; MH normal = 204). 4-Chloro-m-cresol was added to achieve a concentration of 75 micromol L(-1) in the tissue bath. The in vitro effects on contracture development and muscle twitch were observed for 60 min. RESULTS After bolus administration of 4-chloro-m-cresol, 75 micromol L(-1), 99 of 103 MH-susceptible specimens developed marked muscle contractures. In contrast, only two of 204 MH-normal specimens showed an insignificant contracture development following 4-chloro-m-cresol. From these results, a sensitivity rate of 96.1% and a specificity rate of 99.0% can be calculated for the in vitro contracture test with bolus administration of 4-chloro-m-cresol 75 micromol L(-1). Forty-three patients were diagnosed as MH equivocal, but only specimens from 16 patients developed contractures in response to 4-chloro-m-cresol, indicating susceptibility to MH. CONCLUSIONS The in vitro contracture test with halothane and caffeine is well standardized in the European and North American test protocols. However, this conventional test method is associated with the risk of false test results. Therefore, an improvement in the diagnosis of MH is needed. Regarding the results from this multicentre study, the use of 4-chloro-m-cresol could increase the reliability of in vitro contracture testing.
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Affiliation(s)
- F Wappler
- University Hospital Hamburg-Eppendorf, Department of Anaesthesiology, Hamburg, Germany.
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Urwyler A, Halsall PJ, Mueller C, Robinson R. Ryanodine receptor gene (RYR1) mutations for diagnosing susceptibility to malignant hyperthermia. Acta Anaesthesiol Scand 2003; 47:492; author reply 493. [PMID: 12694155 DOI: 10.1034/j.1399-6576.2003.t01-2-00044.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
BACKGROUND Malignant hyperthermia (MH) is an inherited, potentially fatal, pharmocogenetic disorder triggered by certain anaesthetic agents. In light of the reported genetic heterogeneity for the disorder and the recent introduction of DNA testing guidelines for the trait, we have assessed the role of the CACNA1S gene in MH susceptibility in UK patients. Linkage to this locus has previously been demonstrated in several European MH families. METHODS AND RESULTS We screened 200 unrelated MH-susceptible individuals for known CACNA1S mutations. With the aim to characterize further novel mutations at this locus, functionally relevant regions of the gene were also sequenced in 10 unrelated individuals from families where the involvement of other MH susceptibility loci was unlikely. No sequence variations were detected in any of the patients investigated. CONCLUSIONS Defects in CACNA1S are not a major cause of MH in the UK population. Diagnostic screening of this gene is unlikely to be of value to UK MH patients in the near future.
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Affiliation(s)
- C Brooks
- MH Investigation Unit, St James' University Hospital, Leeds, UK
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Robinson RL, Curran JL, Ellis FR, Halsall PJ, Hall WJ, Hopkins PM, Iles DE, West SP, Shaw MA. Multiple interacting gene products may influence susceptibility to malignant hyperthermia. Ann Hum Genet 2000; 64:307-20. [PMID: 11415515 DOI: 10.1017/s0003480000008186] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2000] [Indexed: 11/06/2022]
Abstract
Malignant hyperthermia (MH) is a potentially lethal disorder triggered in susceptible individuals on exposure to common anaesthetic agents. Crises reflect the consequences of disturbed skeletal muscle calcium homeostasis. MH is an autosomal dominant, genetically heterogeneous trait. Defects in a single major gene have been assumed to determine susceptibility status in individual families. However, in some pedigrees phenotypic and genotypic data are discordant. One explanation, in contrast to the current genetic model, is that susceptibility is dependent upon the effects of more than one gene. Using the transmission disequilibrium test we assessed the involvement of 8 MH candidate loci (RYR1, CACNA1S, CACNA2D1, MHS4 at 3q13.1, MHS6 at 5p, LIPE, DM1, dystrophin) by analysis of data from 130 MH nuclear families. Results suggested that variations in more than one gene may influence MH susceptibility in single families.
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Curran JL, Hall WJ, Halsall PJ, Hopkins PM, Iles DE, Markham AF, McCall SH, Robinson RL, West SP, Bridges LR, Ellis FR. Segregation of malignant hyperthermia, central core disease and chromosome 19 markers. Br J Anaesth 1999; 83:217-22. [PMID: 10618932 DOI: 10.1093/bja/83.2.217] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Malignant hyperthermia (MH) is an autosomal dominant disorder presenting under general anaesthesia. It is occasionally associated with a myopathy, central core disease (CCD), named after its predominant histochemical characteristic. The penetration of CCD is variable, but typically affected individuals show delayed motor milestones in infancy and remain physically compromised. It was thought until recently that individuals with CCD were always susceptible to MH. Individuals from eight CCD families were screened for the presence of 13 mutations in the skeletal muscle ryanodine receptor gene, reported previously to be associated with MH and/or CCD: none was detected. In seven of these families, where CCD and MH co-existed, we examined the segregation of CCD, MH susceptibility and chromosome 19q markers. In four families, there was complete co-segregation between MH, CCD and the chromosome 19 markers, but in one large pedigree there was a clear lack of segregation of CCD with either MH or chromosome 19 markers and there was no segregation between MH and these markers. This is unequivocal evidence that CCD, in common with MH, is genetically heterogeneous. In the two other families, CCD segregated with chromosome 19 markers but not all individuals with CCD were susceptible to MH. We recommend determination of MH susceptibility in all patients with CCD, irrespective of the MH status of their relatives with CCD.
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Affiliation(s)
- J L Curran
- Malignant Hyperthermia Investigation Unit, University of Leeds, St James's University Hospital, UK
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Robinson R, Curran JL, Hall WJ, Halsall PJ, Hopkins PM, Markham AF, Stewart AD, West SP, Ellis FR. Genetic heterogeneity and HOMOG analysis in British malignant hyperthermia families. J Med Genet 1998; 35:196-201. [PMID: 9541102 PMCID: PMC1051241 DOI: 10.1136/jmg.35.3.196] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Malignant hyperthermia (MH) is an autosomal dominant genetic condition that presents in susceptible people undergoing general anaesthesia. The clinical disorder is a major cause of anaesthetic morbidity and mortality. The UK Malignant Hyperthermia Group has performed genetic linkage analysis on 20 large, well defined malignant hyperthermia families, using hypervariable markers on chromosome 19q13.1, including the candidate MH gene RYR1, the gene coding for the skeletal muscle ryanodine receptor protein. The results were analysed using LINKAGE to perform two point and multipoint lod scores, then HOMOG to calculate levels of heterogeneity. The results clearly showed genetic heterogeneity between MH families; nine of the families gave results entirely consistent with linkage to the region around RYR1 while the same region was clearly excluded in three families. In the remaining eight MHS families there were single recombinant events between RYR1 and MH susceptibility. HOMOG analysis was of little added benefit in determining the likelihood of linkage to RYR1 in these families. This confirmation of the presence of heterogeneity in the UK MH population, along with the possibility of the presence of two MH genes in some pedigrees, indicates that it would be premature and potentially dangerous to offer diagnosis of MH by DNA based methods at this time.
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Affiliation(s)
- R Robinson
- Department of Genetics, The University, Leeds, UK
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Ording H, Brancadoro V, Cozzolino S, Ellis FR, Glauber V, Gonano EF, Halsall PJ, Hartung E, Heffron JJ, Heytens L, Kozak-Ribbens G, Kress H, Krivosic-Horber R, Lehmann-Horn F, Mortier W, Nivoche Y, Ranklev-Twetman E, Sigurdsson S, Snoeck M, Stieglitz P, Tegazzin V, Urwyler A, Wappler F. In vitro contracture test for diagnosis of malignant hyperthermia following the protocol of the European MH Group: results of testing patients surviving fulminant MH and unrelated low-risk subjects. The European Malignant Hyperthermia Group. Acta Anaesthesiol Scand 1997; 41:955-66. [PMID: 9311391 DOI: 10.1111/j.1399-6576.1997.tb04820.x] [Citation(s) in RCA: 215] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Determination of sensitivity and specificity of the in vitro contracture test (IVCT) for malignant hyperthermia (MH) susceptibility using the European MH Group (EMHG) protocol has been performed in some laboratories but only on a small sample from the combined EMHG. Thus, the purpose of the present study was to determine combined EMHG sensitivity and specificity of the test. METHODS Results of IVCT of patients with previous fulminant MH and normal, low-risk subjects (controls) were collected from 22 centres of the EMHG. IVCT was performed according to the EMHG protocol. Patients were included in the study if the clinical crisis had a score of at least 50 points with the Clinical Grading Scale. Low-risk subjects were included provided they did not belong to a family with known MH susceptibility, they had not developed any signs of MH at previous anaesthetics, and they did not suffer from any neuromuscular disease. For inclusion of both MH patients and low-risk subjects, at least 1 muscle bundle in the IVCT should have twitches of 10 mN (1 g) or more. For evaluation of individual tests, only muscle bundles with twitch heights of 10 mN (1 g) or more were used. RESULTS A total of 1502 probands had undergone IVCT because of a previous anaesthesia with symptoms and signs suggestive of MH. Of these, 119 had clinical scores of 50 and above. From these 119 MH-suspected patients and from 202 low-risk subjects, IVCT data were collected. Subsequently, 14 MH-suspected patients were excluded from further analysis for the following reasons: In 3 patients, the suspected MH episode could be fully explained by diseases other than MH; in 11 MHS patients, IVCT was incomplete (n = 1), data were lost (n = 3), or none of the muscle bundles fulfilled twitch criteria (n = 7). Of the remaining 105 MH-suspected patients, 89 were MHS, 10 MHEh, 5 MHEc, and one MHN. Thus, we observed a diagnostic sensitivity of the IVCT of 99.0% if the MHE group is considered susceptible (95% confidence interval 94.8-100.0%). Of the 202 low-risk subjects, 3 were MHS, 5 MHEh, 5 MHEc, and 189 MHN. This gives a specificity of the IVCT of 93.6% (95% confidence interval 89.2-96.5%). CONCLUSION The IVCT for diagnosis of MH susceptibility in Europe has a high sensitivity and a satisfactory specificity.
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Affiliation(s)
- H Ording
- Academic Unit of Anaesthesia, University of Leeds, St. James's University Hospital, UK
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Adeokun AM, West SP, Ellis FR, Halsall PJ, Hopkins PM, Foroughmand AM, Iles DE, Robinson RL, Stewart AD, Curran JL. The G1021A substitution in the RYR1 gene does not cosegregate with malignant hyperthermia susceptibility in a British pedigree. Am J Hum Genet 1997; 60:833-41. [PMID: 9106529 PMCID: PMC1712455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A single base change in the RYR1 gene encoding the skeletal muscle ryanodine receptor (calcium-sensitive calcium-release channel of the sarcoplasmic reticulum), resulting in the substitution of G1021 by A, has been proposed to underlie malignant-hyperthermia (MH) susceptibility in as many as 10% of cases in the European population. As part of our mutation-screening program in MH-susceptible (MHS) individuals, we have investigated this substitution in individuals from 151 unrelated British MHS families and have detected G1021A heterozygotes in 7 families. This mutation was not found in 156 unrelated MH-negative (MHN) individuals. We also examined eight families with central core disease (CCD): the mutation did not occur in any family members of any disease status (affected or unaffected for CCD, MHS, or MHN). In one large family, the G1021A mutation was found but did not show complete cosegregation with MH susceptibility: it occurred in only 7/12 MHS individuals in the kinship, and susceptibility was inherited from parents who were G1021 homozygotes, as well as from parents who were heterozygotes. On the basis of these findings, it is clearly unreliable at present to offer presymptomatic DNA testing for MH status, even in families in which a mutation has been detected.
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Affiliation(s)
- A M Adeokun
- Department of Human Genetics, University of Newcastle upon Tyne, United Kingdom
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Hopkins PM, Ellis FR, Halsall PJ, Stewart AD. An analysis of the predictive probability of the in vitro contracture test for determining susceptibility to malignant hyperthermia. Anesth Analg 1997; 84:648-56. [PMID: 9052318 DOI: 10.1097/00000539-199703000-00034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An objective estimate of the likelihood of correct designation of malignant hyperthermia (MH) susceptibility from in vitro contracture test (IVCT) results is essential if genetic linkage studies of MH are to be more informative. The aim of this study was to generate and test statistical models that could be used to predict the probability of susceptibility of an individual to MH from the results of their IVCTs. Logistic regression of the IVCT results of an index group of 50 patients (age range 9-73 years; MH susceptible [MHS], n = 13; MH normal [MHN], n = 32; MH equivocal [MHE], n = 5) who were either at low risk of MH or were proband cases were used to generate models to predict probability of MH susceptibility. Models incorporated data from individual contracture tests or from combinations of tests (static halothane, dynamic halothane, caffeine, ryanodine) performed according to the protocols of the European Malignant Hyperthermia Group. Of the individual contracture tests, the ryanodine test was most closely correlated with MH status. Discriminatory ability of the models was assessed using receiver operating characteristic (ROC) curves. Inclusion of predictor variables from the ryanodine, caffeine, and dynamic halothane tests improved upon the discriminatory ability of the models incorporating variables from individuals tests and was considered to be the best model. The reproducibility of this model was confirmed using an ROC curve constructed using data from 47 patients (age range 10-62 years; MHS, n = 15; MHN, n = 28; MHE, n = 4) who were classified in a way similar to the index group. A further group of 153 patients (age range 9-74 years; MHS, n = 44; MHN, n = 92; MHE, n = 17) who were consecutively tested relatives of susceptible individuals was used to assess the generalizability of the best model. The model met the criteria for a useful discriminatory model with this group of patients, 125 of whom (including 9 MHE patients) could be designated as positive or negative for MH with a likelihood of more than 95%. The logistic regression models provide objective likelihoods for the MH phenotype that could be usefully incorporated into genetic linkage studies of the condition.
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Affiliation(s)
- P M Hopkins
- Malignant Hyperthermia Investigation Unit, Academic Unit of Anesthesia, St. James's University Hospital, Leeds, United Kingdom
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Abstract
1. Inhibition of sodium-calcium exchange using 100 microM benzamil caused contracture development of in vitro skeletal muscle samples from humans susceptible to malignant hyperthermia, but not of samples from normal individuals. 2. This dose of benzamil increased the contracture response of both types of muscle to halothane. 3. At a concentration of 1 microM, benzamil significantly reduced the contracture response to halothane of muscle from malignant hyperthermia individuals. 4. The implications for the role of sodium-calcium exchange in skeletal muscle calcium homeostasis and the pathophysiology of malignant hyperthermia are discussed.
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Affiliation(s)
- P M Hopkins
- Malignant Hyperthermia Investigation Unit, St James's University Hospital, Leeds, England
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Iles DE, Segers B, Sengers RC, Monsieurs K, Heytens L, Halsall PJ, Hopkins PM, Ellis FR, Hall-Curran JL, Stewart AD. Genetic mapping of the beta 1- and gamma-subunits of the human skeletal muscle L-type voltage-dependent calcium channel on chromosome 17q and exclusion as candidate genes for malignant hyperthermia susceptibility. Hum Mol Genet 1993; 2:863-8. [PMID: 8395940 DOI: 10.1093/hmg/2.7.863] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Malignant hyperthermia susceptibility (MHS) is an autosomal dominant disorder of skeletal muscle which manifests as a life-threatening hypermetabolic crisis triggered by commonly-used inhalation anaesthetics and depolarizing muscle relaxants. Defects in the ryanodine receptor (RYR1) protein have been proposed to underly MHS, but significant genetic heterogeneity in MHS has recently been demonstrated. In order to investigate the potential roles played by other skeletal muscle calcium channels in MHS, we isolated cosmids containing the gene encoding the beta 1-subunit of skeletal muscle L-type voltage-dependent calcium channel (CACNLB1). We identified a new, highly polymorphic dinucleotide repeat motif close to this gene, and linkage analysis placed the marker proximal to the HOX2B locus, previously localized to chromosome segment 17q21-q22. We recently identified a novel marker within the gamma-subunit locus (CACNLG) at band 17q24, and since both markers are within the 17q11.2-q24 region reported to contain the MHS2 locus, we tested them for linkage in MHS families whose disease trait has been shown not to co-segregate with markers for the RYR1 region on chromosome 19q13.1. Our results exclude CACNLB1 and CACNLG as candidate genes for MHS2, and do not support the reported chromosome 17q localization for the MHS2 locus in our families.
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Affiliation(s)
- D E Iles
- Department of Cell Biology and Histology, Faculty of Medical Sciences, Catholic University of Nijmegen, The Netherlands
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23
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Hopkins PM, Ellis FR, Halsall PJ. Comparison of in vitro contracture testing with ryanodine, halothane and caffeine in malignant hyperthermia and other neuromuscular disorders. Br J Anaesth 1993; 70:397-401. [PMID: 8499197 DOI: 10.1093/bja/70.4.397] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
In vitro exposure of living skeletal muscle to ryanodine has been proposed as a potentially specific test for malignant hyperthermia (MH). In this study we have compared in vitro contracture responses to halothane, caffeine and ryanodine in skeletal muscle specimens obtained from 155 patients attending for diagnosis of susceptibility of MH and also from six patients having muscle biopsy for diagnosis of other neuromuscular disorders. Although the ryanodine contracture test was not specific for MH, the results suggest it may greatly aid (in conjunction with the standard halothane and caffeine contracture tests) the accurate phenotyping of individuals that is essential for the further genetic analysis of MH.
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Affiliation(s)
- P M Hopkins
- University Department of Clinical Medicine (Anaesthesia), St James's University Hospital, Leeds
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24
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Ball SP, Dorkins HR, Ellis FR, Hall JL, Halsall PJ, Hopkins PM, Mueller RF, Stewart AD. Genetic linkage analysis of chromosome 19 markers in malignant hyperthermia. Br J Anaesth 1993; 70:70-5. [PMID: 8431338 DOI: 10.1093/bja/70.1.70] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Previous studies have reported that malignant hyperthermia susceptibility is caused in some families by inherited variation in a gene located on the short arm of chromosome 19 near to, or identical with, the ryanodine receptor gene (RYR1); this is expressed in skeletal muscle as a calcium release channel of the sarcoplasm reticulum. In other families, a gene in this location is excluded, but the locations of the genes involved have not yet been defined. We have analysed DNA samples from members of three large British families in whom in vitro muscle contracture tests for malignant hyperthermia susceptibility have been carried out in accordance with the procedure recommended by the European Malignant Hyperthermia Group. The results presented here strongly suggest that the gene for malignant hyperthermia susceptibility in one or more of these three British families is located in the same region of chromosome 19q, although further work is required to decide whether or not the RYR1 gene itself is causative in these families. As genetic heterogeneity could not be excluded, we cannot yet recommend the use of DNA markers to replace in vitro contracture tests in the diagnosis of malignant hyperthermia susceptibility.
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Affiliation(s)
- S P Ball
- Washington Singer Laboratories, School of Biological Sciences, University of Exeter
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25
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Abstract
A 34-year-old female patient developed methaemoglobinaemia following a femoral nerve block using prilocaine. The concentrations of methaemoglobin in the blood of the next eight patients receiving this block were assayed, and found to be significantly increased above baseline concentrations, but very significantly less than the concentration in the patient with symptomatic methaemoglobinaemia. Pulse oximetry was of value in making the diagnosis.
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Affiliation(s)
- M C Bellamy
- Academic Unit of Anaesthesia, St. James's University Hospital, Leeds
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26
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Abstract
The "K-type" designation is used to describe a patient being investigated for malignant hyperthermia (MH) when concurrent administration of caffeine and halothane induces muscle contracture (rigidity, spasm) in vitro, but when halothane and caffeine given separately produce a normal response. It is accepted in some centres that K-type individuals are susceptible to malignant hyperthermia (MHS). In this paper, the K-type is shown not to correlate with the MH susceptible (MHS) status as accepted by the European MH group.
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Affiliation(s)
- F R Ellis
- Leeds Malignant Hyperthermia Investigation Unit, St James's University Hospital, Leeds
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27
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Halsall PJ, Ellis FR, Knowles PF. Evaluation of spin resonance spectroscopy of red blood cell membranes to detect malignant hyperthermia susceptibility. Br J Anaesth 1992; 69:471-3. [PMID: 1334685 DOI: 10.1093/bja/69.5.471] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We have evaluated a spin labelled electron spin resonance technique to identify malignant hyperthermia susceptible (MHS) patients. We studied 19 patients, 10 MHS and nine MHN (normal), using the standard European procedure. We were unable to obtain any evidence that this technique could be used to diagnose MH susceptibility. Furthermore, there was no significant difference in the fluidity of the red blood cell membranes between the two groups, which would have been indicative of a generalized membrane abnormality in MH.
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Affiliation(s)
- P J Halsall
- Leeds MH Investigation Unit, University Department of Anaesthesia, St James's University Hospital
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28
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29
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30
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31
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Abstract
We are frequently asked if patients, in whom only postoperative pyrexia has been observed, should be considered as potentially susceptible to malignant hyperthermia (MHS). Of 30 patients of this type studied in this Unit, none was shown to be MHS. We consider that postoperative pyrexia alone is unlikely to signify MH.
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Affiliation(s)
- P J Halsall
- Leeds MH Investigation Unit, St James's University Hospital
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32
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Abstract
Malignant hyperthermia may be a human stress syndrome, of which heat stroke is one manifestation. Two men in military service who had episodes of exertional heat stroke, and their immediate family members, were tested for susceptibility to malignant hyperthermia by in-vitro contracture tests on skeletal muscle samples. Muscle from both patients had a normal response to caffeine but an abnormal response to halothane. Muscle from the father of one patient had an abnormal response to halothane, and that from the father of the second patient had an abnormal response to ryanodine. The results indicate that clinical heat stroke may be associated with an underlying inherited abnormality of skeletal muscle that is similar, but not identical, to that of malignant hyperthermia.
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Affiliation(s)
- P M Hopkins
- University Department of Clinical Medicine, St James's University Hospital, Leeds, UK
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33
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Abstract
In vitro contracture tests used currently for malignant hyperthermia (MH) do not possess absolute specificity. This is potentially a great problem in the study of the genetic approach which offers the best prospect for the development of a non-invasive diagnostic test for the condition. The calcium release channel of the sarcoplasmic reticulum has been proposed as the site of the MH defect. Ryanodine, which binds avidly to this channel, was shown to differentiate between muscle of MH susceptible and normal patients in terms of in vitro contracture response. This ryanodine contracture response is proposed as a potentially specific in vitro diagnostic test for MH.
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Affiliation(s)
- P M Hopkins
- University Department of Anaesthesia, St James's University Hospital, Leeds
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34
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Abstract
Two patients who developed hypermetabolic reactions during anaesthesia and surgery and who were suffering from arthrogryposis multiplex congenita are reported and it is proposed that the reaction is distinct from malignant hyperthermia and independent of the anaesthetic agents used. The implications for anaesthetists involved in the management of patients with arthrogryposis multiplex congenita are discussed.
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Affiliation(s)
- P M Hopkins
- University Department of Anaesthesia, St James's University Hospital, Leeds
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35
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Abstract
An assessment of local anaesthetic blockade of the lateral femoral cutaneous nerve using a standard technique was made. The rate of successful blockade was high, but the area of sensory loss was inconsistent between patients and was more anterior and distal than described in textbooks of anatomy.
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Affiliation(s)
- P M Hopkins
- University Department of Anaesthesia, St. James's University Hospital, Leeds
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36
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Abstract
As anaesthetists have become more aware of malignant hyperthermia the mortality rate has fallen, but concommitantly the number of dubious and aborted cases has increased. All probands who developed a suspected malignant hyperthermia reaction during anaesthesia and subsequently underwent muscle biopsy were classified according to the clinical presentation. A probability for malignant hyperthermia can be calculated, using the classification, for each type of clinical presentation; this varied from 0.96 to 0.07. Certain clinical features were found to be of more value as predictors than others; these included a high creative kinase and myoglobinuria. The accuracy of prediction depends on a clear contemporaneous description of the clinical events.
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Affiliation(s)
- F R Ellis
- University Department of Anaesthesia, St. James's University Hospital, Leeds
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37
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Abstract
Muscle relaxation rate following a tetanic stimulus of adductor pollicis muscle was measured prospectively in 26 patients potentially susceptible to malignant hyperthermia (MH) the day before a muscle biopsy was obtained for MH in vitro screening. Eleven subjects were found to be MH susceptible (MHS) and 15 subjects MH-negative (MHN). In all patients, relaxation rate was recorded at three different temperatures of the skin overlying adductor pollicis (30, 34 and 38 degrees C) achieved by a small surface heating unit placed over the thenar eminence. The MHS group exhibited slightly higher relaxation rate at 34 and 38 degrees C compared with the MHN group and this difference was accentuated with increasing temperature, but was not statistically different. The results of the present study suggest that relaxation rates are normal in MHS individuals under physiological conditions and cannot be used diagnostically for MH screening.
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Affiliation(s)
- A Urwyler
- University Department of Anaesthesia, St. James's University Hospital, Leeds
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38
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Ellis FR, Halsall PJ. Beta adrenergic blockade masks a malignant hyperthermia reaction. Anaesthesia 1989. [DOI: 10.1111/j.1365-2044.1989.tb09209.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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39
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Simpson KH, Halsall PJ, Sides CA, Keeler JF. Pain on injection of methohexitone. The use of lignocaine to modify pain on injection of methohexitone during anaesthesia for electroconvulsive therapy. Anaesthesia 1989; 44:688-9. [PMID: 2782576 DOI: 10.1111/j.1365-2044.1989.tb13597.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The present study was designed to assess the incidence of pain when methohexitone was administered to 35 depressed patients who had electroconvulsive therapy, and to determine whether the use of lignocaine could modify this, without affecting seizure duration. The same patients were studied during three separate treatment sessions; they received either methohexitone alone or mixed with, or preceded by, lignocaine 10 mg. Six (17%) patients spontaneously complained of pain during injection of methohexitone alone; the use of lignocaine prior to methohexitone reduced this to zero (p less than 0.05). A total of 49% patients reported pain during injection of methohexitone; the use of lignocaine either mixed with, or given prior to, methohexitone significantly reduced this to 23% and 20% respectively (p less than 0.05). Seizure duration was not significantly different during the three treatments.
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Affiliation(s)
- K H Simpson
- University Department of Anaesthesia, St James's University Hospital, Leeds
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40
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41
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Abstract
Winnie and co-workers described a technique of blocking the lateral cutaneous nerve of thigh, femoral and obturator nerves using one injection of local anaesthetic into the fibrous sheath surrounding the femoral nerve. We studied 40 patients undergoing biopsy of vastus medialis for investigation of malignant hyperpyrexia, for onset, quality and recovery from this block. The patients were assigned in a random double-blind fashion to receive 0.6 ml kg-1 of one of two anaesthetic solutions: 1% lignocaine with 1 in 100,000 noradrenaline or 0.25% bupivacaine. Bupivacaine produced a similar onset time but longer duration of action compared with lignocaine. Median peak plasma concentrations of six patients in each group did not approach values associated with toxicity. This study demonstrated a 12.5% and 87.5% partial and complete femoral nerve block, respectively, and a 67.5% success rate for lateral cutaneous nerve of thigh using Winnie's technique. There was no clinical evidence of obturator nerve block.
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Affiliation(s)
- T H Madej
- University Department of Anaesthesia, St Jame's University Hospital, Leeds
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42
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Abstract
The occurrence of masseteric muscle spasm (MMS) in children is thought to be frequent and to be associated usually with malignant hyperpyrexia (MH). We have found a lower incidence of MMS in children and 50% had no muscle abnormality. Clinical features that support a diagnosis of MH include high serum creatine kinase (CK) concentration and the presence of myoglobinuria. There is evidence to suggest that suxamethonium does increase jaw tone in adults and children, and an exaggerated response may be taken clinically to be MMS. However, MMS should still be regarded as an early warning sign of MH.
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Affiliation(s)
- A S Christian
- University Department of Anaesthesia, St James's University Hospital, Leeds
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44
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Simpson KH, Halsall PJ, Carr CM, Stewart KG. Propofol reduces seizure duration in patients having anaesthesia for electroconvulsive therapy. Br J Anaesth 1988; 61:343-4. [PMID: 3263142 DOI: 10.1093/bja/61.3.343] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Twenty-five patients received either methohexitone 1.0 mg kg-1 or propofol 1.3 mg kg-1 to induce anaesthesia during two separate electroconvulsive therapy (ECT) treatments. A forearm was isolated before administration of suxamethonium 0.5 mg kg-1, so that unmodified seizure duration could be measured. Bifrontotemporal electrodes were applied to administer a standard 3-s ECT shock. Median (quartile deviation) duration of seizure was reduced significantly after propofol (19.0 (9.0) s), compared with after methohexitone (33.0 (7.8) s). Therefore propofol may not be an appropriate anaesthetic for ECT because of its adverse effect on seizure duration.
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Affiliation(s)
- K H Simpson
- University Department of Anaesthesia, St James's University Hospital, Leeds, Yorks
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45
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46
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Abstract
This paper reports three investigations of the suggested relationship between sudden infant death syndrome (SIDS) and malignant hyperpyrexia (MH). In the first study 151 MH-susceptible families completed a questionnaire designed to identify the incidence of SIDS within their own pedigree. In the second study 106 SIDS families completed a questionnaire designed to identify the incidence of anaesthetic related problems. In the third study, 14 SIDS parents were subjected to muscle biopsy and in vitro halothane contracture and caffeine contracture screening for susceptibility to MH. From the results of the three studies it can be concluded that there is no association between SIDS and MH.
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Affiliation(s)
- F R Ellis
- University Department of Anaesthesia, St James's University Hospital, Leeds, Yorks
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Green JH, Ellis FR, Halsall PJ, Campbell IT, Currie S, Caddy J. Thermoregulation, plasma catecholamine and metabolite levels during submaximal work in individuals susceptible to malignant hyperpyrexia. Acta Anaesthesiol Scand 1987; 31:122-6. [PMID: 3564867 DOI: 10.1111/j.1399-6576.1987.tb02533.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Measurements of body temperature, respiratory gas exchange, sweat evaporation rate and circulating levels of catecholamines, lactate, pyruvate, free fatty acids and glucose were made in seven patients susceptible to malignant hyperpyrexia (MHS) and in seven control subjects during 2 h of treadmill walking at 40% of maximum oxygen consumption. These studies took place in an ambient temperature of 22 degrees C. The MHS patients displayed the same thermoregulatory, plasma catecholamine and metabolic responses as the control subjects. The results of the present study suggest that non-competitive, low-intensity, steady-state exercise need not be contraindicated for MHS patients.
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Kelway B, Simpson KH, Smith RJ, Halsall PJ. Effects of atropine and glycopyrrolate on cognitive function following anaesthesia and electroconvulsive therapy (ECT). Int Clin Psychopharmacol 1986; 1:296-302. [PMID: 3549875 DOI: 10.1097/00004850-198610000-00003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Memory changes are known to be associated with electroconvulsive therapy (ECT). The anticholinergic drugs used prior to the procedure have also been suspected of causing cognitive deficits. The present study was designed to assess memory and concentration in depressed patients receiving 0.6 mg atropine, 0.2 mg glycopyrrolate or placebo before anaesthesia and ECT. Glycopyrrolate is an anticholinergic agent lacking central nervous system effects. Anaesthesia and bilateral ECT resulted in significant short-term memory deficit, but this was seen equally in each of the groups of patients irrespective of which premedication was given. As no regimen was superior, as far as effect on memory is concerned, premedication for ECT should be chosen according to other criteria.
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49
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Abstract
A detailed account of the procedure of muscle biopsy for screening patients suspected of being susceptible to malignant hyperpyrexia is given, together with a review of the results obtained from 1127 patients screened over the last 14 years. The information should help anaesthetists to discuss the investigation fully with probands and other members of their families before referral for further specific investigation.
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50
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Ellis FR, Halsall PJ. Susceptibility to malignant hyperpyrexia. Anaesthesia 1986; 41:85-6. [PMID: 3946783 DOI: 10.1111/j.1365-2044.1986.tb12717.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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