Search

Background: Malignant hyperthermia is a potentially lethal condition triggered by specific anesthetic drugs, especially a depolarizing muscle relaxant of succinylcholine (Suxamethonium). Despite the frequent use of succinylcholine with electroconvulsive therapy (ECT), there has been no reported case of potentially lethal malignant hyperthermia following ECT. In addition, the time interval between the administration of succinylcholine and the onset of malignant hyperthermia has not been outlined in the context of ECT., Case Presentation: We present the case of a 79-year-old woman suffering from severe depression, who experienced severe malignant hyperthermia due to succinylcholine administration during an ECT session. She presented with a high fever of 40.2 °C, tachycardia of 140/min, hypertension with a blood pressure exceeding 200 mmHg, significant muscle rigidity, and impaired consciousness. These symptoms emerged two hours after ECT, which occurred in a psychiatric ward rather than an operating room, and reached their peak in less than 24 h. She was given 60 mg of dantrolene, which quickly reduced the muscular rigidity. Subsequently, she received two additional doses of 20 mg and 60 mg of dantrolene, which brought her fever down to 36.2 °C and completely eased her muscle rigidity within two days after ECT., Conclusions: This is the first reported case of potentially lethal malignant hyperthermia after ECT. In addition, it highlights the delayed onset of malignant hyperthermia following an ECT procedure, emphasizing the necessity for psychiatrists to recognize its onset even after the treatment. In the light of potentially lethal consequences of malignant hyperthermia, it is critically important for psychiatrists to closely monitor both intraoperative and postoperative patient's vital signs and characteristic physical presentations, promptly identify any symptomatic emergence, and treat it immediately with dantrolene., (© 2024. The Author(s).)

Rationale: Malignant hyperthermia (MH) is a rare yet serious medical complication that typically arises following general anesthesia or the administration of specific anesthetics. Due to the infrequency of MH, anesthesiologists often lack sufficient expertise in identifying and managing it, leading to misdiagnosis and inappropriate treatment. There is an urgent need to enhance the diagnosis and management of MH through the utilization of relevant tools., Patient Concerns: In this case, a 52-year-old woman underwent radical cervical cancer surgery under general anesthesia, with no family or significant medical history. She experienced a gradual increase in end-tidal carbon dioxide (ETCO2) to a maximum of 75 mm Hg and a rise in body temperature from 36.5 to 37.5 °C in a very short period, as well as a blood gas analysis showing a pH of 7.217., Diagnosis: The anesthesiologist immediately used The WeChat applet-based National Remote Emergency System for Malignant Hyperthermia (MH-NRES), and the score was 40, which indicated that the patient was very likely to have MH., Interventions: We immediately discontinued sevoflurane and switched total intravenous anesthesia to maintain general anesthesia, with a rapid intravenous infusion of dantrolene sodium., Outcomes: The ETCO2 and the temperature quickly dropped to normal, followed by successful completion of the surgery, and the patient was discharged 8 days after surgery., Lessons: The experience can provide a basis use of MH-NRES and improve the ability of anesthesiologists to deal with intraoperative MH as well as increase the survival probability of patients., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

We report an unusual case of highly suspected malignant hyperthermia after inducing anesthesia in a brain-dead 18-year-old male patient undergoing organ procurement surgery. The patient was administered desflurane (3 vol%) and rocuronium bromide (50 mg) to induce and maintain general anesthesia. He experienced hypercapnia and tachycardia within 5 minutes of anesthesia induction; however, his body temperature rapidly rose only after 15 minutes. The volatile anesthetic was discontinued, and dantrolene was administered at a low dose (1 mg/kg) to avert possible hepatotoxic effects on the donor liver. Fortunately, the clinical course of the brain-dead donor until the organs were harvested and the liver transplantation outcome of the recipient was favorable. A comprehensive understanding of the pathophysiology of brain death, organ transplantation, and malignant hyperthermia is essential to respond promptly and appropriately. Based on our experience, low-dose dantrolene may be clinically used in brain-dead donors while accounting for its potential hepatotoxic effects., Competing Interests: Declaration of Competing Interest All the authors declare no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Case: A 49-year-old woman presented with a displaced left posterior wall acetabular fracture-dislocation and a left comminuted intra-articular distal radius fracture sustained in a motor vehicle accident. Fifteen minutes after anesthesia induction for operative fixation of the fractures, the patient experienced severe hypertension, increased end-tidal carbon dioxide, and fever. A diagnosis of malignant hyperthermia (MH) was made before incision. The patient was medically stabilized, and her acetabular fracture-dislocation was placed in skeletal traction until she was deemed fit for surgery 4 days later., Conclusion: This case report highlights the importance of early recognition of MH and perioperative management., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSCC/C181)., (Copyright © 2023 by The Journal of Bone and Joint Surgery, Incorporated.)

Biochemical reactions in cells serve as the endogenous source of heat, maintaining a constant body temperature. This process requires proper control; otherwise, serious consequences can arise due to the unwanted but unavoidable responses of biological systems to heat. This review aims to present a range of responses to heat in biological systems across various spatial scales. We begin by examining the impaired thermogenesis of malignant hyperthermia in model mice and skeletal muscle cells, demonstrating that the progression of this disease is caused by a positive feedback loop between thermally driven Ca2+ signaling and thermogenesis at the subcellular scale. After we explore thermally driven force generation in both muscle and non-muscle cells, we illustrate how in vitro assays using purified proteins can reveal the heat-responsive properties of proteins and protein assemblies. Building on these experimental findings, we propose the concept of 'trans-scale thermal signaling'., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Japanese Biochemical Society.)

Background: In trigger-free anesthesia a volatile anesthetic concentration of 5 parts per million (ppm) should not be exceeded. According to European Malignant Hyperthermia Group (EMHG) guideline, this may be achieved by removing the vapor, changing the anesthetic breathing circuit and renewing the soda lime canister followed by flushing with O 2 or air for a workstation specific time. Reduction of the fresh gas flow (FGF) or stand-by modes are known to cause rebound effects. In this study, simulated trigger-free pediatric and adult ventilation was carried out on test lungs including ventilation maneuvers commonly used in clinical practice. The goal of this study was to evaluate whether rebounds of sevoflurane develop during trigger-free anesthesia., Methods: A Dräger® Primus® was contaminated with decreasing concentrations of sevoflurane for 120 min. Then, the machine was prepared for trigger-free anesthesia according to EMHG guideline by changing recommended parts and flushing the breathing circuits using 10 or 18 l⋅min - 1 FGF. The machine was neither switched off after preparation nor was FGF reduced. Simulated trigger-free ventilation was performed with volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) including various ventilation maneuvers like pressure support ventilation (PSV), apnea, decreased lung compliance (DLC), recruitment maneuvers, prolonged expiration and manual ventilation (MV). A high-resolution ion mobility spectrometer with gas chromatographic pre-separation was used to measure sevoflurane in the ventilation gas mixture in a 20 s interval., Results: Immediately after start of simulated anesthesia, there was an initial peak of 11-18 ppm sevoflurane in all experiments. The concentration dropped below 5 ppm after 2-3 min during adult and 4-18 min during pediatric ventilation. Other rebounds of sevoflurane > 5 ppm occurred after apnea, DLC and PSV. MV resulted in a decrease of sevoflurane < 5 ppm within 1 min., Conclusion: This study shows that after guideline-compliant preparation for trigger-free ventilation anesthetic machines may develop rebounds of sevoflurane > 5 ppm during typical maneuvers used in clinical practice. The changes in rate and direction of internal gas flow during different ventilation modes and maneuvers are possible explanations. Therefore, manufacturers should provide machine-specific washout protocols or emphasize the use of active charcoal filters (ACF) for trigger-free anesthesia., (© 2023. The Author(s).)

Background: Malignant hyperthermia is an extremely dangerous condition that can occur with exposure to volatile inhalant anesthetics and depolarizing muscle relaxants, and that requires immediate intervention. Neurological complications have rarely been reported, with no reports of electroencephalographic abnormalities or encephalopathy. Here, we report a case of severe electroencephalographic abnormality in the acute phase of malignant hyperthermia that eventually led to diffuse cerebral cortical damage., Case Presentation: A 15-month-old Japanese boy underwent a Rastelli procedure to correct a double-outlet right ventricle and pulmonary atresia. Sevoflurane was used for induction and maintenance of anesthesia during surgery. After withdrawal from the heart-lung machine, his body temperature rose at a rate of 0.1 ℃/minute, and when he left the operating room, his core body temperature had reached 42 ℃. After admission to the intensive care unit, tachycardia, high PaCO 2 , and progressive metabolic acidosis were observed. A clinical grading scale score of 63 indicated malignant hyperthermia, and dantrolene was administered. The pupils were dilated, and the electroencephalogram showed persistent generalized continuous multifocal spikes. Midazolam, levetiracetam, and fosphenytoin were administered without improvement, and thiamylal and ketamine were infused continuously. After the electroencephalogram shifted to burst suppression, the epileptic firing gradually decreased, and the background electroencephalogram became lower in amplitude. Magnetic resonance imaging of the head performed after the patient was hemodynamically stable suggested diffuse cerebral cortical damage. Severe mental retardation, hypertonia, and quadriplegia were observed as neurological complications., Conclusions: In this case, despite the use of high-dose anticonvulsants, the patient showed severe electroencephalogram abnormality, resulting in diffuse cortical damage. Hyperthermia is known to damage the central nervous system by causing increased brain pressure and cerebral edema, which may have triggered the severe neuronal excitation that we observed in this case. The presence of systemic inflammatory response syndrome and the patient's background, including young age and ethnicity, might also have been factors. Malignant hyperthermia can be complicated by encephalopathy, and continuous electroencephalogram monitoring should be considered., (© 2023. The Author(s).)

Malignant hyperthermia (MH) is a life-threatening syndrome caused by sudden, uncontrolled skeletal muscle hypermetabolism in response to inhalation anesthetics and depolarizing relaxants. The estimated incidence of MH is between 1:10,000 and 1:250,000 anesthetic procedures. In Poland, due to lack of reporting, the incidence of MH is unknown. Dantrolene is imported as a life-saving drug (target import) and temporally authorized for sale. The aim of the study was to evaluate the prevalence of malignant hyperthermia in Poland and to assess the accessibility to dantrolene in Poland. A questionnaire was conducted among the chiefs of anesthesia and intensive care units in Poland. During the years 2014 to 2019, 10 episodes of MH have been reported in 238 surveyed polish anesthesia departments. The estimated prevalence is 1:350,000. Eight patients survived the MH crisis. Dantrolene is stocked in 48 (20%) anesthesiology departments. Among the surveyed hospitals, only in 38 (16%) it is possible to administer dantrolene within 5 minutes of suspecting a MH reaction. Less than half units (44%) have an algorithm for the management of MH episode in the operating theaters. The results of the study revealed, that the prevalence of MH in Poland is lower than the prevalence reported in other countries. Access to dantrolene in Poland is limited., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Malignant hyperthermia (MH) is a rare but life-threatening genetic disorder of the skeletal muscles triggered by inhalation anesthetics or succinylcholine. A 49-year-old female developed symptoms of MH shortly after a lumbar surgery. Despite being insidious, MH was diagnosed based on the clinical grading scale. We incidentally discovered fine fasciculations in extremities while inserting an ultrasound-guided arterial catheter. On receiving dantrolene, her symptoms improved within 20 minutes; a subsequent ultrasound revealed no fasciculations. Although halothane contracture testing was not available, the fasciculations that resolved with dantrolene administration in a MH suspected patient opens up a new potential avenue of diagnostics., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 International Anesthesia Research Society.)

Objectives: Malignant hyperthermia (MH) susceptibility caries broad implications for the care of pediatric surgical patients. While precautions must often be taken for only a vague family history, two options exist to assess MH-susceptibility. We evaluate the use of MH precautions and susceptibility testing at a freestanding children's hospital., Methods: This single institution retrospective cohort study identified patients of any age who received general anesthetics utilizing MH precautions over a five-year period. The electronic medical record was further queried for patients diagnosed with MH. The indication for MH precautions and uses of susceptibility testing are assessed. Secondary outcomes included a diagnosis of bona fide MH., Results: A total of 125 patients received 174 anesthetics with MH precautions at a mean age of 114 months (0-363 months). Otolaryngology was the procedural service most frequently involved in the care of the cohort (n = 45; 26%). A reported personal or family history of MH (n = 102; 59%) was the most common indication for precautions, followed by muscular dystrophy (n = 29; 17%). No MH events occurred in the cohort and further review of ICD-9 and -10 diagnosis codes found no MH diagnoses. No study subjects received muscle biopsy and contracture testing and only 5 (4%) underwent genetic testing for genomic variants known to cause MH susceptibility. A case example is given to highlight the implications of a reported MH history., Conclusion: Otolaryngologists should maintain a familiarity with the precautions necessary to manage patients at risk for MH and MH-like reactions. Without an accessible test to rule out susceptibility, surgeons must rely on a careful history to appropriately utilize precautions. An inappropriate label of "MH-susceptible" may result in decreased access to care and treatment delays., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Malignant hyperthermia (MH) is a life-threatening reaction triggered by volatile anesthetics and succinylcholine. MH is caused by mutations in the skeletal muscle ryanodine receptor (RYR1) gene, as is rhabdomyolysis triggered by exertion and/or pyrexia. The discrepancy between the prevalence of risk genotypes and actual MH incidence remains unexplained. We investigated the role of pre-operative exercise and pyrexia as potential MH modifying factors. We included cases from 5 MH referral centers with 1) clinical features suggestive of MH, 2) confirmation of MH susceptibility on Contracture Testing (IVCT or CHCT) and/or RYR1 genetic testing, and a history of 3) strenuous exercise within 72 h and/or pyrexia >37.5 °C prior to the triggering anesthetic. Characteristics of MH-triggering agents, surgery and succinylcholine use were collected. We identified 41 cases with general anesthesias resulting in an MH event (GA+MH, n = 41) within 72 h of strenuous exercise and/or pyrexia. We also identified previous general anesthesias without MH events (GA-MH, n = 51) in the index cases and their MH susceptible relatives. Apart from pre-operative exercise and/or pyrexia, trauma and acute abdomen as surgery indications, emergency surgery and succinylcholine use were also more common with GA+MH events. These observations suggest a link between pre-operative exercise, pyrexia and MH., Competing Interests: Declaration of Competing Interest This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Malignant hyperthermia (MH) is an inherited muscle disorder induced by volatile anesthetics and depolarizing muscle relaxants. While the incidence of MH is high in young, there are few reports on the clinical features of pediatric MH. In this study, we selected pediatric cases from an MH database and analyzed the clinical findings by age group. We hypothesized that there would be age-related differences in the clinical characteristics., Methods: A retrospective analysis of MH data collected in our database during 1960 to 2020 was performed to identify pediatric subjects (≤18 years) with a Clinical Grading Scale of ≥35, indicating "very likely" or "almost certain" MH. We compared clinical characteristics among the 0 to 24 month, 2 to 12 year, and 13 to 18 year (youngest, middle, and oldest, respectively) age groups., Results: Data were available for 187 patients: 15 in the youngest age group, 123 in the middle-aged group, and 49 in the oldest age group. Of these, 55 patients (29.4%) had undergone muscle biopsy and muscle contracture test. The mortality rates during the study period were 13.3%, 13.8%, 20.4%, and 15.5% in the youngest, middle, and oldest cohorts and overall, respectively. In contrast, the overall mortality rate from 2000 to 2020 was 8.8%. The most frequent initial symptoms of MH were elevated temperature (46.7%) and generalized muscular rigidity (26.7%) in the youngest cohort, masseter spasm (35.0%) and generalized muscular rigidity (19.5%) in the middle cohort, and elevated end-tidal carbon dioxide (26.5%) and tachycardia (22.4%) in the oldest cohort. Physical examination revealed that elevated temperature, sinus tachycardia, and respiratory acidosis occurred frequently in all groups. The middle cohort had high frequencies of masseter spasm (58.4%; P = .02) and dark urine (75.5%; P = .01) compared to those in the oldest groups, and had a higher peak creatine kinase level compared to those in the 3 groups. Skeletal muscle symptoms tended to be more common in patients administered succinylcholine (generalized muscular rigidity, P = .053; masseter spasm, P < .0001; dark urine, P < .0001). In particular, masseter spasm and dark urine were more common in the middle cohort when succinylcholine was administered (masseter spasm: versus youngest cohort, P = .06, versus oldest cohort, P = .027; dark urine: versus youngest cohort, P = .0072, versus oldest cohort, P = .0015)., Conclusions: The clinical characteristics of pediatric patients with MH vary according to age group. The difference in initial symptoms of MH depending on age group is noteworthy information for the early diagnosis of MH., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 International Anesthesia Research Society.)

Abstract: A patient with Klinefelter syndrome and skeletal Class III malocclusion experienced a malignant hyperthermia-like reaction while undergoing orthognathic surgery. The patient fully recovered after prompt diagnosis and management, and surgery was reattempted under total intravenous anesthesia. The patient was discharged without any anesthetic complications and was satisfied with the surgical results. This is the first described case of a malignant hyperthermia-like event in a patient with Klinefelter syndrome. Total intravenous anesthesia may be safely administered in malignant hyperthermia-susceptible patients who require orthognathic surgery., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)

Background: Calsequestrins (Casqs), comprising the Casq1 and Casq2 isoforms, buffer Ca 2+ and regulate its release in the sarcoplasmic reticulum of skeletal and cardiac muscle, respectively. Human inherited diseases associated with mutations in CASQ1 or CASQ2 include malignant hyperthermia/environmental heat stroke (MH/EHS) and catecholaminergic polymorphic ventricular tachycardia. However, patients with an MH/EHS event often experience arrhythmia for which the underlying mechanism remains unknown., Methods: Working hearts from conventional ( Casq1 -KO) and cardiac-specific ( Casq1 -CKO) Casq1 knockout mice were monitored in vivo and ex vivo by ECG and electric mapping, respectively. MH was induced by 2% isoflurane and treated intraperitoneally with dantrolene. Time-lapse imaging was used to monitor intracellular Ca 2+ activity in isolated mouse cardiomyocytes or neonatal rat ventricular myocytes with knockdown, overexpression, or truncation of the Casq1 gene. Conformational change in both Casqs was determined by cross-linking Western blot analysis., Results: Like patients with MH/EHS, Casq1 -KO and Casq1 -CKO mice had faster basal heart rate and ventricular tachycardia on exposure to 2% isoflurane, which could be relieved by dantrolene. Basal sinus tachycardia and ventricular ectopic electric triggering also occurred in Casq1 -KO hearts ex vivo. Accordingly, the ventricular cardiomyocytes from Casq1 -CKO mice displayed dantrolene-sensitive increased Ca 2+ waves and diastole premature Ca 2+ transients/oscillations on isoflurane. Neonatal rat ventricular myocytes with Casq1-knockdown had enhanced spontaneous Ca 2+ sparks/transients on isoflurane, whereas cells overexpressing Casq1 exhibited decreased Ca 2+ sparks/transients that were absent in cells with truncation of 9 amino acids at the C terminus of Casq1. Structural evaluation showed that most of the Casq1 protein was present as a polymer and physically interacted with ryanodine receptor-2 in the ventricular sarcoplasmic reticulum. The Casq1 isoform was also expressed in human myocardium. Mechanistically, exposure to 2% isoflurane or heating at 41 °C induced Casq1 oligomerization in mouse ventricular and skeletal muscle tissues, leading to a reduced Casq1/ryanodine receptor-2 interaction and increased ryanodine receptor-2 activity in the ventricle., Conclusions: Casq1 is expressed in the heart, where it regulates sarcoplasmic reticulum Ca 2+ release and heart rate. Casq1 deficiency independently causes MH/EHS-like ventricular arrhythmia by trigger-induced Casq1 oligomerization and a relief of its inhibitory effect on ryanodine receptor-2-mediated Ca 2+ release, thus revealing a new inherited arrhythmia and a novel mechanism for MH/EHS arrhythmogenesis.

Introduction : Many drugs are known to induce malignant syndromes. The most common malignant syndromes are induced by the use of antipsychotics and anesthetics and the withdrawal of anti-Parkinson drugs. As the clinical manifestations of antipsychotic malignant syndrome, Parkinson's disease hyperpyrexia syndrome and anesthetic-induced malignant syndrome are very similar, they are easily confused in the clinic. Areas covered : We reviewed articles published between 1960 and April 2021 describing malignant syndromes. This paper provides a detailed literature review of malignant syndromes and important guidance for the diagnosis and treatment of malignant syndromes to clinicians. Expert opinion : Although malignant syndromes are rare conditions with a low incidence, these conditions usually progress rapidly and can endanger patients' lives, meriting attention from clinicians. The typical clinical manifestations of malignant syndromes are hyperpyrexia, muscular rigidity, an altered mental status and increased levels of creatine kinase; however, the pathophysiology, treatment and prognosis of different malignant syndromes are quite different. Prompt diagnosis and treatment may significantly improve the prognosis of patients with malignant syndromes.

Introduction: Malignant hyperthermia (MH) and exertional rhabdomyolysis (ERM) have long been considered episodic phenotypes occurring in response to external triggers in otherwise healthy individuals with variants in RYR1. However, recent studies have demonstrated a clinical and histopathological continuum between patients with RYR1-related congenital myopathies and those with ERM or MH susceptibility. Furthermore, animal studies have shown non-neuromuscular features such as a mild bleeding disorder and an immunological gain-of-function associated with MH/ERM related RYR1 variants raising important questions for further research. Awareness of the neuromuscular disease spectrum and potential multisystem involvement in RYR1-related MH and ERM is essential to optimize the diagnostic work-up, improve counselling and and future treatment strategies for patients affected by these conditions. This study will examine in detail the nature and severity of continuous disease manifestations and their effect on daily life in patients with RYR1-related MH and ERM., Methods: The study protocol consists of four parts; an online questionnaire study, a clinical observational study, muscle imaging, and specific immunological studies. Patients with RYR1-related MH susceptibility and ERM will be included. The imaging, immunological and clinical studies will have a cross-sectional design, while the questionnaire study will be performed three times during a year to assess disease impact, daily living activities, fatigue and pain. The imaging study consists of muscle ultrasound and whole-body magnetic resonance imaging studies. For the immunological studies, peripheral mononuclear blood cells will be isolated for in vitro stimulation with toll-like receptor ligands, to examine the role of the immune system in the pathophysiology of RYR1-related MH and ERM., Discussion: This study will increase knowledge of the full spectrum of neuromuscular and multisystem features of RYR1-related MH and ERM and will establish a well-characterized baseline cohort for future studies on RYR1-related disorders. The results of this study are expected to improve recognition of RYR1-related symptoms, counselling and a more personalized approach to patients affected by these conditions. Furthermore, results will create new insights in the role of the immune system in the pathophysiology of MH and ERM., Trial Registration: This study was pre-registered at ClinicalTrials.gov (ID: NCT04610619)., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Rationale: Several hereditary myopathies that can predispose to malignant hyperthermia (MH) are reported. However, the risk of MH in myotonic dystrophy type I (DM1) has been suggested equal to general population, although the evidence is limited to only a few case reports., Patient Concerns: We encountered a rare case of MH during anesthesia induction with sevoflurane in a male adolescent with previously undiagnosed DM1., Diagnoses: After the event, genetic testing revealed the presence of a previously unknown heterozygous missense mutation in ryanodine receptor 1 (RYR1) associated with MH (c.6898T > C; p.ser2300Pro). Concomitantly, the patient was diagnosed with DM1 with abnormal cytosine-thymine-guanine triplet expansion in the DMPK gene., Interventions: Dantrolene was administered to treat the hypermetabolic manifestations in 20 minutes after the identification of MH., Outcomes: The patient was successfully treated and discharged without any complications. Laboratory abnormalities were recovered to baseline at postoperative 4 days., Lessons: The authors suggest that possible MH susceptibility in DM1 patients may be refocused. Genetic testing can be a screening tool for MH susceptibility in these population, prior to receiving general anesthesia., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Malignant hyperthermia (MH) is a rare genetic disease characterized by the development of very serious symptoms, and hence prompt and appropriate treatment is required. However, postoperative MH is very rare, representing only 1.9% of cases as reported in the North American Malignant Hyperthermia Registry (NAMHR). We report a rare case of a patient who developed sudden postoperative hyperthermia after mastectomy, which was definitively diagnosed as MH by the calcium-induced calcium release rate (CICR) measurement test., Case Presentation: A 61-year-old Japanese woman with a history of stroke was hospitalized for breast cancer surgery. General anesthesia was introduced by propofol, remifentanil, and rocuronium. After intubation, anesthesia was maintained using propofol and remifentanil, and mastectomy and muscle flap reconstruction surgery was performed and completed without any major problems. After confirming her spontaneous breathing, sugammadex was administered and she was extubated. Thereafter, systemic shivering and masseter spasm appeared, and a rapid increase in body temperature (maximum: 38.9 °C) and end-tidal carbon dioxide (ETCO 2 ) (maximum: 59 mmHg) was noted. We suspected MH and started cooling the body surface of the axilla, cervix, and body trunk, and administered chilled potassium-free fluid and dantrolene. After her body temperature dropped and her shivering improved, dantrolene administration was ended, and finally she was taken to the intensive care unit (ICU). Body cooling was continued within the target range of 36-37 °C in the ICU. No consciousness disorder, hypotension, increased serum potassium level, metabolic acidosis, or cola-colored urine was observed during her ICU stay. Subsequently, her general condition improved and she was discharged on day 12. Muscle biopsy after discharge was performed and provided a definitive diagnosis of MH., Conclusions: The occurrence of MH can be life-threatening, but its frequency is very low, and genetic testing and muscle biopsy are required to confirm the diagnosis. On retrospective evaluation using the malignant hyperthermia scale, the present case was almost certainly that of a patient with MH. Prompt recognition and immediate treatment with dantrolene administration and body cooling effectively reversed a potentially fatal syndrome. This was hence a valuable case of a patient with postoperative MH that led to a confirmed diagnosis by CICR.

Malignant hyperthermia (MH) is caused by a genetic disorder of the skeletal muscle that induces a hypermetabolic response when patients are exposed to a triggering agent such as volatile inhaled anesthetics or depolarizing neuromuscular blockers. Symptoms of MH include increased carbon dioxide production, hyperthermia, muscle rigidity, tachypnea, tachycardia, acidosis, hyperkalemia, and rhabdomyolysis. Common scenarios for triggering agents are those used are during surgery and rapid sequence intubation. Hypermetabolic symptoms have a rapid onset; hence, prompt recognition and treatment are vital to prevent morbidity and mortality. The first-line treatment agent for an MH response is dantrolene. Further treatment includes managing complications related to a hypermetabolic response such as hyperkalemia and arrhythmias. This review is focused on the recognition and treatment considerations of MH in the emergency department to optimize therapy and improve patient morbidity and mortality., Competing Interests: Disclosure: The authors report no conflicts of interests., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Malignant hyperthermia (MH) is a rare but potentially fatal complication of exposure to certain anesthetic drugs. However, stress-induced MH, initially observed in pigs undergoing intense physical or emotional strain, has been reported in the absence of anesthetic exposure. In this case report, we describe a case of postoperative hyperthermia and cardiac dysfunction suspicious for stress-induced MH occurring after an endobronchial biopsy in a patient with recurrent undiagnosed fevers. We also examine our diagnosis of stress-induced MH and possible preventive measures to avoid this complication., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 International Anesthesia Research Society.)

We report a case of rhabdomyolysis during a perioperative period after cardiac surgery. A 47-yearold man underwent aortic root replacement for annuloaortic ectasia under general anesthesia using sevoflurane, fentanyl, remifentanil, rocronium bromide and midazolam. On the 1st postoperative day (1 POD), his body temperature rose over 38 ℃, which continued for 3 days despite our attempt to stabilize the fever. On 4 POD, his laboratory data and hemodynamics dramatically worsened, and we commenced continuous hemodialysis filtration (CHDF) and percutaneous cardiopulmonary support system (PCPS). In addition, balloon pumping (IABP) was started on 5 POD. At the same time, we initiated dantrolene sodium hydrate infusion according to a clinical grading scale to predict malignant hyperthermia (MH) susceptibility. Serum creatine phosphokinase (CPK) increased over 350,000 U/l on the 7 POD, and dantrolene sodium hydrate was continuously infused until 9 POD. Despite dantrolene sodium infusion, CHDF, IABP and PCPS, his condition did not improve, and he died of disseminated intravascular coagulation syndrome (DIC) and sepsis on 28 POD. Computed tomography on 21 POD disclosed scattered low-density areas in the erector spinal, lliopsoas and femoral muscles, which indicated rhabdomyolysis. Histopathological examination using hematoxylin and eosin stain revealed destroyed striated-muscle fibers and swelling rhabdomyocytes. It remained unclear which drug triggered rhabdomyolysis. When MH is suspected, we should consider the use of the clinical grading scale to predict its susceptibility and start dantrolene sodium hydrate infusion.

Background: Statin intake is associated with muscular side effects, among which the unmasking of latent myopathies and of malignant hyperthermia (MH) susceptibility have been reported. These findings, together with experimental data in small animals, prompt speculation that statin therapy may compromise the performance of skeletal muscle during diagnostic in vitro contracture tests (IVCT). In addition, statins might reduce triggering thresholds in susceptible individuals (MHS), or exacerbate MH progression. We sought to obtain empirical data to address these questions., Methods: We compared the responses of 3 different muscles from untreated or simvastatin treated MHS and non-susceptible (MHN) pigs. MHS animals were also invasively monitored for signs of impending MH during sevoflurane anesthesia., Results: Muscles from statin treated MHS pigs responded with enhanced in vitro contractures to halothane, while responses to caffeine were unaltered by the treatment. Neither agent elicited contractures in muscles from statin treated MHN pigs. In vivo, end- tide pCO2, hemodynamic evolution, plasma pH, potassium and lactate concentrations consistently pointed to mild acceleration of MH development in statin-treated pigs, whereas masseter spasm and rigor faded compared to untreated MHS animals., Conclusions: The diagnostic sensitivity and specificity of the IVCT remains unchanged by a short-term simvastatin treatment in MHS swine. Evidence of modest enhancement in cardiovascular and metabolic signs of MH, as well as masked pathognomonic muscle rigor observed under simvastatin therapy suggest a potentially misleading influence on the clinical presentation of MH. The findings deserve further study to include other statins and therapeutic regimes.

Mutations in the skeletal muscle Ca 2+ release channel, the type 1 ryanodine receptor (RYR1), cause malignant hyperthermia susceptibility (MHS) and a life-threatening sensitivity to heat, which is most severe in children. Mice with an MHS-associated mutation in Ryr1 (Y524S, YS) display lethal muscle contractures in response to heat. Here we show that the heat response in the YS mice is exacerbated by brown fat adaptive thermogenesis. In addition, the YS mice have more brown adipose tissue thermogenic capacity than their littermate controls. Blood lactate levels are elevated in both heat-sensitive MHS patients with RYR1 mutations and YS mice due to Ca 2+ driven increases in muscle metabolism. Lactate increases brown adipogenesis in both mouse and human brown preadipocytes. This study suggests that simple lifestyle modifications such as avoiding extreme temperatures and maintaining thermoneutrality could decrease the risk of life-threatening responses to heat and exercise in individuals with RYR1 pathogenic variants.

Introduction: Drug-induced fever is easy to overlook in respiratory departments. High fever is a rare side effect of trihexyphenidyl, which can be used clinically to treat Parkinson's disease. Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a group of clinical syndromes caused by various diseases, resulting in water retention and refractory hyponatremia. However, pneumonia combined with malignant hyperthermia and SIADH has rarely been reported. We describe an unusual case of malignant hyperthermia and refractory hyponatremia due to trihexyphenidyl adverse reaction., Patient Concerns: Fifty-five-year-old male with pneumonia presented with malignant hyperthermia and refractory hyponatremia has a history of Parkinson's disease., Diagnosis: Early considerations related the described hyperthermia findings to the manifestations of pneumonia. However, the last findings were due to trihexyphenidyl adverse reaction., Interventions: Broad-spectrum antibiotics, oral and intravenous supplement of concentrated sodium chloride, drug, and physical cooling., Outcomes: The patient survived. During the 3-month follow up, the patient was no recurrence of fever or hyponatremia., Conclusion: High fever and SIADH can be a rare adverse reaction to trihexyphenidyl. Therefore, possible drug factors should be considered in the case. Consideration of other possible causes can improve early diagnosis and treatment of patients with fever of unknown origins.

A 20-year-old man with a rare neurodegenerative disease developed hypermetabolic symptoms with dyskinesia after a third ventriculostomy for hydrocephalus. The initial presentation was concerning for an acute dystonic reaction after metoclopramide was administered for nausea. He concurrently developed hypermetabolic symptoms, including hyperthermia, tachycardia, and a lactic acidosis. The diagnosis was broadened to include neuroleptic malignant syndrome, serotonin syndrome, and malignant hyperthermia. Although perhaps less intellectually satisfying but more true to clinical reality, we did not isolate a single diagnosis but treated effectively all 3 with dantrolene sodium and benzodiazepine.

Competing Interests: Conflict of Interest The authors have no conflicts of interest to disclose.

Objective: To report on a case of malignant hyperthermia in a child after a magnetic resonance imaging of the skull was performed using sevoflurane anesthesia., Case Description: A 3-year-old boy admitted to the pediatric intensive care unit after presenting clinical and laboratory findings consistent with unspecified viral meningoencephalitis. While the patient was sedated, a magnetic resonance imaging of the skul was performed using propofol followed by the administration of sevoflurane through a laryngeal mask in order to continue anesthesia. Approximately three hours after the start of the procedure, the patient presented persistent tachycardia, tachypnea, generalized muscular stiffness and hyperthermia. With a diagnostic hypothesis of malignant hyperthermia, dantrolene was then administered, which immediately induced muscle stiffness, tachycardia, tachypnea and reduced body temperature., Comments: Malignant hyperthermia is a rare pharmacogenetic syndrome characterized by a severe hypermetabolic reaction after the administration of halogenated inhalational anesthetics or depolarizing muscle relaxants such as succinylcholine, or both. Although it is a potentially fatal disease, the rapid administration of continued doses dantrolene has drastically reduced the morbidity and mortality of the disease.

Complications from Parkinson's disease may develop over the disease course, sometimes unexpectedly, and require prompt or even urgent medical intervention. The most common are associated with aggravation of motor symptoms; serious non-motor complications, such as psychosis, orthostatic hypotension or sleep attacks, also occur. Here we review such complications, their clinical presentation, precipitating factors and management, including those related to using device-aided therapies. Early recognition and prompt attention to these critical situations is challenging, even for the Parkinson's disease specialist, but is essential to prevent serious problems., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Pharmacogenetics, the genetic influence on the interpersonal variability in drug response, has enabled tailored pharmacotherapy and emerging 'personalized medicine.' Although oncology spearheaded the clinical implementation of personalized medicine, other specialties are rapidly catching up. In anesthesia, classical examples of genetically mediated idiosyncratic reactions have been long known (e.g., malignant hyperthermia and prolonged apnea after succinylcholine). The last two decades have witnessed an expanding body of pharmacogenetic evidence in anesthesia. This review highlights some of the prominent pharmacogenetic associations studied in anesthesia and pain management, with special focus on pediatric anesthesia.

Background: Malignant hyperthermia syndrome is a hereditary pharmacogenetic disorder of skeletal muscle characterized by hypermetabolic state related to the exposure of volatile anesthetic gases or depolarizing muscle relaxants. It is an infrequent entity that occurs in genetically predisposed individuals, with a very low incidence in pediatrics (1 in 10,000-15,000 anesthetic procedures)., Case Report: We report a case of malignant hyperthermia related to exposure to sevoflurane during adenoidectomy surgery in a 6-year-old female. The patient presented with tachycardia, hypercapnia, and hyperthermia, requiring two successive doses of dantrolene sodium administration, with an adequate response to the treatment., Conclusions: Malignant hyperthermia syndrome is a rare condition in pediatric patients that should be detected in early stages since it is essential to initiate the treatment as soon as possible., (Copyright: © 2020 Permanyer.)

Malignant hyperthermia is a pharmacogenetic disorder, which is an uncommon but frequently fatal intricacy of inhalation anesthesia in man. It causes a quick rise in body temperature to highly irreversible levels, which causes death in around three of four cases. The trigger anesthetics cause an anomalous, continued ascent in myoplasmic calcium levels. Possible mechanisms by which continuous release of sodium, calcium from skeletal muscle plasma membrane and sarcoplasmic reticulum stores respectively can produce the profound hyperthermia are discussed., (© 2019 International Union of Biochemistry and Molecular Biology.)

Historically, patients who developed malignant hyperthermia had an extremely high rate of mortality. Today, if treated appropriately, patients who experience an episode of malignant hyperthermia will most likely survive. This dramatic decrease in mortality associated with malignant hyperthermia is due to several factors, including an increased understanding of the disease, improved diagnostic and monitoring equipment, and the development of lifesaving pharmacologic agents. This article presents the very likely case of acute malignant hyperthermia in a 24-year-old man with special needs, who presented for restorative dentistry under general anesthesia in the outpatient clinic of The Ohio State University's College of Dentistry.

Malignant hyperthermia is a well-known but potentially lethal disorder which is triggered by volatile anesthetics and depolarizing muscle relaxants. Early diagnosis and treatment could save lives. However, during cardiac surgery, hypothermia and cardiopulmonary bypass make the diagnosis of malignant hyperthermia extremely difficult than other surgeries. We report a case of almost-certain malignant hyperthermia, according to the clinical grading scale, in a patient undergoing on-pump coronary artery bypass grafting surgery. The patient underwent difficult weaning from cardiopulmonary bypass until intra-aortic balloon pump and temporary cardiac pacemaker had been implanted. Although dantrolene and corresponding treatments were administered recently, the patient died 12 days after surgery because of acute kidney failure and cardiac arrest. Therefore, it is important for us to previously recognize some specific signs of malignant hyperthermia during cardiopulmonary bypass to avoid severe outcomes.

This document represents a joint effort of the Society for Ambulatory Anesthesia (SAMBA) and the Ambulatory Surgical Care Committee of the American Society of Anesthesiologists (ASA) concerning the safe anesthetic care of adult malignant hyperthermia (MH)-susceptible patients in a free-standing ambulatory surgery center (ASC). Adult MH-susceptible patients can safely undergo a procedure in a free-standing ASC assuming that proper precautions for preventing, identifying, and managing MH are taken. The administration of preoperative prophylaxis with dantrolene is not indicated in MH-susceptible patients scheduled for elective surgery. There is no evidence to recommend an extended stay in the ASC, and the patient may be discharged when the usual discharge criteria for outpatient surgery are met. Survival from an MH crisis in an ASC setting requires early recognition, prompt treatment, and timely transfer to a center with critical care capabilities.