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Orphanet Journal of Rare Diseases Aug 2015Malignant hyperthermia (MH) is a pharmacogenetic disorder of skeletal muscle that presents as a hypermetabolic response to potent volatile anesthetic gases such as... (Review)
Review
Malignant hyperthermia (MH) is a pharmacogenetic disorder of skeletal muscle that presents as a hypermetabolic response to potent volatile anesthetic gases such as halothane, sevoflurane, desflurane, isoflurane and the depolarizing muscle relaxant succinylcholine, and rarely, in humans, to stressors such as vigorous exercise and heat. The incidence of MH reactions ranges from 1:10,000 to 1: 250,000 anesthetics. However, the prevalence of the genetic abnormalities may be as great as one in 400 individuals. MH affects humans, certain pig breeds, dogs and horses. The classic signs of MH include hyperthermia, tachycardia, tachypnea, increased carbon dioxide production, increased oxygen consumption, acidosis, hyperkalaemia, muscle rigidity, and rhabdomyolysis, all related to a hypermetabolic response. The syndrome is likely to be fatal if untreated. An increase in end-tidal carbon dioxide despite increased minute ventilation provides an early diagnostic clue. In humans the syndrome is inherited in an autosomal dominant pattern, while in pigs it is autosomal recessive. Uncontrolled rise of myoplasmic calcium, which activates biochemical processes related to muscle activation leads to the pathophysiologic changes. In most cases, the syndrome is caused by a defect in the ryanodine receptor. Over 400 variants have been identified in the RYR1 gene located on chromosome 19q13.1, and at least 34 are causal for MH. Less than 1 % of variants have been found in CACNA1S but not all of these are causal. Diagnostic testing involves the in vitro contracture response of biopsied muscle to halothane, caffeine, and in some centres ryanodine and 4-chloro-m-cresol. Elucidation of the genetic changes has led to the introduction of DNA testing for susceptibility to MH. Dantrolene sodium is a specific antagonist and should be available wherever general anesthesia is administered. Increased understanding of the clinical manifestation and pathophysiology of the syndrome, has lead to the mortality decreasing from 80 % thirty years ago to <5 % in 2006.
Topics: Genetic Counseling; Humans; Malignant Hyperthermia
PubMed: 26238698
DOI: 10.1186/s13023-015-0310-1 -
Missouri Medicine 2019Malignant Hyperthermia (MH) is a life-threatening pharmacogenetic disorder which results from exposure to volatile anesthetic agents and depolarizing muscle relaxants.... (Review)
Review
Malignant Hyperthermia (MH) is a life-threatening pharmacogenetic disorder which results from exposure to volatile anesthetic agents and depolarizing muscle relaxants. It manifests as a hypermetabolic response resulting in tachycardia, tachypnea, hyperthermia, hypercapnia, acidosis, muscle rigidity and rhabdomyolysis. An increase in the end-tidal carbon dioxide is one of the earliest diagnostic signs. Dantrolene sodium is effective in the management of MH, and should be available whenever general anesthesia is administered. This review also aims to highlight the genetics and pathology of MH, along with its association with various inherited myopathy syndromes like central core disease, multi-mini core disease, Native-American myopathy, and King-Denborough syndrome.
Topics: Anesthetics; Dantrolene; Humans; Malignant Hyperthermia; Muscle Relaxants, Central; Neuromuscular Depolarizing Agents
PubMed: 31040503
DOI: No ID Found -
Circulation Oct 2020This is the summary publication of the International Liaison Committee on Resuscitation's . It addresses the most recent published evidence reviewed by the First Aid... (Review)
Review
This is the summary publication of the International Liaison Committee on Resuscitation's . It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life-threatening bleeding through the use of tourniquets, hemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research.
Topics: Aspirin; Bandages; Emergency Medical Services; First Aid; Glucose; Heat Stroke; Hemorrhage; Humans; Hyperthermia; Hypoglycemia
PubMed: 33084394
DOI: 10.1161/CIR.0000000000000897 -
International Journal of Hyperthermia :... 2023The heating characteristics of water-filtered infrared-A (wIRA) radiation were investigated in two body regions of healthy humans according to the quality standards of...
PURPOSE
The heating characteristics of water-filtered infrared-A (wIRA) radiation were investigated in two body regions of healthy humans according to the quality standards of the European Society for Hyperthermic Oncology (ESHO) using an irradiance (infrared-A) of 146 W m as recommended for clinical superficial hyperthermia (HT).
METHODS
wIRA was applied to the abdominal wall and lumbar region for 60 min. Skin surface temperature was limited to ≤43 °C. Tissue temperatures were measured invasively at 1-min intervals before, during and after wIRA exposure using five fiber-optical probes at depths of 1-20 mm.
RESULTS
Significant differences between body regions occurred during the heating-up phase at depths of 5-15 mm. Thermal steady states were reached at depths ≤5 mm after exposures of 5-6 min, and ≤20 mm after 20 min. On average, the minimum requirements of ESHO were exceeded in both regions by the following factors: ≈3 for the heating rate, ≈2 for the specific absorption rate and ≈1.4 for the temperature rise. Tissue depths with ≥ 40 °C and > 41 °C were ≤10 mm, and ≤20 mm for ≤ 43 °C. The temperature decay time after termination of irradiation was 1-5 min. Corresponding temperatures were ≤42.2 °C for CEM and ≤41.8 °C for CEM, i.e., they are inadequate for direct thermal cell killing.
CONCLUSIONS
Thermography-controlled wIRA-HT complies with the ESHO criteria for superficial HT as a radiosensitizer and avoids the risk of thermal skin toxicity.
Topics: Humans; Heating; Hyperthermia; Hyperthermia, Induced; Abdominal Wall
PubMed: 37592457
DOI: 10.1080/02656736.2023.2244208 -
Ugeskrift For Laeger Mar 2023Hyperthermia is a severe complication to intake of methamphetamines due to generalised overactivation of metabolism and muscle activity combined with vasoconstriction....
Hyperthermia is a severe complication to intake of methamphetamines due to generalised overactivation of metabolism and muscle activity combined with vasoconstriction. In this case report, a patient presented to the emergency department after injection of 2 g "crystal meth", and advanced into fatal hyperthermia and organ failure in the intensive care unit. Treatment of substance-induced hyperthermia is symptomatic and reducing metabolism with benzodiazepines and actively lowering body temperature with ice packs and cold intravenous fluids are appropriate interventions. Dantrolene may be used but is still to be properly investigated.
Topics: Humans; Methamphetamine; Fatal Outcome; Malignant Hyperthermia; Hyperthermia, Induced
PubMed: 36999287
DOI: No ID Found -
The Israel Medical Association Journal... Apr 2023
Topics: Humans; Malignant Hyperthermia
PubMed: 37129134
DOI: No ID Found -
Brazilian Journal of Anesthesiology... 2023
Topics: Humans; Malignant Hyperthermia
PubMed: 36963956
DOI: 10.1016/j.bjane.2023.03.001 -
Anesthesiology Nov 1980In MH, skeletal muscle acutely and unexpectedly increases its oxygen consumption and lactate production, resulting in greater heat production, respiratory and metabolic... (Review)
Review
In MH, skeletal muscle acutely and unexpectedly increases its oxygen consumption and lactate production, resulting in greater heat production, respiratory and metabolic acidosis, muscle ridigity, sympathetic stimulation, and increased cellular permeability. The best-accepted theory is that MH is due to an inability to control calcium concentrations within the muscle fiber, and may involve a generalized alteration in cellular or subcellular membrane permeability. Episodes are predictably initiated in susceptible people and swine by potent volative anethetic agents or succinylcholine. In addition, in swine, MH is consistently triggered by excitement, apprehension, exercise, or environmental stress such as heat or hypoxia. Several genetic factors probably control the human and porcine inheritance of MH. Sympathetic involvement in MH, while controversial, is probably a response to stress that affects blood flow, heat loss, and myocardial function, rather than a direct sympathetic activation of susceptible muscle. Diagnosis is based upon extraordinary temperature and acid-base and muscle aberrations. Specific treatment is the action of dantrolene upon muscle calcium movements; sympatomatic treatment is by reversal of acid-base and temperature changes. Evaluation of affected families is guided by measurements of circulating creatine phosphokinase and by analysis of drug-induced contractures in muscle biopsy specimens. Anesthesia for susceptible patients includes thiopental, opiates, droperidol, pancuronium, nitrous oxide, and preoperative oral doses of dantrolene.
Topics: Adult; Anesthesia; Animals; Creatine Kinase; Disease Models, Animal; Humans; Legislation, Medical; Male; Malignant Hyperthermia; Muscles; Myocardium; Rabbits; Rats; Swine; Syndrome; United States
PubMed: 6999950
DOI: 10.1097/00000542-198011000-00007 -
Swiss Medical Weekly 2012Malignant hyperthermia (MH) is a subclinical myopathy, usually triggered by volatile anaesthetics and depolarising muscle relaxants. Clinical symptoms are variable, and... (Review)
Review
Malignant hyperthermia (MH) is a subclinical myopathy, usually triggered by volatile anaesthetics and depolarising muscle relaxants. Clinical symptoms are variable, and the condition is sometimes difficult to identify. Nevertheless, rapid recognition and specific as well as symptomatic treatment are crucial to avoid a lethal outcome. Molecular genetic investigations have confirmed the skeletal muscle type ryanodine receptor to be the major MH locus with more than 70% of MH families carrying a mutation in this gene. There is no screening method to test for MH, as current tests are invasive (open muscle biopsy) or restricted to MH families with known MH-associated mutations (molecular genetic testing). The prevalence of the MH trait is unknown, because the clinical penetrance after contact with triggering agents is very variable. More recently, MH mutations have been associated with rhabdomyolysis following statin therapy or with non-pharmacological triggering, such as exertional heat stroke.
Topics: Anesthesia, General; Creatine Kinase; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Malignant Hyperthermia; Rhabdomyolysis
PubMed: 22851008
DOI: 10.4414/smw.2012.13652 -
Postgraduate Medical Journal Jan 1998Malignant hyperthermia is a rare autosomal dominant trait that predisposes affected individuals to great danger when exposed to certain anaesthetic triggering agents... (Review)
Review
Malignant hyperthermia is a rare autosomal dominant trait that predisposes affected individuals to great danger when exposed to certain anaesthetic triggering agents (such as potent volatile anaesthetics and succinylcholine). A sudden hypermetabolic reaction in skeletal muscle leading to hyperthermia and massive rhabdomyolysis can occur. The ultimate treatment is dantrolene sodium a nonspecific muscle relaxant. Certain precautions should be taken before anaesthesia of patients known to be susceptible to malignant hyperthermia. These include the prohibition of the use of triggering agents, monitoring of central body temperature and expired CO2, and immediate availability of dantrolene. In addition, careful cleansing of the anaesthesia machine of vapours of halogenated agents is recommended. If these measures are taken, the chances of an MH episode are greatly reduced. When malignant hyperthermia-does occur in the operating room, prompt recognition and treatment usually prevent a potentially fatal outcome. The most reliable test to establish susceptibility to malignant hyperthermia is currently the in vitro caffeine-halothane contracture test. It is hoped that in the future a genetic test will be available.
Topics: Anesthesia; Anesthetics, Inhalation; Caffeine; Central Nervous System Stimulants; Dantrolene; Halothane; Humans; Malignant Hyperthermia; Muscle Relaxants, Central
PubMed: 9538480
DOI: 10.1136/pgmj.74.867.11