Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024591 (malignant hyperthermia)
 2,353 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the dog, creatine kinase (CK) is mostly present in the skeletal muscles, myocardium, brain and intestine. The MM isoenzyme predominates in muscles and myocardium. In plasma, reference values depend on the technique used and CK-MB accounts for about 30-45% of total CK activity. Sex has no influence on plasma CK activity, which is higher in young dogs than in adults. Plasma CK is elevated after physical exercise. After its release from the cells, CK reaches the plasma mostly via the lymphatic route and then remains in the plasma compartment. It is rapidly cleared with a half-life of about 2 hours. Muscle diseases are the main source of plasma CK elevations: inherited myopathies, malignant hyperthermia, hypothyroidism, vitamin E-selenium deficiency, prolonged decubitus, intramuscular injections, surgery, etc. Plasma CK is also increased in experimental myocardial infarction, for which the dog is an interesting model, allowing quantification of the damage by measuring the total CK activity released.
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PMID:Creatine kinase in the dog: a review. 820 15

We report on the occurrence of cardiac arrests within a few minutes following succinylcholine in 9 children, all of whom were later shown to have occult neuromuscular disease. Five of the children did not survive the catastrophic event. The anaesthetist in most cases, when discussing premedication, got the impression that the patients were in good health; just in 2 children were there indications of myopathy. Myopathic children coming to surgery and anaesthesia are rare. In these cases the administration of succinylcholine is contraindicated. But the anaesthetist must be aware of the fact that a small number of paediatric patients with unknown/subclinical myopathies might be referred to him. In these cases, without warning muscle rigor, bradycardia and hyperkalemia cardiac arrest may develop within minutes following administration of succinylcholine. The anaesthetist must be prepared for such a challenging event--particularly mentally. Misinterpretation of the symptoms as signs of malignant hyperthermia should be excluded. Resuscitation must start without delay and must continue for more than 30 minutes. Therapeutic attempts to lower extracellular potassium with glucose and insulin must fail for pharmacokinetic reasons. Therapy with intravenous calcium under control of the e.c.g. seems to be the only rational approach to the problem. It is suggested that in every healthy child coming to anaesthesia the physician should consider whether relaxation could not be achieved by other agents. Succinylcholine may well be defined as a "membrane poison"--especially considering the efflux of potassium, myoglobin and creatine kinase from the intracellular space into the bloodstream. The answer to the question asked in the title must therefore be: definitely--yes.
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PMID:[Should the use of succinylcholine in pediatric anesthesia be re-evaluated?]. 836 12

We have examined the phenotypic expression of several parameters associated with malignant hyperthermia (MH) susceptibility in three groups (homozygous normal, homozygous abnormal and heterozygous) of Yorkshire/Duroc swine genotyped by a mutation in the ryanodine receptor. Subgroups of homozygous abnormals were classified further by the appearance or absence of muscle rigidity on prolonged in vivo challenge with halothane and suxamethonium. Four swine heterozygous for the proposed MH mutation were indistinguishable from five homozygous normal swine in temperature, heart rate, lactate concentrations, base excess and pH determined during the prolonged halothane and suxamethonium challenge. Resting creatine kinase concentrations, the in vivo barnyard challenge, the in vitro contracture response of skeletal muscle to 3% halothane and the threshold for Ca(2+)-induced Ca2+ release were also similar for subgroups of homozygous normals and heterozygotes. Therefore, inheritance of only one allele carrying the defect in the ryanodine receptor does not significantly alter phenotypes associated with MH susceptibility in this strain of swine. As four swine homozygous for the proposed MH defect did not exhibit rigidity and three of these had no other signs of MH on prolonged halothane and suxamethonium challenge, we conclude that the reported mutation in the ryanodine receptor may be necessary, but is not sufficient, for consistently eliciting the malignant hyperthermia syndrome. These findings suggest that a modulator of the syndrome may explain variability within individuals in human MH.
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PMID:Phenotypes associated with malignant hyperthermia susceptibility in swine genotyped as homozygous or heterozygous for the ryanodine receptor mutation. 839 25

We report two boys aged 4 and 10 months who suffered cardiac arrests after induction of anaesthesia. Both infants had no personal or family history of myopathy. In both cases anaesthesia was induced by inhalation with halothane and N2O/O2 (70/30). To facilitate tracheal intubation both were given succinylcholine after the administration of atropine. The 4-month-old developed muscle rigidity and cardiac arrest occurred immediately after tracheal intubation. Resuscitation was unsuccessful. Laboratory findings during resuscitation showed elevated serum potassium levels of more than 10 mmol/l and serum creatine phosphokinase 17.700 IU/l. Histopathologic examination of the skeletal muscle revealed congenital muscular dystrophy. In the older boy no muscle contractures were noted after administration of succinylcholine. He developed bradycardia that progressed to asystole 15 min after induction of anaesthesia. After 1 h of resuscitation a sinus rhythm could be established. The boy developed myoglobinuria and his serum creatine phosphokinase reached a maximum level of 45,000 IU/l on the 2nd day. The child survived and made a complete recovery. Two months later a muscle biopsy taken from the quadriceps showed marked muscular dystrophy. Duchenne's muscular dystrophy could be excluded. The most likely underlying reasons for these complications are discussed: anaesthesia-induced acute rhabdomyolysis or malignant hyperthermia.
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PMID:[Anesthetic-induced heart arrest. A case report of 2 infants with previously unrecognized muscular dystrophy]. 844 72

A 6-year old female child received succinylcholine (1 mg.kg-1) and isoflurane (concentrations of 1.5-2 percent) and developed at the end of surgery a hypermetabolic syndrome suggestive of malignant hyperthermia (MH) with masseter muscle spasm, muscle rigidity, tachypnea, systolic hypertension (140 mm Hg), tachycardia (205 beats.min-1), hypercarbia (end expiratory CO2 71 mmHg), and an increase in body temperature (39.2 degrees C). The child responded well to therapy which included cooling, hyperventilation with pure oxygen and dantrolene administration. However, blood creatine kinase and myoglobin elevations were moderate (respectively 375 IU.L-1 and 114 micrograms.L-1) and an in vitro halothane and caffeine contracture test was negative. Differential diagnostic proposals are discussed and compared to the clinical incident.
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PMID:Malignant hyperthermia suggestive hypermetabolic syndrome at emergence from anesthesia. 871 51

Malignant hyperthermia (MH) is a naturally occurring disease of stress-susceptible (SS) pigs subjected to triggering agents or stress. MH is characterized by accelerated muscle metabolism and hyperthermia due to abnormally increased myoplasmic Ca2+ levels. Dantrolene is used for the treatment of MH and acts by reducing the myoplasmic Ca2+ levels. Muscle lesions can be induced by experimental restraint stress in SS pigs and are suspected to be caused by increased myoplasmic Ca2+ levels. This experiment was performed in order to study if stress induced muscle lesions could be reduced by dantrolene. Nine SS pigs were exposed to experimental restraint stress provoked by a 12 min intravenous (i.v.) infusion of the depolarizing myorelaxant succinylcholine. Five pigs were orally dosed with dantrolene (5 mg/kg), twice, about 24 and 5 h before the stress (group A). The other four pigs were treated with a single i.v. infusion of dantrolene (5 mg/kg), 30 min before stress (group B). The animals were necropsied approximately 48 h after the stress and 24 skeletal muscles were examined macro- and microscopically. No clinical signs of MH occurred during the experiment. The required dose of succinylcholine was higher in group B (0.08 mg/kg/min) than in group A (0.03 mg/kg/min) indicating decreased sensitivity to succinylcholine in SS pigs after i.v. treatment with dantrolene. The pigs in group A, but not in group B showed slightly increased serum levels of creatine kinase (CK) and aspartate aminotransferase (ASAT) at time of necropsy. A significant reduction in acute muscle lesions was observed in both groups, especially in group B, when compared with SS pigs subjected to restraint stress, but not treated with dantrolene. The muscle lesions induced by the stress model are considered to be induced by increased myoplasmic Ca2+ levels since they can be reduced by dantrolene treatment.
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PMID:The reduction of skeletal muscle lesions after experimental stress in stress-susceptible pigs protected with dantrolene. 882 90

First described in 1960, malignant hyperthermia (MH) is a relatively rare disorder of muscle metabolism triggered by specific anesthetic agents and presenting as a rapidly evolving intraoperative crisis. The syndrome is more prevalent among children (1/15,000 exposures to anesthesia) than adults (1/50,000 exposures), but has not been thought to occur in children younger than 1 year of age. This is a case report of a 3-month-old, 4.85 kg white male infant who developed MH while undergoing repair of a right inguinal hernia. The case is unique not only with respect to the age of the patient but also with the extremely elevated creatine phosphokinase (CPK) 13 hours postoperatively.
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PMID:Malignant hyperthermia in a 3-month-old infant: a case report. 887 Apr 51

A 13-year-old boy presenting for correction of bat ears was anaesthetised with thiopentone and suxamethonium, the administration of which was followed by jaw spasm, poor peripheral perfusion (without cyanosis) and marked tachycardia. The procedure was abandoned, dantrolene and Ringer lactate IL were given intravenously and the patient regained consciousness 1 h later. Levels of serum myoglobin, urinary myoglobin and creatine kinase were followed until they returned to normal. Despite a peak serum myoglobin of 58.000 micrograms.l-1 and peak urinary level of 446,000 micrograms.l-1, no renal impairment occurred. Subsequent testing for susceptibility to malignant hyperthermia proved positive for the patient and four other members of the family.
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PMID:Serum and urinary myoglobin following an aborted malignant hyperthermia reaction. 898 72

In 1992, the Malignant Hyperthermia Association of the United States and The North American Malignant Hyperthermia Registry received reports of cardiac arrest in apparently healthy children given succinylcholine. Using data from 1990 to 1993, this study analyzes: (1) etiology of all reported pediatric arrests and (2) whether survival was associated with certain patient or treatment variables. We reviewed retrospectively all reports of pediatric (age < 18 years) arrests occurring within 24 hours of anesthesia. Etiology of arrests and presence of myopathy were determined. Twenty-five patients (92% male, median 45 months old) arrested; 23/25 (92%) were scheduled for minor surgery. Before receiving a potent inhalational anesthetic (92%) and/or succinylcholine (72%), these patients were evaluated by the anesthesiologist as being healthy with no personal or family history of myopathy. Serum potassium during arrest was measured in 18/25 (72%) patients; hyperkalemia (mean [K+] = 7.4 +/- 2.8, median 7.5 mmol/L) was detected in 13/18 (72%) patients. Postarrest resuscitations lasted a median of 42 minutes (range 10-296). Ten (40%) patients died, 1 (4%) is vegetative, and 14 (56%) returned to baseline neurologic function. A previously unrecognized Duchenne dystrophy (n = 8) or unspecified myopathy (n = 4) was diagnosed in 12 (48%) patients. Eight of these 12 patients' arrests were associated with hyperkalemia. Ten (40%) patients had no postarrest evaluation to exclude occult myopathy. No patient or treatment variables were statistically associated with survival. We conclude that, whenever possible, pediatricians should evaluate their patients (especially male infants and children) preoperatively for the presence of occult myopathy. During perianesthetic resuscitations, the pediatric advanced life support protocol should be modified to detect and treat hyperkalemia, a potentially reversible state even after prolonged resuscitation efforts. Following anesthetic deaths, pathologists should examine body fluid electrolytes and skeletal muscle for myopathy and dystrophin. If a preanesthetic creatine kinase screen for myopathy in male patients and restrictions on succinylcholine had been used, 64% of arrests and 60% of deaths might have been prevented. A formal prospective risk/benefit analysis for preventive measures is needed.
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PMID:Hyperkalemic cardiac arrest during anesthesia in infants and children with occult myopathies. 900 42

Binge drinking of alcohol, cocaine overdose, or overexertion can lead to rhabdomyolysis characterized by elevated creatine kinase (CK) and myoglobin in the serum, myoglobinuria, and muscle tenderness. Our previous studies showed that ethanol, cocaine, and electrical stimulation enhanced the leakage of CK from isolated soleus and extensor digitorum longus (EDL) muscles of rat. Dantrolene sodium was reported to reduce the muscle damage and elevated serum CK levels in exercised rats. The present study was aimed at testing whether dantrolene can reduce the enhanced leakage of CK from isolated rat soleus and EDL muscles caused by ethanol, cocaine, and electrical stimulation. After 4-hr incubation in oxygenated physiological solution at 37 degrees C, the mean leakage of CK was 1.56 units/mg of muscle in soleus and 0.89 units/mg in EDL. Ethanol at 0.2% increased the leakage of CK by 47% (p < 0.05) in soleus and by 26% in EDL. Cocaine at 1 mM increased the leakage of CK by 55% (p < 0.05) in soleus and by 27% in EDL. Electrical stimulation at 1 Hz for 4 hr increased the mean leakage of CK by 100% (p < 0.05) in soleus and 127% (p < 0.05) in EDL. Dantrolene sodium reduced the enhanced leakage of CK caused by ethanol, cocaine, and electrical stimulation significantly in soleus and slightly in EDL. Dantrolene may involve myoplasmic free Ca2+ in these beneficial effects as in malignant hyperthermia, and may be useful in the treatment of rhabdomyolysis associated with acute alcoholic myopathy, cocaine overdose, and overexertion.
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PMID:Dantrolene sodium reduces the enhanced leakage of creatine kinase caused by ethanol, cocaine, and electrical stimulation in isolated fast and slow muscles of rat. 904 74


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