MALIGNANT HYPERTHERMIA, Causes, Signs and Symptoms, Diagnosis and Treatment.

Medical Centric

10 Feb 202004:09

Summary

TLDRMalignant hyperthermia is a life-threatening reaction to certain anesthesia drugs, affecting 1 in 5,000 to 50,000 patients. It is often caused by mutations in genes like RYR1 and can be inherited. Symptoms include high fever, muscle rigidity, and rapid heart rate. Diagnosis involves the CHCT test and genetic testing. Treatment with dantrolene, rapid cooling, and supportive care can reduce the risk of death from 75% to 5%.

Takeaways

⚠️ Malignant hyperthermia is a severe reaction to certain anesthetic drugs used in surgery.
👥 People with malignant hyperthermia susceptibility usually appear normal until exposed to triggering agents.
❌ Malignant hyperthermia occurs in 1 in 5,000 to 50,000 cases upon exposure to anesthesia.
⚰️ Without treatment, the fatality rate is about 75%, but with treatment, it is reduced to 5%.
👨 Men are more likely to experience malignant hyperthermia than women.
🔬 The main cause of malignant hyperthermia is exposure to volatile anesthetics like halothane or muscle relaxants like succinylcholine.
🧬 Susceptibility is often caused by mutations in genes, with the RYR1 gene mutation being the most common.
🏋️‍♂️ Physical stress or heat exposure can also trigger symptoms in susceptible individuals.
🧪 Diagnosis often involves testing muscle tissue response to caffeine and halothane, or genetic testing.
💉 Treatment includes administering dantrolene, cooling the patient, and discontinuing triggering agents.

Q & A

What is malignant hyperthermia?
-Malignant hyperthermia is a severe reaction to certain drugs used as anesthesia for surgery and other invasive procedures.
Who is at increased risk for malignant hyperthermia?
-People with a malignant hyperthermia susceptibility are at increased risk.
How often does malignant hyperthermia occur?
-It occurs in one in 5,000 to 50,000 cases on exposure to anesthetic gases.
What is the fatality rate without proper treatment?
-Without treatment, the complication of malignant hyperthermia can be fatal with a risk of death about 75%.
Who is more likely to experience malignant hyperthermia, men or women?
-Men are more likely to have an episode than women.
What causes malignant hyperthermia?
-The cause is exposure to volatile anesthetics such as halothane and depolarizing muscle relaxant such as Sesenta choline in those who are susceptible.
How many forms of malignant hyperthermia susceptibility have been identified?
-Researchers have identified at least six forms of malignant hyperthermia susceptibility caused by different gene mutations.
What is the most common gene mutation associated with malignant hyperthermia?
-The most common is a mutation in the ry RI gene, which is responsible for a form of the condition known as MH s one.
How is malignant hyperthermia susceptibility inherited?
-Susceptibility is usually inherited in an autosomal dominant manner, meaning only one copy of the mutant gene is necessary for an individual to inherit the disorder.
What are the symptoms of malignant hyperthermia?
-Symptoms include a very high temperature, muscle rigidity, rhabdomyolysis, a rapid heart rate, abnormally rapid breathing, acidosis, and increased carbon dioxide production.
How is malignant hyperthermia diagnosed?
-Diagnosis is suspected by the appearance of typical symptoms following anesthesia administration. The standard procedure is the caffeine halothane contracture test (CHCT), which measures the response of muscle tissue to caffeine and halothane.
What is the treatment for malignant hyperthermia?
-Treatment options include intravenous administration of dantrolene, rapid cooling, discontinuation of triggering events, and supportive therapy directed at correcting organ dysfunction and acidosis.

Outlines

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🚑 Malignant Hyperthermia: Understanding and Risk Factors

Malignant hyperthermia is a severe reaction to certain drugs used as anesthesia during surgeries and invasive procedures. People at risk are said to have malignant hyperthermia susceptibility (MHS). Apart from susceptibility to triggering agents, affected individuals are indistinguishable from the general population. It occurs in 1 in 5,000 to 50,000 cases and can be fatal without treatment. Men are more likely to experience it than women. Causes include exposure to volatile anesthetics like halothane and depolarizing muscle relaxants like succinylcholine. It can be caused by mutations in different genes, with the most common being the RYR1 gene. Susceptibility is usually inherited in an autosomal dominant manner. Symptoms include high temperature, muscle rigidity, rhabdomyolysis, rapid heart rate, and abnormally rapid breathing. It's crucial to inform doctors of any MHS before surgery.

Mindmap

Keywords

💡Malignant Hyperthermia

Malignant hyperthermia is a severe reaction to certain anesthetic drugs used during surgery. It is characterized by a rapid increase in body temperature and muscle rigidity. The video focuses on the importance of identifying susceptibility to this condition, as it can be life-threatening if not treated promptly.

💡Susceptibility

Susceptibility refers to an individual's increased risk of developing malignant hyperthermia due to genetic factors. Those with this susceptibility are indistinguishable from the general population until they are exposed to triggering agents like anesthetic gases. The video emphasizes that knowing one's susceptibility is crucial for preventing a severe reaction.

💡Anesthetic Gases

Anesthetic gases, such as halothane, are one of the primary triggers for malignant hyperthermia. These gases are commonly used during surgery to induce unconsciousness, but for individuals with malignant hyperthermia susceptibility, they can lead to a life-threatening reaction. The video explains the importance of avoiding these gases in susceptible individuals.

💡Dantrolene

Dantrolene is the only known drug effective in treating malignant hyperthermia. It works by relaxing the muscles and reducing the dangerous rise in body temperature that occurs during an episode. The video highlights dantrolene as a crucial treatment option to prevent death in affected individuals.

💡Rhabdomyolysis

Rhabdomyolysis is the breakdown of muscle fibers, a symptom often associated with malignant hyperthermia. This condition can lead to the release of muscle contents into the bloodstream, causing complications such as kidney damage. The video mentions rhabdomyolysis as one of the severe symptoms to watch for during a malignant hyperthermia episode.

💡Autosomal Dominant Inheritance

Malignant hyperthermia susceptibility is often inherited in an autosomal dominant manner, meaning only one copy of the mutated gene is needed for the disorder to be passed down. The video explains that individuals with a family history of the condition should be tested for susceptibility, as it can be inherited.

💡Genetic Mutations

Genetic mutations are changes in the DNA that can lead to malignant hyperthermia susceptibility. The most common mutation is in the RYR1 gene, which affects calcium regulation in muscle cells. The video outlines various genetic mutations associated with different forms of the condition, stressing the importance of genetic testing.

💡Caffeine Halothane Contracture Test (CHCT)

The CHCT is a diagnostic test used to confirm susceptibility to malignant hyperthermia. It involves exposing a sample of muscle tissue to caffeine and halothane to observe its response. The video explains that this test is performed at specialized centers and is recommended for individuals with a family history of the condition.

💡Acidosis

Acidosis refers to an increase in acid levels in the blood and other tissues, which can occur during an episode of malignant hyperthermia. This condition can lead to organ dysfunction if not treated. The video lists acidosis as one of the key symptoms of malignant hyperthermia, emphasizing the need for immediate medical intervention.

💡Central Core Disease

Central core disease is a rare inherited muscle disorder that is associated with malignant hyperthermia susceptibility. The video notes that some individuals with muscle diseases like central core disease are more likely to experience malignant hyperthermia, indicating a genetic link between the two conditions.

Highlights

Malignant hyperthermia is a severe reaction to certain drugs used as anesthesia for surgery.

People with malignant hyperthermia susceptibility are usually not distinguishable from the general population.

Susceptible people are recommended to avoid potential triggers.

Malignant hyperthermia occurs in 1 in 5,000 to 50,000 cases when exposed to anesthetic gases.

Without treatment, malignant hyperthermia can be fatal, with a mortality risk of about 75%.

With proper treatment, the risk of death from malignant hyperthermia decreases to about 5%.

Men are more likely to have an episode of malignant hyperthermia than women.

The main cause of malignant hyperthermia is exposure to volatile anesthetics like halothane or depolarizing muscle relaxants.

Susceptibility can occur from mutations in various genes, most commonly the RYR1 gene.

Malignant hyperthermia susceptibility is usually inherited in an autosomal dominant manner.

The disorder may also be triggered by physical exercise or heat exposure in some cases.

Symptoms include a very high temperature, muscle rigidity, rapid heart rate, and increased carbon dioxide production.

Diagnosis can be confirmed by the caffeine-halothane contracture test (CHCT) or genetic testing.

Dantrolene is the only drug known to be effective in treating malignant hyperthermia.

Treatment also includes rapid cooling, discontinuation of triggers, and supportive therapy to address organ dysfunction.