|
Causes of Malignant Hyperthermia
Malignant hyperthermia usually manifests when a patient is sedated with general anesthetics while undergoing surgery. The type of anesthetics that are known to be capable of triggering Malignant Hyperthermia are all inhalational anesthetics, which are:
Sevoflurane
This anesthetic is also known as fluoromethyl hexafluoroisopropyl ether, used in combination with desflurane. It is used with a combination of nitrous oxide and oxygen. Sevoflurane mostly is administered through mask induction because it is less irritating to mucous membranes.
Desflurane
This highly fluorinated methyl ethyl ether is used for general anesthetics in combination with sevoflurane. It is the replacement for isoflurane on humans in most parts of the western world.
Isoflurane
This is the predecessor of enflurane and was used during the early days of surgery. This halogenated ether used for inhalational anesthetics has since then been replaced with enflurane and halothane.
Halothane
This vapor is an inhalational general anesthetic. Halothane is the only available anesthetic containing the bromine atom.
Enflurane
This is a halogenated ether used for sedation during the 70's and 80's. It was created by Ross Terrel in 1963 and used for the first time in 1966. The compound is liquid at regular room temperatures but vaporizes easily.
Methoxyflurane
This was a commonly used anesthetic during the 60's and 70's. It is characterized as a halogenated ether.
Succinylcholine
This is a muscle relaxer commonly used to make endotracheal intubation possible. It is also known under the name suxamethonium and sold under the brands: Anectine and Scoline.
Early warnings for malignant hyperthermia are muscle stiffness and tachycardia. Unlike its name would suggest fever is one of the later signs of the condition developing. When undergoing surgery for longer than 20 minutes, core body temperatures of any patient should be closely monitored in order to pick up the early signs for malignant hyperthermia in time to prevent severe damages or death of the patient.
Through the years the understanding of what causes malignant hyperthermia has increased dramatically to the point where there are now approximately 80 genetic defects that are associated with the condition documented. It has also been established that malignant hyperthermia can be inherited, meaning that a person where this condition runs in the family has a 50% chance in developing it also, under the right conditions.
Currently malignant hyperthermia is treated with dantrolene which is administered intravenously. The only remedy for it is to stop using the anesthetics that trigger it. It is vital that treatment begins as soon as possible in order to prevent severe damage to the patient. Preferably treatment already starts when only suspecting malignant hyperthermia.
|
