Reviewed By: Pramod Kerkar, MD, FFARCSI

Malignant hyperthermia is a term used for a condition that triggers a reaction response to some particular drugs, which are used as anesthetics for surgery or for some other reason. Malignant hyperthermia can be fatal if not attended quickly. Malignant hyperthermia is a pharmacogenetic disorder. In most cases, it is an inherited disorder.

What Is The First Sign Of Malignant Hyperthermia?

The first visible sign of malignant hyperthermia is a severe and abnormally high production of the carbon dioxide gas. Along with this sign, there may be additional symptoms like:

  • There may be severe muscle spasms
  • A very rapid heart rate also known as tachycardia
  • Increased body temperature (hyperthermia) is one of the first signs of malignant hyperthermia
  • Rapid breathing known as tachypnea
  • Increased consumption of the oxygen gas
  • Acidosis
  • Muscle rigidity

The body temperature in malignant hyperthermia condition can rise abnormally and very dangerously to a very high level. There can be serious muscle spasm along with a very rapid heart rate.

Causes Of Malignant Hyperthermia

Malignant hyperthermia is a genetically inherited disorder. If one of the two parents or a sibling or a child has malignant hyperthermia, then there are 50% chances in a person that he may acquire this condition.

  • If other close relatives have this condition, then there is a chance of 25% that one may inherit this condition.
  • Also, it is more commonly seen in men than in women.
  • A person having this condition may not suffer from malignant hyperthermia in the first instance of surgery, but he may still remain at a risk in future.
  • In very rare cases, people show symptoms of malignant hyperthermia after very intense physical activity.

Diagnosis Of Malignant Hyperthermia

The diagnosis must be thought of in all patients who receive the triggering agents. As in most of the cases, the persons receiving the triggering drugs in the past have no events of malignant hyperthermia.

Also, those who develop malignant hyperthermia during a surgery are generally tested to find a negative history of this condition in the family.

Moreover, presence of one or two typical signs and symptoms associated with this condition must not be overlooked and prompt vigilance must be kept under all circumstances.

  • Any of the below signs and symptoms if seen in a person receiving triggering drugs or under anesthesia should be evaluated for a risk of malignant hyperthermia
  • An increase in the levels of end-tidal carbon dioxide also known as ETCO2 that does not come to normal levels even after increasing the ventilation
  • Muscular rigidity that is generalized especially when a neuromuscular blockade is administered
  • Increased heart rate also known as tachycardia which is unexplained
  • Increased respiration rate also known as tachypnea which is unexplained
  • Increased potassium (hyperkalemia) related irregular heart rate also known as arrhythmias.
  • Abnormally and dangerously increasing body temperature also known as hyperthermia.

Lab tests are then carried out to confirm the diagnosis of malignant hyperthermia. Many other factors may cause signs and symptoms similar to that of malignant hyperthermia and though the treatment for malignant hyperthermia might have been started, these conditions must not be overlooked. Some of them are mentioned below-

  • If anesthesia is given in an insufficient amount, a person may present with many of the above symptoms including tachycardia, hypertension, hyperkalemia etc.
  • If ventilation is given in insufficient quantities, a person may present with many symptoms like increase in the carbon dioxide, tachycardia, hypertension, etc.
  • Fever may be present as a result of other infections. Clinical conditions must also be considered
  • Many drugs may be responsible for development of similar signs and symptoms like that of malignant hyperthermia. This possibility must not be overlooked either.

Malignant hyperthermia is a pharmacogenetic disorder that is inherited by a person from his family members. It is a serious condition and when diagnosed, it must be emergently attended to. In absence of a prompt diagnosis and an efficient treatment it can prove to be dangerously fatal.

Also Read:

Pramod Kerkar

Written, Edited or Reviewed By:

, MD,FFARCSI

Pain Assist Inc.

Last Modified On: November 19, 2018

This article does not provide medical advice. See disclaimer

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