Malignant Hyperthermia (MHS)

Malignant Hyperthermia (MHS) is a rare muscle abnormality that causes harmful reaction in a person who is given certain drugs required during surgery. It can cause fatal reaction after a dose of general anesthesia. It can also happen due to heat stroke or extreme exercise.

Symptoms

Following are the symptoms that are observed for the first time when the patient receives an anesthetic dose:

• Muscle contraction and rigidity.
• Rapid increase in body temperature; fever can go beyond 110 degree F.
• Urine color changes to dark brown.
• Muscle ache; pain in hands and legs.
• Irregular heartbeat

Some patients also show neurological symptoms like weakness or seizure accompanied by low blood pressure. These symptoms generally are noticed within an hour, after the medication is administered.

Causes

As aforementioned, if the person is having muscle abnormality and is exposed to certain medications, then malignant hyperthermia can occur. Drugs that are known to trigger this severe reaction are inhaled anesthetics that include enflurane, sevoflurane, desflurane and isoflurane. Medications such as succinylcholine, that is commonly used as a muscle relaxant at the time of surgery, can also cause malignant hyperthermia.

Treatment

The doctors must act fast so that the condition does not worsen. As soon as the symptoms are detected, the first and foremost step is to stop the anesthetic medication to prevent any further complications. The surgery should also be immediately stopped. In such cases, doctors give a medicine (Dantrolene) to stabilize the condition of the patient. Dantrolene treatment is commonly used to reduce the impact of this reaction. The drug dantrolene relaxes the muscles. Initially, dantrolene is given into the veins to improve the condition. Once the patient's condition improves, the medication is continued in pill form for a few days. If the symptoms are identified early, then the treatment will give a successful outcome.

In order to reduce the fever, you can also take the help of cooling blankets. Cooled fluids, tepid sponging, cool nasogastric lavage are used to decrease the body temperature. Other treatments include administering oxygen and monitoring the patient's conditions in an intensive care unit. If left untreated, it can lead to life-threatening complications like brain hemorrhage, internal bleeding, kidney failure and cardiac arrest.

Susceptibility

It is an inherited disorder causing muscle abnormality. If the patient has a family history of MHS, then the person has a higher chance of inheriting this defect. This disorder generally occurs mostly in children and people below 30 years.

Duration

If the treatment is given on time, symptoms will go away within a period of 12 to 24 hours. However, the damage caused by this fatal reaction can be permanent, in case the treatment is delayed.

One way to prevent this fatal reaction is by notifying the doctor about your sensitivity to anesthesia, so that he avoids using high-risk anesthetics. A number of safe, alternative anesthetics have been developed that do not trigger any reaction. Therefore, informing the anesthesiologist about your health and family history before any surgery is an absolute must.