Let's learn about Malignant Hyperthermia, a dangerous reaction to anesthesia during surgery.

If you or someone in your family ever has to undergo surgery, you'll be given anesthesia before it, right? Simply put, it puts us completely to sleep. But for some people, some of the medications used for this anesthesia can cause an unimaginably severe, even life-threatening reaction. Today we're talking about malignant hyperthermia , a dangerous but treatable condition if detected early.

What is Malignant Hyperthermia?

Simply put, Malignant Hyperthermia is a genetic condition. This means that it is hereditary. When a person with this condition is exposed to certain types of anesthesia during surgery, their body reacts very severely. This is a life-threatening emergency. But the most important thing here is that this does not happen with every drug used for anesthesia during surgery. Only a very limited number of drugs cause this reaction. Moreover, if it is identified, it can be treated quickly. Most of the time, a person does not know that they have a gene mutation related to this in their body. Because they do not show any symptoms in normal life. The problem only arises when that particular anesthetic drug enters the body.

Who is more at risk?

This risk is mainly present if someone in the family has this condition.

• Family history: If a close relative of yours - a mother, father, brother, sister, or child - has had malignant hyperthermia, you are at increased risk. Therefore, if you ever have surgery, it is important to tell the anesthesiologist about this family history .
• Certain muscle diseases: Even if no one in your family has had this problem, people with certain rare muscle diseases are at higher risk. For example:
• Central core disease
• Multiminicore disease
• King-Denborough syndrome
• STAC3 disorder

These are very rare conditions, but if you or someone in your family has one, it is important to let your doctor know.

How common is this condition?

This is actually not a very common condition. According to statistics, this condition occurs in about one in 100,000 surgeries in adults. Among young children, this number is slightly higher, that is, one in 30,000 surgeries. It is also noteworthy that half of the patients identified are under the age of 19. However, scientists think that people with a genetic predisposition to this may be more common in society. This is because, even if they have the gene, if they are not exposed to anesthetic drugs that cause that reaction throughout their lives, this condition will never arise.

What are the symptoms of this?

These symptoms can occur during surgery or shortly after surgery while you are recovering. If you have these symptoms while you are asleep and under anesthesia, you will not feel them. But your anesthesiologist will notice them. They will monitor your vital signs very carefully throughout the surgery. So they will start treatment as soon as they notice these symptoms.

Why is this happening? What is the reason?

People who are prone to Malignant Hyperthermia have a genetic change, that is, a genetic mutation, in some proteins in their muscle cells. Imagine that our muscle cells have calcium stored inside them. The release of this calcium is controlled by something like a gate. When a normal person is given anesthetic drugs, this gate works in a controlled manner. This causes the muscles to contract and tighten, the body's metabolism starts to speed up, and the body temperature rises dangerously. Eventually, the muscle cells die, and large amounts of substances such as potassium accumulate in the blood. Other serious symptoms occur because of these reasons.

What drugs cause this reaction?

This condition is caused mainly by two groups of drugs.

• Inhaled anesthetics:
• Halothane
• Desflurane
• Sevoflurane
• Isoflurane
• Intravenous medications :
• Succinylcholine (this is a fast-acting muscle relaxant)

How do you identify and confirm this?

Detection during surgery

It is often diagnosed during surgery. If you don't know you have this condition, neither will your anesthesiologist. But he or she will be monitoring you throughout the surgery and may suspect malignant hyperthermia if they notice the following changes:

• Increased heart rate for no reason.
• Rapid rise in body temperature .
• Increased amount of carbon dioxide emitted.
• Muscle stiffness.

Anesthesiologists are trained to recognize these changes quickly, so they can begin treatment quickly.

Is it possible to know in advance whether there is a risk?

If you suspect you have this risk because of your family history, there are several special tests to confirm it.

• Caffeine Halothane Contracture Test (CHCT): This involves taking a very small piece of your muscle (muscle biopsy) and exposing it to halothane gas and caffeine in a laboratory. The way the muscle piece reacts can be used to determine whether you are predisposed to this condition.
• Genetic testing: This test, which involves taking a blood sample, can detect genetic mutations (e.g., RYR1, STAC3, CACNA1S) associated with Malignant Hyperthermia.

But these tests are a bit expensive, and they are not available everywhere in Sri Lanka. Therefore, if you need to have emergency surgery and someone in your family has this condition, doctors will not wait for the tests and will only use safe anesthetics that will not cause this reaction in you.

How is it treated?

The main and life-saving drug given in the event of malignant hyperthermia is dantrolene . As soon as the anesthesiologist suspects this condition, they immediately administer this drug intravenously. At the same time,

• The anesthetic causing the reaction is immediately stopped.
• The surgeon will be notified and the surgery will be completed as soon as possible.
• To reduce high body temperature , cold IV fluids are given into the veins, and the body is cooled with things like ice packs.
• Provides oxygen.
• Treats heart rhythm disorders.

Once the condition is under control, you will be kept in the intensive care unit (ICU) for at least a day, where the medical team will monitor you. During this time, they will perform more blood tests and provide additional treatment as needed.

What will the situation be like? What are the complications?

If the medical team diagnoses this condition quickly and treats it correctly, a full recovery is possible. The complications that can arise from this are:

• Muscle damage.
• Kidney failure.
• Liver failure.
• Bleeding.
• Cardiac arrest.
• Seizures.
• Going into a coma.
• Death.

Malignant Hyperthermia is a condition that is often fatal if left untreated. Even with proper treatment, the mortality rate is between 3% and 5%.

Can this be prevented?

Yes, it can be prevented! The best way to do this is to be aware of your risk to yourself and your doctor. If you know that you have a genetic mutation related to this, or if you know that someone in your family has this condition, you should tell the anesthesiologist before surgery. Then when he gives you anesthesia, he will use completely safe drugs instead of those risky drugs. Then that dangerous reaction will not occur. Many people find out that they have this risk only after it happens to them. That is why it is so important to know your family medical history. Malignant Hyperthermia, anesthesia, surgery, anesthesia reaction, genetic disease, dantrolene, family history, surgery safety, anesthesia complications, genetic diseases