malignant hyperthermia in pediatric patient case report

There are no case reports of malignant hyperthermia in pediatric patients treated on cardiopulmonary bypass (CPB). We report the case of a 10-year-old boy undergoing aortic valve replacement. The patient developed progressive tachycardia and hypercarbia.

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What is malignant hyperthermia and what are the symptoms?

Malignant hyperthermia is a pharmacogenetic disorder. It manifests as a hypercatabolic skeletal muscle syndrome linked to inhaled volatile anesthetics or depolarizing muscle relaxants. Its clinical signs and symptoms are tachycardia, hyperthermia, hypercapnia, acidosis, muscle rigidity, rhabdomyolysis, hyperkalemia, arrhythmia and renal failure.

What is the infusion rate for pediatric malignant hyperthermia?

PEDIATRIC MALIGNANT HYPERTHERMIA 7 The patient’s anesthetic depth was maintained with a propofol infusion that was infused at a rate of 140 mcg/kg/min for the duration of the surgical procedure. An additional dose of fentanyl 10 mcg was administered during the procedure, for a total dose of 30 mcg of fentanyl.

Which disorders are included in the pediatric malignant hyperthermia 22 assessment?

PEDIATRIC MALIGNANT HYPERTHERMIA 22 assessment. These disorders include Central Core Disease, including the subsets of multiminicore myopthay and minicore myopathy, as well as King-Denborough syndrome. It is important to note that there is not an increased risk of MH in patients that have Duchenne or

How do you assess malignant hyperthermia after a MH event?

PEDIATRIC MALIGNANT HYPERTHERMIA 20 hours after the MH event to ensure the patient has stabilized. Signs that the patient is stabilizing will include a decrease in EtCO 2, a stable heart rate with a normal rhythm, and the resolution of hyperthermia and muscular rigidity (MHAUS, 2019).

What is the incident rate of malignant hyperthermia in pediatric patients?

Malignant hyperthermia is a rare anesthetic event triggered by succinylcholine and/or volatile anesthetics, resulting in a hypermetabolic state with a high mortality rate of 80–90% [1]. The incidence of MH is approximately 1 per 15,000 in pediatric patients if left untreated [2].

How many cases of malignant hyperthermia are there?

Malignant hyperthermia occurs in 1 in 5,000 to 50,000 instances in which people are given anesthetic gases.

What do you do in case of malignant hyperthermia?

Immediate treatment of malignant hyperthermia includes:Medication. A drug called dantrolene (Dantrium, Revonto, Ryanodex) is used to treat the reaction by stopping the release of calcium into muscles. ... Oxygen. You may have oxygen through a face mask. ... Body cooling. ... Extra fluids. ... Supportive care.

What is the most common cause of malignant hyperthermia?

The affected gene is most commonly inherited, usually from one parent who also has it. Less often, the affected gene is not inherited and is the result of a random gene change. Different genes can cause MHS . The most commonly affected gene is RYR1.

What are risk factors for malignant hyperthermia?

Malignant hyperthermia is a life-threatening, but treatable reaction to certain anesthesia medications. It's caused by an inherited gene mutation (change) that affects your muscles. If you have a biological parent or relative who has the mutation, you're at greater risk for experiencing malignant hyperthermia.

How is malignant hyperthermia diagnosis?

The diagnosis is based upon clinical signs (eg, hypercapnia, tachycardia, muscle rigidity, rhabdomyolysis, hyperthermia, and arrhythmia) and associated laboratory abnormalities (eg, respiratory and possibly metabolic acidosis, hyperkalemia, elevated creatine kinase, serum and urine myoglobin) (table 4).

What are the symptoms and complications of hyperthermia?

What are the symptoms of hyperthermia?Blurred vision.Dizziness.Fast breathing or heart rate.Fatigue.Headache.Light-headedness or syncope (fainting).Low blood pressure.Muscle aches or cramps.More items...•

What drugs trigger malignant hyperthermia?

According to the Malignant Hyperthermia Association of the United States (MHAUS), the following agents approved for use in the U.S. are known triggers of MH: inhaled general anesthetics, halothane, desflurane, enflurane, ether, isoflurane, sevoflurane, and succinylcholine.

What is the earliest and most sensitive indicator of an acute malignant hyperthermia crisis?

The earliest signs are tachycardia, rise in end-expired carbon dioxide concentration despite increased minute ventilation, accompanied by muscle rigidity, especially following succinylcholine administration. Body temperature elevation is a dramatic but often late sign of MH.

What is the pathophysiology of malignant hyperthermia?

Malignant hyperthermia is caused by a genetic abnormality of calcium channels within skeletal muscle. Many channels are suspected to be possible locations for this abnormality; however, only the RYR1 and CACNA1S subunits have been demonstrated to have alterations related to MH (Rosenberg et al., 2015).

What is a hypermetabolic reaction?

disorder that is triggered by commonly used anesthetic gases and succinylcholine. If not prepared for, recognized, or swiftly diagnosed, this hypermetabolic reaction . can be fatal for the pediatric patient. Purpose:To review the genetic component of this inherited disorder, as well as the current .

Is MH more common in males or females?

MH is thought to affect males more than females, and is also more common in . children under the age of 15. In addition, the incidence of MH is higher in the French, . Scandinavian, and Japanese populations, though every ethnicity may be affected (Mullins, 2017).

What is malignant hyperthermia?

Malignant hyperthermia is a rare pharmacogenetic disorder triggered by depolarizing muscle relaxant and potent volatile anesthetic agents. An MH crisis is an emergency and life-threatening event requiring early recognition and prompt management. Dantrolene is the specific antagonist of MH.

What is the mortality rate of malignant hyperthermia?

Malignant hyperthermia is a rare anesthetic event triggered by succinylcholine and/or volatile anesthetics, resulting in a hypermetabolic state with a high mortality rate of 80–90% [ 1.

What is malignant hyperthermia?

Malignant hyperthermia is a pharmacogenetic disorder. It manifests as a hypercatabolic skeletal muscle syndrome linked to inhaled volatile anesthetics or depolarizing muscle relaxants. Its clinical signs and symptoms are tachycardia, hyperthermia, hypercapnia, acidosis, muscle rigidity, rhabdomyolysis, hyperkalemia, arrhythmia and renal failure. Mortality without specific treatment is 80% and decreases to 5% with the use of dantrolene sodium.

How common is MH?

The incidence of MH is 1/50 000 to 1/250 000 in adults and 1/15 000 in children. The actual prevalence is difficult to define because there are patients with no or mild clinical reactions. In addition, the penetrance of the inherited trait is variable and incomplete (1,2).

What is MH in pharmacogenetics?

MH is a pharmacogenetic alteration that manifests as a hypermetabolic response after exposure to inhaled anesthetics (isoflurane, halothane, sevoflurane, desflurane and enflurane), and muscle relaxants such as succinylcholine (1), although it can also be produced by heat, infections, emotional stress, statin therapy and strenuous exercise (3). This reaction occurs in individuals with a certain genetic predisposition. Since susceptible patients do not present phenotypic alterations before anesthesia, it is impossible to diagnose them before exposure or before specific tests are performed.

What is the ryr1 isoform?

There are three isoforms that are variably distributed in tissues, with the RYR1 isoform predominating in skeletal muscle. In the case of our patient, the mutation described above is associated with a missense-type change that predicts the substitution of an amino acid leucine for valine at position 2286 of the protein.

What is the dominant gene in MH?

MH has an autosomal dominant pattern of inheritance. Most of the cases described are due to mutations in three genes: RYR1 (ryanodine receptor type 1), CACNS1S (dihydropyridine receptor), and STAC3. It is estimated that 70% of cases are caused by mutations in the RYR1 gene (1,11,12,13). As discussed above, our patient was heterozygous for the RYR1 gene mutation.

How much mortality is there without treatment?

Mortality without treatment amounts to 80%, decreasing to 5% with supportive measures and effective treatment, which consists of the suspension of halogenated agents, hyperventilation with 100% O2and the administration of dantrolene sodium (DS), a muscle relaxant that inhibits the release of Ca++from the ER by acting on RYR1 (2,8,9).

How long did the patient stay in the ICU after the crisis?

The patient had a subsequent good evolution, allowing withdrawal of sedation and extubation at 24 hours. He was discharged from the ICU 48 hours after the crisis, with adequate blood glucose levels.