Malignant hyperthermia is a muscle disorder categorized by hypermetabolism and is usually triggered after susceptible individuals are given volatile anesthetics and depolarizing muscle relaxants.
Susceptibility is based on an altered regulation of calcium within the skeletal muscle fiber caused by a defective calcium release channel at the sarcoplasmic reticulum. Eleven malignant hyperthermia is triggered an abnormally high release of calcium from the sarcoplasmic reticulum is initiated resulting in a hypermetabolic state, leading to typical clinical signs, such as tachycardia.
Treatment of malignant hyperthermia crisis (CHM)
The treatment of the Malignant Hyperthermia crisis must be precise, diligent, intensive and continued for several hours after the beginning of an episode.
Since 1979, the injectable dantrolene sodium drug has been available for the treatment of CHM and has contributed greatly to the dramatic decline in deaths and disability situations associated with these episodes. Dantrolene sodium is a specific medication to treat MH crises, is a muscle relaxant that acts by decreasing the release of calcium from its storage sites in the sarcoplasmic reticulum by coupling to the calcium channel. The availability of this drug is vital for centers where general anesthesia is administered.
Furthermore, in the management of CHM, it is important to have the ability to rapidly lower body temperature, manage acid-base changes, manage coagulation disorders, manage Hydroelectrolyte alterations, take the necessary measures to prevent kidney damage and avoid the circulatory collapse
Malignant hyperthermia is a hypermetabolic Musculoskeletal disorder and characterized by intracellular hypercalcemia and rapid consumption of adenosine triphosphate. This condition is triggered by exposure to 1 or more precipitating anesthetic agents including halothane, enflurane, isoflurane, desflurane, sevoflurane, and succinylcholine. The symptoms of this condition can occur in the operating room or in the Post Anesthetic Care Unit and it is characterized by sudden onset of tachycardia, tachypnea, hypertension, hypercapnia, hyperthermia, acidosis, and musculoskeletal stiffness. Dantrolene attenuates the elevation of intracellular calcium and can be administered prophylactically or immediately after the diagnosis is suspected.
Malignant hyperthermia (MH), also known as malignant fever, malignant hyperpyrexia or anesthetic fever.
Treatment
The treatment of an MH crisis requires a quick and coordinated effort of anesthesiologists, surgeons, and other assistance once the diagnosis is suspected.
Therefore, it is suggested to take a series of measures aimed at discontinuing the anesthetic procedure, to combat hypoxemia and the acidosis, control body temperature and counteract possible complications.
- Immediately interrupt anesthesia and surgery.
- Hyperventilate the patient with 100% O 2.
- Administer dantrolene from 1 to 2.5 mg/kg intravenously (IV), a dose that should be repeated every 5 or 10 minutes up to a total dose of 10 mg/kg, although it should be administered more if the symptoms persist.
- Administer Na CO 2 from 2 to 4 mEq/kg, IV, and in higher doses if suggested by arterial pH and Pa CO2.
- Control body temperature through various forms of active cooling.
- Maintain diuresis with mannitol 25 g, IV, furosemide 20 mg, IV and supply of abundant IV fluid.
- Maintain careful monitoring of the patient and continue the treatment until he is stable and later until the risk of new episodes disappears.
Although there are pre-established doses mentioned above, has not been limited yet. As there are well-documented cases where the abortive dose has reached 42 mg/kg and vice versa, where with only 1 mg/kg patients were able to leave the acute episode satisfactorily.
Summary
Malignant hyperthermia is a disorder of the skeletal muscles, characterized by intracellular hypercalcemia and rapid of adenosine triphosphate. This condition appears as a result of the exposure to 1 or more precipitating anesthetic agents, including halothane, enflurane, isoflurane, desflurane, sevoflurane, and succinylcholine.
The symptoms of this disorder may be present in the operating room or in the Unit of Postanesthetic Care and it is characterized by the sudden appearance of tachycardia, tachypnea, hypertension, hypercapnia, hyperthermia, acidosis, and musculoskeletal rigidity. Dantrolene attenuates the elevation of intracellular calcium and may be prophylactically administered as soon as the diagnosis is suspected.
