Facts About Malignant Hyperthermia




MH Effects in Surgery

MH complications include a rise in heart rate, extreme temperature elevation, muscle breakdown and changes in body chemistry that can lead to excessive bleeding and the failure of organs and other body systems. The reaction can occur during any part of a procedure under general anesthesia or even in the recovery room, and in any surgical setting from office and ambulatory centers to hospitals. It can be treated with dantrolene sodium if the case is identified and treatment is administered very early in the onset of the condition. Unfortunately, a few cases of malignant hyperthermia can result in death even if proper treatment is administered.

Detecting MH

A very specialized muscle biopsy test, only available at a few institutions, is the most accurate test for malignant hyperthermia susceptibility. However, DNA testing can help provide answers for people who suspect they might be at risk. You can be assured that MH is an extremely uncommon condition, and you anesthesiologist and other surgical team members are well-trained for adverse reactions that can occur during procedures.

Patient Responsibility

To be sure you receive the highest level of care no matter what happens in the OR, it is critical that you request an anesthesiologist’s presence for any procedure involving anesthesia. This ensures the person giving you anesthesia is a fully trained licensed physician, and you know you have the most highly trained professional physician at your side to manage any complications that may arise.

Prior to undergoing general anesthesia for surgery, patients concerned about malignant hyperthermia inform their anesthesiologist of any personal or family history of malignant hyperthermia, or adverse reactions to anesthetics. You also may ask if a supply of dantrolene is available in the facility where surgery will take place and whether treatment protocols are also available.

MH Patient Registry

While 95 percent of patients who experience malignant hyperthermia reactions survive it, the ASA-MHAUS partnership still needs the public’s help to build a database of patients who are already aware they have the gene mutation that leads to malignant hyperthermia. Since its formation in 1981, MHAUS has been working through its growing member network of patients that are MH-susceptible and their family members, as well as anesthesiologists health care providers to educate other members of the medical community and the public regarding the risks MH can unexpectedly pose in conjunction with some of the most commonly used anesthetics in hospital operating rooms, dental offices and surgical centers. Please visit MHAUS for more information on the database.

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