The case seems like a routine outpatient procedure. The patient, a seemingly healthy 38-year-old male, is administered a general anesthetic and the surgeon begins operating. Soon after the procedure begins, however, the patient's vital signs start to change and his end tidal carbon dioxide level elevates at an alarming rate. Fortunately, emergency intervention saves the patient's life, but he sustains acute renal failure. It is later learned that the patient was genetically disposed to malignant hyperthermia (MH), and the event could have been avoided by selecting a different anesthetic technique that did not involve a triggering inhalational agent.

While incidents like these still do happen, it is possible to minimize the chances that they will occur in your facility with an MH pre-op screening regimen. If screening fails and a patient exhibits symptoms of MH, administering dantrolene quickly and effectively can greatly improve the final outcome. Many patients, however, receive anesthesia without ever having been properly screened for MH. Part of that is due to the general lack of understanding about this potentially fatal condition. Here, we'll try to remedy that by telling you what you need to know about the causes and treatment of MH.

A profile of malignant hyperthermia
Although exact statistics are hard to obtain, about one in 30,000 patients who receive general anesthesia will have an MH reaction. In the past, patients who experienced an episode of MH died about 80 percent of the time, but MH research and treatment have improved immeasurably over the last 30 years. Today, through better monitoring (a rise in end tidal CO2 is often the first warning sign of an episode of MH), dantrolene treatment, and other emergency intervention measures, the death rate has decreased to about seven percent in institutions that have dantrolene on hand and know how to use it.

Immediate emergency intervention isn't always successful, however