Dantrolene sodium and management of malignant hyperthermia.

Malignant hyperthermia (MH) is an inherited muscle disorder suffered by patients who undergo a stressful situation or acute trauma or who have been given certain anesthetic agents. 1,2 MH has been called the most common cause of anesthesiarelated death in North America, contributing a large percentage of the 15,000 to 20,000 of such deaths recorded annually.3 The 53% mortality rate of today compares favorably with the 90% rate in 1960, but it is still high.4.5 Though not confined to one specific age group, MH is most prevalent in young healthy patients who have a large muscle mass. Many orthopedists have found that patients who demonstrate weakness, cramping of extremities, twitching, and intolerance of exercise during hot weather are susceptible to developing MH. Many of the patients studied were found to have underlying musculoskeletal problems, such as kyphosis, scoliosis, or recurrent dislocation of joints.5 Mental or phys-