Treatment of Malignant Hyperthermia without Dantrolene in a 14-year-old Boy

Correspondence To the Editor: Malignant hyperthermia (MH) is a rare but potentially fatal, inherited skeletal muscle disorder that is mostly induced by the ingestion of the depolarizing relaxant, i.e., succinylcholine or volatile anesthetics. Its incidence is reportedly 1/5000 to 1/100,000 in general anesthesia patients, and children seem to be more susceptible than adults. According to MH treatment guidelines of the Malignant Hyperthermia Association of the United States (MHAUS) and European Malignant Hyperthermia Group (EMHG), dantrolene should be administered as soon as possible in suspected case. Unfortunately, dantrolene is not readily available worldwide. Here, we reported a highly suspected MH case treated without dantrolene. We believe that physicians, especially in countries that dantrolene is not readily available, would be interested in our experiences. A 14-year-old boy with normal blood test results and vital signs, without any significant personal or family history, scheduled for the reduction of an upper right humeral fracture. General anesthesia was induced with a combination of propofol (2.5 mg/kg), sufentanil (1 μg/kg), and cisatracurium (0.15 mg/kg) and maintained with a combination of 2% sevoflurane, propofol 5 mg·kg −1 ·h −1 , and remifentanil 0.2 μg·kg −1 ·min −1. Eighty minutes after the induction of anesthesia, a slight increase in end-tidal partial pressure of carbon dioxide (P ET CO 2) was observed which was from 40 to 50 mmHg (1 mmHg = 0.133 kPa). We performed manual ventilation, the P ET CO 2 decreased, and a small elevation in airway pressure was perceived. The CO 2 absorbent was replaced, and ventilation parameters were adjusted. In the following several minutes, the P ET CO 2 hovered at 40–50 mmHg and suddenly increased to 80–113 mmHg. At the same time, a severe increase in heart rate to 185 was emerged along with a significant decrease in noninvasive blood pressure to 60/30 mmHg. Simultaneously, the boy started to run a fever. His nasopharyngeal temperature (NT) detected by an electronic temperature probe was 38.6°C and reached to 41.3°C in 5 min. A great deal of vapor and condensation water emerged in the artificial circle. An MH crisis was suspected. Unfortunately, dantrolene was unavailable in our hospital. Stop inhaling sevoflurane, high-frequency manual ventilation with pure oxygen using an amended Mapleson D system (Gale Med, Taiwan, China) was administered instantly, and a series of rescue measures as well including a radial arterial and femoral vein line, vasoactive agents (dopamine and dobutamine 5–10 μg·kg −1 ·min …