[Anesthetic management of a child with congenital myotonic dystrophy and perioperative hypoxia].

A 7-year-old boy with congenital myotonic dystrophy (MD) and developmental retardation underwent an emergency surgery for strangulation ileus. General anesthesia was maintained using sevoflurane and fentanyl. While intraoperative arterial blood pressure, pulse and rectal temperature remained stable, the arterial blood oxygenation gradually deteriorated during the procedure. We suspected the existence of atelectasis or some other obstructive lung lesion to be the underlying cause, and performed bronchoscopic examination which revealed a collapse of the left main bronchus. Therefore, postoperative mechanical ventilation was continued for several hours in the ICU. According to the postoperative computed tomography, the left main bronchus was sandwiched between the aortic arch and thoracic vertebra. It has been reported that MD patients have a risk of perioperative pulmonary complications, particularly in those who have severe muscular disability undergoing upper abdominal surgery. These risk factors combined with bronchial stenosis could have caused intraoperative hypoxia in our patient. We conclude that when a severe MD patient is scheduled for an upper abdominal surgery, mechanical ventilation should be considered until spontaneous recovery from muscle relaxants occurs. Also, since MD has been related to malignant hyperthermia, total intravenous anesthesia, possibly combined with regional blockade, is a preferable method of anesthesia for such patients.