Anesthesia for a Patient with Undiagnosed Myotonic Dystrophy.

Myotonic dystrophy (DM) is an autosomal dominant genetic disorder characterized by progressively worsening loss of muscle mass and weakness. Anesthesiologists face challenges in managing these patients due to risks such as prolonged intubation and delayed recovery associated with anesthesia in such conditions. We report a case of a 40-year-old male patient undergoing open total gastrectomy under general anesthesia. After the surgery, we administered sugammadex to reverse neuromuscular blockade and confirmed the patient's spontaneous breathing. We then proceeded to extubate the patient. However, the patient experienced complications such as apnea, desaturation, and mental changes. The patient was re-intubated and transferred to the intensive care unit for ventilator support. He was diagnosed with DM by genetic test later. Poor preoperative assessment or undiagnosed DM in surgical patients can lead to severe complications. Thus, it is important to carefully check preoperative laboratory results, patient history, and physical findings.