Sugammadex Associated Persistent Bradycardia

Sugammadex is a safe selective relaxant binding agent, composed of modified cyclodextrin molecules. It especially has a selectivity for neuromuscular blocking agents (NMBAs) of steroid composition, such as rocuronium and vecuronium. In this paper, we present a case where intravenous (iv) sugammadex has been applied and subsequently persistent bradycardia has developed. A 56-year-old male patient (weight 77 kg, height 163 cm) was scheduled for ureterorenoscopy because of a stone in the upper part of ureter. Preoperative examination showed possible difficult intubation (mallampati 3). There are no known heart diseases and no history of any drug use. The electrocardiography was in normal sinus rhythm, and the blood biochemistry was normal. (WBC: 8.47 K/mm3; Hb: 14.3 g/dL; Na: 135 mEq/L; K: 3.9 mEq/L; BUN: 41 mg/dL; Creatin: 0.69 mg/dL).When the operation ended, We monitored neuromuscular block level with a neuromuscular monitoring device (TOFWatch S). At the end of the operation, 200 mg sugammadex (Bridion 200 mg/2 mL, MSD) was administered to the patient through iv injection. Approximately 2 minutes following the administration, the patient developed sinusoidal bradycardia (pulse 35 beats/min). We believe that cardiac side effects may be observed following sugammadex administration and that atropine-resistant bradycardia may also develop.