A Case Report of Acute Onset and Rapid Resolution of Atrioventricular Block After Sugammadex: Is the Autonomic System Involved?

Administering sugammadex to reverse neuromuscular blockade can cause marked bradycardia and rarely asystole. In this case, a rapid onset, biphasic heart rate response; slowing then speeding, after administering sugammadex was noted while at steady state, 1.3% end-tidal sevoflurane. On review of the electrocardiogram (ECG), the heart rate slowing coincided with the onset of a second-degree, Mobitz type I block that lasted 45 seconds. No other events, drugs, or stimuli coincided with the event. The acute onset and transient nature of the atrioventricular block without evidence of ischemia implies a brief parasympathetic effect on the atrioventricular node after sugammadex administration.