Reflex-Mediated Bradycardia and Asystole During Skull Base and Parapharyngeal Surgery: A Three-Case Series Highlighting Anatomical Predictability.

Intraoperative bradycardia and asystole during cranial neurovascular surgery are often regarded as unexpected events. In clinical practice, however, these episodes may occur during manipulation of specific cranial nerve-rich anatomical regions, suggesting that the risk may be anticipated and clinically actionable. We report three patients who developed suspected reflex-mediated cardioinhibitory events during surgery involving the jugular foramen, pericarotid skull base, and parapharyngeal space. The events occurred during operations involving regions in which glossopharyngeal or vagal pathways may be vulnerable, although the exact triggering structure could not be confirmed in all cases. Severity ranged from transient bradycardia to prolonged asystole requiring resuscitation. We summarize the cases in a comparative table and propose a practical management pathway emphasizing preoperative recognition of high-risk anatomical regions, immediate interruption of surgical stimulation, graded pharmacologic treatment, and selective temporary pacing. These cases highlight that reflex-mediated cardioinhibition in selected skull base and parapharyngeal operations may be anticipated through anatomy-based perioperative reasoning.