Asystole Likely Due to a Vagal Reflex During Routine Gynecologic Surgery: A Case Report

Vagal-mediated cardiovascular responses can occur following carbon dioxide pneumoperitoneum during laparoscopic surgery. In rare cases, an exaggerated vagal reflex may result in profound bradycardia or asystole. We report the case of a 44-year-old woman (American Society of Anesthesiologists physical status II) who developed abrupt bradycardia progressing to asystolic cardiac arrest immediately after abdominal insufflation during an elective minimally invasive gynecologic procedure. The planned operation included hysteroscopy with MyoSure (Hologic, Inc., Marlborough, MA, US) resection, NovaSure (Hologic) endometrial ablation, Acessa (Hologic) radiofrequency fibroid ablation, diagnostic laparoscopy, and salpingectomy for symptomatic uterine fibroids refractory to conservative management. Her past medical history was notable only for uterine fibroids and recently diagnosed hypertension. Preoperative laboratory testing and vital signs were within normal limits, and electrocardiography demonstrated normal sinus rhythm without clinically significant rhythm abnormalities. Immediately following the bradycardia, one milligram of atropine was administered intravenously. The patient then became asystolic, pneumoperitoneum was evacuated, and cardiopulmonary resuscitation was initiated. Return of spontaneous circulation was achieved after a single round of compressions, with restoration of normal sinus rhythm. The intra-abdominal portion of the procedure was subsequently aborted, and the patient remained hemodynamically stable postoperatively. At cardiology follow-up nine days postoperatively, the patient reported prior vasovagal-type episodes, including syncope following influenza vaccination and near-syncope during magnetic resonance imaging with intravenous contrast. This case highlights the importance of rapid recognition and management of vagally mediated cardiac events in the operating room. It also raises the question of whether targeted preoperative assessment for prior syncope or vasovagal episodes may help identify patients at increased risk for exaggerated vagal responses during procedures involving pneumoperitoneum, a potential area for future investigation.