Paradoxical bradycardia from occult venous hemorrhage mimicking vasovagal syncope - A case report -

Background: Hemorrhagic shock typically presents with tachycardia; however, profound hypovolemia can paradoxically induce bradycardia via the Bezold–Jarisch reflex. This can lead to misdiagnosis of vasovagal syncope, causing dangerous treatment delays.Case: A 50-year-old woman developed profound bradycardia and hypotension after vomiting in the post-anesthesia care unit after undergoing hysterectomy. Despite initial management of vasovagal syncope, her condition remained refractory to vasopressors. A critically low hemoglobin level of 5.5 g/dL strongly suggested massive occult hemorrhage. She underwent emergency laparotomy for a 1,500 ml pelvic hematoma and recovered without complications.Conclusions: Paradoxical bradycardia is a rare, but life-threatening, sign of occult hemorrhage. Clinicians must maintain a high index of suspicion for hemorrhage when hemodynamic instability is refractory to standard vagal management.