Severe bradycardia induced by postoperative nausea and vomiting: A case report

INTRODUCTION: Postoperative nausea and vomiting is a common complication for patients after anesthesia and surgery, which may result in increased parasympathetic activity, such as diaphoresis, pallor, or bradycardia. However, few cases of fatal bradycardia induced by postoperative nausea and vomiting have been reported before. Clinicians generally attribute bradycardia to certain anesthetics, instead of postoperative nausea or vomiting. PATIENT CONCERNS: A fifty-year-old female with a history of well-controlled hypertension underwent elective radical mastectomy. When recovering from anesthesia in the post-anesthesia care unit, the patient experienced severe bradycardia accompanied by hypotension and unconsciousness, shortly after nausea and vomiting. INTERVENTIONS: The patient received cardiopulmonary resuscitation immediately. OUTCOMES: Five minutes later, She recovered sinus rhythm and her vital sings tended to be stable. Three hours later, blood tests showed the N-terminal pro-B-type natriuretic peptide 127 pg/mL and cardiac troponin I 0.44 ng/mL, which peaked to 2.65 ng/mL 10 hours after the emergency. Electrocardiography revealed sinus rhythm, ST-segment depression in the inferior and anterior lateral leads, QTc prolongation, and left ventricular high voltage. Her serum cTnI continued to decline to 0.27 ng/mL on the 3rd day after surgery. She was discharged from the hospital on the fifth day and had no sequelae. CONCLUSION: Although postoperative nausea and vomiting occurs frequently, it should be kept in mind as a potential cause to blame for severe bradycardia or even life-threatening situations.