Transient Loss of Consciousness during Transportation after Intravenous Sedation with Dexmedetomidine

Abstract

  We herein report a patient who experienced a transient loss of consciousness while being transported to a ward by wheelchair after undergoing intravenous sedation with dexmedetomidine for tooth extractions.

  The patient was a 38-year-old woman with a height of 159 cm and a weight of 53 kg. She did not have any significant medical history. The patient underwent the extraction of two molars under intravenous sedation with dexmedetomidine. In accordance with the standard method, 4 μg/kg/h of dexmedetomidine was intravenously administered for 10 min, followed by the continuous administration of dexmedetomidine at 0.3 μg/kg/h until 10 min before the end of the surgery. After the operation, the patient was followed-up in the dental chair for 20 min (10 min in a supine position and 10 min in a sitting position). The patient’s vital signs were stable during this period. A sudden loss of consciousness subsequently occurred after the patient complained of nausea and light-headedness during transport to a ward by wheelchair.

  The loss of consciousness in the patient was probably a case of non-cardiac syncope, since she recovered consciousness after 1 min without the use of medication, she did not exhibit any neuropsychiatric symptoms, and her cardiac function was normal. The syncope episode might have been caused by the combined action of an increased circulatory burden from maintaining a sitting position and the inhibition of sympathetic nerve activity after the administration of dexmedetomidine.