title: Vasovagal syncope with asystole associated with intravenous access.
abstract: Two cases of vasovagal syncope (VVS) during venous access are reported. Both patients had a history of fainting episodes and experienced bradycardia with asystole, hypotension, and fainting. Pain and phobic stress during venous access triggered an increase in parasympathetic tone, resulting in bradycardia with asystole and hypotension in both cases. Hypotension and bradycardia likely caused cerebral hypoperfusion, leading to fainting. The intense parasympathetic tone triggered by somatic or emotional stress was likely responsible for directly depressing the sinus node, leading to asystole and bradycardia. Bradycardia with asystole progressing to syncope is a potentially fatal dysrhythmia in patients with cardiovascular disease or older patients with decreased cardiac function. Appropriate treatment for VVS includes the administration of intravenous fluids, vagolytics, ephedrine, and the rapid use of the Trendelenburg position. Intravenous fluids and atropine were used to treat the present patients.
authors.affiliation: Section of Anesthesiology and Clinical Physiology, Department of Oral Restitution, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. ryoanph@tmd.ac.jp <ryoanph@tmd.ac.jp>
authors.forename: Ryo
authors.initials: R
authors.lastname: Wakita
authors.forename: Yuka
authors.initials: Y
authors.lastname: Ohno
authors.forename: Saori
authors.initials: S
authors.lastname: Yamazaki
authors.forename: Hikaru
authors.initials: H
authors.lastname: Kohase
authors.forename: Masahiro
authors.initials: M
authors.lastname: Umino
mesh_terms: D000328:Adult; D000766:Anesthesia, Dental / Q000009:adverse effects* / Q000379:methods; D001285:Atropine / Q000627:therapeutic use; D001919:Bradycardia / Q000209:etiology; D016292:Procedural Sedation / Q000009:adverse effects; D016854:Dental Anxiety / Q000150:complications; D006323:Heart Arrest / Q000209:etiology*; D006801:Humans; D008297:Male; D019647:Oral Surgical Procedures / Q000009:adverse effects*; D010276:Parasympatholytics / Q000627:therapeutic use; D018962:Phlebotomy / Q000009:adverse effects*; D019462:Syncope, Vasovagal / Q000209:etiology*
chemical_list: D010276:Parasympatholytics; D001285:Atropine