title: Autonomic nervous function in upper gastrointestinal endoscopy: a prospective randomized comparison between transnasal and oral procedures.
abstract: BACKGROUND
  Transnasal esophagogastroduodenoscopy (EGD) using an ultrathin endoscope is less stressful to the cardiovascular system with less elevation of systolic blood pressure (BP) than oral procedures. To elucidate the mechanism of such beneficial cardiovascular responses, we performed a prospective patient-centered randomized study in which BP and pulse rate (P), as well as autonomic nervous functions, were estimated during transnasal EGD compared with those in oral procedures using the same ultrathin endoscope.
  
  
  METHODS
  The study involved 781 patients, among whom 55 and 56 cases were assigned to transnasal and oral EGD groups, respectively. The autonomic nervous responses were determined employing power spectral analysis (PSA) of heart-rate variations on electrocardiogram. PSA data were based on two peaks in low frequency (LF) and high-frequency (HF) ranges. HF power and the ratio of LF power/HF power represented parasympathetic and sympathetic nervous activities, respectively.
  
  
  RESULTS
  Our study confirmed the lesser elevation of BP and P in patients undergoing transnasal EGD than in those undergoing oral procedures. PSA revealed a lower increase in LH power/HF power in transnasal EGD than in oral EGD. However, both endoscopic procedures equally suppressed HF power. Significant correlations were found between the parameters of cardiovascular response (P and BP) and autonomic functions (LF power/HF power ratio and HF power).
  
  
  CONCLUSIONS
  This is the first study demonstrating less sympathetic stimulation in patients undergoing transnasal EGD, leading to lesser elevation of BP and P.
authors.affiliation: Department of Gastroenterology, Inuyama Chuo Hospital, Goromuru, Inuyama, Aichi, 484-8511, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Mori
authors.forename: Noritsugu
authors.initials: N
authors.lastname: Ohashi
authors.forename: Hideharu
authors.initials: H
authors.lastname: Tatebe
authors.forename: Takako
authors.initials: T
authors.lastname: Maruyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Inoue
authors.forename: Shoudou
authors.initials: S
authors.lastname: Takegoshi
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Kato
authors.forename: Masataka
authors.initials: M
authors.lastname: Okuno
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001341:Autonomic Nervous System / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D004562:Electrocardiography; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005767:Gastrointestinal Diseases / Q000175:diagnosis* / Q000503:physiopathology; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009055:Mouth; D009666:Nose; D010045:Outpatients; D011446:Prospective Studies