title: Dexmedetomidine sedation during the nighttime reduced the incidence of postoperative atrial fibrillation in cardiovascular surgery patients after tracheal extubation.
abstract: BACKGROUND
  Dexmedetomidine (Dex) provides sedation and analgesia by acting on central alpha-2 receptors and is suitable for use after extubation because it has little respiratory depression. Considering the sympathoinhibitory and anxiolytic action of Dex, there is the possibility that Dex might reduce the incidence of atrial fibrillation (AF), which is recognized as a common complication after cardiovascular surgery. We investigated whether the postoperative incidence of AF decreased in patients who received Dex only during the nighttime in the intensive care unit (ICU).
  
  
  METHODS
  We retrospectively reviewed ICU charts to determine the incidence of AF and associated factors during the 2-day period after tracheal extubation in patients who underwent cardiovascular surgery from November 2009 to November 2010. The patients were divided into a Dex group (n = 16) and a non-Dex group (n = 29).
  
  
  RESULTS
  There were no differences in AF risk factors except for diabetes between the two groups. The average rate of Dex administration was 0.3 ± 0.2 μg/kg/h. There were also no differences between the groups in heart rate during the daytime, central venous pressure, body temperature, white blood cell count, serum level of C-reactive protein, catecholamine use, beta-blocker use, and amount of fentanyl. AF developed in one patient in the Dex group (6.3 %) and ten patients in the non-Dex group (34.5 %) during the observation period, and the difference was significant (p = 0.035). None of the risk factors for AF was significantly associated with AF in univariate analysis; however, multivariate logistic regression analysis using age, Dex use, and beta-blocker use, extracted because their p values in univariate analysis were not exceeding 0.15, showed that Dex use was the only factor associated with the development of AF (p = 0.045, odds ratio 9.75 [1.05-90.8]).
  
  
  CONCLUSIONS
  The results suggest that adequate sedation with Dex during the nighttime can reduce the incidence of AF in cardiovascular surgery patients after extubation.
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Ayuka
authors.initials: A
authors.lastname: Narisawa
authors.affiliation: Department of Intensive Care, Yamagata University Hospital, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Nakane
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Kano
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Momose
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Onodera
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Akimoto
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Tadahiro
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Iwabuchi
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Okada
authors.affiliation: Department of Dental Anesthesiology, Health Sciences University of Hokkaido, 1757 tobetsu-cho kanazawa, Ishikari-gun, Hokkaido 061-0293 Japan.
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Miura
authors.affiliation: Department of Anesthesiology, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata City, Yamagata 990-9585 Japan.
authors.forename: Kaneyuki
authors.initials: K
authors.lastname: Kawamae
keywords: After tracheal extubation; Atrial fibrillation; Cardiovascular surgery; Dexmedetomidine; Intensive care unit