title: The effects of reactive hyperemia on stimulation of endothelium-derived nitric oxide in on-pump and off-pump coronary artery bypass surgeries.
abstract: The purpose of this study is to compare the effects of cardiopulmonary bypass (CPB) on the endothelium-derived nitric oxide (NO) levels in on-pump and off-pump coronary artery bypass surgeries. Forty consecutive patients were divided randomly into two groups depending on use of CPB in coronary artery bypass graft surgery (group 1: n = 20, off-pump, and group 2: n = 20, on-pump). The plasma endothelium-derived NO levels were determined at baseline and after reactive hyperemia before and after surgery. Reactive hyperemia was induced by inflating a blood pressure cuff placed on the upper forearm, for 5 min at 250 mm Hg followed by a rapid deflation. Blood was collected at 1 min after cuff deflation from the radial artery on the same side. Preoperative use of all medications was recorded. The baseline plasma NO levels before operation were 17.10 ± 7.58 in group 1 and 15.49 ± 5.26 nmol/L in group 2. Before operation after reactive hyperemia, the plasma NO levels were 26.97 ± 11.49 in group 1 and 26.57 ± 12.87 nmol/L in group 2. Two hours after surgery, the plasma NO levels at baseline and after reactive hyperemia were not significantly different from each other (group 1: 18.03 ± 6.37 and group 2: 19.89 ± 9.83 nmol/L; group 1: 27.89 ± 18.36 and group 2: 39.13 ± 23.60 nmol/L, respectively; P > 0.05). A positive correlation was shown between preoperative nitroglycerine use and the postoperative plasma NO levels after reactive hyperemia (r = 0.51, P = 0.001). Linear regression analysis was performed (F = 4.10, R = 0.56, R(2)  = 0.32, P =  0.008) and the only independent parameter that had an effect on postoperative plasma NO levels after reactive hyperemia was found to be preoperative nitroglycerine use (t = 3.68, P = 0.001). Coronary artery bypass surgery with CPB does not have significant effect on plasma endothelial derived NO levels. The postoperative plasma NO levels after reactive hyperemia significantly correlated with preoperative nitroglycerine use.
authors.affiliation: Department of Cardiac Surgery, Kartal Kosuyolu Heart and Research Center, Istanbul, Turkey. sasmazel@yahoo.com
authors.forename: Ahmet
authors.initials: A
authors.lastname: Sasmazel
authors.forename: Atakan
authors.initials: A
authors.lastname: Erkılıç
authors.forename: Fuat
authors.initials: F
authors.lastname: Buyukbayrak
authors.forename: Ayse
authors.initials: A
authors.lastname: Baysal
authors.forename: Kursat
authors.initials: K
authors.lastname: Tigen
authors.forename: Altug
authors.initials: A
authors.lastname: Tuncer
authors.forename: Eylem
authors.initials: E
authors.lastname: Tuncer
authors.forename: Onursal
authors.initials: O
authors.lastname: Bugra
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ozkokeli
authors.forename: Taner
authors.initials: T
authors.lastname: Kucukcerit
authors.forename: Hasan
authors.initials: H
authors.lastname: Sunar
authors.forename: Rahmi
authors.initials: R
authors.lastname: Zeybek
mesh_terms: D000368:Aged; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D047549:Coronary Artery Bypass, Off-Pump; D003324:Coronary Artery Disease / Q000601:surgery*; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000097:blood*
chemical_list: D009569:Nitric Oxide