title: Comparison of the Effects of Remifentanil and Dexmedetomidine Infusions on Hemodynamic Parameters and Thyroid Hormones.
abstract: OBJECTIVE
  In this study, we compared the effects of remifentanil and dexmedetomidine on hemodynamic parameters, inhalation agent consumption and thyroid hormone levels at the late postoperative period.
  
  
  METHODS
  Forty-five euthyroid ASA I-II patients between 20 and 75 years of age were randomly assigned into three groups: During induction, Group R received 1.0 mcg kg(-1) remifentanil as slow bolus in two minutes,Group D received 1.0 mcg kg(-1) dexmedetomidine in 10 minutes as infusion,Group C received 1.0 mcg kg(-1) fentanyl as bolus. Afterwards, all patients received 2.0 mg kg(-1) propofol and 0.2 mg kg(-1) cisatracurium for induction.For anaesthesia maintenance during and up to 15 minutes before the end of the surgery; Group R received 0.05 mcg kg(-1) min(-1) remifentanil,Group D received 0.5 mcg kg(-1) h(-1) dexmedetomidine infusion.During the surgery, heart rate, mean arterial pressure and end-tidal sevoflurane concentrations were recorded for every patient. Venous blood samples were taken after the operation, at postoperative 24(th) hour and postoperative 5(th) day and the variations in fT3, fT4, TSH levels were analyzed.
  
  
  RESULTS
  Mean arterial pressure values and sevoflurane consumption were lower in Group R and Group D in comparison with the control group. In comparison between groups, the decrease in fT3 values at postoperative 24(th) hour was more significant in the control group than the other two groups.
  
  
  CONCLUSIONS
  We suggest that, both agents suppress the hemodynamic response, decrease the consumption of inhalation agents and cause less change in the levels of thyroid hormones, which can be considered as one of the indicators of endocrine response.
authors.affiliation: Department of Anaesthesiology and Reanimation, Ministry Health Arnavutköy State Hospital, İstanbul, Turkey.
authors.forename: Bengü
authors.initials: B
authors.lastname: Özütürk
authors.affiliation: Department of Anaesthesiology and Reanimation, Ministry Health Okmeydanı Training and Research Hospital, İstanbul, Turkey.
authors.forename: Ayşın
authors.initials: A
authors.lastname: Ersoy
authors.affiliation: Department of Anaesthesiology and Reanimation, Faculty of Medicine, Kafkas University, Kars, Turkey.
authors.forename: Aysel
authors.initials: A
authors.lastname: Altan
authors.affiliation: Department of Anaesthesiology and Reanimation, Ministry Health Gaziantep Şehit Kamil State Hospital, Gaziantep, Turkey.
authors.forename: Levent Mehmet
authors.initials: LM
authors.lastname: Uygur
keywords: Thyroid hormones; cholecystectomy; dexmedetomidine; remifentanil; sevoflurane