Comparison between effectiveness of Esmolol HCL and Dexmedetomidine HCL to provide hemodynamic stability during anesthesia of middle ear surgery

Purpose: Hypotensive anesthesia is frequently implemented with different agents to reduce the amount of bleeding and to provide a better quality of surgical field vision in middle ear surgery. In our study, the efficiency of esmolol and dexmedetomidin in providing a hemodynamic stability, their effects on renal and hepatic functions were compared by aiming at a controlled hypotension between 55-70 mm Hg on patients who had tympanoplasty surgery.Material and Method: After the consent of the Ethics Committee and the written consent of the cases were taken, 40 cases from ASA I aged between 18-65, who had tympanoplasty surgery, were taken. These cases were classified into two groups randomly. 500 mcg/kg/min. esmolol was given to the first group (n=20) (Grup E) in 5 minutes before general anesthesia. 50 mcg/kg/min. maintenance infusion of esmolol during the following five minutes, and 250 mcg/kg/min. maintenance infusion of esmolol from fifth minutes to the closure of the skin were given. 1 mcg/kg. of dexmedetomidin was given to the second group (n=20) (Grup D) for every ten minutes before general anesthesia. Immediately after, 0,5 mcg/kg/h of maintenance dose was given. In both groups, induction of general anesthesia was implemented with 3-7 mg/kg thiopental, 0,1 mg/kg vecuroniom, 2 % sevofluran, 35 % O2 and 65 % N2O. 10- 15 minutes before the surgeon apply graft, N2O was ceased and 100 % O2 application started in both groups. Preoperative, peroperative and postoperative data (MAP, HR), six degree bleeding scale to evaluate the cleanliness of surgical field, preoperative, postoperative BUN, Creatinine, ALT, AST to evaluate renal and hepatic functions, sevofluran consumption, and again preoperative- postoperative PaO2, SpO2 parameters were recorded in all cases.Results: The demographic features of groups, preoperative and intraoperative hemodynamic parameters were similar. Postoperative heart rate was relatively low in Group D. Preoperative and postoperative BUN, Creatinine, ALT, AST parameters were similar, but postoperative BUN and Creatinine parameters in Group E progressed in a lower way compared with preoperative period provided that staying within normal limits. When it?s evaluated according to the six degree scale (p<0,05), bleeding scores were relatively lower in Group E. Therefore, quality of surgical vision was better. (p<0,05) With that Sevofluran consumption decreased noticeably in intraoperative period in both groups (p<0,001), Sevofluran consumption was relatively lower in Group E. (p<0,05)Conclusion: It was concluded that an ideal hemodynamic stability was provided with esmolol and dexmedetomidin in application of controlled hypotension in middle ear surgery, there was no change in renal and hepatic functions with both of them, the quality of surgical field vision was provided more effectively with esmolol and there was less sevofluran consumption in group of esmolol.Key Words: Middle ear surgery, Esmolol, Dexmedetomidin, Hypotensive Anesthesia, Controlled Hypotension, Renal and hepatic functions, Sevofluran