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Introduction: Clonidine, as a premedicant in anesthesia, has a special role in decreasing anesthetic agents' dose and improving sedation. Because of its effects on body hemodynamics and electrolytes and the importance of these effects during anesthesia, we decided to investigate these side effects in this study. Materials and Methods: This is a double blind randomized clinical trial. Samples were 104 ASA Class Ι & Π, 20-40 years old patients, undergoing elective surgery and were divided equally into two groups (case and control). 90 minutes before induction of anesthesia, 5μg/kg Clonidine was given to the case and placebo to the control group orally. Blood samples were taken before and 4 hours after induction of anesthesia. Also 24 hours urine was collected and measured for volume and sodium and potassium concentrations. Data analysis was done using independent T test. Results: There wasn’t any significant difference between two groups in the mean concentration of blood sodium and potassium before and after taking the drug. But the mean sodium and potassium concentration in urine was significantly more in the case group (P = 0.022 and P = 0.003 respectively). The volume of 24 hours urine was also more in the case group (P = 0.008). Conclusion: Although Clonidine induces diuresis and increases sodium and potassium excretion, blood concentration of these electrolytes doesn’t change significantly.

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Background: Due to high prevalence of vitrectomy surgery, and the importance of anesthetic technique in conducting an uncomplicated surgery, we decided to do this study.

Materials and Methods: This prospective randomized study was conducted on 80 patients 40-80 years old candidating deep vitrectomy sugery under general anesthesia that were categorized into II and III Class by American Society of Anesthesiologist (ASA). Patients were randomly allocated to two groups of 40 members. Anesthesia was induced in both groups in the same manner. For maintaining anesthesia, patients from I group receiVed 1.2% isofluran with 50% O2 in air at 4L/min and infusion of remifentanil (0.1 mg.kg-1.min-1). But in the P group, we used propofol up to 10mg/kg /hr with infusion of remifentanyl. Propofol and isoflurane in fusion was discontinued with the last surgical stitches, but remifentanil infusion continued in both groups until the eye was covered with shield. Hemodynamic variables were recorded just before the induction of anesthesia and in different time intervals till discharging of the patients from the recovery room.  Then, data were compared.

Results: Results showed that there is a significant changes in propofol group compared to isofluran in deep vitrectomy surgery operations.

Conclusion: Hemodynamic changes are more significant in maintaining propofol anesthesia when compared with isoflurane.