Oxidative stress at the cellular level and the effects of the antioxidant system on the anesthetic drugs make the anesthesia method more important. Hypotensive anesthesia or controlled hypotension is an anesthetic technique routinely used in many operations (ENT, orthopedic, plastic surgery, etc.) to reduce intraoperative bleeding and to provide a more open surgical area.

In this study, investigators aimed to investigate the effects of hypotensive anesthesia on thiol / disulfide balance from oxidative stress markers.

Hypotensive anesthesia is caused by hypoperfusion and hypoxia-induced oxidative stresses at the tissue level and can initiate cell damage. Many methods can be used alone or in combination to create hypotensive anesthesia. İnvestigators will investigate whether hypotensive anesthesia causes an effect on the cellular level.

This study will be performed prospectively with 80 participants with ASA 1-2, aged 18-60 years, undergoing hypotensive anesthesia in the operation of the septoplasty in Recep Tayyip Erdoğan University Medical Faculty Training and Research Hospital. Participants with uncontrolled hypertension, diabetes mellitus, cerebrovascular disease, cogulopathy, morbid obesity (BMI ≥35) and renal disease will not be taken. Anesthesia induction and management will be standardized. Hypotension in the participants will be maintained by reducing the mean arterial pressure (MAP) by 30% or 55-65 mmHg according to the initial value. In the study, the heart rate (HR), MAP, peripheral O2 saturation (SpO2), ETCO2 (end-tidal carbon dioxide) values, and BIS (Bispectral index) values showing anesthesia depth are to be followed. Participants will receive venous blood sample of up to 2 ml before the anesthesia induction and 10 minutes to finish of the hypotensive anesthesia, from the untreated vein. Thiol disulfide levels from this blood sample will be studied in the biochemistry research laboratory using the method developed by Erel et al.

Inclusion Criteria:

(American Society of Anesthesiologists) ASA Classification I - II controlled hypotensive anesthesia applied septoplasty operations

Exclusion Criteria:

Patients with uncontrolled hypertension, Diabetes Mellitus cerebrovascular disease, coagulopathy, morbid obesity ((BMI ≥35) and those with renal disease will not be taken

patients that are controlled hypotensive anesthesia applied septoplasty operations