Effects of Minimal and High Flow Anesthesia on Thiol Disulfide Balance and StO2 in Hypotensive Anesthesia Applications

Study Overview
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Brief Summary
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The effects of Minimal Flow Anesthesia (0.4 l / min) and High Flow Anaesthesia (2 l / min) on tissue oxygen saturation (St02) and thiol / disulfide balance in hypotensive anesthesia operations will be investigated.

Detailed Description
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The oxidative stress at the cellular level and the possible effects of general anesthesia techniques on the antioxidant system make the method of anesthesia more important. The effects of Minimal Flow Anesthesia (0.4 l / min) and High Flow Anaesthesia (2 l / min) on tissue oxygen saturation (St02) and thiol / disulfide balance in hypotensive anesthesia operations will be investigated. Minimal flow anesthesia is widely used because of its advantages such as cost reduction, prevention of environmental pollution, minimization of heat and humidity loss. Hypotensive anesthesia is preferred in some specialized surgical procedures in order to reduce bleeding and improve the surgical field of view. The use of hypotensive anesthesia and inhalation agents may cause hypoperfusion at the tissue level and cause hypoxia-induced oxidative stress and initiate cell damage. Determining the ideal anesthesia technique in terms of oxidative stress and tissue perfusion will reduce intra- and postoperative risks by protecting patients from the harmful effects of anesthesia.

Official Title
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Investigation of the Effects of Minimal and High Flow Anesthesia on Thiol Disulfide Balance and Peripheral Tissue Saturation (StO2) in Hypotensive Anesthesia Applications

Conditions
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Oxidative Stress

Intervention / Treatment
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* Other: Minimal Flow Anesthesia
* Other: High Flow Anesthesia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA (American Society of Anesthesiologists) I tympanoplasty operations with hypotensive anesthesia, ASA (American Society of Anesthesiologists) II tympanoplasty operations with hypotensive anesthesia, Exclusion Criteria: operations in less than one hour uncontrolled hypertension DM (Diabetes Mellitus) cerebrovascular disease coagulopathy morbid obesity ((BMI ≥ 35) renal disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Minimal Flow Anesthesia<br>Minimal Flow Anesthesia (50% O2, 50% air), Desflurane (MAC = 4,5). In hypotensive anesthesia application; Remifentanil will be used at infusion rates of 0.025-0.1μg / kg / min after a loading dose of 1 μg / kg / min, with mean Arterial Pressure 55-65 mmHg. Before the induction of anesthesia and 30 minutes of anesthesia, 2 ml of venous blood sample will be taken from the patients and simultaneous tissue oxygen saturation will be recorded. Serum thiol disulfide levels obtained from the blood sample of the recipient will be studied in the biochemistry research laboratory using the method developed by Erel et al. | Other: Minimal Flow Anesthesia<br>* Minimal Flow Anesthesia with 0,4 L min-1<br>|
| Other: High Flow Anesthesia<br>High Flow Anesthesia (50% O2, 50% air), Desflurane (MAC = 4,5) In hypotensive anesthesia application; Remifentanil will be used at infusion rates of 0.025-0.1μg / kg / min after a loading dose of 1 μg / kg / min, with mean Arterial Pressure 55-65 mmHg. Before the induction of anesthesia and 30 minutes of anesthesia, 2 ml of venous blood sample will be taken from the patients and simultaneous tissue oxygen saturation will be recorded. Serum thiol disulfide levels obtained from the blood sample of the recipient will be studied in the biochemistry research laboratory using the method developed by Erel et al. | Other: High Flow Anesthesia<br>* High Flow Anesthesia with 2 L min-1<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thiol Disulfide Balance | Change of Oxidative Stress Marker | For two groups; First blood sample will be taken 30 min before the start of surgery, second blood sample will be taken at the 60th min of the surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| StO2 | Change of Peripheral Tissue Oxygen Saturation | For two groups; simultaneously, 30 min before the start of surgery, 60th min of the surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Minimal Flow Anesthesia, Thiol/disulfide balance, Tissue oxygen saturation, hypotensive anesthesia