Comparison of Total Oxidant and Total Antioxidant Capacities in Low-Flow and High-Flow General Anesthesia

Comparison of Changes in Total Oxidant and Total Antioxidant Capacities in Low-Flow and High-Flow General Anesthesia Protocols

The goal of this observational study is to determine whether low-flow anesthesia has a positive contribution to the total oxidant/antioxidant balance.

Study Overview

• Status: Recruiting
• Conditions: Oxidative Stress; Anesthesia
• Intervention / Treatment: Other: general anesthesia

Detailed Description

General anesthesia is a complex physiological state characterized by reversible loss of consciousness, whole-body analgesia, amnesia, and muscle relaxation. Modern anesthesia devices used for patients under general anesthesia are semi-closed rebreathing systems. The fresh gas flow entering these closed systems is determined by the anesthetists.

The term low-flow anesthesia is used to describe inhalation anesthesia techniques that are administered with a semi-closed rebreathing system and have a rebreathing rate of at least 50%. The high standard of anesthesia machines, the existence of monitors that analyze the anesthetic gas composition continuously and in detail, and the increase in knowledge about the pharmacodynamics and pharmacokinetics of inhalation anesthetics have greatly facilitated the safe administration of low-flow anesthesia. The terminology associated with low-flow anesthesia techniques may be based on rebreathing rate or fresh gas flow rate. The most important factor determining the rebreathing rate is the fresh gas flow rate. If the fresh gas flow rate is reduced to less than 2 L/min when using modern rebreathing systems, low-flow anesthesia can be mentioned for most patients.

Oxidative stress is accepted as a pathological mechanism. Oxidative stress is a state of oxidative damage that occurs when the critical balance between free radical production and antioxidant defense systems is disrupted. Oxidative stress is beneficial in certain physiological conditions. For example, it can strengthen biological defense mechanisms during appropriate physical exercise and ischemia. However, its benefits are limited to these specific situations, and in many other cases, high levels of oxidative stress cause cell death and thus cell and tissue damage via necrotic or apoptotic mechanisms. If damage continues at the cell and tissue level, it causes the onset and progression of various organ damage and diseases.

Aim: In low-flow anesthesia applications, the amount of inspired oxygen is expected to be low due to keeping the gas supplied to the system low. Therefore, in this study, it will be investigated whether low-flow anesthesia has a positive contribution to the total oxidant/antioxidant balance.

Method: A total of 72 patients undergoing general anesthesia who meet the inclusion criteria and signed informed consent will be included in the study. Vitamin D, albumin, CRP, Total Antioxidant (TAS) and Total Oxidant (TOS) levels will be determined in the blood samples taken from all volunteers routinely before the operation. Basal peak heart rate (HR), peripheral oxygen saturation (SpO2), systolic (SBP) and diastolic blood pressure (DBP), end-tidal carbon dioxide (ETCO2), body temperature and processed EEG values will be recorded. All measurements will be recorded and repeated at 5 minute intervals throughout the operation. Volunteers will be randomly divided into 2 groups as low flow group (D) and high flow group (Y). Fresh gas flow of 1 L/min to D group and 4 L/min to Y group will be administered. During the operation, the processed EEG values of all patients will be held between 40-60 and it will be ensured that they are at the same anesthesia depth. Albumin, CRP, TAS and TOS values will be checked again in the blood samples taken for routine tests performed at the end of operation and postoperatively within 6-24 hours after the end of operation, and these values will be compared with the values obtained before the operation.

Statistical Analysis: It is planned to use 'Independent Samples t test' or 'Mann-Whitney U test' in comparison of the groups, depending on the distribution of the data. Chi-square tests will be used to examine the relationships between categorical variables. 'Repeated Measure ANOVA' will be used in the evaluation of repeated measurements. Correlations between continuous variables will be analyzed by Pearson or Spearman correlation analysis, depending on the distribution of the data.

• Study Type: Observational
• Enrollment (Estimated): 72

Contacts and Locations

• Study Contact: Name: Özlem Ersoy Karka; Phone Number: +905337293978; Email: drozlemersoy@gmail.com
• Study Contact Backup: Name: Güner Sobcalı; Phone Number: +905069016069; Email: guner_290@hotmail.com

Study Locations

• Turkey
  • Düzce
    • Duzce, Düzce, Turkey, 81000
      • Recruiting
      • Duzce University Faculty of Medicine
      • Contact: Özlem Ersoy Karka; Phone Number: +905337293978; Email: drozlemersoy@gmail.com
      • Contact: Güner Sobcalı; Phone Number: +905069016069; Email: guner_290@hotmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 58 years (Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Probability Sample

Study Population

72 patients who meet the inclusion criteria and sign informed consent will be included.

Description

Inclusion Criteria:

• Patients older than 18 years and younger than 60 years of age who will be operated under general anesthesia
• Patients in I, II risk groups according to the American Society of Anesthesiologists (ASA) classification

Exclusion Criteria:

• ASA III and above patients,
• Patients for whom Intensive Care Unit (ICU) indication is required
• Chronic obstructive pulmonary disease,
• Personal or family history of malignant hyperthermia,
• Morbid obesity,
• Alcohol or drug dependency,
• Having a history of liver or kidney disease,
• Having coronary artery disease or heart failure,
• Having significant anemia or hemoglobinopathy,
• Hypotension, hypovolemia, sepsis.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Low Flow Group - Group D; Vitamin D, Albumin, CRP, TAS and TOS values will be checked before and during the operation in 36 patients who will receive general anesthesia. Flow of 1 L/min will be given during the operation. The processed EEG values of all patients will be monitored and they will be ensured to be at the same anesthesia depth. Albumin, CRP, TAS and TOS values will be checked again from the blood taken postoperatively in the patients who were taken to the service after the operation and these values will be compared with the previous ones.	Other: general anesthesia; All patients will undergo general anesthesia. Group D will receive fresh gas flow of 1 l/min and Group Y will receive fresh gas flow of 4 l/min.
High Flow Group - Group Y; Vitamin D, Albumin, CRP, TAS and TOS values will be checked before and during the operation in 36 patients who will receive general anesthesia. Flow of 4 L/min will be given during the operation. The processed EEG values of all patients will be monitored and they will be ensured to be at the same anesthesia depth. Albumin, CRP, TAS and TOS values will be checked again from the blood taken postoperatively in the patients who were taken to the service after the operation and these values will be compared with the previous ones.	Other: general anesthesia; All patients will undergo general anesthesia. Group D will receive fresh gas flow of 1 l/min and Group Y will receive fresh gas flow of 4 l/min.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Comparison of TAS/TOS levels between the two groups	Vitamin D, Albumin, CRP, TAS and TOS values will be checked before the operation in 72 patients who will receive general anesthesia in both groups. Albumin, CRP, TAS and TOS values will be checked again from the blood taken postoperatively in the patients who were taken to the ward after the operation and these values will be compared between two groups and with the previous level in the same group.	3 times in 24 hours perioperatively. TAS/TOS levels will be determined before the operation, at the end of operation and at 6th hour after the end of operation.
Change from baseline in TAS/TOS levels	Vitamin D, Albumin, CRP, TAS and TOS values will be checked before the operation in 72 patients who will receive general anesthesia in both groups. Albumin, CRP, TAS and TOS values will be checked again from the blood taken postoperatively in the patients who were taken to the ward after the operation and these values will be compared between two groups and with the previous level in the same group.	3 times in 24 hours perioperatively. TAS/TOS levels will be determined before the operation, at the end of operation and at 6th hour after the end of operation.
Change from baseline in Albumin levels.	Vitamin D, Albumin, CRP, TAS and TOS values will be checked before the operation in 72 patients who will receive general anesthesia in both groups. Albumin, CRP, TAS and TOS values will be checked again from the blood taken postoperatively in the patients who were taken to the ward after the operation and these values will be compared between two groups and with the previous level in the same group.	3 times in 24 hours perioperatively. Albumin levels will be determined before the operation, at the end of operation and at 6th hour after the end of operation.
Change from baseline in CRP levels.	Vitamin D, Albumin, CRP, TAS and TOS values will be checked before the operation in 72 patients who will receive general anesthesia in both groups. Albumin, CRP, TAS and TOS values will be checked again from the blood taken postoperatively in the patients who were taken to the ward after the operation and these values will be compared between two groups and with the previous level in the same group.	3 times in 24 hours perioperatively. Albumin levels will be determined before the operation, at the end of operation and at 6th hour after the end of operation.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Correlation between Vitamin D level and TAS/TOS values	Vitamin D, Albumin, CRP, TAS and TOS values will be checked before the operation in 72 patients who will receive general anesthesia in both groups. Albumin, CRP, TAS and TOS values will be checked again from the blood taken postoperatively in the patients who were taken to the ward after the operation and these values will be compared between two groups and with the previous level in the same group.	1 time before the operation.

Collaborators and Investigators

• Sponsor: Duzce University
• Investigators: Principal Investigator: Özlem Ersoy Karka, Duzce University Faculty of Medicine

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2022
• Primary Completion (Estimated): August 1, 2024
• Study Completion (Estimated): August 1, 2024

Study Registration Dates

• First Submitted: October 18, 2022
• First Submitted That Met QC Criteria: October 18, 2022
• First Posted (Actual): October 21, 2022

Study Record Updates

• Last Update Posted (Actual): September 28, 2023
• Last Update Submitted That Met QC Criteria: September 27, 2023
• Last Verified: September 1, 2023

More Information

Terms related to this study

• Keywords: Oxidative stress; Anesthesia, General; Low flow anesthesia
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Central Nervous System Depressants; Anesthetics
• Other Study ID Numbers: drozlemersoy3

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No