AGC Mode vs Minimal Flow in Breast Surgery

Comparison of AGC (Automatic Gas Control) Mode and Manually Controlled Minimal Flow Anesthesia in Breast Surgery

The aim of this study was to compare the AGC mode and manually controlled minimal-flow anesthesia for volatile anesthetic consumption, hemodynamic parameters, and recovery from anesthesia

Study Overview

• Status: Completed
• Conditions: Breast Diseases; Anesthesia; Functional; Volatil Agent Consumption; Automatic End-tidal Controlled Anesthesia
• Intervention / Treatment: Device: AGC mode

Detailed Description

Modern anesthesia machines use circular systems in which ventilated gas re-circulates to a certain degree and is therefore reused, preserving temperature, and humidity. The rebreathing fraction is increased by a reduction in fresh gas flow, which leads to a considerable decrease in consumption of fresh gas and volatile anesthetics, resulting in reductions in cost and atmospheric pollution. In a closed ventilation system, only the patient's requirements for oxygen and anesthetic agents are supplemented. A fresh gas flow-rate of 0.5 l/min is defined as the minimal-flow technique. The oxygen and anesthetic gas titration can be manually controlled by the anesthetist. To assure safe and appropriate anesthesia, manually controlled anesthesia requires constant monitoring and numerous adjustments to the gas dosage by the anesthetist, especially for low- and minimalflow anesthesia. Oxygen flow and volatile anesthetics can also be automatically controlled by anesthesia machines using end-tidal control (such as AGC mode of Maquet FLOW-i anesthesia machine), which ensures constant end-tidal concentration of oxygen and anesthetic gas via feedback and continuous automatic adjustment mechanisms. Anesthesiologists needing to make fewer interventions during a case may have clinical importance in terms of distraction, record keeping and patient safety. In addition to this advantage, we wanted to compare the AGC mode and manually controlled minimal-flow anesthesia for volatile anesthetic consumption, hemodynamic parameters, and recovery from anesthesia.

• Study Type: Observational
• Enrollment (Actual): 90

Contacts and Locations

Study Locations

• Turkey
  • Kozlu
    • Zonguldak, Kozlu, Turkey, 67600
      • Zonguldak Bülent Ecevit University Medicine Faculty

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

• Sampling Method: Probability Sample

Study Population

Between 18-65 years, female patients underwent breast surgery

Description

Inclusion Criteria:

• 18-65 years
• undergoing breast surgery
• ASA physical status I-II
• female
• operation lasting at least 1 hour
• those who agreed to volunteer for the study with an informed consent form

Exclusion Criteria:

• coronary artery disease, CHF
• pregnancy or breastfeeding women
• decompensated diabetes mellitus
• kidney or liver failure
• chronic obstructive pulmonary disease
• opioid sensitivity
• history of malignant hyperthermia
• history of smoking
• alcohol or drug addiction
• significant anemia
• sepsis
• BMI >35
• patients with allergies to the drugs used in the study

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Group AGC; The FLOW-i anesthesia machine (Maquet, Solna, Sweden) can be equipped with automated gas control (AGC), an automated low flow tool with target control of the inspired oxygen concentration (FIO2) and end-expired concentration (FA) of a potent inhaled anesthetic. İnitially before induction, we set the minimal fresh gas flow to 0.5 L min-1 and target end-expired agent concentration for 1 MAC (minimal alveolar concentration). Shortly after intubation of the patient, we switched to AGC mode.	Device: AGC mode; Automated Gas Control mode at Maquet FLOW-i anesthesia machine
Group Minimal Flow; İn this group; following intubation, we set the fresh gas flow to 4 L min-1 and than we readjusted fresh gas flow manually to 0.5 L min-1 after sevoflurane concentration reaching to 1 MAC.
Group Medium Flow; İn this group; following intubation, we set the fresh gas flow to 4 L min-1 and than we readjusted fresh gas flow manually to 2 L min-1 after sevoflurane concentration reaching to 1 MAC.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Consumption of Volatile Agent	Difference of Sevoflurane Consumption between the groups	during the surgery

Collaborators and Investigators

• Sponsor: Zonguldak Bulent Ecevit University

Study record dates

Study Major Dates

• Study Start (Actual): March 15, 2021
• Primary Completion (Actual): March 15, 2022
• Study Completion (Actual): April 4, 2022

Study Registration Dates

• First Submitted: May 30, 2022
• First Submitted That Met QC Criteria: May 30, 2022
• First Posted (Actual): June 3, 2022

Study Record Updates

• Last Update Posted (Actual): June 3, 2022
• Last Update Submitted That Met QC Criteria: May 30, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Keywords: sevoflurane; breast surgery; anesthesia machine; minimal fresh gas flow; AGC mode
• Additional Relevant MeSH Terms: Skin Diseases; Breast Diseases
• Other Study ID Numbers: 2021/05-12

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided

Drug and device information, study documents

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