Low-Flow Anesthesia and Open-Heart Surgery

NCT07040735 | Recruiting

• 1 other identifier: 2025-146
• Study Type: observational
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

Low-flow anesthesia (LFA) is a technique in which at least 50% of the exhaled air, after carbon dioxide absorption, is mixed with a certain amount of fresh gas and returned to the patient during the next inspiration. In 1974, R. Virtue defined minimal flow anesthesia (MFA) as 0.5 L/min. In 1984, Baker and Simionescu classified LFA as 0.5-1 L/min and MFA as 0.25-0.5 L/min. The aim of this study is to investigate whether there are hemodynamic differences between open-heart surgery cases performed with LFA at different fresh gas flow rates.

Conditions

Low-flow Anesthesia; Hemodynamics; Open-heart Surgery

Keywords

Low-flow anesthesia; Hemodynamics; Open-heart surgery

Outcome Measures

Primary Outcomes (5)

• physiological parameter ; heart rate

  Heart rate will be recorded every 10 minutes, expressed as beats per minute, starting before induction and including the sternotomy and pericardiotomy periods.

  Intraoperatively

• physiological parameter; systolic/diastolic blood pressure

  Systolic and diastolic blood pressure will be recorded every 10 minutes in mmHg, starting before induction and including the sternotomy and pericardiotomy periods.

  Intraoperatively

• physiological parameter; SpO2

  SpO2 will be recorded as a percentage every 10 minutes, starting before induction and including the sternotomy and pericardiotomy periods.

  Intraoperatively

• Monitoring parameter; Bispectral Index (BIS)

  The BIS value will be recorded numerically every 10 minutes, starting from before induction and including the sternotomy and pericardiotomy periods.

  Intraoperatively

• Monitoring parameter; Minimum alveolar concentration (MAC)

  The MAC value will be recorded numerically every 10 minutes, starting from before induction and including the sternotomy and pericardiotomy periods.

  Intraoperatively

Secondary Outcomes (3)

• Preoperative data; ASA (American Society of Anesthesiologists) classification

  24 hours before surgery

• Preoperative data

  24 hours before surgery

• Preoperaitive data

  24 hours before surgery

Study Arms (4)

Group 1

Followed using Bispectral Index (BIS) with 4% Sevoflurane and fresh gas flow set at 0.5 L/min

Group 2

Followed using Minimum Alveolar Concentration (MAC) with 4% Sevoflurane and fresh gas flow set at 0.5 L/min

Group 3

Followed using BIS with 4% Sevoflurane and fresh gas flow set at 1 L/min

Group 4

Followed using MAC with 4% Sevoflurane and fresh gas flow set at 1 L/min

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

≥18 years and scheduled for open-heart surgery patients

You may qualify if:

• ≥18 years and scheduled for open-heart surgery patients
• ASA I-II-III-IV physical class

You may not qualify if:

• Emergency cases
• Patients under 18 years of age
• Patients who have had open heart surgery before
• Patients for whom the use of inhaled anesthetic agents is contraindicated
• Patients who do not sign a voluntary consent form

Sponsors & Collaborators

• Çağrı Özdemir: lead

Study Sites (1)

Gazi University Faculty of Medicine

Ankara, Turkey (Türkiye)

RECRUITING

Central Study Contacts

Çağrı Özdemir

CONTACT

+905544239196; cagriozdemir@gazi.edu.tr

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: asst. prof.

Study Record Dates

• First Submitted: June 6, 2025
• First Posted: June 27, 2025
• Study Start: July 1, 2025
• Primary Completion (Estimated): September 2, 2026
• Study Completion (Estimated): September 23, 2026
• Last Updated: May 27, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)