Fresh Gas Flow and Lung Ultrasonography in Laparoscopic Cholecystectomy

NCT07753278 | Not Yet Recruiting

• 1 other identifier: AH-AR-MD-01
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective randomized clinical trial aims to evaluate the effects of different fresh gas flow rates on postoperative pulmonary aeration using lung ultrasonography in patients undergoing elective laparoscopic cholecystectomy. Patients will be randomly assigned to receive either low-flow anesthesia (0.5 L/min) or high-flow anesthesia (4 L/min) during maintenance of general anesthesia. The primary objective is to compare postoperative lung ultrasound scores and the incidence of atelectasis between the two groups.

Conditions

Postoperative Atelectasis; Pulmonary Atelectasis

Keywords

Fresh Gas Flow; Lung Ultrasound Score; Pulmonary Complications

Outcome Measures

Primary Outcomes (1)

• Postoperative Lung Ultrasound Score

  Lung ultrasonography will be performed 30 minutes after extubation. Both lungs will be divided into 12 regions, with 6 regions assessed in each lung. Each region will be scored from 0 to 3: 0 indicates normal aeration with A-lines or fewer than three B-lines; 1 indicates at least three well-spaced B-lines; 2 indicates coalescent B-lines; and 3 indicates lung consolidation. The scores from all regions will be summed, resulting in a total score ranging from 0 to 36. Higher scores indicate greater loss of lung aeration.

  30 minutes after extubation

Secondary Outcomes (5)

• Incidence of postoperative atelectasis

  30 minutes after extubation

• Peripheral oxygen saturation (SpO₂)

  During surgery

• Mean arterial pressure

  During surgery

• Heart rate

  During surgery

• Peak airway pressure

  Throughout the intraoperative period

Study Arms (2)

Low Fresh Gas Flow

ACTIVE COMPARATOR

Participants will receive general anesthesia with a fresh gas flow rate of 0.5 L/min during the maintenance phase following an initial fresh gas flow of 4 L/min for 8 minutes after endotracheal intubation. Postoperative lung ultrasonography will be performed 30 minutes after extubation.

Procedure: Low Fresh Gas Flow (0.5 L/min)

High Fresh Gas Flow

ACTIVE COMPARATOR

Participants will receive general anesthesia with a fresh gas flow rate of 4 L/min during the maintenance phase following an initial fresh gas flow of 4 L/min for 8 minutes after endotracheal intubation. Postoperative lung ultrasonography will be performed 30 minutes after extubation.

Procedure: High Fresh Gas Flow (4 L/min)

Interventions

Low Fresh Gas Flow (0.5 L/min) PROCEDURE

General anesthesia will be maintained using a fresh gas flow rate of 0.5 L/min after an initial fresh gas flow of 4 L/min for 8 minutes following endotracheal intubation.

Low Fresh Gas Flow

High Fresh Gas Flow (4 L/min) PROCEDURE

General anesthesia will be maintained using a fresh gas flow rate of 4 L/min after an initial fresh gas flow of 4 L/min for 8 minutes following endotracheal intubation.

High Fresh Gas Flow

Eligibility Criteria

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

You may qualify if:

• Adults aged 18 years or older.
• American Society of Anesthesiologists (ASA) physical status I-II.
• Scheduled for elective laparoscopic cholecystectomy under general anesthesia.
• Able and willing to provide written informed consent.

You may not qualify if:

• Refusal to participate in the study.
• History of chronic respiratory disease, including severe asthma, chronic obstructive pulmonary disease (COPD), or bronchiolitis.
• History of alcohol or substance abuse.
• Intraoperative airway or respiratory complications during endotracheal intubation or surgery.
• Life-threatening postoperative complications.
• Patients with ASA physical status III or higher.

Sponsors & Collaborators

• Adiyaman University: lead

Study Sites (1)

Adıyaman Training and Research Hospital

Adıyaman, 02100, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Pulmonary Atelectasis

Condition Hierarchy (Ancestors)

Lung Diseases; Respiratory Tract Diseases

Central Study Contacts

MEHMET DURAN, MD, Associate Professor

CONTACT

+90 505 689 5404; md021979@hotmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: Participants will be randomly assigned in a 1:1 ratio to either the low fresh gas flow group (0.5 L/min) or the high fresh gas flow group (4 L/min). Each participant will receive only one intervention throughout the study, and postoperative lung ultrasound findings will be compared between the two parallel groups.

Study Record Dates

• First Submitted: August 4, 2026
• First Posted: August 7, 2026
• Study Start (Estimated): August 15, 2026
• Primary Completion (Estimated): October 15, 2026
• Study Completion (Estimated): October 15, 2026
• Last Updated: August 7, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)