Effect of Intraoperative Salbutamol Administration on Mechanical Power and Respiratory Mechanics in Obese Patients Undergoing Laparoscopic Bariatric Surgery (Bariatric)

January 22, 2026 updated by: Hülya Tosun Söner, Saglik Bilimleri Universitesi Gazi Yasargil Training and Research Hospital

The primary objective of this study is to evaluate the effect of intraoperative salbutamol administration on mechanical power in obese patients undergoing laparoscopic bariatric surgery under general anesthesia. Mechanical power will be measured at predefined intraoperative time points (T0, T1, and T2), and changes over time will be compared to determine the impact of salbutamol on the overall energy delivered to the respiratory system during mechanical ventilation.

Secondary objectives include the assessment of intraoperative respiratory mechanics, including peak airway pressure (Ppeak), plateau pressure (Pplat), driving pressure (Pdrive), airway resistance (Raw), and lung compliance, as well as gas exchange parameters (SpO₂, EtCO₂) and hemodynamic variables (mean arterial pressure). Postoperative pulmonary outcomes will be evaluated using the Melbourne Group Scale (MGS), with a score greater than 4 indicating the presence of postoperative pulmonary complications. The study aims to investigate whether improvement in intraoperative mechanical power and respiratory mechanics is associated with a reduction in postoperative pulmonary complications in this high-risk population.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

66

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Turkey (Türkiye)
    • Diyarbakır
      • Kayapınar, Diyarbakır, Turkey (Türkiye)
        • Health Sciences University Gazi Yaşargil Training and Research Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Age: 18-65 years

BMI ≥35 kg/m² (candidates for obesity surgery)

Scheduled for elective laparoscopic bariatric surgery

ASA physical status I-III

Signed informed consent

Exclusion Criteria:

Known allergy or contraindication to salbutamol

Severe cardiovascular disease (e.g., recent MI, uncontrolled arrhythmia)

Pre-existing severe pulmonary disease (e.g., severe COPD, asthma exacerbation)

Pregnancy or lactation

Emergency surgery

Use of β-agonists or bronchodilators within 24 hours prior to surgery

Patients with inability to provide informed consent

-

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Salbutamol Group
Participants in this arm will receive intraoperative salbutamol administration in addition to standard general anesthesia and mechanical ventilation during laparoscopic bariatric surgery.
Drug: Salbutamol (Ventolin®)
Salbutamol will be administered intraoperatively via the respiratory circuit during mechanical ventilation to assess its effect on mechanical power and respiratory mechanics.
Placebo Comparator: Control Group
Participants in this arm will receive intraoperative administration of normal saline (0.9% sodium chloride) via the respiratory circuit, in addition to standard general anesthesia and mechanical ventilation during laparoscopic bariatric surgery.
Drug: Normal Saline (0.9% Sodium Chloride)
Normal saline will be administered intraoperatively via the respiratory circuit in the same volume and manner as salbutamol to serve as a placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in intraoperative mechanical power
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Mechanical power will be measured directly by the ventilator/respiratory monitoring device using ventilator parameters (tidal volume, respiratory rate, peak and plateau pressures, driving pressure, and compliance) at T0, T1, and T2. The primary outcome is the difference in mechanical power between the Salbutamol and placebo groups over time.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Peak airway pressure (Ppeak)
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Peak airway pressure will be measured directly by the ventilator/respiratory monitoring device at T0, T1, and T2 to assess intraoperative respiratory mechanics.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Plateau pressure (Pplat)
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Plateau pressure will be measured by the ventilator device at T0, T1, and T2 to evaluate changes in lung mechanics.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Driving pressure (Pdrive)
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Driving pressure (Pplat minus PEEP) will be measured via the ventilator device at all intraoperative time points to assess lung stress.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Airway resistance (Raw)
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Airway resistance will be recorded from the ventilator/monitoring device at each time point to evaluate intraoperative airway changes.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Lung compliance
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Lung compliance will be measured by the ventilator at T0, T1, and T2 to assess changes in respiratory mechanics.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Lung elastance (E)
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Lung elastance will be measured directly by the ventilator/monitoring device at each intraoperative time point (T0, T1, T2) to evaluate the stiffness of the respiratory system and its changes due to pneumoperitoneum and Ventolin/SF administration.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Heart rate (HR / Nabız)
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Heart rate will be monitored continuously and recorded at T0, T1, and T2 to evaluate intraoperative hemodynamic stability and potential effects of pneumoperitoneum and Ventolin/SF administration.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Mean arterial pressure (MAP)
Time Frame: Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Mean arterial pressure will be monitored continuously and recorded at T0, T1, and T2 to assess intraoperative hemodynamic stability and the effects of pneumoperitoneum and Ventolin/SF administration.
Baseline (intraoperative, after establishment of pneumoperitoneum and before Ventolin or saline administration)
Postoperative pulmonary complications (Melbourne Group Scale >4)
Time Frame: First assessment: Within 24 hours postoperatively Second assessment: 48 hours postoperatively Third assessment: Immediately before hospital discharge

Incidence of postoperative pulmonary complications will be assessed using the Melbourne Group Scale (MGS). A score greater than 4 indicates the presence of a postoperative pulmonary complication. Criteria include:

Temperature >38°C

White cell count >11.2 ×10⁹/L or use of respiratory antibiotics

Physician diagnosis of pneumonia or chest infection

Chest X-ray findings of atelectasis or consolidation

Production of purulent (yellow/green) sputum different from preoperative sputum

Positive microbiological analysis of sputum

SpO₂ <90% in ambient air

Re-admission to or prolonged stay (>36 h) in ICU/high dependency unit for respiratory problems

Patients meeting ≥4 of these criteria at any assessment point will be recorded as having a postoperative pulmonary complication.
First assessment: Within 24 hours postoperatively Second assessment: 48 hours postoperatively Third assessment: Immediately before hospital discharge

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Saglik Bilimleri Universitesi Gazi Yasargil Training and Research Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

January 1, 2026

Primary Completion (Estimated)

March 1, 2026

Study Completion (Estimated)

March 15, 2026

Study Registration Dates

First Submitted

December 26, 2025

First Submitted That Met QC Criteria

January 22, 2026

First Posted (Actual)

January 30, 2026

Study Record Updates

Last Update Posted (Actual)

January 30, 2026

Last Update Submitted That Met QC Criteria

January 22, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • Hts

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Bariatric Surgery

Clinical Trials on Salbutamol (Ventolin®)

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Hong Kong

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe