This study investigates how different breathing machine (ventilator) settings affect the energy delivered to the lungs during surgery. Mechanical power is a measure of this energy, and high levels can sometimes lead to lung irritation. In clinical practice, a mode called Pressure-Regulated Volume Control (PRVC) is often used because it lowers the "peak" pressure in the airways, which is generally thought to be safer. However, doctors have noticed that even though the peak pressure goes down in PRVC mode, the total mechanical power displayed on the monitor might actually increase compared to the standard Volume-Controlled Ventilation (VCV) mode. In this study, patients undergoing gallbladder surgery will be monitored using both ventilation modes in a random order. The researchers will compare the machine-calculated mechanical power for both modes to see if the perceived benefit of lower peak pressure in PRVC actually results in lower overall energy transfer to the lungs.

Inclusion Criteria:

• Patients undergoing elective laparoscopic cholecystectomy surgery.
• Patients between 18 and 75 years of age.
• American Society of Anesthesiologists (ASA) physical status I, II or III.
• Body Mass Index (BMI) between 18.5 and 35 kg/m².
• Voluntary written informed consent for participation.

Exclusion Criteria:

• History of significant chronic obstructive pulmonary disease (COPD) or asthma.
• Previous lung resection or major thoracic surgery.
• Heavy smokers (more than 20 cigarettes per day).
• Presence of spontaneous breathing effort during mechanical ventilation.
• Conversion from laparoscopic surgery to open surgery during the procedure.
• Emergency surgery cases.
• Known pregnancy.

The de-identified individual participant data (including study protocol and statistical analysis plan) will be made available upon reasonable request to the corresponding author, following the publication of the study results.

The data will be coded and analyzed by a researcher blinded to the ventilation mode sequences