The goal of this study is to find out whether listening to music during surgery can reduce the amount of propofol, an anesthesia medicine, needed in patients having elective breast surgery.

Patients who agree to take part will be randomly assigned to one of two groups. One group will listen to music of their choice through headphones during anesthesia and recovery. The other group will receive standard anesthesia care without music. All patients will receive routine anesthesia monitoring, including a monitor that helps assess the depth of anesthesia.

The main outcome of the study is the total amount of propofol used during surgery. The study will also look at anesthesia depth values, use of other anesthesia medicine, blood pressure and heart rate, time spent in the recovery unit, nausea and vomiting after surgery, and patient satisfaction.

This is a single-center, prospective, randomized, controlled, two-arm study conducted at Bursa Uludag University Faculty of Medicine, Department of Anesthesiology and Reanimation. The study population will include adult patients scheduled for elective breast surgery under total intravenous anesthesia.

After providing written informed consent, eligible participants will be randomized into two groups. The control group will receive routine anesthesia care in a standard operating room environment. The music group will receive the same anesthesia protocol and will listen to self-selected music using noise-cancelling Bluetooth headphones from immediately before anesthesia induction until discharge from the post-anesthesia care unit.

All patients will undergo standard intraoperative monitoring, including electrocardiography, noninvasive blood pressure, pulse oximetry, capnography, and bispectral index monitoring. Anesthesia will be induced and maintained according to a standardized total intravenous anesthesia protocol using propofol and remifentanil. Propofol administration will be titrated to maintain the BIS value within the target range of 40-60.

The primary outcome is total propofol consumption expressed as mg/kg. Secondary outcomes include intraoperative BIS values recorded at regular intervals, remifentanil consumption, heart rate and blood pressure measurements, post-anesthesia care unit length of stay, postoperative nausea and vomiting, and patient satisfaction before discharge from the post-anesthesia care unit.

Inclusion Criteria:

• Age between 18 and 70 years
• American Society of Anesthesiologists physical status I or II
• Scheduled to undergo elective breast surgery with an estimated surgical duration of 45 to 180 minutes
• Planned anesthesia technique is total intravenous anesthesia
• Able to understand Turkish and communicate verbally
• Able to read and write and provide written informed consent
• Clinically normal hearing function and no ear, nose, or throat condition that prevents headphone use

Exclusion Criteria:

• Diagnosed unilateral or bilateral hearing loss or use of a hearing aid
• Current psychiatric disease or regular use of psychotropic medication, including antidepressants, antipsychotics, anxiolytics, or hypnotics
• Diagnosis of chronic pain syndrome or chronic use of opioids, pregabalin, or gabapentin
• Neurological disease that may affect BIS interpretation, such as epilepsy, dementia, stroke sequelae, or Parkinson disease
• Known allergy or contraindication to propofol, remifentanil, or rocuronium
• Morbid obesity, defined as body mass index greater than 40 kg/m²
• History of active alcohol or substance dependence
• Pregnancy or breastfeeding
• Emergency surgery or reoperation
• Planned addition of regional anesthesia in the preoperative period
• Refusal to participate in the study or refusal to sign the informed consent form

Individual participant data will not be shared because the study data contain clinical perioperative information and will be handled in accordance with institutional data protection requirements and Turkish personal data protection regulations. De-identified aggregate results may be reported in scientific publications.

The anesthesia team will not be blinded to group allocation. The surgeon, post-anesthesia care unit staff, and outcome assessor will not be informed of the assigned group.