Many patients report dreams during intravenous (IV) propofol sedation, but it is uncertain whether listening to music changes how often dreams occur or how pleasant they feel. This single-center randomized study compared three auditory conditions during propofol sedation for elective surgery under spinal anesthesia or peripheral nerve block: (1) patient-selected preferred music, (2) matched non-preferred music, and (3) silence (headphones only). Music or silence was delivered through identical closed-back headphones starting 1-2 minutes before sedation and continuing until the end of sedation.

The main outcomes were (1) whether a dream occurred (yes/no) assessed by a neutral modified Brice interview in the post-anesthesia care unit (PACU), and (2) dream pleasantness rated on a 0-10 scale among participants who reported a dream. Additional outcomes included coded dream content features, patient satisfaction, sedative dose, hemodynamic variability, early recovery measures, postoperative symptoms, and adverse events.

This is a single-center, parallel-group, three-arm randomized controlled trial evaluating the effects of auditory stimulation and music personalization on dreaming during IV propofol sedation. Adults (≥19 years) undergoing elective procedures under spinal anesthesia or peripheral nerve block with propofol sedation were eligible (ASA I-III). Participants were excluded for planned general anesthesia, severe hearing impairment, major psychiatric instability, expected significant bleeding, inability to complete interviews, or contraindication to sedative agents.

Randomization and blinding: Participants were randomized 1:1:1 to Preferred Music, Matched Non-preferred Music, or Silence using computerized randomization with variable block sizes, stratified by procedure category and preoperative anxiety (STAI-State tertiles). Allocation was concealed. An audio technician (non-assessor) set up the assigned condition. PACU interviewers, dream-content coders, and statisticians were blinded. Standardized closed-back headphones were used for all groups, with scripted staff interactions and calibrated volume (50-60 dB(A)) to support blinding; blinding integrity was assessed by questionnaire.

Interventions:

• Preferred Music: Participants selected one personally meaningful track preoperatively. The track was played continuously on loop through closed-back headphones starting 1-2 minutes before sedative infusion and continued until the end of sedation.

Final-The effect of Auditory St…

• Matched Non-preferred Music: Participants listened to a pleasant non-selected track matched to the preferred selection for tempo (±10 bpm), genre family, and loudness to separate preference effects from acoustic features; playback timing was identical.
• Silence Control: Participants wore identical headphones for the same duration without audio playback.

Sedation protocol and monitoring: Propofol was administered per a standardized regimen (initial bolus 0.5-1 mg/kg followed by infusion 25-75 µg/kg/min) titrated to maintain BIS 65-85. Sedation depth was assessed using MOAA/S (primary) and RASS (secondary), with routine physiologic monitoring and supplemental oxygen.

Outcomes: Co-primary outcomes were (1) dream incidence (yes/no) assessed by a neutral modified Brice interview in PACU, with the primary contrast of Music-pooled (Preferred or Non-preferred) versus Silence; and (2) dream pleasantness (0-10 numeric scale) among recallers, with the primary contrast of Preferred versus Matched Non-preferred music. PACU interview timing used prespecified readiness criteria and was initiated at approximately 15 minutes (±5) after PACU arrival, repeated every 5-10 minutes if needed up to 60 minutes. Secondary outcomes included blinded coded dream content features, patient satisfaction, sedative dose, hemodynamic variability, recovery endpoints (e.g., Aldrete-based recovery and PACU length of stay), postoperative symptoms (pain, nausea/vomiting, shivering), and adverse events.

Inclusion Criteria:

• Adults aged ≥ [19] years and ≤ [70] years.
• Scheduled for an elective procedure under intravenous propofol sedation at Wonkwang University Hospital.
• American Society of Anesthesiologists (ASA) physical status I-III.
• Able to understand the study procedures and provide written informed consent.

Exclusion Criteria:

• Known hearing impairment that would interfere with headphone-based auditory intervention.
• Pre-existing cognitive impairment or delirium at baseline (e.g., diagnosed dementia or active delirium).
• Use of sedatives, hypnotics, or psychoactive medications that could confound dreaming assessment, per protocol.
• Significant neurologic or psychiatric disorder that may affect dream recall/reporting.
• Inability to complete the postoperative PACU interview or inability to communicate reliably.
• Any condition judged by the investigator to make participation unsafe or data uninterpretable.

Allocation was concealed and managed by a non-assessor audio technician. Standardized closed-back headphones were used in all arms (silence arm without playback). PACU interviewers, content coders, and statisticians were blinded to group assignment; scripted interactions and volume calibration supported blinding.