Personalized Music and Dreaming During Propofol Sedation

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.