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.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
SUPPORTIVE_CARE
Masking
TRIPLE
Enrollment
300
Standardized closed-back headphones are used to deliver music during IV propofol sedation. Depending on randomization, participants receive self-selected preferred music. Playback begins shortly before sedation and continues until the end of sedation; volume is calibrated per protocol.
Standardized closed-back headphones are used to deliver music during IV propofol sedation. Depending on randomization, participants receive e matched non-preferred music. Playback begins shortly before sedation and continues until the end of sedation; volume is calibrated per protocol.
Participants wear identical closed-back headphones during IV propofol sedation, but no audio is played. Procedures, timing, and staff interactions are otherwise identical to the music arms.
IRB of Wonkwnag University Hospital
Iksan, South Korea
Dream Incidence (Yes/No) by Modified Brice Interview
Dream occurrence (yes/no) assessed using a neutral modified Brice interview during early recovery in the PACU. Primary comparison: Music-pooled (Preferred or Non-preferred) vs Silence.
Time frame: PACU: primary at 15 minutes (±5) after arrival; if not ready, repeated every 5-10 minutes up to 60 minutes (first valid interview within 60 minutes).
Dream Pleasantness (0-10 Numeric Rating Scale) Among Recallers
Dream pleasantness rated on a 0-10 Dream Pleasantness Numeric Rating Scale (minimum 0, maximum 10), where higher scores indicate more pleasant dreams (0 = not pleasant at all, 10 = extremely pleasant).
Time frame: Same PACU interview window as above: 15 minutes (±5) after PACU arrival; repeated every 5-10 minutes up to 60 minutes until readiness is met (first valid interview within 60 minutes).
Dream Content Metrics (Blinded Coding) Among Recallers
Among participants with dream recall, dream content is assessed using prespecified blinded coding. Metrics include: (a) music-thematic incorporation (present/absent); (b) auditory salience score (0-3; 0 = none, 3 = strong; higher scores indicate greater auditory incorporation); (c) affect valence score (-2 to +2; -2 = very negative, +2 = very positive; higher scores indicate more positive affect); (d) vividness score (0-10; 0 = not vivid, 10 = extremely vivid; higher scores indicate more vivid dreams); and (e) sense of control/agency score (0-10; 0 = no control, 10 = complete control; higher scores indicate greater perceived control/agency). Narratives are double-coded with adjudication for disagreements.
Time frame: PACU interview window: first valid interview within 60 minutes after PACU arrival.
Patient Satisfaction (1-5 Scale)
Patient satisfaction is assessed during early recovery in the PACU using a 5-point Likert satisfaction scale (minimum 1, maximum 5), where higher scores indicate greater satisfaction (1 = very dissatisfied, 5 = very satisfied).
Time frame: PACU (early recovery; within the PACU assessment period).
Intraoperative Mean Arterial Pressure Variability (Standard Deviation)
Variability in mean arterial pressure (MAP) is quantified as the standard deviation (SD) of continuously recorded MAP values during the propofol sedation period. Unit: mmHg. Higher SD indicates greater blood pressure variability. as standard deviation during the sedation period.
Time frame: During sedation (intraoperative period).
Intraoperative Heart Rate Variability (Standard Deviation)
Variability in heart rate (HR) is quantified as the standard deviation (SD) of continuously recorded HR values during the propofol sedation period. Unit: beats per minute (bpm). Higher SD indicates greater heart rate variability.
Time frame: During sedation (intraoperative period).
Total Propofol Dose Administered
Total propofol administered during the procedure is recorded. Dose is expressed as mg/kg (weight-adjusted total dose). Higher values indicate greater propofol exposure.
Time frame: During procedure and immediate recovery period.
Total Opioid Consumption (Morphine Milligram Equivalents)
Total opioid consumption during the procedure and immediate recovery is converted to morphine milligram equivalents (MME) and recorded in mg. Higher values indicate greater opioid exposure
Time frame: During procedure and immediate recovery period.
Vasopressor Use (Yes/No)
Any vasopressor administration during the procedure and immediate recovery is recorded as yes/no. Higher values (yes) indicate that vasopressor support was required.
Time frame: During procedure and immediate recovery period.
Time to Recovery (Aldrete Score ≥ 9) and PACU Length of Stay
Time to achieve Aldrete score ≥9 and total PACU time (minutes).
Time frame: From PACU arrival until discharge criteria met / PACU discharge.
Postoperative Pain Intensity (0-10 Numeric Rating Scale)
Postoperative pain intensity is assessed during early recovery in the PACU using a 0-10 Numeric Rating Scale (NRS; minimum 0, maximum 10), where higher scores indicate worse pain (0 = no pain, 10 = worst imaginable pain).
Time frame: PACU stay (early recovery).
Postoperative Nausea and Vomiting Severity (0-3 Ordinal Scale)
Postoperative nausea and vomiting (PONV) severity is assessed during early recovery in the PACU using a 0-3 ordinal PONV severity scale (minimum 0, maximum 3), where higher scores indicate worse symptoms (0 = none, 1 = mild nausea, 2 = moderate/severe nausea or retching, 3 = vomiting).
Time frame: PACU stay (early recovery).
Postoperative Shivering (Yes/No)
Postoperative shivering during early recovery in the PACU is recorded as present/absent (yes/no).
Time frame: PACU stay (early recovery).
Unplanned Hospital Admission (Yes/No)
Any unplanned hospital admission from procedure start through PACU discharge is recorded as yes/no (higher = yes indicates admission occurred).
Time frame: From procedure start through PACU discharge.
dverse Events (Number of Events)
The total number of adverse events occurring from procedure start through PACU discharge is recorded per protocol (higher values indicate more events).
Time frame: From procedure start through PACU discharge.
Any Adverse Event (Yes/No)
Occurrence of any adverse event from procedure start through PACU discharge is recorded as yes/no (higher = yes indicates an event occurred).
Time frame: From procedure start through PACU discharge.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.