High anxiety levels may lead to negative outcomes, and previous studies have shown that music listening could reduce periprocedural anxiety and depression. Recent evidence suggests that a lower heart rate variability (HRV) may be associated with anxiety and depression disorders, but the association of these HRV parameters with preoperative mood in the procedural settings are less defined.

In this prospective cohort pilot study, the study team will investigate the association between HRV and psychological vulnerability (anxiety, depression) in the presence of music listening before procedures. A total of 120 patients about to undergo procedures (surgery, procedures) will be recruited in three healthcare institutions in Singapore (KK Women's and Children's Hospital, Singapore General Hospital, Changi General Hospital). Patients will be asked to have their ECG readings recorded before, during, and after music listening. Preprocedural information (e.g., demographic, clinical) and psychological scores will be collected.

Autonomic nervous system (ANS) comprises two opposing components: sympathetic nervous system (SNS) and parasympathetic nervous system (PNS). It is reported that alterations in the balance between SNS and PNS activity may be related to anxiety and depression. SNS and PNS activity can be non-invasively quantified using HRV, the fluctuation in time intervals between adjacent heartbeats. HRV may be obtained from ECG readings to derive the indices of the variability in time and frequency domains. A meta-analysis in patients with anxiety disorders demonstrated that HRV parameters including root mean square of successive differences (rMSSD), standard deviation, and high frequency HRV (HF-HRV, 0.15-0.4Hz) was lower as compared with healthy individuals.

Compared to the conventional use of pharmacological drugs, music listening is proven to be safer and more cost-effective, reduce perioperative pain, and improve patient satisfaction. Furthermore, music listening can modulate the patient's inflammatory response to reduce anxiety, which could help distracting patients from focusing on negative thoughts of the impending surgery, a major source of anxiety. By providing a source of serenity and calmness through music, patients can divert their attention to and focus less on feelings of anxiety and fear.

The study team therefore proposes to record HRV parameters before, during and after music listening and compare the readings against the psychological scores collected as part of the study. This would facilitate the understanding in the association between HRV and psychological aspects in surgical settings. The overall aim is to develop an individualised, targeted approach to understand the relationship between HRV and mood, and how the improvement in HRV parameters in the presence of music listening may help to improve perioperative experiences.

Inclusion Criteria:

1. America Society of Anaesthesiologist (ASA) 1 to 3 adults undergoing procedures (surgery, pain procedures);
2. Able to read and understand English and/or Chinese;
3. Not receiving opioid prior to the procedures.

Exclusion Criteria:

1. With chronic pain;
2. Opioid and drug abuse;
3. Scheduled postoperative Intensive care unit (ICU) admission;
4. With baseline non-sinus heart rhythm or on pacemaker support.

To be shared upon request