Aim: To evaluate the effect of bed rest with music on relaxation for patients who have undergone heart surgery on postoperative day one.

Background: Music intervention has been evaluated as an appropriate nursing intervention to reduce patients 'pain, stress and anxiety levels in several clinical settings, but its effectiveness in increasing patients' subjective and objective relaxation levels has not been examined.

Design: A randomised controlled trial.

Method: Forty patients undergoing open coronary artery bypass grafting and/or aortic valve replacement surgery were randomly allocated to either music listening during bed rest (n = 20) or bed rest only (n = 20). Relaxation was assessed during bed rest the day after surgery by determining the plasma oxytocin, heart rate, mean arterial blood pressure, PaO2 SaO2 and subjective relaxation levels.

Results: In the music group, levels of oxytocin increased significantly in contrast to the control group for which the trend over time was negative i.e., decreasing values. Subjective relaxation levels increased significantly more and there were also a significant higher levels of PaO2 in the music group compared to the control group. There was no difference in mean arterial blood pressure, heart rate and SaO2 between the groups.

Conclusion: Listening to music during bed rest after open-heart surgery has some effects on the relaxation system as regards s-oxytocin and subjective relaxations levels. This effect seems to have a causal relation from the psychological (music makes patients relaxed) to the physical (oxytocin release).

Relevance to clinical practice: Music intervention should be offered as an integral part of the multimodal regime administered to the patients that have undergone cardiovascular surgery. It is a supportive source that increases relaxation.