Effect of Binaural Beat Music Played During Knee Arthroplasty With Spinal Anesthesia on Anxiety, Pain and Cortisol Levels.

Knee arthroplasty is one of the most commonly used surgeries in orthopedics. Pain and anxiety are two main problems among patients undergoing orthopedic surgeries.

Being conscious during spinal anesthesia, potential risk, and expectation of postoperative pain contribute to anxiety and fear. Since the patient is fully conscious throughout the procedure, patients undergoing spinal anesthesia are more aware of the noise in the environment. Noise can cause stress, changes in the autonomic nervous system, and increase anxiety.

On the other hand, the surgical procedure itself also causes anxiety in the patient. Fear of surgical failure, lack of knowledge of the anesthesia methodology, possible risks of anesthesia, fear of the unknown, and expected pain during postoperative recovery cause increased anxiety.

The pain and anxiety experienced by surgical patients bring about psychological and physiological changes that significantly affect the course of the surgery, the recovery process, and the prognosis. Anxiety increases cortisol secretion through the autonomic nervous system. However, postoperative anxiety affects the pain response and strengthens the pain perception experienced by the patient. Since the intensity of pain can vary depending on the patient's anxiety, relieving anxiety can also facilitate pain management. Anxiety strengthens the perception of pain, and pain also causes anxiety in patients. In addition, anxiety and pain can reduce patient satisfaction. The irregularity in these psychological and physiological parameters caused by pain and anxiety can be reduced using pharmacological and non-pharmacological interventions. Music-based interventions are non-invasive, economical and non-pharmacological nursing interventions that do not require special skills to be applied, are safe, and also reduce pain and anxiety. Since they do not require a physician's order and have minimal fatal and ethical concerns, they can be easily incorporated into nursing care. Music-based interventions reduce pain and anxiety by distracting attention from stressful events such as pain and anxiety, allowing the music to focus on itself and related experiences/memories, i.e. another stimulus. The anxiolytic effect of music is achieved by suppressing the nervous system due to decreased adrenergic activity and neuromuscular stimulation. Music also stimulates the brain's limbic system to secrete endorphins, providing a sense of well-being. As a result, it reduces pain by increasing endorphin secretion and creating pleasant feelings. Music-based interventions can also reduce anxiety specifically by physiologically acting on the hypothalamic-pituitary-adrenal axis and reducing cortisol levels.

There is increasing interest in music interventions using binaural beats because it normalizes arrhythmias and provides relaxation in surgical patients. Binaural beat music is a therapeutic tool used to reduce anxiety and pain in patients undergoing surgical procedures. It has been reported that binaural beat music is successful as a non-pharmacological treatment method and is more effective than general music in reducing anxiety.