From the study:
"The musical pieces were selected based on their slow and meditative tempo (60-100 beats per minute), and only non -lyrical instrumental piano or flute based versions were chosen.The flute version which was preferred by most patients was a combination of Raga Yaman and Raga Kirwani. Raga Yaman is bright and uplifting and Raga Kir wani is known for its soothing and calming effects. Combining these two Hindustani classical ragas provides musically uplifting qualities that could be helpful in reducing the stress associated with surgical procedures and control the hemodynamic responses to surgery. Noise cancelling headphoneswere used to play the instrumental pieces at 60db."