In this video, Dr. K K Aggarwal, President Heart Care Foundation of India and Group Editor in Chief MEDtalks, will explain about oxygen desaturation index. The oxygen desaturation index (ODI) is typically measured as part of standard sleep studies, such as a diagnostic polysomnogram. It is done in person’s with heavy snoring with sleep obstructive apnea. It is in how many hours the person develops a oxygen desaturation level of more than 4 %. He will further explain the evaluation of such patients.