“…It is also worth mentioning that in some diseases such as stroke, heart attack, gastrointestinal bleeding, seizures, respiratory disorders, anesthesia, head trauma, and loss of blood and body fluids, the tissues of the body do not receive adequate oxygen and this may cause dangerous consequences such as hypoxemia, bruising, and respiratory failure [6][7][8]. On the other hand, improper use of oxygen can lead to irreparable damages to patients, and in some cases may cause death in addition to wasting valuable oxygen resources [2,9,10]. Pulmonary oxygen poisoning, atelectasis, Pickwickian syndrome, visual disturbances, retinal injuries, and blindness are other side effects of oxygen toxicity [11,12].…”