The Effect of Nasal Cannulae During the First 2 Hours Postoperative in Patient

At our institute,during the first 2 hour postoperative, we used to give supplement oxygen via face mask in patient having lung resection surgery. After then if the patient is fine, we'll replace the face mask with nasal cannular untie the next morning. We hypothesized that oxygen mask can be replace by nasal cannular without any hypoxia.