Vital signs of postoperative patient are monitored intensively in post-anesthesia care unit or intensive care unit, but the frequency of surveillance decreases in typical surgical wards. The continuous pulse oximetry in surgical wards is known to be useful in detection and prevention of hypoxemia, reducing complications caused by postoperative respiratory depression. However, continuous monitoring is not conducted, due to shortage of equipment and personnel. Recently, wearable device for measuring pulse oxygen saturation, which is inexpensive, applicable to patients with mobility, and can be monitored continuously through wireless connection, has been supplied. In this study, the investigators evaluate the effect of continuous monitoring of oxygen saturation with wireless device(MASIMO Radius-7) on postoperative patients who are transferred to general wards, and evaluate the effect of early intervention in reducing the event of hypoxemia.

Inclusion Criteria:

• Patients undergoing noncardiac surgery under general anesthesia
• American Society of Anesthesiologists (ASA) physical status class I-III

Exclusion Criteria:

• Patients refusing to participate in the study
• Patients under emergency surgery
• Patients who wearable device is not applicable
• Patients scheduled to be transferred to intensive care unit
• Patients scheduled to receive oxygen supplementation in surgical ward
• Patients scheduled to undergo continuous pulse oximetry monitoring