Some studies have suggested that nausea and vomiting are the most common postoperative complications and about 20 to 30% of postoperative patients have this problem [17]. According to types of surgery, anesthesia or surgical site may result in different complications. Postoperative nausea and vomiting can change because of taking medicine, ages and other factors. In the current medical environment, the above complications may be due to lack of medical manpower or new medical staff experience is not enough. Therefore, they overlook symptoms of postoperative complications. In order to reduce postoperative nausea and vomiting occurs, this study designed to use somatosensory detection combined with decision tree to create a patient's monitoring system. Through the infrared of the body sensor, it will detect the patient's trajectory and joint angle to the coordinates for recording and compared to each change in the coordinates and the establishment of the Case-Based Reasoning (CBR) as a Posture And the Management of Action Data through the CBR reasoning technology, deduced the possible situation and then the decision tree algorithm for the final abnormal situation determines whether the action is abnormal and return the results. In addition, through the patient's monitoring system. identify the skeleton and face in order to determine whether the patient wake up so that medical staff can early provide appropriate medical care and to achieve better medical quality before the event of an emergency or a waking up patient by detection.