General anesthesia may predispose patients to aspiration of gastroesophageal contents because of depression of protective reflexes during loss of consciousness. The laparoscopy would increase the intra-abdominal pressure, which is regarded as a predisposing factor of gastroesophageal reflux during the anesthesia. The lower esophageal sphincter is the important physiological mechanisms that prevent regurgitation and aspiration. However, the change of LES pressure and gastroesophageal reflux before and after laparoscopic physiological condition is still unknown because the prospective evaluation of gastroesophageal function in human is limited. In addition, the relationship between the change of intra-abdominal pressure and the LES pressure were still unknown, too. In this study, we aimed to observe the changes of gastroesophgeal function parameters by esophageal manometry, pH impedance, and intra-abdominal pressure measured by AbViser ®AutoValve®IAP Monitoring Device before and after laparoscopic condition.

Background: General anesthesia may predispose patients to aspiration of gastroesophageal contents because of depression of protective reflexes during loss of consciousness. The laparoscopy would increase the intra-abdominal pressure, which is regarded as a predisposing factor of gastroesophageal reflux during the anesthesia. The lower esophageal sphincter is the important physiological mechanisms that prevent regurgitation and aspiration. However, the change of LES pressure and gastroesophageal reflux before and after laparoscopic physiological condition is still unknown because the prospective evaluation of gastroesophageal function in human is limited. In addition, the relationship between the change of intra-abdominal pressure and the LES pressure were still unknown, too.

The esophageal manometry has pressure sensor to measure the LES pressure. The AbViser ®AutoValve®IAP Monitoring Device is a sterile non-invasive disposable monitoring device, that is routinely used to measure intra-abdominal pressure (IAP) in the intensive care unit. Therefore, application of esophageal manometry and pH impedance via second-generation SADs may help to detect gastroesophageal functional change and ongoing gastroesophageal regurgitation during perioperative period. We also used the AbViser ®AutoValve®IAP Monitoring Device to monitor the change of IAP before and after laparoscopic condition. In this study, we aimed to observe the changes of gastroesophgeal function parameters by esophageal manometry and intra-abdominal pressure measured by AbViser ®AutoValve®IAP Monitoring Device before and after laparoscopic condition.

Objectives: we aimed to observe the changes of gastroesophgeal function parameters by esophageal manometry, pH impedance, and intra-abdominal pressure measured by AbViser ®AutoValve®IAP Monitoring Device before and after laparoscopic condition.

Patients and methods: Consecutive patients who will receive scheduled laparoscopic surgery under general anesthesia and aged >= 20 will be enrolled. All subjects provide basic demographic data and fill in standard symptom questionnaire for evaluation of baseline upper gastrointestinal symptoms. After induction, the endotracheal tube (ETT) will be inserted to establish airway. Then, the esophageal manometry would be inserted to monitor the LES, and the AbViser ®AutoValve®IAP Monitoring Device will be inserted to monitor the IAP before and after the laparoscopic condition. After the surgery and removal of ETT, the patients will be followed for the oxygen saturation, sore throat or hoarseness in the postoperative care unit, as well as the possible complications.

Expected result: We will observe the changes of LES function, gastroesophageal reflux and the relationship between the IAP and the LES function before and after the laparoscopic condition.

Inclusion Criteria:

• 1. Patients who will receive scheduled laparoscopic surgery under general anesthesia 2. Aged from 20-80 years old

Exclusion Criteria:

- 1. Major systemic disease, such as congestive heart failure, liver cirrhosis, end stage renal disease and malignancy.

2. Patients who have the risk of difficult ventilation or intubation. 3. pregnant women 4. coagulopathy

Patients who will receive scheduled laparoscopic surgery under general anesthesia; Aged from 20-80 years old