In this study the investigators investigated changes in hemodynamic parameters and cerebral oxygen saturation (rSO2) associated with 10 cmH2O PEEP, which is assumed beneficial for the respiratory functions and oxygenation during the laparoscopic cholecystectomy (LC) applied at the 30°head-up left side position, is compared with using two individual devices (INVOS-FORESIGHT).

Methods: Afterwards the ethics committee approval of the hospital and receiving the written patients' consents, patients to undergo ASA I-II group elective laparoscopic surgery were randomly divided into two groups. Sensors of INVOS and FORESIGHT devices were placed on the right side forehead region. Totally 11 evaluation periods were formed, respectively: Pre-induction (1st Period), post-induction (2nd period), abdominal insufflation outset (3rd period): post-insufflation 5-minute intervals (4th, 5th, 6th, 7th 8th period), end of insufflation (9th period), end of operation (10th period) and end of anaesthesia (11th period). While one of the groups was not applied PEEP(ZEEP), the other group was applied 10 cmH2O simultaneously with the abdominal insufflation proceeding. Demographic data, hemodynamic values and rSO2 values were recorded for both groups at all 11 periods.

Inclusion Criteria:

• ASA(American Society of Anesthesiologist) class I and II
• Patients undergoing laparoscopic cholecystectomy

Exclusion Criteria:

• ASA class III and IV
• Morbid obesity
• Emergency cases
• Cases returned to laparotomy

Patients undergoing laparoscopic cholecystectomy