Effect of Mask Ventilation on Surgical Field View in Robotic Colorectal Surgery

Following anaesthesia induction, mask ventilation is a technique applied until successful tracheal intubation is achieved. It is known that with mask ventilation, air can also enter the stomach as well as the trachea. If mask ventilation is not performed with the correct technique during robotic surgery, excessive dilation of the stomach will impair the surgical team's vision, causing the operation to be more difficult and longer. In this study, we aimed to demonstrate the effects of mask ventilation and non-mask ventilation on gastric dilatation, increased bowel movements, bowel distension and surgical vision in robotic colorectal surgeries. In our anaesthesia practice, patients will be premedicated with 0.03 mg/kg midazolam in the preoperative area and then taken to the operating room. After standard monitorization in the operating room, preoxygenation will be applied with end tidal oxygen (EtO2) monitoring. Patients whose EtO2 value reached 90% will be divided into two groups and the following protocol will be applied; No mask ventilation group: 2 mcg/kg fentanyl, 1 - 2 mg/kg propofol, 1 mg/kg rocuronium will be administered for anaesthesia induction. Orotracheal intubation will be performed at 60 seconds with video laryngoscopy without ventilation other than spontaneous breathing. Mask ventilation group: 2 mcg/kg fentanyl, 1 - 2 mg/kg propofol, 1 mg/kg rocuronium will be administered for anesthesia induction. Mask ventilation will be performed with mechanical ventilator set to pressure controlled ventilation, 15 cmH20 peak pressure, 10 respiratory rates per minute. Orotracheal intubation will be performed at the 60th second with video laryngoscopy. The surgical team, who is blinded to the anesthesia induction groups, will mark the Likert scale prepared for the presence of gastric distension, presence of intestinal distension, status of bowel movements and surgical vision regarding the intraoperative process. Surgical time will also be recorded at the end of the operation.