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

The goal of this clinical trial is to demonstrate the effects of pressure-controlled mask ventilation and non-mask ventilation during anaesthesia induction on gastric insufflation, gastric dilatation, increased bowel movements and bowel distension and to demonstrate its effect on surgical vision in robotic colorectal surgeries. The main questions it aims to answer are: How will non-mask ventilation during anaesthesia induction effect surgical vision in robotic colorectal surgeries compared to mask ventilation? How will non-mask ventilation during anaesthesia induction effect gastric dilatation and bowel movements in robotic colorectal surgeries compared to mask ventilation? If there is a comparison group: Researchers will compare mask ventilation and non-mask ventilation during anaesthesia induction to see if the surgical vision, gastric dilatation and bowel movements are effected. Participants will be divided in two groups: No mask ventilation group: Outside of spontaneous breathing during preoxygenation, orotracheal intubation will be performed at the 60th second after anesthesia induction without ventilation, using video laryngoscopy. Mask ventilation group: After anesthesia induction, mask ventilation will be performed with a respiratory rate of 10 and 15 cmH2O pressure, followed by orotracheal intubation using video laryngoscopy at the 60th second. Researchers will compare the results between the groups to see the surgical vision, gastric dilatation and bowel movements. The hypothesis of this study is that non-mask ventilation will provide better surgical vision, less gastric dilatation and less bowel movements in robotic colorectal surgeries.