Comparison of incidence of elevated endotracheal tube cuff pressure in elective laparoscopic abdominal surgery using saline or air inflation

Aim: Endotracheal intubation (ETE) procedure, performed to secure the airway during general anesthesia, involves placing a tube into the trachea. The distal end of the tube has an inflatable cuff (balloon) to allow gas exchange and prevent air leaks. After tracheal intubation, symptoms such as sore throat, hoarseness, and difficulty swallowing are reported. An important cause of these symptoms is mucosal damage occurring at the cuff level. Factors such as intra-abdominal and intrathoracic pressure changes and patient position changes, such as pneumoperitoneum application in laparoscopic surgery, along with the use of N20 during general anesthesia, may increase cuff pressure. Many clinical studies are being conducted to control cuff pressure. In our study, we aimed to compare the incidence of cuff pressure increases between tube cuffs inflated with air or saline in elective laparoscopic abdominal surgeries under general anesthesia using N2O. We aimed to compare the incidence of increased cuff pressure between the use of air and saline for inflating endotracheal tube cuffs in patients undergoing elective laparoscopic abdominal surgeries with balanced anesthesia using nitrous oxide. Materials and Methods: Our study was conducted as a prospective observational study on 60 patients between the ages of 18-65 and with ASA physical status I-II who would undergo elective laparoscopic abdominal surgery under general anesthesia. The patients were randomly divided into two groups. Tube cuffs were inflated with air (Group H, n=30) in one group and with saline (Group S, n=30) in the other group. Cuff pressure was continuously monitored with a pressure transducer connected to the cuff balloon using a three-way tap. Sevoflurane and oxygen/N2O (40%/60%) were routinely provided for maintenance of anesthesia in both groups. In all cases where the cuff pressure exceeded 20 mmHg for >30 seconds until the abdomen was insufflated with CO2, the pressure was reduced by intervention. Numbers of interventions were recorded as the primary outcome of the study. The cuff pressures of the patients were recorded after insufflation, before and after being placed in reverse Trendelenburg and Trendelenburg positions.. Results: There was no difference between the groups in terms of cuff pressures measured before and after Trendelenburg. Cuff pressure after Trendelenburg increased significantly in both groups compared to before. Cuff pressures measured after reverse trendelenburg were significantly higher in the air group than in the saline group. Cuff pressures measured after reverse-trendelenburg showed a significant increase only in the air group compared to before. It was determined that the number of interventions performed in the pre-insufflation time intervals was significantly higher in the air group than in the saline group. It was determined that the number of interventions performed in the post-insufflation time intervals was significantly higher in the air group than in the saline group. Conclusion: In elective laparoscopic abdominal surgeries under general anesthesia using nitrous oxide, inflating the ETT cuff with saline required less intervention in intra-cuff pressure than inflating it with air. This result means that when saline is used to create cuff pressure, complications caused by ETT intra-cuff pressure increases may occur less frequently. Therefore, inflation of the ETT cuff with saline may be a safer option for the nitrous oxide general anesthesia method used in elective laparoscopic abdominal surgeries. Key Words: Laparoscopic surgery, cuff pressure, nitrous oxide, incidence of pressure increase.