Endotracheal tube cuff pressure changes with pneumoperitoneum and steep head down position in patients undergoing robotic urogynecological surgeries – A prospective observational study

Background: The abdominal insufflation in the laparoscopic surgery has been reported to result in an increase in endotracheal tube (ETT) cuff pressure (Pcuff). However, the effect of Trendelenburg, lithotomy and pneumoperitoneum on the ETT Pcuff in robotic urogynaecology surgeries are not well established. Aim: Analyse the changes in ETT cuff pressure during robotic urognaecological surgery. Primary Objective: 1. The changes in ETT cuff pressure after creation of pneumoperitoneum. 2. The changes in ETT cuff pressure after change in position of the patient. Secondary Objectives: 1. To correlate the changes in ETT cuff pressure with airway pressure. 2. To correlate the changes in ETT cuff pressure with BMI. Methods: Sixty patients undergoing elective robotic urogynaecology surgeries were enrolled in the study. ETT Pcuff during different time points was measured and analysed. Also, the change in ETT Pcuff was correlated with the airway pressure (Paw). Results: The difference in ETT Pcuff, before and after lithotomy, pneumoperitoneum and the Trendelenburg position were 1.1 ± 0.7 cmH2O, 4.6 ± 1.0 cmH2O and 1.8 ± 0.8 cmH2O respectively and were statistically significant (probability: P < 0.05). Results obtained after reversing patient position from Trendelenburg position to supine, abdominal deflation and from lithotomy to supine respectively were -2.2 ± 1.4 cmH2O, -4.1 ± 1.0 cmH2O and -0.4 ± 0.8 cmH2O respectively (P < 0.05). The Karl Pearson coefficient of correlation (r) between Pcuff and Paw after lithotomy, pneumoperitoneum, and Trendelenburg position respectively were 0.606, 0.661 and 0.309. Freidman's nonparametric repeated-measures analysis of variance (ANOVA) was used to analyze differences between related Pcuff values over different time points. Overall P value was significant (P < 0.00001). Conclusion: An increase in ETT cuff pressure is seen in robotic laparoscopic surgeries after abdominal insufflation, Trendelenburg position and lithotomy position.