Abstract PR577

Abstract

Background & Objectives: Robotic assisted surgery (RAS) has become extensively used during the last decade in major abdominal surgery. As surgical interventions are more complicated and patients much older and with more severe co-morbidities we aimed to investigate the effects of patients positioning on lung ventilation during RAS. Materials & Methods: We prospectively included 50 patients undergoing RAS under general anesthesia during a four months period in a single center. Patients demographic data and ventilatory parameters (lung compliance – C, plateau pressure – Pplat, minute volume – MV and respiratory rate - RR) and arterial blood gas analysis (oxygen pressure – PaO2 and carbon dioxide pressure – PaCO2) were recorded after induction of anesthesia (T0), after induction of pneumoperitoneum (T1) and on an hourly basis until the end of surgery. Normocapnia was defined as a PaCO2 between 35 and 45 mmHg. Results: Of the 50 patients analyzed, 52% (n=26) underwent RAS in Trendelenburg (T) position and 48% (n=24) in steep Trendelenburg (sT) position. We observed a significant decrease in C between T0 and T1 (from 42.5±11.5 ml/cmH2O to 26.7±6.3 ml/cmH2O, p=0.001) and an increase in Pplat (from 16.1±5.1 cm H2O to 23.6±5.54 cm H2O, p=0.001). No correlation was found between patient positioning and the decrease in C (p=0.567) and increase in Pplat (p=0.652). Patients in T position required a mean MV of 8.4±1.4 L/min then those in sT of 8.5±2.5 L/min in order to maintain normocarbia (p=0.897) but a slightly lower RR (15.5±2 versus 17.5 ±1, p=0.035). Conclusion: Conclusion. The effects of patient position on lung ventilation during RAS are minimal al best and show no clinical relevance. The significant decrease in lung compliance and increase in plateau pressure observed may be determined by other factors that need further investigation. Disclosure of Interest: None declared