Prevention of Postoperative Respiratory Complications

Given the huge number of patients mechanically ventilated during general anaesthesia, optimizing alveolar recruitment by limiting pulmonary and systemic aggression is a key objective for further progress in perioperative patient management.

During general anaesthesia, ventilation disorders with atelectasis, derecruitment of posteroinferior zones and reduced functional residual capacity (FRC) occur in relation to the operative position, the effect of neuromuscular block and general anaesthesia. These conditions of poor pulmonary aeration favor postoperative respiratory complications and are responsible for excess mortality in the perioperative period.

Alveolar recruitment maneuvers (ARMs) are ventilatory strategies used during general anesthesia that aim to restore lung aeration with Positive End Expiratory Pressure (PEEP) sufficient to keep the lungs open afterwards. This pulmonary hyperinflation not only has a major impact on hemodynamics but also presents a risk of barotrauma. ARM is currently performed without precise measurement of the pressures prevailing in the lung.

Advanced monitoring is now available and integrated into the latest-generation ventilators and includes the combination of Transpulmonary pressure (TPP) and Electro-Impedance Tomography " (EIT) measurements.

The aim of this observational study is to measure and record advanced respiratory monitoring data in a minimally invasive way, during alveolar recruitment tests routinely performed for the target population (obese, prone, laparoscopic surgery). Describe and a posteriori analyze the recorded data and establish a relationship between the PEEP values set by conventional ARM and those determined by advanced monitoring combining EIT and PTP for the same patient.