Recruitment Maneuver

Right ventricular failure (RVF) is a common complication to cardiac surgery, which is associated to mortality, kidney failure, stroke, prolonged mechanical ventilation and ICU stay. The right ventricle is particularly vulnerable to an increased afterload. By increasing pulmonary vascular resistance (PVR), atelectasis might mitigate a negative effect on the right ventricle. Recruitment maneuvers have been shown to resolve atelectasis and improve hemodynamics by increasing cardiac output and lowering PVR. However these maneuvers transiently raise airway pressures, which in turn increases right ventricular afterload, a situation often poorly tolerated by patients with RVF. Prone position is used in patients with respiratory failure and has been shown to decrease mortality in patients with ARDS. Prone position decreases atelectasis and moves ventilation dorsally. In ARDS it also seems to mediate beneficial hemodynamic effects such as an increase in cardiac output and a decrease in PVR. The investigators hypothesis is that prone position early after cardiac surgery will increase cardiac output by recruitment of atelectasis and thereby decrease PVR.

This is a prospective, single-center, double-blind, randomized controlled trial designed to investigate the individual differences in recruitment efficacy and safety between personalized lung recruitment pressure based on esophageal pressure and conventional fixed lung recruitment pressure. The intervention involved calculating personalized lung recruitment pressure using inspiratory and expiratory esophageal pressures measured via a transnasal esophageal balloon catheter, which was then compared with a fixed pressure of 30 cmH₂O, each applied to maintain a single-cycle lung recruitment maneuver for 10 seconds. A total of 90 patients undergoing elective tracheal intubation under general anesthesia for head-down laparoscopic surgery were randomly assigned to either the experimental or control group. The primary outcome was post-recruitment lung compliance, and secondary outcomes included driving pressure, peak airway pressure (Ppeak), modified LUS score, gas exchange indices, hemodynamic parameters, length of stay in PACU after extubation, incidence of postoperative pulmonary complications (PPCs) on day 3 after surgery, and the rate of non-surgical antibiotic use.