Preventing pulmonary complications after laparoscopic colorectal surgery: a lung-protective protocol vs. standard care

BACKGROUND Placing patients in the steep Trendelenburg position with a pressurised pneumoperitoneum during laparoscopic colorectal surgery increases pulmonary airway pressure, increasing the risks of lung injury and postoperative pulmonary complications, even in patients with healthy lungs. OBJECTIVES The aim was to determine whether an integrated anaesthesia protocol was superior to traditional protective ventilation in terms of preventing pulmonary complications. DESIGN This study used a randomised, controlled, parallel-group design. SETTING This single-centre trial was conducted at the National Cancer Centre/Cancer Hospital of the Chinese Academy of Medical Sciences from January to May 2023. PATIENTS A total of 120 patients who underwent laparoscopic surgery for colorectal cancer with intermediate to high risk of pulmonary complications, as determined by the Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) score. INTERVENTIONS Participants were randomly assigned to either lung protective ventilation with a tidal volume of 6 ml kg −1 of predicted body weight + deep neuromuscular block (a train-of-four count of 0 and post tetanic of 1 to 2) + low peritoneal pressure (10 mmHg) or conventional pulmonary ventilation with a tidal volume of 8 ml kg −1 of predicted body weight + moderate neuromuscular block (a train-of-four count of 1 to 2) + standard peritoneal pressure (15 mmHg). MAIN OUTCOME MEASUREMENTS The primary outcome was the incidence of pulmonary complications within 30 postoperative days. The secondary outcomes included serological biomarkers of lung injury. RESULTS The lung protective group had a significantly lower incidence of pulmonary complications (15.0%) than the conventional group (38.3%; hazard ratio, 0.332; 95% CI, 0.153 to 0.718; P = 0.003). There were no significant differences in the plasma biomarker levels of soluble receptor for advanced glycation end products and angiopoietin-2 for lung injury between the groups. The treatment-by-covariate interactive analysis revealed that the lung-protective strategy conferred considerable benefits for males and individuals aged 60 years or above. A nomogram that predicted pulmonary complications incorporating four variables exhibited a strong discriminative performance, and the results of the decision curve analysis revealed the potential clinical value of this nomogram. CONCLUSION Compared with traditional strategies, the integrated lung-protective approach may mitigate pulmonary complications without causing lung injury in intermediate to high-respiratory-risk patients undergoing laparoscopic colorectal surgery. TRIAL REGISTRATION Chinese Clinical Trial Register Identifier: ChiCTR2100054215