Effects of intraoperative open-lung strategy on cardiopulmonary function in frail elderly patients undergoing laparoscopic surgery: a randomized controlled trial.

PURPOSE: This study aimed to investigate the potential effects of intraoperative open-lung strategy (OLS) on pulmonary function and cardiac function in elderly frail patients. METHODS: 104 frail elderly patients were randomly assigned into non-OLS group [small tidal volume (VT) + 5 cm H2O positive end-expiratory pressure (PEEP)] and OLS group [small VT + stepwise recruitment maneuvers (RM) + individualized PEEP]. Primary outcomes assessed were intraoperative cardiopulmonary function indices and incidence of postoperative pulmonary complications. Secondary outcomes included postoperative myocardial injury markers and recovery outcomes. RESULTS: Eighty-one patients completed the final analysis. The OLS group showed significant improvements in arterial oxygen pressure (PaO2), PaO₂/FiO₂ ratio, and pulmonary dynamic compliance (Cdyn) from the peak of lung recruitment to the end of surgery (T1-T4). The overall incidence of postoperative pulmonary complications (PPCs) also significantly decreased (P<0.05). Compared with the non-OLS group, left ventricular ejection fraction (LVEF), stroke volume (SV), early mitral inflow velocity to early mitral annular velocity ratio (E/E ‘), left ventricular global longitudinal strain (LVGLS), and plane systolic offset of mitral and tricuspid annular plane were significantly decreased at T1 in the OLS group (P<0.05), and recovered at T3. No significant change in the expression of myocardial injury markers between the two groups (P > 0.05). The postoperative recovery outcomes of OLS patients was significantly shortened (P<0.05). CONCLUSION: The application of OLS can effectively improve intraoperative respiratory mechanics and oxygenation in frail elderly patients, reduce the occurrence of PPCs, and shorten hospital stays of patients, without continuous negative impact on cardiac function. TRIAL REGISTRATION: Retrospectively registered; Chinese Clinical Trial Registry, www.chictr.org.cn , number: ChiCTR2200058783; Registered on April 17, 2022.