Postoperative outcomes of low tidal ventilation in isolated coronary artery bypass graft (CABG) surgeries

This study aimed to evaluate the effects of continuous low tidal volume and low-frequency ventilation during cardiopulmonary bypass (CPB) on postoperative respiratory function, oxygenation parameters, and clinical outcomes. Fifty patients who underwent isolated coronary artery bypass grafting (CABG) at the Department of Cardiovascular Surgery, Akdeniz University Medical Faculty, between September 2024 and March 2025 were prospectively enrolled. Patients were randomly divided into two groups. Group 1 (n=25) received low tidal volume ventilation during CPB (3 mL/kg tidal volume, 6 breaths/min, PEEP 8 cmH₂O, FiO₂ 21%), while Group 2 (n=25) received no ventilation during CPB. Postoperative pulmonary function tests, chest X-ray (CXR) lung scoring, and clinical outcomes including hospital stay, extubation time, and intensive care unit (ICU) stay were evaluated in all patients. In both groups, postoperative FEV₁, FVC, and FEV₁/FVC ratios significantly decreased compared to preoperative values (p<0.05). However, there was no statistically significant difference between the groups regarding these respiratory parameters (p>0.05). No significant differences were observed between the groups in terms of extubation time, ICU stay, or inflammatory markers. Conversely, the duration of hospital stay was significantly shorter in the ventilated group (p<0.05). Although low tidal volume ventilation during CPB did not result in significant improvement in respiratory function, it was associated with a shorter hospital stay, suggesting a potential contribution to enhanced clinical recovery. As a low-risk and feasible strategy, this ventilation approach may be considered in routine cardiac surgical practice. Further large-scale studies, including advanced biomarker monitoring, are warranted to more clearly determine its clinical effectiveness.