Differential lung ventilation versus continuous positive airway pressure to improve oxygenation during one lung ventilation in thoracoscopic sympathectomy

Background: One lung ventilation (OLV) offers the optimal surgical field exposure in thoracoscopic sympathectomy. Nevertheless, insufficient gas exchange and hypoxemia are frequent issues during OLV. Objective: To investigate the impact of employing differential lung ventilation (DLV) or continuous positive airway pressure (CPAP) on peripheral oxygen saturation during OLV in thoracoscopic sympathectomy. Methodology: This prospective, randomized controlled clinical study enrolled 60 patients scheduled for elective thoracoscopic sympathectomy. Patients were randomly assigned to one of three groups; Group A (OLV) (control group) the lung in the operated side will remain opened to atmosphere, Group B (OLV + CPAP group) the lung in the operated side will be connected to CPAP will be set to 5 cmH2O. and Group C (OLV + DLV group) the lung in the operated side will be connected to a small portable ventilator that will be set at a rate of 8breaths per minute, inspired gas 100%oxygen, peak pressure and tidal volume will be set to the lowest available values to result in a peak pressure of 10 cmH2O and a tidal volume around 100ml. Results: Oxygen saturation showed a significant difference among the groups after 10min from establishing OLV with the highest peripheral arterial oxygen saturation (SpO2) in group C followed by group B then group A but no significant difference among groups in SpO2 at initiation of OLV and after reestablishing two lung ventilation. Also, highest grades of surgeon satisfaction were noticed in group B followed by group C then group A (p= 0.008). No significant difference was noted among the groups, with respect to airway pressures, hemodynamic parameters, and postoperative complications. Conclusion: Differential lung ventilation showed superior efficacy on maintaining peripheral oxygen saturation during OLV in thoracoscopic sympathectomy compared to CPAP, but CPAP showed better surgeon preference over DLV. Both DLV and CPAP can be used safely and effectively without significant hemodynamic alterations.