Effects Of Different Oxygen Concentrations On Atelectasis Monitored By Lung Ultrasound Under One-lung Ventilation

Objectives:To observe the effects of different inspired oxygen concentration during one-lung ventilation on perioperative atelectasis in patients undergoing thoracoscopic lobectomy through lung ultrasound,and to explore the appropriate inhaled oxygen concentration during one-lung ventilation,so as to provide reference regarding the application of reasonable inhaled oxygen concentration during one-lung ventilation.Methods:Select 90 patients scheduled for elective thoracoscopic lobectomy under general anesthesia,and divide them into 3 groups by random number table（n=30 cases in each group）,Fi O₂=40%during one-lung ventilation in group A,Fi O₂=60%during one-lung ventilation in group B,and Fi O₂=100%in group C during one-lung ventilation.Patients in the three groups were pre-oxygenated with 100%inspired oxygen concentration,lung recruitment maneuver was performed after successful intubation,ventilator parameters were adjusted according to the lung protective ventilation strategy,and finally the inspired oxygen concentration during one-lung ventilation was adjusted according to the grouping.Before induction of anesthesia（T₀）,10 minutes before the operation（T₁）,and 10 minutes after the operation（T₂）,the lung ultrasound of the unoperated lung was performed and the modified lung ultrasound score was performed.Monitor and record the following data:（1）general patient information:gender,age,height,weight,body mass index（BMI）;（2）before induction of anesthesia（T₀）,10 minutes before the operation（T₁）,and 10 minutes after the operation（T₂）,ultrasound score of the unoperated lung to assess whether there is atelectasis;（3）record anesthesia time,operation time,and one-lung ventilation time;（4）record the location of the ventilated lung,and the highest airway peak pressure(P_peak)during one-lung ventilation and the lowest oxygen saturation（Sp O₂）during one-lung ventilation;（5）record bedside chest X-ray results on the first day after surgery;（6）special events during surgery.Results:1.Minimum oxygen saturation during one-lung ventilation:There was no statistically significant difference in the minimum oxygen saturation during one-lung ventilation among groups A,B,and C.2.Total score of lung ultrasound score:10 minutes before the operation（T₁）and 10 minutes after the operation（T₂）,the difference of the total lung ultrasound score among the three groups was statistically significant（P<0.05）.There was a statistically significant difference between groups A and B compared with group C（P<0.05）.3.Incidence of atelectasis:At the two time points of T₁ and T₂,there was a statistically significant difference in the incidence of atelectasis among the three groups（P<0.05）.There was no statistically significant difference between groups A and B（P>0.05）.At two time points,there were statistically significant differences between groups A and B and group C（P<0.05）.4.Incidence of atelectasis:At the two time points of T₁ and T₂,there was a statistically significant difference in the incidence of atelectasis among the three groups（P<0.05）.At the two time points of T₁and T₂,the differences between groups A and B and group C were statistically significant（P<0.05）.5.There was a statistically significant difference in the incidence of postoperative pulmonary inflammation between groups A,B,and C（P<0.05）.There was a statistically significant difference in the incidence of postoperative pulmonary inflammation between group A and group B（P<0.05）.There was a statistically significant difference in the incidence of postoperative pulmonary inflammation between group A and group C（P<0.05）.Conclusions:1.Inhalation of 40%oxygen concentration during one-lung ventilation reduces the incidence of intraoperative atelectasis and postoperative pulmonary complications,while not significantly increasing the incidence of intraoperative hypoxemia,and can be safely used during one-lung ventilation middle.2.Inhalation of 60%oxygen concentration during one-lung ventilation is beneficial to reduce the incidence of intraoperative atelectasis,but does not significantly reduce the incidence of postoperative pulmonary complications.3.While inhaling 100%oxygen concentration during one-lung ventilation does not significantly reduce the incidence of intraoperative hypoxemia,it significantly increases the incidence of intraoperative atelectasis and postoperative pulmonary complications,so it is not recommended for one-lung ventilation.