Effects Of Different Fraction Of Inspired Oxygen On Perioperative Lung Function In Patients With Diabetes And Microangiopathy

Objective:To evaluate the effect of different fraction of inspired oxygen（FiO₂）in mechanical ventilation on perioperative lung function in patients with diabetes and microangiopathy.Methods:60 patients with diabetes and microangiopathy undergoing elective laparoscopic radical gastrectomy were divided into 3 groups（n=20）using a random number table method.FiO₂was 35%of group A,50% of group B and 75%of group C.It was recorded of the vital signs,such as heart rate（HR）,systolic pressure（SBP）,diastolic pressure（DBP）,pulse oxygen saturation（SPO₂）before induction of anesthesia（T₀）,30 min after pneumoperitoneum（T₁）,60 min after pneumoperitoneum（T₂）,and 10 min after the end of pneumoperitoneum（T₃）.And the oxygenation index（OI）,Intrapulmonary shunt rate（Qs/Qt） was calculated.At the end of the operation,time duration to reach the indications for tracheal extubation and postoperative period in the postanesthesia care unit （PACU）was recorded.And postoperative 7-day incidence of pulmonary complications（hypoxemia,pneumonia,respiratory failure） was compared too.Results:Compared with group C,the duration to reach the indications for tracheal extubation was significantly reduced in group A and B（P<0.05）,and there was no statistically significant difference between group A and B（P>0.05）.The level of SPO₂ had no statistically significant difference at T₀ among the three groups（P>0.05）,and group A was lower than group B and C at T₁,T₂and T₃（P<0.05）.There was no significant difference between group B and group C at T₁,T₂and T₃（P>0.05）.Compared with group B,the OI of group A and C at T₁,T₂and T₃was significantly lower（P<0.05）.In each group,the OI of T₁,T₂and T₃was lower than T₀（P<0.05）.There was no statistical significance in Qs/Qt among the three groups at T₀（P>0.05）.But compared with group C,the Qs/Qt of group A and B was lower at T₁,T₂and T₃（P<0.05）.In the intra-group comparison,Qs/Qt at T₀was lower than that of T₁～T₃（P<0.05）.Conclusion:For patients with diabetes and microangiopathy undergoing laparoscopic radical gastrectomy,the 50% fraction of inspired oxygen during mechanical ventilation has little influence on the perioperative lung function.