Clinical Study On Measuring The Length Of Right Main Bronchus For Predicting The Effect Of Bronchial Blocker For Left Lung One-Lung Ventilation

Objective:Measuring and according to the length of right main bronchus?RMB?for predicting the effect of bronchial blocker?BB?for left lung one-lung ventilation?OLV?,which provided a theoretical basis for anesthesiologist to select BB reasonably for lung isolation.Methods:46 patients scheduled for undergoing thoracoscopic right pulmonary lobectomy were selected,who were ASA grade I^II,male or female,age 30 to70 years,BMI 19 to 29 kg/m².According to the preoperative chest CT scanning image of the patient,the length of RMB is measured by using airway multiplanar reconstruction?MPR?technique,patients with RMB length?1.5cm were included in group A,patients with RMB length>1.5cm were included in group B.There were 24 patients in group A and 22 patients in group B.The two groups of patients were anesthetized by the same anesthesiologist using the same general anesthesia method.First,a single-lumen endotracheal tube was inserted,and then BB was placed under the guidance of the electronic bronchoscope into the opening of RMB to make it as completely as possible to block the RMB,and the BB was fixed after the position was determined.After the patient was changed to left lateral position,bronchoscope was used to reconfirm the position of the airbag.When OLV is performed,inflate the airbag of BB to block the RMB.The breathing pattern and parameter setting of the two groups were the same,and the parameters were unchanged after OLV.The data of the two groups of patients were observed and recorded including?1?Positioning time of bronchoscope;?2?Lung collapse time;?3?Number of cases the BB displaced;?4?Excellent and good rate of operating field exposure;?5?The arterial partial pressure of oxygen?PaO₂?and peak airway pressure?Ppeak?were recorded at 10min during two-lung ventilation?T₁?and 30min?T₂?,60min?T₃?during one-lung ventilation.Results:In this experiment,2 patients in group A had a short length of RMB,and the airbag of BB was frequently displaced during bronchoscope positioning.It was not possible to place it in a suitable position to block the RMB opening,so it was replaced with a left double-lumen endobronchial tube?DLT?before surgery.After exclusion,group A and group B were included in 22 patients respectively.There was no significant difference in sex,age,BMI and operative site between the two groups?P>0.05?.?1?The positioning time of bronchoscope in group B was shorter than that in group A,the difference was statistically significant?P<0.05?;?2?The lung collapse time in group B was shorter than that in group A,the difference was statistically significant?P<0.05?;?3?The number of cases the BB displaced in group B was less than that in group A,the difference was statistically significant?P<0.05?;?4?The excellent and good rate of operating field exposure in group B was higher than that in group A,the difference was statistically significant?P<0.05?.?5?There was no significant difference in PaO₂ at T₁ between group A and group B?P>0.05?;The PaO₂ at T₂ and T₃was lower than that at T₁ in both group A and group B,the difference was statistically significant?P<0.05?;The PaO₂ at T₂ was lower than that at T₃ in both group A and group B,the difference was statistically significant?P<0.05?;The PaO₂ at T₂ and T₃in group B was higher than that in group A,the difference was statistically significant?P<0.05?;There was no significant difference in Ppeak at T₁between group A and group B?P>0.05?;The Ppeak at T₂ and T₃ was higher than that at T₁ in both group A and group B,the difference was statistically significant?P<0.05?;The Ppeak at T₂ and T₃ in group B was lower than that in group A,the difference was statistically significant?P<0.05?.Conclusion:The clinical effect of using BB for left lung OLV in patients with RMB length>1.5cm was significantly better than that in patients with RMB length?1.5cm;Patients with RMB length>1.5cm are more suitable to use BB for left lung OLV;Preoperative measure the length of RMB can predict the clinical effect of using BB in left lung OLV to a certain extent.