Influence Of The Position Of Double-lumen Endobronchial Tube On The Efficacy Of Lung Separation And Ventilationpostgraduate

Objective:This study compares the differences caused bypatients’ postureondouble-lumen endobronchial tubes (DLT)position, and evaluate the displacement of DLTeffectson lung isolation to assess whether bodyposturechanges would cause DLT displaced when DLT in the healthy side or affected side to offer clinical practice on adjustment of DLT position.Method:Patients (n=44) who plan for elective thoracotomy or thoracoscope surgery under one-lung ventilation (OLV). They were randomized into 2 groups:DLTplaced in the group (V-DLT,n=23) or innone-ventilation side group (O-DLT,n=21). Patients wereoffered intravenous fluids pathway, monitered byelectrocardiogram (ECG), pulse oxygen saturation, the radial artery puncture catheter for arterial pressure, central venous catheter. carbon dioxide of expiration. Anesthesia induction use midazoiam 0.05 mg/kg.0.5 ugkg sufentanil or ientanyl 3-4 ug/kg, etomidate 0.15-0.3 mg/kg. androcuronium 0.6 mg/kg. Anesthesia sustain continuously pumpspropofol2-5 mg/kg/h. remifentanyl 0.1-0.3 pg/kg min by intravenous injection.sevoflurane 1% for combined anesthesia, intravenous intermittent dosing ofvecuronium bromide 0.05 mg/kg on 0.1-0.2 mg/kg atracuriun; DLT is chosen base on patients’ factors such as height. weigh, chest radiographie data After anesthesia induction, patients wereintubationwithDLTand undergoing mechanical ventilation. Double lung ventilation’s total volume is set to 6-8 ml/kg. 10-14 times/min as breath frequency:Total volume for one-lung ventilation is 5 to o ml/kg,18 to 20 times/min as breath frequency. Fiberopticbronchoscopyis used to relocate, measure DLT’position after auscultation, and record the peak inflation pressure in double lung orone lung ventilation. Same methods are repeated after patients’posture change from supine to lateral positon.Results:Two groups of patientshave no statistically significant difference in gender, age, weight, height (p>0.05). There is no statistically significant difference in choosing L-DLT or R-DLT. diameter 35F and 37F between the two groups (p> 0.05). Compared with supine. DLT remained the ideal position inthe affectedgroupis higher than the other group (p> 0.5). After position change, the distance rang of the healthy group is (-3.4±13mm), while the affected group is(-3.2±7mm). There is statistically significant between them (p< 0.5).Peak inflation pressure changes after position change, the affected group is lower than the healthy group (p< 0.05). Lung isolation effect after two groups of position changes affect the result comparison, the affcted set is 19%, and the healthy set is 38%. The healthy group tend to have more uncomplete lung isolation than the affectd group (p<o.05).Conclusion:Position change cause misplacement of DLT and have effect on lung isolation inthoracie surgery. Timely use FOB adjust DLT position can improve pulmonary ventilation, avoid the hypoxemia caused by mild uncomplete lung isolation. DLT seems to move out when position is changed from potion to.lateral position, and it in healthy side moves longer than the other group. When FOB isnotavailable, the cliniciancan try to move DLT5 mm inward, or in the first positioning DLTfixed endotracheal tube5 mm deeper than the standard position under the condition of no changes on lung isolation.