One-lung Ventilation With Additional Ipsilateral Ventilation Of Low Tidal Volume And High Frequency In Completely Thoracoscopic Lobectomy

Objective: To investigate the ventilatory function and lung protection effect of one-lung ventilation with additional ipsilateral ventilation of low tidal volume and high frequency in completely thoracoscopic lobectomy.Methods: 1.67 cases of early non-small cell lung cancer patients who received thoracoscopic lobectomy in our hospital from December 1st,2014 to May 1st,2016 were enrolled in our study.The patients were randomly divided into 2 groups: traditional one-lung ventilation method（CV,n=33）and one-lung ventilation,low tidal volume ventilation with high frequency in ipsilateral lung group（LV,n=34）using the digital random table method.（1）Inclusive criteria: a.ASA I II;b.Before surgery,enhanced chest CT,abdominal B ultrasound,magnetic resonance imaging of the brain,radiation examination of the important organ of whole body confirming that the tumor did not transfer;c.Karnofsky（card status）score> 70 points,did not receive surgery and chemotherapy;d.No history of long-term smoking.Heart,liver,kidney function without exception.（2）Exclusion criteria: a.Preoperative Pulmonary Function: Percentage of forced vital capacity for the first second（FEV1.0 / FCV %）<50%;preoperative blood oxygen saturation was less than 93%;The preoperative arterial partial pressure of oxygen was less than 70 mm Hg and the arterial partial pressure of carbon dioxide was greater than 50 mm Hg;b.Preoperative cardiac function grade III or IV;c.With a serious history of heart and lung disease and cerebrovascular disease;combined with liver and kidney dysfunction,neuropsychiatric disorders,senile dementia,mental illness,active liver disease,severe vision or hearing impairment;d.the time of intraoperative blood transfusion or single lung ventilation less than 1 hour;surgery time> 4 hours or intraoperative need for total pneumonectomy.2.Anesthesia and ventilation processes（1）Preoperative preparation and anesthesia Patients were given intramuscular injection of 0.1g phenobarbital sodium and 0.5mg penehyclidine hydrochloride 30 min before anesthesia.The model of double lumen endotracheal tube（Double-lumen tubes,DLT）can be selected according to the height and weight of the patient and the transverse diameter of the sternum and clavicle on preoperative P-A chest film.41 F double lumen endotracheal tube was selected for tracheal diameter greater than 19 mm,39F was chosen for 17 mm,37F was chosen for more than 15 mm.Venous access was established after the patients entered the operation room.Routine electrocardiogram（ECG）,oxygen saturation（Sp O₂）,heart rate（HR）,anesthesia depth monitoring（BIS）was performed.Radial artery puncture and catheterization were performed under local anesthesia for invasive blood pressure monitor and blood specimen collection.Mask ventilation to get rid of nitrogen and input oxygen for 3min.Followed by intravenous injection of midazolam 0.05 0.1mg / kg,sufentanil 0.3ug/ kg and vecuronium 0.1 mg/kg.Double lumen endotracheal（Sheridan,Mexico）was inserted under photopic vision through mouth after the patients’ consciousness disappeared,the bispectral index（BIS）droped to 50 and muscle loosed.Bronchoscopy（Fiberoptic bronchoscopy,FOB）was used to adjust the position of the end of the tube after tracheal intubation.The central venous pressure（CVP）was monitored by the right jugular vein catheterization after intubation.During the operation,continuous infusion of propofol 3 8 mg·kg-1·h-1 and remifentanil 0.2 0.4 ug·kg-1·min-1,intermittent infusion of vecuronium 0.08 mg·kg-1·h-1 to maintain anesthesia.Maintain bispectral index（BIS）value in the range of 40 to 50.（2）Ventilation process After the catheter was fixed,connect the Aestiva5/7900 anesthesia machine to the intermittent positive pressure ventilation（IPPV）.The concentration of inhaled oxygen（Fi O₂）was maintained at 100% and the oxygen flow rate was 1.5 L/min.For two lung ventilation,the tidal volume（VT）was 7 ml/kg,and the ventilation frequency was 12/min and the inspiratory-to-expiratory ratio was 1:1.5.One lung ventilation was performed at the beginning of the operation.The VT of the CV group was 6 ml/kg,and the ventilation frequency was 12/min,the inspiratory-to-expiratory ratio was 1:1.5.For contralateral lung in the LV group,the VT was 6 ml/kg,and the ventilation frequency was 12/min,and the inspiratory-to-expiratory ratio was 1:1.5;meanwhile,the ipsilateral bronchial tube was connected with the same type of anesthesia machine,the VT was 0.3⁰.5 ml/kg,and the ventilation frequency was 40/min,and the inspiratory-to-expiratory ratio was 1:1.5.During mechanical ventilation,for LV group,the ventilation can be stopped if the ventilation affects the normal operation,and the ventilation capacity can be adjusted so as not to affect the operation.If Sp O₂ <93% occurred in the course of one-lung ventilation during surgery,and ventilatory parameters needed to be adjusted,then the patient should withdraw from this study.（3）Data and specimen collection Before OLV（T0）,OLV 30 min（T₁）,OLV 60 min（T₂）and the TLV 5min（T₃）,arterial blood samples were taken for determination of Pa CO₂,Pa O₂ and the oxygenation index（Pa O₂ / Fi O₂）were calculated.After removal of the specimen,small lung tissues away from lesions were taken,HE staining was performed to probe: alveolar edema,pulmonary interstitial edema,neutrophil infiltration and alveolar congestion extent.And the lung injury score was scored according to the staining results.Results: 1.During the course of this study,5 patients（3 cases in CV group and 2 cases in LV group）had Sp O₂ <93% in one-lung ventilation and were corrected after adjusting ventilatory parameters or the position of double lumen endotracheal,the 5 cases withdrew from the study.2 patients in LV group withdrew from the study,as the affected side of the lung ventilation affect the operation and no satisfied results were obtained by ventilation adjusting.Finally,60 patients were included in this study,30 cases in CV group and 30 cases in LV group.2.There was no significant difference in OLV time,operation time,intraoperative fluid volume and urine volume in LV and CV group.3.The oxygenation index of CV group and LV group decreased firstly and then increased.The oxygenation index of CV group reached the minimum value at T₂,and the oxygenation index of LV group was the lowest at T₁.There was no significant difference in the oxygenation index between LV group and CV group（p > 0.05,t = 0.22）at T0 during OLV.At T₁,T₂ and T₃,oxygenation index of LV group was obviously higher than that of CV group,p < 0.05.4.The Pa CO₂ of the patients in CV group and LV group increased firstly and then decreased.There was no significant difference in the Pa CO₂ level between LV group and CV group at T0 and T₃（p > 0.05）;the levels of Pa CO₂ in LV group were significantly lower than those in CV group at T₁ and T₂（p <0.05）.5.The severity of pulmonary interstitial edema,alveolar edema,neutrophil infiltration and alveolar congestion were significantly lower in LV group than in CV group.The score of lung injury in LV group（2.70±0.71）was obviously lower than that in CV group （3.13±0.73）,p < 0.05.Conclusion: In patients undergoing lobectomy,the application of double-lung different tilde volume ventilation modes that is one-lung ventilation assisted ipsilateral lung ventilation with low tidal volume and high frequency can get both isolation of bilateral lung,and can decrease the risk of lung oxygenation,avoid hypoxemia and carbon dioxide retention,reduce the degree of damage caused by OLV,so as to avoid the occurrence of postoperative pulmonary complications.Although this ventilation pattern occasionally affects the surgical procedure,the operation can be completed successfully in most cases by adjusting the ventilation.In this study,only one ventilation frequency was set up in ipsilateral lung ventilation,and more ventilation frequency could be tried to observe the ventilation effect.The disadvantage of this technique is the need for two anesthesia machines and the operation is cumbersome,which needs for further research in the future.