Effects Of Preoperative Pulmonary Protection On Surfactant Protein A In Lung Tissue And Postoperative Complications

Purpose Surfactant protein A(SP-A)is the most abundant pulmonary surfactantassociated protein(about 50%)in lung tissue,which is mainly synthesized and secreted by alveolar type II epithelial cells(AT2)and airway clara cells.Its function is to maintain alveolar stability,anti-inflammatory sterilization and immune regulation.Under normal conditions,SP-A can prevent pulmonary injury and pulmonary infection caused by smoke,dust,soot,microbes and other risk factors to protect the lung tissue.The more SP-A expression in lung tissue,the stronger the ability to maintain intrapulmonary homeostasis and to resist inflammatory injury.Promote the expression of SP-A,the protection of lung tissue is important.Ambroxol and budesonide,which are commonly used as respiratory agents,can enhance endogenous SP-A expression.Perioperative drug management can effectively improve pulmonary function.There was a certain correlation between pulmonary function and SP-A expression in lung tissue.This study was to investigate the effect of preoperative pulmonary protection on SP-A expression and postoperative complications in non-small cell lung cancer(NSCLC)complicated with chronic obstructive pulmonary disease(COPD).Methods Sixty patients with NSCLC complicated with COPD who underwent surgical treatment in Tianjin Chest Hospital from January 2015 to June 2016 were enrolled in this study.Thirty patients were included in the control group and thirty patients in the pulmonary protection group.The control group was given routine preoperative preparation before surgery,while the pulmonary protection group was given 1 week pulmonary protection therapy on the basis of routine preoperative preparation.Pulmonary protection treatment drugs,including ambroxol,doxofylline,budesonide and ipratropium bromide.Exhaled breath condensate(EBC)was collected by the portable exhaled condensate collection device and pulmonary function was repeated after admission and before surgery.The content of SP-A in EBC was detected by enzyme-linked immunosorbent assay(ELISA).The lung tissue samples were collected rapidly during surgery and the lung tissue was collected from the lesion above 5cm.The lung tissue SP-A level was measured by Western blotting.Continue to postoperative rehabilitation treatment after surgery and record the postoperative complications.Postoperative complications were analyzed according to the Clavien-Dindo classification system.The expression of SP-A in lung tissue and the postoperative complications were compared between the two groups.Results 1.The SP-A level of the pulmonary protection group was significant higher than that of the control group(1.05±0.21 vs 0.93±0.16)(P<0.05).2.The SP-A content in the preoperative EBC of the pulmonary protection group was significantly higher than that after admission [(5.51 ± 1.48)ng/L vs(4.99 ± 1.32)ng/L](P<0.01).There was a positive correlation between SP-A in EBC and SP-A in lung tissue(r = 0.460,P<0.01).3.After pulmonary protection treatment,the preoperative pulmonary function index was significantly higher than that after admission(P<0.01).The level of SP-A in EBC in hospital admission was positively correlated with FEV1% in hospital pulmonary function(r = 0.343,P=0.007).4.There was no significant difference in the postoperative complications and Clavien-Dindo classification system between the two groups(P>0.05).There was no significant difference in the length of operation and intraoperative blood loss between the two groups(P>0.05).The average postoperative hospital stay in the pulmonary protection group was statistically significant shorter than that in the control group [(9.2 ± 3.1)d vs(11.6 ± 4.8)d](P<0.05).Conclusion 1.Preoperative pulmonary protection can increase the expression of SP-A in lung tissue.2.After pulmonary protection treatment,the level of SP-A in EBC was higher than that after admission,and the trend of SP-A in EBC was consistent with that in lung tissue.3.Preoperative pulmonary protection can improve pulmonary function and shorten postoperative hospital stay.4.Preoperative pulmonary protection does not show a statistical advantages in postoperative complications and Clavien-Dindo complications grading system.