Objective To investigate the effects of selective lobar ventilation on intrapulmonary shunt and inflammatory response in patients with pulmonary dysfunction during thoracotomy.Methods Thirty-four ASA Ⅱ or Ⅲ patients,aged 64-79 years,weighing 50-85 kg,with moderate or severe impaired pulmonary function,scheduled for esophageal cancer radical correction,were randomly divided into two groups (n =17 each):one-lung ventilation group (group A) and selective lobar ventilation group (group B).In group A,an endobronchial blocker tube was used to obstruct the bronchus principalis and practice one-lung ventilation.In group B,an endobronchial blocker tube was used to obstruct the bronchi Iobares and practice selective lobar ventilation.Blood samples were taken from the arteria radialis and the internal jugular vein for blood gas analysis and determination of plasma concentrations of tumor necrosis factor-alpha (TNF-α),interleukin-6 (IL-6) and IL-8 by enzyme linked immunosorbent assay (ELISA) before anesthesia induction (T0),30 minutes following two-lung ventilation at the lateral position (T1),60 minutes following one-lung ventilation or selective lobar ventilation (T2) and at the end of surgery (T3).Peak airway pressure (Ppeak) and plateau airway pressure (Pplat) were recorded at the same time.Results The incidence of hypoxemia was significantly lower in group B (0) than in group A (18％,P ＜ 0.05).Compared with group A,Pliat and Ppeak at T1-3,the intrapulmonary shunt rate (Qs/Qt) at T2,TNF-α,IL-6 and IL-8 concentrations at T2-3 were significantly decreased in group B (P ＜ 0.05).Conclusion Selective lobar ventilation can reduce intrapulmonary shunt and inhibit inflammatory responses to help lessen mechanical ventilation-related lung injuryduring thoracotomy in patients with pulmonary dysfunction.