To investigate the effects of intravenous pumping of lidocaine combined with dexmedetomidine (Dex) on the lung function and immune function of the patients undergoing thoracoscopic surgery.

A total of 50 patients (ASA Ⅰ-Ⅱ grade, 31 males and 19 females) undergoing thoracoscopic surgery with unilateral pulmonary lesions and intrabronchial anesthesia in the Department of Thoracic Surgery of Pizhou People′s Hospital of Jiangsu Province from July 2016 to July 2018 were selected for this study. The patients were randomly divided into a control group (n=24) and a study group (n=26). In the control group, continuous intravenous pumping of Dex 0.5 μg/kg was given in 15 minutes before anesthesia induction, and then 0.25 μg/kg·h was continuously pumped until the thoracic incision was closed. In the study group, continuous intravenous pumping of lidocaine 1 mg/kg was given in 15 minutes before anesthesia induction, and then lidocaine 1 mg/kg·h was continuously pumped until the thoracic incision was closed. The oxygenation index (OI), intrapulmonary shunt rate () and respiratory index (RI) were compared at one-lung ventilation (T₁), at the end of one-lung ventilation (T₂) and before returning to the ward (T₃) between the two groups. CD4⁺ , CD8⁺ and CD4⁺ /CD8⁺ were recorded before anesthesia induction (T₄), after operation (T₅) and at postoperative 24 hours (T₆) in the two groups.

No significant difference was found in the OI, and RI at T₁ between the two groups (P>0.05). At T₂ and T₃, the values of OI in the study group [(363.48±24.11) mmHg and (388.84±34.64) mmHg, respectively] were significantly higher than those of the control group [(335.48±31.11) mmHg and (360.88±38.42) mmHg, respectively, P<0.05], the values of in the study group [(14.86±2.58)% and (12.56±2.28)%, respectively] were significantly lower than those of the control group [(18.33±2.53)% and (15.57±1.90)%, respectively, P<0.05], and the values of RI in the study group [(0.82±0.18) and (0.52±0.12), respectively] were significantly lower than those of the control group [(1.07±0.14) and (0.78±0.13), respectively, P<0.05]. There was no significant difference in CD4⁺ , CD8⁺ and CD4⁺ /CD8⁺ at T₄ between the two groups (P>0.05). At T₅ and T₆, there was no significant difference in CD8⁺ between the two groups (P>0.05), however, the values of CD4⁺ in the study group [(36.16±7.84)% and (39.72±8.79)%, respectively] were significantly higher than those of the control group [(29.48±8.10)% and (32.48±8.87)%, respectively, P<0.05], and the values of CD4⁺ /CD8⁺ in the study group [(2.12±0.20) and (2.13±0.19), respectively] were significantly higher than those of the control group [(2.00±0.20) and (2.01±0.17), respectively, P<0.05)].

Intravenous pumping of lidocaine combined with Dex could increase the OI, decrease the () and RI, increase the CD4⁺ and CD4⁺ /CD8⁺ , and improve the lung function and immune function of the patients undergoing thoracoscopic surgery.