Objective: To investigate the effects of dexmedetomidine on inflammatory response and oxidative stress in children during one lung ventilation (OLV). Methods: Children undergoing OLV from September 2019 to January 2020 were randomly divided into the control group (group C) and the dexmedetomidine group (group D

25 cases for each) according to the random number table. In group D

0. 5 μg/ kg dexmedetomidine was injected after anesthesia induction

and then continued to infuse at a rate of 0. 2 μg/ kg until the end of the surgery. Group C was treated with the same amount of saline instead of dexmedetomidine. Before OLV (T1)

30 min after OLV (T2) and after surgery (T3)

arterial blood gas analysis was performed and the concentrations of NF-kB

IL-6

IL-10

SOD and MDA were measured. Vital signs and the dosage of narcotic drugs were recorded in the two groups during designed period. Results: In two groups

PO2 was decreased and A-aDO2 and RI were increased during T2 compared with T1. PO2 was decreased in group D

and the degree of the increased A-aDO2 and RI was lower in group D than in group C (P<0. 05). Compared with T1

NF-kB

IL-6

IL-10 and MDA were increased and SOD was decreased after OLV. NF-kB

MDA and IL-6 in group D were lower than that in group C

while IL-10 and SOD were significantly higher than that in group C (P<0. 05). The amount of propofol and remifentanil in group D was less than that in group C (P<0. 05). Conclusion: Dexmedetomidine could reduce the inflammatory reaction and oxidative stress caused by single lung ventilation

at the same time

reduce the amount of intraoperative anesthesia drug.