Abstract:Objective To evaluate the effect of Dexmedetomidine on the lung compliance (Cdyn) and the expressions of Toll-like receptors 2 and 4 (TLR2 and TLR4) in the peripheral blood during perioperative period in the patients undergoing laproscopic colorectal cancer radical resection. Methods Twenty patients aged 33 to 68 years who underwent elective colorectal cancer radical resection under general anesthesia with ASA grade I or II and body mass index (BMI) <30 kg/m2 were enrolled. They were randomly divided into control group (group C) and Dexmedetomidine group (group D) with 10 in each group. In the group D, Dexmedetomidine was infused at a rate of 0.4 μg/(kg?h) from the beginning of surgery till 30 min before the end of surgery. The patients in the group C were given the same manipulation as in the group D except replacement of Dexmedetomidine by normal saline. The mean arterial pressure (MAP) and heart rate (HR) were recorded before anesthesia induction (T0), 30 min (T2), 60 min (T3) and 90 min (T4) after the beginning of surgery, at the time of extubation (T6), and 3 min after extubation (T7).Airway pressure (Paw) and Cdyn were recorded at 5 min after intubation (T1), T2-4, 30 min before the end of surgery(T5), T6 and T7, respectively. Venous blood was drawn to analyze the TLR2, TLR4 and TNF-α concentrations at T0,T4, T7 and the day after operation (T8), respectively. Results Compared with the group C, the dosage of Remifentanil in the group D was significantly decreased (P < 0.05). Compared with the group C, MAP and HR were decreased in the group D at T7 (P < 0.05); Cdyn increased in the group D at T3 and T4 (P < 0.05); serum TLR2 and TLR4 concentrations decreased in the group D at T4, T7 and T8 (P < 0.05); serum TNF-α concentration also decreased in the group D at T4, T7 and T8 (P < 0.05). Conclusions Continuous infusion of 0.4 μg/(kg?h) of Dexmedetomidine can help to maintain the hemodynamic stability, alleviate symptoms of inflammatory response induced by stress, so as to keep the vital signs stable during operation and has certain protective effect on patients.