Effect of different tidal volume on respiratory mechanics and blood gas in lung cancer patients during one lung ventilation

Objective To study the effect of different tidal volume on respiratory mechanics and blood gas in lung cancer patients with single lung ventilation. Methods 45 lung cancer patients were selected to execute radical operation, and put into double lumen endobronchial intubation after induction of anesthesia. The patients were randomly divided into three groups in the case of minute ventilation quantity invariable during intraoperative of one-lung ventilation: group A(VT = 10 mL / kg,f = 12 / min), group B(VT = 8 mL / kg,f = 15 / min) and group C(VT = 6 mL / kg,f = 20 / min). Intraoperative continuous monitoring P ET CO 2 、Ppeak、Raw and extracting the arterial bloods for blood gas analysis before OLV,30 min after OLV,1 min before the end of OLV (T1, T2, T3 ). Results Compared with T1, Ppeak and Raw at T2, T3 significantly increased during the OLV (P 0.05). Among three groups, Ppeak and Raw decreased gradually with the VT reduction during OLV , Ppeak and Raw were least in group C, and Ppeak and Raw in group A were significantly higher than those in group B , C (P 0.05). P ET CO 2 at T3 significantly increased than those at T1, T2(P 0.05), and P ET CO 2 in group C was significantly higher than those in group A , B during the OLV (P 0.05). Compared with T1, PaO 2 were decreased, while PaCO 2 showed ascendant trend after OLV. PaO 2 was significantly lower than that in group A and B (P 0.01), and PaCO 2 in group C significantly increased than that in group A and B (P 0.05). Conclusion Using the ventilation way of group B (VT= 8 mL / kg, f = 15 / min ) is more appropriate in radical operation for lung cancer with one-lung ventilation.