[Influence and significance of intermittent ventilation on lung cytokines during cardiopulmonary bypass].

Objective: To determine the influence and significance of intermittent ventilation on lung cytokines during cardiopulmonary bypass (CPB).

Methods: Thirty-six patients with rheumatic heart disease (RHD) were divided into 2 groups randomly: Treatment group (n = 18, given intermittent ventilation once every 5 minutes during CPB; control group ( n = 18), no ventilation during CPB. A brochioalveolar lavage was performed at 2 hours after the CPB. The numbers of granulocytes and the contents of IL-1, IL-6, TNF-alpha, and LDH in the brochioalveolar lavage fluids were measured, and lung PaO2/FiO2 were measured preoperatively and at 1 hour, 4 hours, and 8 hours after the CPB termination.

Results: The numbers of granulocytes and the contents of IL-1, IL-6, TNF-alpha, and LDH of the treatment group in the brochioalveolar lavage fluids were significantly lower than those of the control group (P < 0.05), and the lung PaO2/FiO2 of the treatment group at 1 hour, 4 hours, and 8 hours after the CPB termination significantly increased than those of the control group (P < 0.05). A significant decrease of lung PaO2/FiO2 occurred in both groups at 1 hour, 4 hours, and 8 hours after the CPB compared with the same group at the baseline before the CPB (P < 0.01).

Conclusion: Intermittent ventilation has protective effects on the lung injury during CPB by decreasing granulocyte adhesion and the level of lung cytokines, alleviating the lung inflammatory reaction and endothelial cell injury.