The Clinical Research About Protective Effect Of Hypoxic Preconditioning And Postconditioning For One-lung Ventilation Associated Lung Injury

Objective To build a repeated hypoxic preconditioning and postconditioning models in vivo, and research protective effect of the models for one-lung ventilation associated lung injury in the thoracic surgery by monitoring the serum inflammatory factor and oxidative stress index at the different time points during and after the operation, which is to provide a kind of new clinical ways and thinking for reducing the perioperative acute lung injury.Methods1)80patients, who would be undergoing operatien (pulmonary lobectomy+mediastinal lymph node dissection), were collected form June in2011to March in2012. The patients were divided to four groups randomly and20cases were in each group, which were control group, preconditioning group, postconditioning group and preconditionging combined with postconditioning group.2)There is no any intervention for control group. For hypoxia preconditioning group, intermittent one-lung ventilation is done for20minutes after tracheal cannula. For hypoxia postconditioning group, intermittent two lung ventilation is done for30minuters after sugery. Combined treatment group means hypoxia postconditioning is done based on the hypoxia preconditioning.3) The blood sample of all patients were collected during and after the operations at the three different times, which were before tracheal intubation (T1), before the lobectomy(T2), and two hours after operation(T3). A part of blood sample was sent to test the blood routine which was used to test the percentage of polymorphonuclear cells (PMN). The rest sample were centrifugated and the serum were saved and uesd to test the inflammatory cytokines interleukin-6(IL-6) and oxidation stress index, such as Superoxide Dismutase (SOD) and Malondialdehyde (MDA), with the method of enzyme-linked immunosorbent assay (ELISA).4) The all experimental results were analyzed with the SPSS17.0software and p values less than0.05indicated the difference is significant.Results1) The basic information of groups80cases were divided into four groups randomly, and sex ratio, mean age and the operative time were all no significant difference.2) Control group Comparing with the time point T1before surgery, IL-6, MDA and PMN incread significantly while SOD decreased significantly. Comparing with the time point T2during the surgery, IL-6and MDA incread significantly and SOD decreased significantly, but there was no significant difference about PMN. 3) Hypoxia preconditioning group Comparing with the time point T1before surgery, IL-6, MDA and PMN incread significantly while SOD decreased significantly. Comparing with the time point T2during the surgery, the indexes of IL-6, MDA and PMN incread significantly while SOD decreased significantly. Comparing with the control group, IL-6, MDA and PMN incread significantly while SOD decreased significantly during the surgery(T2), but the results were no different significant after surgery (T3).4) Hypoxia postconditioning group Comparing with the time point T1before surgery, IL-6, MDA and PMN incread significantly while SOD decreased significantly. Comparing with the time point T2during the surgery, IL-6and MDA incread significantly and SOD decreased significantly, but there was no significant difference about PMN. Comparing with the control group, the results all were not different significantly during and after surgery, but we can see IL-6and MDA all decreased and SOD increased after surgery(T3). Comparing with the hypoxic preconditioning group, IL-6, MDA and PMN incread significantly while SOD decreased significantly during the surgery(T2), however, the results were no significant difference after surgery(T3).5) Hypoxia preconditioning+Hypoxia postconditioning group Comparing with the time point T1before surgery, IL-6, MDA and PMN incread significantly while SOD decreased significantly. Comparing with the time point T2during the surgery, IL-6and MDA incread significantly and SOD decreased significantly, but there was no significant difference about PMN. Comparing with the control group, IL-6, MDA and PMN incread significantly while SOD decreased significantly during and after surgery. Comparing with the hypoxic preconditioning group, all results were no different before and during the surgery. Comparing with the hypoxic postconditioning group, IL-6, MDA and PMN incread significantly while SOD decreased significantly before and during the surgery(at T1and T2points).Conclusion1) Repetitive hypoxic preconditioning in vivo for20minutes before thoracic surgery can alleviate the inflammatory reaction and oxidative stress.3) Repetitive hypoxic preconditioning in vivo for20minutes before the thoracic surgery combined with repetitive hypoxic postconditioning in vivo for30minutes after surgery can alleviate the inflammatory reaction and oxidative stress significantly.