高原不同海拔暴露对肺通气功能及代偿能力的影响

目的探讨急性暴露不同海拔的平原人群肺通气功能的变化情况以及潜在的机制。方法从急进高原的某部官兵中筛选出100例未出现急性高原病的受试者,对其在平原(300 m)、海拔3 700 m和4 100 m的高原地区分别进行肺通气功能检测、6 min步行试验和采集空腹血,利用ELISA检测血浆低氧诱导因子-1α(HIF-1α)和内皮素-1(ET-1)的水平,连续监测法检测血浆血管紧张素转换酶(ACE)的活性。对不同海拔高度受试者用力肺活量(FVC)和6 min行走距离进行相关性分析。结果海拔3 700 m和4 200 m时受试者的FVC、6 min行走的距离显著低于在平原时(P0.05),并且在4 200 m时受试者的FVC和6 min行走的距离较在3 700 m也显著降低(P0.05);在4 200 m时受试者的FEV1、6 min步行试验后呼吸频显著高于在平原(300 m)时(P0.05)。受试者在海拔300 m和3 700 m之间以及在海拔300 m和4 200 m之间FVC的改变量和6 min行走距离的该变量呈正相关。海拔3 700 m和4 200 m时受试者的ET-1显著高于在平原(300 m)时(P0.05),并且在4 200 m时受试者的血浆ET-1水平较在3 700 m也显著升高(P0.05);在4 200 m和3 700 m时受试者的HIF-1α水平和ACE活性著高于在平原(300 m)时(P0.05)。结论急性暴露高海拔的环境使肺通气功能下降,并伴随心肺代偿能力的下降,其可能是由于肺间质少量的液体储留所致。

Study on pulmonary ventilation function and it's compensation in different high altitude

Objective To study the change of pulmonary ventilation function of plainsman in different high altitude and potential mechanism.Method One hundreds subjects was rapidly elevated to high altitude 3 700 m and then 4 200 m from sea level (300 m).They had not suffered with acute mountain illness.The pulmonary ventilation function and 6 minute walking test (6MWT) of subjects were evaluated and their fasting blood samples had been collected in different altitudes.The plasma hypoxia inducible factor-1α(HIF-1α) and endothelin-1(ET-1) levels were detected by ELISA,and the activity of plasma angiotensin converting enzyme (ACE) had been measured by continuous monitoring method.The correlation of the change of forced vital capacity(FVC) and 6 min walk distance(6MWD) among different altitude was analyzed by Pearson analysis.Result The FVC and 6MWD of subjects in 3 700 m and 4 200 m were significant decreased,compared with in sea levels (P＜0.05).And the FVC and 6MWD of subjects in 4 200 m was lower than in 3 700 m (P＜0.05).The FEV1 and respiratory rate was high in 4 200 m than in 300 m (P＜0.05).The change of FVC and 6MWD between 300 m and 3 700 m or 4 200 m was notable positive correlation (P＜0.05).Compared to plasma ET-1 levels of subjects in sea levels,they were elevated in 3 700 m and 4 200 m (P＜0.05) and the levels of ET-1 were higher in 4 200 m than in 3 700 m (P＜0.05).The levels of plasma HIF-1α and activity of ACE of subjects was significant higher in 4 200 m and 3 700 m than in sea levels (P＜0.05).Conclusions Pulmonary ventilation function and it's compensation descend when subjects rapidly expose at high altitude,which might due to a small amount of pulmonary interstitial fluid retention.