A Preliminary Study On Changes Of Pulmonary Function In High Altitude Hypoxia Acclimatization And Adaptation

Hypoxia influences human beings the most in high altitude environment.When people ascend to high altitude from sea level or from high altitude to higher places,a series of reversible and extragenetic compensative changes will be induced by hypoxia,so that the body will be competent work and living in high altitude hypoxic environment,this process is called acclimatization.One the other hand,adaptation means that human being or animal phylogeny living in high altitude obtain some genetic anatomy and biochemistry character with hereditary basis,which enables the high altitude livings to live in high altitude with high quality.It is one of the focal point and advancing front of high altitude medicine to study on high altitude hypoxia acclimatization and adaptation mechanisms.The process of high altitude hypoxia acclimatization and adaptation exhibits time dependence,and respiratory system if one of the systems that react earliest and most evident, thus pulmonary function(including ventilation function and diffusion function) is a critical factor for high altitude hypoxia acclimatization and adaptation.So far,studies have been made on pulmonary function changes in high altitude hypoxia acclimatization and adaptation, but because of the limitation of investigation methods,experimental apparatus and study objects,previous studies were confined to investigation on effects of hypoxia on ventilation function of immigrants and native residents.In fact,few systemic studies have been made on changes of pulmonary functions in high altitude hypoxia acclimatization and adaptation, particularly,as an important ingredient,little has been known about the diffusion function.In the late 20 years,pulmonary function test improved a lot,which enables us to systemically study the characters of pulmonary function in high altitude hypoxia acclimatization and adaptation.Therefore,in this study,we observed changes of pulmonary function in high altitude hypoxia acclimatization and adaptation,so as to provide experimental proofs for high altitude hypoxia acclimatization and adaptation mechanisms study.The studies are as follows:1.Changes of pulmonary function before and after ascending to high altitude of healthy sea level Han were trailed,pulmonary function evaluation index system was screened,and the relationship of pulmonary function and acute mountain sickness(AMS) was analyzed.2.Changes of pulmonary function of high altitude pulmonary edema(HAPE) patients were investigated and compared with sea level healthy Han and healthy Han rapidly ascending to high altitude.3.Pulmonary functions of high altitude native male Tibetan were detected and compared with Han rapidly ascending to high altitude,immigrant Han,high altitude Tibetan females.4.The results are as follows:forced vital capacity(FVC),alveolar ventilation(V_A),FEV1.0/FVC,peak expiratory flow (PEF),diffusing capacity of carbon monoxide(Dlco) and diffusion constant(Dlco/V_A) of healthy male seal level youth were significantly increased within 24 h after ascending to high altitude,5.PWC170 was significantly decreased after rapidly ascending to high altitude.Sea level FVC,Dlco,diffusing capacity of carbon monoxide adjusted(DlcoAdj) and V_A were significantly positively correlated with sea level PWC170,while sea level FEV_1.0/FVC was significantly negatively correlated with sea level PWC 170.Sea level V_A was positively correlated with high altitude PWC 170.1.Sea level FVC,FEV_1.0 and PEF were negatively correlated with AMS score.2.FVC,forced expiratory volume in one second(FEV_1.0),Dlco,DlcoAdj and Dlco/V_A were significantly lower of HAPE patients than of healthy Han ascending to high altitude within 24h and sea level healthy male Han.3.No significant difference was found of FEV_1.0/FVC,PEF,MVV of HAPE patients and of sea level healthy male Han.No significant difference was found of FEV_1.0/FVC and PEF with healthy Han ascending to high altitude within 24 h.4.FEV_1.0 and PEF were significantly higher of high altitude native male Tibetan than sea level healthy male Han,while no difference was found between high altitude native male Tibetan and immigrant male Han.Dlco,DlcoAdj and Dlco/V_A were significantly high of high altitude native male Tibetan than immigrant male Han and sea level male Han.No difference was found in Dlco/V_A between high altitude native male Tibetan and high altitude native female Tibetan.The conclusions are as follows:1.Resistance of peripheral airways decrease while sea level healthy male Han rapidly ascends to high altitude,which results in an enhancement of pulmonary ventilation function.2.Diffusion constant increase significantly while sea level healthy male Han rapidly ascends to high altitude,which results in an enhancement of pulmonary diffusion function.3.Diffusion function recovers slower than ventilation function in the recovery process of HAPE patients,which indicates that diffusion function can be an effective index to evaluate HAPE patient recovery condition.4.Ventilation function of high altitude native Tibetan is significantly higher than sea level Han.5.Diffusion function of high altitude native Tibetan is significantly higher than sea level Han.6.There is no sex difference in diffusion constant of high altitude native Tibetan.