Objective To compare the effects of oxygen therapy and local pressurization in alleviating plateau hypoxia at high altitude.Methods Forty-five healthy male soldiers were investigated at an altitude of 3992 meters.The subjects were randomly divided into three groups, ie.an oxygen inhalation group, a single-soldier oxygen increasing respirator (SOIR) group and a BiPAP group.The oxygen inhalation group was treated with oxygen inhalation via nasal catheter at 2 L/min.SOIR was used to assist breath in the SOIR group.The BiPAP group were treated with bi-level positive airway pressure ventilation, with IPAP of 10 cm H20 and EPAP of 4 cm H2O.PaO2、PaCO2、SpO2 and heart rate were measured before and 30 minutes after the treatment.Results There were continuous increase of PaO2 from (53.30±4.88) mm Hg to (58.58±5.05) mm Hg and (54.43±3.01) mm Hg to (91.36±10.99) mm Hg after BiPAP ventilation and oxygen inhalation, respectively (both P < 0.01).However, the PaO2、of the SOIR group was decreased from (56.00±5.75) mm Hg to (50.82±5.40) mm Hg (P < 0.05).In the other hand, the PaCO2、 was increased from (30.41±1.51) mm Hg to (32.5±2.98) mm Hg in the oxygen inhalation group (P< 0.05), declined from (28.74±2.91) mm Hg to (25.82±4.35) mm Hg in the BiPAP group (P < 0.05), and didn't change significantly from (28.65±2.78)mm Hg to (29.75±3.89) nun Hg in the SOIR group (P > 0.05).Conclusions Both BiPAP ventilation and oxygen inhalation can alleviate plateau hypoxia by improving PaO2 at 3992 meter altitude while SOIR has no significant effect.

Objective To explore the clinical efficacy of video-assisted thoracoscopic intrathoracic fixation in the treatment of multiple rib fractures.Methods Clinical data of 93 cases of multiple rib fractures in our department from August 2019 to April 2022 were retrospectively compared.They were divided into thoracoscopic group(n=50)and traditional group(n=43)according to surgical methods.In the thoracoscopic group,the memory alloy rib plate was used for thoracoscopic intrathoracic fixation,and in the traditional group,the memory alloy rib plate was used for traditional thoracotomy to treat multiple rib fractures.The operation time,intraoperative blood loss,postoperative hospital stay,postoperative catheter duration,postoperative pain time,postoperative drainage volume,and postoperative complications were compared between the two groups.Results As compared with the traditional group,the thoracoscopic group had significantly shorter operation time[(96.1±24.7)min vs.(110.2±29.1)min,t=-2.526,P=0.013],less intraoperative blood loss[(76.0±38.4)ml vs.(140.2±80.8)ml,t=-4.767,P=0.000],shorter postoperative catheter duration[(3.9±1.6)d vs.(6.2±1.8)d,t=-2.739,P=0.008],less postoperative drainage volume[(132.4±53.9)ml vs.(157.9±50.5)ml,t=-2.345,P=0.021],shorter postoperative hospital stay[(5.8±2.5)d vs.(9.7±2.5)d,t=-4.397,P=0.000],and shorter pain time[(4.9±1.2)d vs.(5.8±1.4)d,t=-2.199,P=0.030].The incidence of postoperative pneumonia,atelectasis,and pleural effusion in the thoracoscopic group was significantly lower than that in the traditional group(P<0.05).Follow-ups at 1,3,and 12 months after surgery showed that the rib plate was firmly fixed without any displacement,deformation,or detachment.Conclusion Video-assisted thoracoscopic intrathoracic fixation in the treatment of multiple rib fractures has advantages of less trauma,less pain,faster recovery,and definite clinical results,which is worthy of clinical application and promotion.