自制CO2清除器在高原富氧室中的应用

高原低氧可影响到人的各个组织系统。随着海拔高度升高 ,这种影响逐渐加重。低氧引起体力、思维、判断、定向、记忆能力减退 ,甚至产生幻觉 ,使作业效率和战斗力下降 ,指挥员出现决策失误 ,战斗员体能和操作准确性降低[1] 。West[2 ] 在 3 80 0m高原的现场双盲实验表明 ,夜间小     

自制CO2清除器在高原富氧室中的应用

目的初步探讨高原富氧室内二氧化碳(CO_2)的清除问题；方法在海拔3670m建立富氧室，放置装入医用钠石衣的自制CO_2清除器，10名移居高原一年的健康青年入室内休息3小时，期间每30分钟测一次CO_2浓度，并与未放置CO_2清除器时的室内CO_2浓度相比较；结果富氧室内试验组与对照组的CO_2浓度分别为0.12±0.11和0.41±0.22，t=3.5323，P＜0.01，差异有非常显著性；结论在高原富氧室内应用钠石灰清除器简易有效。     

海拔3700m富氧室对人体通气无氧阈值的影响

目的 观察在海拔3700m建立富氧室对人体通气无氧阈值的影响。方法 10名受试者在进入富氧室前后分别坐于踏车功量计上，以60r／min连续踏车，0W为静息时对照值，每3min递增25W，踏车至力竭时停止，用O2-CO2气体测定仪分析每个负荷最后0．5min的O2和CO2，用心电图机同步记录心率,计算肺通气量(VE)、氧耗量(VO2)、二氧化碳产生量(VCO2)、呼吸商(RQ)及氧通气当量(VE／VO2)。结果 富氧室前后在功率分别达75W和100W时VE、VO2、VCO2出现明显增加，RQ出现“转折点”，VE／VO2由下降转向平稳。结论 在海拔3700m入富氧室停留后能增加入体通气无氧阈，使肺功能得到明显提高。     

高原富氧室对人体几项生理指标的影响

目的：探讨富氧室在高原军事医学中的应用价值。方法：在海拔3700m高原室内充氧,使氧浓度提高到24．0％－25．0％。10名受试者在富氧室睡眠12h,检测富氧前,富氧2h、11h及富氧后2h静息状态下和运动中的脉搏氧饱和度（SaO2）和心率。结果：入富氧室2h和11h SaO2增高,心率降低（P＜0．01）。脱离富氧后2h,SaO2已接近富氧前水平。富氧后踏车运动中平均SaO2较富氧前增高,平均心率降低（P＞0．05）。结论：富氧环境下12h对改善高原缺氧和机体能量储备有一定作用。     

高原富氧后运动对人体NO及NOS的影响

一氧化氮 (NO)介导和调节许多病理生理过程 ,包括对血管张力、血压及器官血液的调节。一氧化氮酶 (NOS)是NO生成的关键限速因子。本文在海拔 5 380m建立富氧室 ,研究富氧后运动对人体NO及NOS的影响。作者选取自平原 (海拔1 4 0 0m)进驻海拔 5 380m一个月的 1 0名 1 9岁～ 2 1岁男性汉族健康青年 ,分两批进入富氧室 ,每批 5人。富氧室容积为5 0 .5m3 ,维持室内O2 浓度为 2 7.0 %～ 2 8.0 %。受试者于晚 2 1 :30入富氧室 ,在室内休息睡眠至翌日 9:30。再于 (1 0～ 1 4 )时在室温 (1 8℃ )采受试者肘部静脉血检测NO和NOS。第 1次采血在…     

高原富氧室改善移居者脑-体作业效率过程中视网膜的动态变化

人到高原，受低氧、低气压的影响，机体生理负荷加重，脑-体作业能力显著下降，海拔越高生理负荷愈重，缺氧程度就愈明显，随着海拔的升高，人脑-体功效能力就愈低。在这样的环境中，移居者视网膜可发生以动、静脉为主的缺氧性改变，本文旨在探讨高原富氧室的建立对提高和改善人脑-体功效能力过程中视网膜动态变化。作者选择驻海拔3700m西喀喇昆仑山三十里营房6个月的某部汉族男性青年20名，均为平原出生，健康，分3批进入富氧室，室内氧含量维持在(240～250)ml／L，进入富氧室前及运动后与富氧室内活动，睡眠12h运动后10min，     

富氧室在海拔3700m对人体体力活动时氧耗量的影响

目的观察在海拔3700m建立富氧室对人体体力活动时氧耗量的影响。方法:10名受试者在进入富氧室前后分别观察氧耗量(VO2)及氧脉搏(VO2/HR)。结果:心率在100b-170b/min时,富氧室随HR增加而呈线性增加[分别为Y=(0.0165+0.0073)x,r=0.9877,P<0.001;Y=(-0.1629+0.0087)x,r=0.9902,P<0.001]。结论:富氧室在高原能提高心脏作功效率和改善肺功能。     

人工富氧环境改善急进高原人员睡眠效果的研究

Objective To study the effects of the artificial oxygen-enriched environment (is called "oxygen-enriched room" in short) on sleep efficiency of the people who participate in the mission on plateau with hurry-up entry,and to investigate the anti-hypoxia effect of oxygen-enriched room to plateau acclimatization. Methods Eighteen subjects were randomly and averagety allocated into plain group,oxygen-enriched group and hypoxia group.Only the later two groups were dispatched to plateau by air.Molecular sieve oxygenerator was used to supply the room with oxygen on 3500 m plateau.The oxygen-enriched group and hypoxia group got into the oxygen-enriched rooms and normal rooms respectively at 22 o' clock and took rest till to 9 o' clock next morning.The changes of heart rate (HR) and the saturation of blood oxygen (SaO2) of three groups were recorded and compared between the states of with and without oxygen enrichment.The subjects were monitored by sleep respiration recording and analysis system. Results ①The SaO2 of the oxygen-enriched group was 92.3%±1.0%,and it was significant higher than the state before oxygen enrichment (82.9%±4.2%) and than that of hypoxia group (79.3%±5.9%,P<0.01),but lower than that of plain group (97.3%±0.8%,P<0.05).②There were less deep sleep and more slight sleep in hypoxia group and oxygen-enriched group than in plain group.The hypopnea and apnea hypopnea index (AHI) of plain group was significant lower than that of hypoxia group and oxygen-enriched group (P<0.05).The AHI of the oxygen-enriched group was 28.1±11.9,and it was significant lower than that of hypoxia group (53.2±23.4)(P<0.05).③The normalized low-frequency (Ln) and the ratio of low-frequency to high-frequency (LF/HF) measured in sleep was respectively 89.3±2.9 and 6.4±1.4 in oxygen-enriched group comparing to 90.2±1.8 and 9.9±1.9 in hypoxia group but without statistical difference.The corresponding Ln and LF/HF of plain group was 85.8±2.9 and 6.4±1.4 respectively,significantly higher than those of other two groups (P<0.05).Plain group also showed higher normalized high-frequency than others(P<0.05). Conclusions Oxygen-enriched environment can effectively improve the sleep quality but significantly change heart rate variation (HRV) of the people who participate in the mission with hurry-up entry to plateau.Further studies are still needed to reveal the quantitative effectiveness of oxygen-enriched room to plateau acclimatization.     

富氧对海拔3700m高原人体运动心力储备的影响

目的　探讨富氧对高原人体运动心力储备方面的影响。方法　对海拔 3 70 0m高原的 1 2名健康青年富氧 (氧浓度为 2 4%～ 2 5 %)前后分别进行踏阶运动 ,采用心力监护仪采集和记录心动周期和心力信息 ,把完成规定运动量运动后第一心音 (S1 )幅值对安静时S1 幅值增加的相应倍数评估心肌收缩能力储备指数 (CCRI) ;利用舒张期和收缩期时限数据计算舒张期 /收缩期比值 (D/S比 )。结果　运动后较安静时HR ,D/S ,S1 幅值均增高 ,有非常显著性差异 (P <0 .0 1 ) ;富氧运动较未富氧运动CCRI,D/S ,S1 幅值增高 ,有显著性差异 (P <0 .0 5 ) ,HR无统计学意义 (P >0 .0 5 )。结论　高原低氧环境下心脏储备主要是心肌收缩能力储备而不是心率储备。富氧对增强机体心力储备具有重要作用     

海拔3700m富氧室对青年劳动前后血流动力学影响

目的：探讨在高原建立富氧室对青年运动前后血流动力学的影响，为提高高原劳动能力探索有效途径；方法：10名受试者在进入富氧室前后及运动前后分别坐于踏车功量机上，以60rpm连续蹬车，0W为静息时对照值，从25W开始，每3分钟递增25W，蹬车至力竭时停止，然后用XG－Ⅲ血液循环自动测试仪检测血流动力学指标；结果：富氧后运动前P、BK、PAWP、CCP、η、ALT为静息状态均降低，差别有显著性（P＜0．05或P＜0．01），SV、MAP、BV均明显增高，差别有非常显著性（P＜0．001）；富氧后运动后P、BK、TPR较静息状态均升高，差别有显著性（P＜0．05或P＜0．01），PAWP升高明显，差别有非常显著性（P＜0．001），CCP、η、ALT降低明显，差别有非常显著性（P＜0．001），其余指标无统计学意义（P＞0．05）；富氧后运动后SV、CCP、η、mAP、BV、ALT较运动前均降低，差别有显著性（P＜0．05或P＜0．01），P、BK、TPR、PAWP均升高明显，差别有非常显著性（P＜0．001）；结论：高原富氧室可改善劳动者缺氧，增强心功能，提高劳动效率，是一种较理想的高原供氧途径。     

高原冲击伤的损伤特点研究

目的：探讨高原冲击伤的损伤特点。方法：大鼠分别暴露于环境压力53.99kpx,61.33kpa和96.60kpa，然后用BST-I型生物激波管致伤，冲击波超压峰值为190.40kpa，正压持续时间为10ms.结果:随环境气压降低,冲击波所引起的大鼠死亡率明显增加,肺损伤程度明显加重,伤后6h,53.99kpa,61.33kpa和96.60kpa暴露组的死亡率分别为35.0%,25.0%和0%,肺出血和肺水肿的程度随环境压降低而明显加重,平均肺体脂数分别为1.49%,1.31%和0.93%.结论:环境气压降低可降代动物对冲击波的耐受性，高原冲击伤的死亡率和肺损伤程度较海平面和低海拔地区更高。     

Energy at high altitude

For the military doctor, an understanding of the metabolic effects of high altitude (HA) exposure is highly relevant. This review examines the acute metabolic challenge and subsequent changes in nutritional homeostasis that occur when troops deploy rapidly to HA. Key factors that impact on metabolism include the hypoxic-hypobaric environment, physical exercise and diet. Expected metabolic changes include augmentation of basal metabolic rate (BMR), decreased availability of oxygen in peripheral metabolic tissues, reduction in VO2 max, increased glucose dependency and lactate accumulation during exercise. The metabolic demands of exercise at HA are crucial. Equivalent activity requires greater effort and more energy than it does at sea level. Soldiers working at HA show high energy expenditure and this may exceed energy intake significantly. Energy intake at HA is affected adversely by reduced availability, reduced appetite and changes in endocrine parameters. Energy imbalance and loss of body water result in weight loss, which is extremely common at HA. Loss of fat predominates over loss of fat-free mass. This state resembles starvation and the preferential primary fuel source shifts from carbohydrate towards fat, reducing performance efficiency. However, these adverse effects can be mitigated by increasing energy intake in association with a high carbohydrate ration. Commanders must ensure that individuals are motivated, educated, strongly encouraged and empowered to meet their energy needs in order to maximise mission-effectiveness.     

Sleep at high altitude

New arrivals to altitude commonly experience poor-quality sleep. These complaints are associated with increased fragmentation of sleep by frequent brief arousals, which are in turn linked to periodic breathing. Changes in sleep architecture include a shift toward lighter sleep stages, with marked decrements in slow-wave sleep and with variable decreases in rapid eye movement (REM) sleep. Respiratory periodicity at altitude reflects alternating respiratory stimulation by hypoxia and subsequent inhibition by hyperventilation-induced hypocapnia. Increased hypoxic ventilatory responsiveness and loss of regularization of breathing during sleep contribute to the occurrence of periodicity. Interventions that improve sleep quality at high altitude include acetazolamide and benzodiazepines.     

Delirium at high altitude

A 35-year-old man on a trek to the Mount Everest region of Nepal presented with a sudden, acute confusional state at an altitude of about 5000 m. Although described at higher altitudes, delirium presenting alone has not been documented at 5000 m or at lower high altitudes. The differential diagnosis which includes acute mountain sickness and high altitude cerebral edema is discussed. Finally, the importance of travelling with a reliable partner and using proper insurance is emphasized in treks to the Himalayas.     

氧烛对高原人体血氧饱和度及血乳酸的影响

目的观察在高原利用氧烛建立富氧室对移居高原男青年血氧饱和度（SaO2）及血乳酸（BLA）的影响。方法 8名进驻高原1年的受试者在海拔3700 m夜间睡眠,监测其常氧和富氧（氧浓度为24%～25%）条件下的SaO2变化;起床脱离富氧室3 h后空腹采集肘静脉血,检测BLA在富氧前、富氧后的变化。结果富氧较常氧下受试者SaO2增高（P〈0.01）,富氧组BLA与常氧组比较降低（P〈0.01）。结论用氧烛制作富氧室可显著改善人体高原缺氧状态。     

高原军人睡眠状况调查

目的研究探讨高原军人睡眠质量状况。方法采用匹兹堡睡眠质量指数量表(PSQI)分别对驻守在海拔3700m的103名和海拔4300m的105名军人进行问卷调查并进行统计学处理。结果海拔越高,PSQI总分和各因子得分越高(P<0.05或P<0.01),睡眠质量越差,主要表现为,主观睡眠质量差、入睡时间延长、睡眠效率下降、睡眠障碍增多和日间功能障碍等。结论高原低氧环境军人睡眠质量下降,有必要采取一定的干预措施。     

Ketamine anesthesia at high altitude

There is a clinical need for a safe and effective anesthetic technique in high altitude and remote areas. This report presents a series of 11 consecutive cases documenting the use of ketamine anesthesia in a remote hospital at an altitude of 3,900 m, by primary-care physicians without specialist training in anesthesia. The method of administration is fully described. At a low dose of 2.0 mg/kg, ketamine produces a dissociative anesthesia that does not depress the hypoxic drive, or interfere with the pharyngeal or laryngeal reflexes. Although supplemental oxygen is useful in the recovery phase for less acclimatized individuals, it is usually not required as reductions in oxygen saturation can be raised by physical stimulation that encourages the patient to breathe faster and deeper. The common side effect of emergent nightmares was avoided using midazolam as premedication and a quiet recovery area. This study offers the first available evidence that ketamine with midazolam offers a safe and effective means of anaesthesia at very high altitude, without the need for specialist equipment or training, by careful clinicians experienced in basic airway management.