离心机模拟空战机动训练时飞行员的心律变化

目的 研究高性能战斗机飞行员进行模拟空战机动(SACM)训练时心血管功能变化情况，从而提出保护措施。方法 高性能战斗机飞行员10名，在载人离心机上进行SACM训练。训练中，飞行员穿用抗荷服，做L-1抗荷动作及进行抗荷正压呼吸(PBG)；监视并记录心电图、耳脉搏和呼吸。结果 10名飞行员在SACM时均发生不同程度的心律失常。心律失常以室性期前收缩为主，多发生于吸气末，4G以上的高G暴露中开始有心律失常发生，9G时发生率最高。心率增快程度和 Gz值呈正相关。在抗荷动作的吸气相，耳脉搏的幅值突然降低。结论 SACM训练中，室性期前收缩多发，这可能为一种潜在性的危险。应训练飞行员正确掌握抗荷动作和PBG的实施要领，调控有氧体育锻炼强度，定期进行SACM训练，并实行心电图监控，以减少空战机动中心律失常发生率。     

94例健康航海人员24小时动态血压监测

目的　探讨健康航海人员 2 4h动态血压监测 (ABPM)各参数的正常值。方法　用标准水银柱式血压计测量左上臂坐位血压 ,对 94名血压 <140 / 90 mm Hg的健康航海人员 ,行 2 4h ABPM。结果　 94名健康航海人员 ABPM各参数均值 (上限值 )分别为 :2 4h动态血压 116 .10 (12 7.8) / 74.36(83.6 ) mm Hg,白天血压 119.13(131.6 ) / 76 .82 (86 .0 ) mm Hg,夜间血压 10 5 .5 1(119.9) / 6 5 .97(77.8)mm Hg。≥ 35岁组 2 4h平均舒张压高于 <35岁组 (P<0 .0 1)。不同海域的航海人员 2 4h ABPM各相应参数均值无明显差别 (P均 >0 .0 5 )。结论　建议以 2 4h动态血压均值 <12 8/ 84mm Hg,白天均值 <132 / 86 m m Hg,夜间均值 <12 0 / 78mm Hg,夜间血压下降率≥ 10 %和血压负荷值 <15 %作为暂定健康航海人员 2 4h动态血压正常参考值标准。     

Psychiatric disorders in civilian pilots

Psychiatric disorders are second only to cardiovascular disorders as a cause of permanent loss of licence in both professional aircrew and private pilots in the UK. In professional aircrew, psychiatric disorders are commonly aviation-related, whilst in private pilots less effective selection and the stresses of business and personal affairs are common factors. Because human error is a major cause of accidents, the early diagnosis of disorders of thought and behaviour is clearly crucial in promoting flight safety. Airline doctors and AMEs must play the most important part.     

中国军事飞行员心电图正常值研究

目的 研究确定出中国飞行员心电图正常值范围，为飞行员选拔和心血管功能专项医学鉴定提供依据。方法 采用十二导联同步心电图仪采集1098名飞行员(其中男飞行员1043名，女飞行员55名)心电图，然后进行测量与统计分析。结果 得出了不同年龄(20～55岁)、不同机种的1043名男飞行员和55名女飞行员十二导联同步心电图有关指标的正常值范围(包括：心率、心电轴、P-R间期、QT间期、QRS波振幅、QRS波时限、P波振幅、T波振幅等)；几个主要发现是：飞行人员心率变化范围大(40～100次／rain)，≤60次／min约占25％；心电轴轻度左偏和右偏分别占3．5％(男性)、1．8％(女性)和6．2％(男性)、3．6％(女性)；P波振幅、时限均以I导联最大；QRS波时限、QT间期以V2、V3导联最大，aVL最小；R波振幅、T波振幅以V3、V4最明显；在导联之间，PR间期离散度最小(男≤11ms、女≤12ms)，而QT间期离散度最大(男≥24ms、女≥40ms)。结论 采用十二导联同步心电图采集记录方法研究确定中国飞行人员心电图正常值范围是准确可靠的，可为飞行员选拔和心血管功能专项医学鉴定提供重要依据。     

健康飞行员心脏超声检查结果的分析

有资料表明 ,无症状中度心功能不全在一般人群中发生率为 2 .8% [1 ] ,故目前临床上越来越重视无症状心功能不全的存在。保障飞行人员的身体健康是我们医务人员的重要责任 ,飞行人员这一特殊人群的心脏超声结果应如何认识 ?常规大体检是否应增加心脏超声检查 ?同同道们商榷。一、对象与方法1.对象 :飞行人员组 :5 5名飞行人员 ,年龄 2 5～ 4 8岁 ,平均 34.3岁 ,飞行机种为歼 - 6、歼 - 7,歼 - 8和运 - 5 ,飞行时间 70 0～ 310 0 h。当年飞行健康体检均为合格。正常地面人员组 :6 0名 ,年龄 2 4～ 5 1岁 ,平均年龄 35 .7岁 ,均无心血管病史。…     

老年人胃24 h pH监测分析

目的为获得老年人胃内酸的数据并与其他人群进行对照比较,以了解老年人胃酸的特点及其与酸相关疾病的临床意义。方法采用便携式24hpH动态监测仪对23例老年人进行胃24h pH监测,并与29例其他人群进行对照比较。以pH<1、pH<2和pH<3的总时间%、平均pH、中位pH为观察指标。结果老年人组胃24h pH指标中的中位pH明显高于对照组(P<0.05),pH<1的总时间%明显低于对照组(P<0.05),平均pH也高于对照组、pH<2和pH<3的总时间%指标也低于对照组,但统计学无显著差异性(P>0.05)。结论胃24hpH监测显示老年人与其他人群比较,胃内酸度降低,特别是强酸所占的时间减少,可能与老年人壁细胞分泌功能较年轻人减弱有关。提示虽然老年人酸相关疾病发病率增高,胃酸可能不是主要的致病因素。     

Improving diagnostic accuracy of MDCT coronary angiography in patients with mild heart rhythm irregularities using ECG editing

OBJECTIVE: The objective of our study was to compare diagnostic accuracy of MDCT coronary angiography in a population of patients with mild heart rhythm irregularities before and after editing the ECG. SUBJECTS AND METHODS: Thirty-eight patients who underwent MDCT coronary angiography and conventional coronary angiography were enrolled in the study. The inclusion criterion was the presence of mild heart rhythm irregularities (i.e., premature beats; atrial fibrillation; mistriggering; or low heart rate, defined as 40 beats per minute or less) during the scan. All patients underwent MDCT with the following parameters: 16 detectors; collimation, 0.75 mm; gantry rotation time, 375 msec; 120 kV; and effective milliampere-second setting, 500-600. Images were reconstructed in two settings: before ECG editing and after ECG editing (i.e., arbitrary modification of temporal windows within the cardiac cycle at the site of mild heart rhythm irregularities). Data sets were scored for the presence of significant stenoses (> or = 50% lumen reduction) in coronary segments > or = 2 mm diameter. The results of the two groups were compared with a McNemar test, and a p value of less than 0.05 was considered significant. RESULTS: The sensitivity, specificity, and negative and positive predictive values of MDCT coronary angiography for the detection of significant stenoses before and after ECG editing were 63% (41/65) and 92% (78/85); 97% (251/260) and 96% (305/317); 87% (62/71) and 87% (81/93); 91% (251/275) and 97% (305/313), respectively (p < 0.05). The proportion of nonassessable segments was reduced from 17% (70/416) before ECG editing to 2% (10/416) after. CONCLUSION: ECG editing significantly improves diagnostic accuracy in a selected population of patients with mild heart rate irregularities.     

老年人食管24 h pH监测分析

目的探讨老年人食管酸暴露情况并与其他人群进行对照比较,以了解老年人食管酸反流的特点及其临床意义。方法采用便携式24 h pH动态监测仪对31例老年人进行食管24 h pH监测,并与40例其他人群进行对照比较。结果老年人组24 h食管酸暴露的6项pH指标中有4项与对照组差异有统计学意义(P<0.05)。95%分布范围中,立位pH<4的总时间(%)和pH<4的反流次数的指标两组较为接近,余4项指标老年组数值均高于对照组。总计分老年组为14.9,高于对照组(12.7)。结论老年人组食管酸暴露多项指标高于对照组,提示可能与老年人食管运动功能和清除酸的能力下降以及食管下端括约肌(LES)功能较年轻人减弱有关。     

食管测压和24h食管pH值监测用于食管源性胸痛32例分析

目的总结分析食管测压、24 h食管pH值监测对食管源性胸痛的诊断价值。方法对58例经临床及心血管检查明确为非心脏起因的发作性胸痛患者进行食管测压、24 h食管腔内pH监测检查。结果 58例中,有32例（55.17%）诊断为食管源性胸痛,其中18例（56.25%）符合胃食管反流病（有6例合并食管运动异常）,15例（46.87%）为非特异性食管运动障碍,3例（9.38%）为贲门失弛缓症,1例（3.13%）为胡桃夹食管,1例（3.13%）为弥漫性食管痉挛。结论食管运动障碍所致胸痛以胃食管反流病引起的最多,其临床表现与心源性胸痛相似,有时仅从症状上难以鉴别,食管测压、24 h食管pH监测对发现食管源性胸痛有重要意义。     

Radiological demonstration of gastroesophageal reflux. Diagnostic value of barium and bread studies compared with 24-hour pH monitoring

PURPOSE: To correlate gastroesophageal reflux (GER), demonstrated by a radiological method using food, with the reflux events, as determined by 24-h pH monitoring. MATERIAL AND METHODS: One hundred and seventeen patients with a median age of 47 years (86 male and 31 female) were examined. In the supine left position, the patient consumed 360 ml of barium contrast. Fluoroscopy was performed with the patient in the supine right oblique position during mastication and swallowing a piece of rye bread with liver pate and barium. The test was positive if barium was observed > or =5 cm proximal to the gastroesophageal junction. An antimony pH-probe was placed 5 cm above the lower esophageal sphincter, previously determined by manometry. The position was controlled by radiography after positioning and before removal. The total time of esophageal pH<4 exceeding 5.0% was considered pathological. RESULTS: The radiological method had a specificity of 100% and a sensitivity of 52% compared to 24-h pH monitoring. CONCLUSION: The high specificity of this radiological method justify direct therapeutic consequence of a positive test. However, a negative test still renders the problem unsolved.     

Heart rate monitoring of pilots during steep-gradient approaches.

As part of a large scale investigation into noise abatement landing approaches, one trial involved the flight evaluation of steep-gradient and two-segment approaches; these were 3 degress, 6 degrees, 7.5 degrees, and 9 degrees single-segment, and 7.5 degrees/3 degrees two-segment approaches. To augment the subjective opinions of the test pilots, their heart rates were monitored during all the experimental runs. The resulting heart rate values for the different approaches correlated reasonably well with the subjective ratings of the relative workload levels. There is some evidence that the pilot workload level for the 7.5 degrees/3 degrees approaches is of the same order as the level for the conventional 3 degrees gradient.     

Circadian rhythm of plasma levels of lipids, carbohydrates and various hormones in healthy pilots

Circadian variations of plasma lipids (cholesterol, total lipids, triglycerides, beta-lipoproteins), sugars and selected hormones (cortisol, testosterone, estradiol, aldosterone) were measured in 30 healthy pilots, aged 30-39 years. The control group consisted of 15 healthy nonpilots of similar age. Experimental data were statistically treated using cosinor analysis. In contrast to the ground-based personnel, the pilots showed in increase in the average daily content of lipids and hormones, a decrease in the average daily content of sugar, and an increase in the amplitude of cholesterol, triglycerides, total lipids, beta-lipoproteins, cortisol, testosterone and aldosterone. Estradiol rhythms were very similar in both groups. Acrophases of triglycerides, testosterone and estradiol were almost synchronized. Acrophases of other parameters were different in values which were greater than the acrophase drift range. The specific features of circadian rhythms of plasma lipids, carbohydrates and hormones seem to reflect the specific features of professional activities of pilots. The above investigations of circadian variations of plasma lipids, carbohydrates and hormones in healthy pilots represent the first attempt of recording circadian parameters of their biochemical substrates.     

Differentiation of malignant and degenerative bone lesions using dexamethasone interventional 3- and 24-hour bone scintigraphy

Seventy-seven adult patients with suspected skeletal metastases were divided into two groups. In group A (n=30), following intravenous administration of 20 mCi (740 MBq) of technetium-99m methylene diphosphonate (^99mTc-MDP), 3- and 24-h scintigraphy of bone lesions was performed. The 24/3 h lesion to bone background radiouptake ratio (RUR) was calculated for each lesion. In group B (n=47), the same procedure was followed with dexamethasone intervention (10 mg in 24 h) following the 3-h acquisition. In group A, after determination of the critical point, malignant and degenerative bone lesions could be separated with a sensitivity, specificity and accuracy of 0.76, 0.72 and 0.73, respectively. The mean RUR of the malignant lesions was 1.20± 0.23, and that of the benign lesions, 0.95± 0.15. In group B cases, significantly increased sensitivity, specificity and accuracy of 0.87, 0.94 and 0.92, respectively, were found (P<0.001). The mean RUR of the malignant lesions was 1.48± 0.34, and that of degenerative lesions, 0.88± 0.19. Dexamethasone interventional bone scintigraphy seems to be a new cost-effective method for differentiating malignant from degenerative bone lesions using the RUR. Correspondence to: A. Bhatnagar     

The value of 24-hour images after rest thallium injection

Rest (201) Tl imaging has been used for detecting viability, but the ideal timing for imaging after injection to maximally estimate viability is not well established. Thirty patients with fixed or incompletely reversible defects on 4 h redistribution SPECT imaging after thallium rest injection underwent 24 h imaging. Global redistribution was subjectively rated none, minimal or meaningful by two experienced observers. Fourteen patients had no meaningful redistribution at either 4 h or 24 h. Ten patients had meaningful redistribution at 4 h only. Six patients had no meaningful redistribution at 4 h but did at 24 h. Defect size was quantified using a 70% threshold. For the total group, defect size was smaller at 4 h compared to immediate imaging (38+/-18% vs 41+/-19%, P=0.06) and smaller still at 24 h (36+/-16% vs 38+/-18%, P=0.02). Later (24 h) redistribution images detected additional redistribution in 30% of the patients who did not have meaningful redistribution on early (4 h) images, and in 8% of the segments which were abnormal at 4 h. It is concluded that, in patients who have incompletely reversible defects on early redistribution imaging at 4 h, late redistribution imaging after 24 h will demonstrate additional redistribution in 30% of the patients.     

歼击机飞行员神经精神类疾病谱分析

目的 探讨歼击机飞行员神经精神类疾病的分布规律. 方法 回顾性分析1965～2006年在我院住院诊治的436例歼击机飞行员的临床资料,统计不同疾病类型,不同年龄段的飞行结论 ,并进行比较. 结果 常见的神经精神类疾病分别为空中晕厥/加速度耐力不良、地面晕厥、血管性头痛、神经症等,发病年龄相对集中在30～35岁.癫痫、空中晕厥/加速度耐力不良和其他神经精神类疾病(主要是抑郁症、恶劣心境等)是停飞的重要原因. 结论 歼击机飞行员的神经精神类疾病大多数无器质性病变,但治愈合格率低,停飞率高,且心理和精神类疾病有上升趋势,对其原因进行分析有助于提高航卫保障质量.     

The value of delayed (24-hour) bone scintigraphy

Delayed 24-hour scintigraphy was performed in 23 patients. It was found to be useful in enhancing abnormal uptake, enabling better anatomic localization and verifying doubtful uptakes in the 4-hour study. The underlying causes of these observations are probably a better lesion-to-blood ratio and a slow uptake in certain lesions.