摘要
目的观察中等强度反复正加速度(+Gz)暴露是否会对飞行员心脏功能产生不利影响。方法38名歼击机飞行员接受离心机检查,+Gz暴露峰值从+2.5Gz/10s开始。通过后,每次再递增+0.5Gz^+1.0Gz,达到最高加速度暴露强度+4.5Gz/10s后结束检查。观察飞行员+Gz暴露前后心脏超声多项心功能指标的变化。结果飞行员+Gz暴露后2~4h,左室射血分数(EF)、短轴缩短率(ΔD)、主动脉血流速度、肺动脉血流速度和二尖瓣E峰速度,以及左心房收缩末前后径、左心室收缩末前后径、左右径和左心室舒张末左右径与暴露前比较变化不明显(P>0.05)。二尖瓣A峰速度轻度增加(P<0.01),左心室舒张末前后径和E/A峰速比值有所减小(P<0.05)。其中12名飞行员+Gz暴露后24h,EF、ΔD和二尖瓣A峰速度较暴露前轻度增加(P<0.05),E/A峰速比值仍有所减小(P<0.05)。结论中等强度反复+Gz暴露对飞行员心脏收缩功能无明显影响,但对心脏舒张晚期功能可造成暂时轻度不利影响,24h后趋向恢复,提示应重视+Gz暴露后飞行员心脏功能的保护。
Objective To investigate the harmful effects of repeated positive acceleration （Jr-Gz） in medium intensity on cardiac function of pilots. Methods The centrifuge test of ＋Gz tolerance was performed in 38 fighter pilots. The q-Gz exposure began from ＋ 2.5Gz/10s, when passed, then 0. 5～1.0Gz was added each time, and the maximum ＋Gz exposure was ＋4. 25～4. 5Gz/10s. Several indices of cardiac systolic and diastolic functions were measured by echoeardiography before and after ＋Gz exposure. Results As compared with the control values before ＋Gz exposure, no significant changes （P〉0. 05） were found in ejection fraction （EF）, fractional shortening of left ventricle （DD）, blood flow velocity through aortic valve, blood flow velocity through pulmonary valve, E peak velocity of mitral valve, left atrial end-systolic anterior-posterior diameter, left ventricular end systolic anteriorposterior diameter, left ventricular end-systolic left-right diameter and left ventricular end diastolic left right diameter after 2-4 hours of ＋Gz exposure. A peak velocity in mitral valve slightly increased （P〈0.01）, left ventricular end-diastolic anterior-posterior diameter and E/A peak velocity ratio decreased （P〈 0.05）. After 24 h of ＋Gz exposure, EF, DD and A peak velocity in mitral valve slightly increased （P〈0. 05）, E/A peak velocity ratio was also slightly decreased （P〈0. 05）. Conclusion Repeated ＋Gz exposure in medium intensity seems not to influence the cardiac systolic function of pilots, but may have a slight and temporary harmful effect on cardiac diastolic function, implying that attention should be paid to protect the cardiac function of pilots after a repeated ＋Gz exposure.
出处
《解放军医学杂志》
CAS
CSCD
北大核心
2008年第6期773-775,共3页
Medical Journal of Chinese People's Liberation Army
关键词
正加速度
心脏功能试验
超声心动图
positive acceleration
heart function tests
echocardiography
