CDFI评价M-3动作对颈动脉血流影响的价值

目的：探讨飞行中实施Ｍ－３动作时颈总动脉（ＣＣＡ）血流动力学变化及意义。方法：应用彩色多普勒血流显像（ＣＤＦＩ）测量３２名战斗机飞行员在地面＋１Ｇｚ条件下实施Ｍ－３动作时ＣＣＡ收缩期峰１速度（Ｖｓ１）、收缩峰２速度（Ｖｓ２）、舒张峰速度（ＶＤ）、舒张末速度（Ｖｄ）、平均血流速度（Ｖｍ）、血流量（Ｖ）、心率（ＨＲ）、心水平收缩压（ＨＳＰ）、血管阻力指数（ＲＩ）、搏动指数（ＰＩ）等参数。结果：与动作前平静状态参数比较，Ｖｓ２、ＶＤ、Ｖｍ、Ｖ和ＨＳＰ分别提高４１％、３１％、２３％、２６％和５６％（Ｐ＜０．０１），ＲＩ和ＰＩ分别降低７％和２６％（Ｐ＜０．０１），Ｖｍ与Ｖ间呈正相关（ｒ＝０．６９，Ｐ＜０．０５），Ｖｓ１、Ｖｄ和ＨＲ与平静时比较无显著性差异（Ｐ＞０．０５）。结论：Ｍ－３动作能增加静脉回心血量，提高大动脉血压，加快ＣＣＡ的Ｖｓ２、ＶＤ和Ｖｍ值，降低脑血管阻力，有利于维持脑部供血

CDFI Evaluation of M-3 Maneuver Effect on Common Carotid Hemody namics

Objective: To study the M3 maneuver effect on common carotid hemodynamics and its significance. Methods: CDFI was used to measure systolic peak1 flow velocity(Vs1),systolic peak 2 flow velocity (Vs2),diastolic peak flow velocity(VD),end diastolic flow velocity(Vd),mean flow velocity(Vm),blood flow volume(V),heart systolic pressure(HSP),heart rate(HR),resistance index(RI)and pulsatility index(PI)of 32 pilots during M3 maneuver in 1G condition. Results: The values of Vs2,VD,Vm,V and HSP in M3 maneuver raised 41%,31%,23%,26% and 56% respectively as compared with that in rest condition.RI and PI droped 7% and 26%,respectively.Positive correlation in Vm and V(r=069,P<005),no significant difference in Vs1,Vd and HR as compared with that in rest condition(P>005)were found. Conclusion: The major effect of M3 maneuver was to raise Vs2,VD,Vm and HSP,drop cerebral vascular resistance,maintain cerebral blood supply.